Attachment style and parental bonding: Relationships with fibromyalgia and alexithymia.

OBJECTIVES: Fibromyalgia (FM) is a chronic pain syndrome, and alexithymia, which is a condition that is characterised by deficits in emotional self-awareness, is highly prevalent among individuals with FM. Insecure attachment styles and inadequate parental care appear to play an important role in the onset and maintenance of both alexithymia and chronic pain. Therefore, the present study aimed to examine the associations between attachment styles, parental bonding, and alexithymia among patients with FM and healthy controls (HC).
METHODS: All participants completed a battery of tests that assessed alexithymia, attachment styles, and parental bonding. Two logistic regression models were tested to examine whether these variables predict (a) group membership (i.e. patients with FM vs. HC) and (b) the likelihood of having alexithymia (i.e. among patients with FM and HC).
RESULTS: Alexithymia (i.e. difficulty identifying and describing feelings subscales of the 20-item Toronto Alexithymia Scale) significantly predicted group membership (i.e. the likelihood of having FM). On the other hand, educational level and dismissive attachment (i.e. the discomfort with closeness and relationships as secondary subscales of the Attachment Style Questionnaire) were the only significant predictors of the likelihood of having alexithymia.
CONCLUSIONS: These findings highlight both the relevance of alexithymic traits to the definition of FM and centrality of an insecure attachment style to the manifestation of alexithymia.

Introduction

Fibromyalgia (FM) is a syndrome that is primarily characterised by chronic and widespread musculoskeletal pain [1, 2], with high incidence among women [3]. The etiopathogenesis of this syndrome is complex and multifactorial, and a series of other conditions such as physical and mental fatigue, disrupted sleep, headaches, irritable bowel syndrome, psychiatric disorders, and cognitive impairments are often associated with chronic pain [4-8].

In recent years, researchers have begun to redirect their attention towards alexithymia, which is a personality trait that is characterised by difficulties in identifying and describing subjective feelings, restricted imaginative processes, and an externally oriented cognitive style [9-11]. Most studies have reported that there is a high prevalence of alexithymia among patients with FM, and the figures range from 48% to 64% [12-14]. With regard to the aetiology of alexithymia, several theoretical models suggest that negative childhood experiences such as traumatic events and inadequate parental bonding may play an important role in the onset of alexithymia [10, 15–17].

Since the ‘80s, different authors have proposed developmental frameworks of affect regulation that underscore the important regulatory function of caregivers in modulating an infant’s emotional states [18-20]. Accordingly, research has also shown that children with insecure attachments, specifically those with an avoidant attachment style, tend to be unable to express negative emotions, especially in highly stressful situations [21, 22].

In more recent years, Fonagy et al. [23] have expanded pre-existing models by delineating the important correlation that exists between the ability of the caregiver to adequately mirror the child’s affective states and the child’s capacity to effectively represent, tolerate, and regulate affective states.

Several studies have examined the relationship between parental bonding and alexithymia, using both clinical and healthy populations. For instance, a recent meta-analysis [24] showed that there is a negative association between maternal care and alexithymia and a positive association between maternal overprotection and alexithymia among student samples. Relationships between attachment styles and the capacity to represent affective states have also been observed among other non-clinical adult samples. Indeed, several studies have shown that insecure attachment is related to alexithymia [25-28] and that dismissive attachment, in particular, is linked to dysfunctional emotion regulation processing [29, 30].

With regard to clinical populations, the findings of a meta-analysis that was undertaken by Thorbeg et al. [24] highlighted the significant negative association that exists between parental care and alexithymia; however, a significant positive association was found between parental overprotection and alexithymia. Similarly, Gil et al. [31] reported positive associations between ambivalent attachment styles, parental bonding, and alexithymia among patients with somatoform disorders. Particularly, with regard to chronic pain patients, many studies have investigated the relationship between attachment style and chronic pain [32-34] as well as parental bonding and chronic pain [35]. The findings suggest that insecure attachment and inadequate parental care are significantly associated with chronic pain. However, little attention has been paid to the associations between parental bonding, attachment styles, and alexithymia specifically in patients with FM. Among the few studies available that have examined these variables in patients with FM, Gil et al. [36] showed positive associations between alexithymia scores and those that are yielded by both the ‘Maternal Abuse’ and ‘Paternal Indifference’ subscales of the Measure of Parental Style (MOPS). Moreover, Peñacoba et al. [37] found positive associations between alexithymia and insecure attachment (both anxious-ambivalent and avoidant attachment styles) in their sample of patients with FM.

The present study aimed to examine deeply the associations between attachment styles, parental bonding, and alexithymia among patients with FM and healthy controls (HC). Particularly, we aimed to discern if parental bonding and adult attachment styles might play a key role in predicting group membership (i.e. patients with FM vs. HC) or otherwise if these variables could only predict the likelihood of having alexithymia.

Materials and methods

Participants and procedure

One hundred female participants with FM were consecutively recruited from the Fibromyalgia Integrated Outpatient Unit (FIOU), which is a multidisciplinary unit that functions based on collaborations between rheumatologists, psychologists, and psychiatrists at the ‘Città della Salute e della Scienza’, Turin, Italy. All patients had a primary diagnosis of FM, which had been made by an expert rheumatologist in the field, using ACR criteria of 2010 [2]. The usual clinical practice for patients with FM presenting themselves at our unit includes a first visit with the rheumatologist that made/confirm the diagnosis of FM and a second visit with a psychologist and a psychiatrist together with the rheumatologist in order to formalise the patient care by the FIOU. During a separate session, participants filled out psychological scales after a clinical and psychological interview that assessed sociodemographic and clinical characteristics.

The recruitment took place in the period from September 2016 to January 2018. Patients were recruited consecutively; therefore, the resulting sample is more likely to represent the target population than one resulting from simple convenience sampling.

One hundred and seven healthy women were recruited in order to match the demographic characteristics (i.e. age, gender and educational level) of the FM patients and assigned to the HC group. Healthy women were enrolled from different social and cultural backgrounds in a community sample in Turin. Participants filled in paper-and-pencil versions of the questionnaires, during a face-to-face meeting. The criteria for exclusion from both the FM and HC groups were as follows: being younger than 18 years of age, having a low educational level (< 5 years), lacking fluency in the Italian language, and the presence or a history of a neurological or psychiatric disorder. Furthermore, the presence of rheumatic diseases or chronic pain was included as an additional exclusion criterion for the HC sample only.

This study was approved by the ethics committee of the ‘Città della Salute e della Scienza’, Turin, Italy (N. CS/506), and was conducted in accordance with the Declaration of Helsinki. All participants provided written informed consent to participate in the study.

Measures

No previous study has been published yet, using the present dataset.

Sociodemographic and clinical information

Participants were asked to provide sociodemographic (i.e. age, educational level, marital status, and occupation) and clinical information (i.e. duration and severity of illness). Particularly regarding the educational level, we asked both patients with FM and HC to indicate the total of how many years of education they achieved.

In addition, as an index of pain intensity for the patients with FM, the item “Pain” of the Italian version of the Revised Fibromyalgia Impact Questionnaire (FIQ-R) [38, 39] was used to assess the average intensity of pain in the previous week on a scale ranging between 0 and 10.

Alexithymia

The Toronto Alexithymia Scale (TAS-20) [40, 41] is a self-report instrument. It comprises 20 items, each of which requires responses to be recorded on a 5-point Likert-type scale. Item scores yield a total score and three subscale scores. The three subscales assess the different features of alexithymia as follows: (a) difficulty identifying feelings (DIF), which refers to the inability to distinguish between specific emotions or emotions and the bodily sensations of emotional arousal; (b) difficulty describing feelings (DDF), which refers to the inability to verbalise one’s emotions to other people; and (c) externally oriented thinking (EOT), which refers to the tendency to direct attention externally rather than towards inner emotional experiences [41, 42]. The cut-off values and interpretations for the total scores are as follows: ≤ 51 = no alexithymia, 52–60 = borderline alexithymia, ≥ 61 = alexithymia. This scale has demonstrated good internal consistency (Cronbach’s α ≥ 0.70) and test-retest reliability [41].

Parental bonding and attachment style

The Parental Bonding Instrument (PBI) is a self-report questionnaire that assesses retrospective accounts of parenting styles that an individual had experienced during the first 16 years of life [43, 44]. It consists of 25 items, each of which requires responses to be recorded on 4-point Likert scale. The PBI assesses maternal and paternal parenting styles independently. Consequently, the PBI assesses respondents’ perceptions of the relationships that they share with each parent. Two dimensions of parenting styles are measured by the PBI: care and overprotection. A low score on the care subscale is indicative of perceived parental neglect and rejection, whereas a high score is indicative of perceived parental warmth and affection. A high score on the overprotection subscale is indicative of perceived excessive control and intrusive parenting, whereas a low score is indicative of perceived parental acceptance of a child’s independence and autonomy. The instrument has demonstrated strong psychometric properties, including long-term temporal stability [45] and high internal consistency (Cronbach’s α = 0.74–0.95) [43].

The Attachment Style Questionnaire (ASQ) is a 40-item self-report questionnaire that assesses attachment styles among adults [46, 47]. The respondent is required to rate each item on a 6-point Likert scale, which ranges from ‘Totally Disagree’ to ‘Totally Agree’.

The ASQ consists of five subscales: confidence, preoccupation with relationships, relationships as secondary, discomfort with closeness, and need for approval. Particularly, discomfort with closeness is a theme that is central to Hazan & Shaver’s conceptualisation of avoidant attachment [48]. Need for approval refers to the need for acceptance and approval from others and is characteristic of fearful and preoccupied attachment [49]. Preoccupation with relationships entails an anxious and dependent approach to relationships, and it is a core feature of Hazan & Shaver’s original conceptualisation of anxious/ambivalent attachment [48]. The dimension, relationships as secondary, is consistent with Bartholomew’s concept of dismissive attachment [50]. Finally, confidence (in self and others) is indicative of a secure attachment style. In the present study, a dimensional approach was adopted.

All subscales of the ASQ have demonstrated high internal consistency (Cronbach’s α = 0.80) and test-retest reliability over a 10-week period (r = 0.76) [46].

Statistical analyses

Statistical analyses were conducted using the Statistical Package for Social Sciences (SPSS) version 25.0 (IBM SPSS Statistics for Macintosh, Armonk, NY, USA: IBM Corp.).

Indices of asymmetry and kurtosis were used to test the normality of the data. Values for asymmetry and kurtosis that were between -1 and +1 were considered to be acceptable and indicative of a normal univariate distribution. As per these specifications, all of the variables were found to be normally distributed.

Independent samples t-test and Pearson’s chi-square test (χ2) were used to examine group differences in continuous and categorical variables, respectively. Effect size was determined by calculating Cohen’s d values.

Finally, two binary logistic regression analyses were conducted. The first logistic regression analysis was conducted to examine if the scores that are yielded by the measures of parental bonding (i.e. PBI–first predictor group entered into the regression model), attachment styles (i.e. ASQ–second predictor group), and alexithymia (i.e. TAS-20 –third predictor group), predict group membership (i.e. participants with FM vs. HC). The second logistic regression analysis was conducted to examine the effects of demographic variables (first predictor group entered into the regression model), parental bonding (second predictor group), and attachment styles (third predictor group) on the likelihood of having alexithymia. For this analysis, all participants (i.e. both patients with FM and HC) were divided in two groups based on their total scores on the TAS-20 (alexithymic group: total score ≥ 61 vs. non-alexithymic group: total score < 61).

To avoid unnecessary reductions in statistical power, only those variables that were significantly different between the two groups (i.e. participants with FM vs. HC or alexithymic vs. non-alexithymic participants), as per the results of preliminary t-tests, were included in the logistic regression models. The enter method was used to include the variables of the predictor groups. A p < .01 significance level was used to further reduce the likelihood of Type I errors that may result from the conventionally used significance level of p < .05. Adjusted odds ratios and 95% confidence intervals were calculated for the predictors of both logistic regression models.

Results

Patients with FM versus HC

Sociodemographic and clinical data

The sociodemographic and clinical characteristics of patients with FM and HC are presented in Table 1.

Table 1

Sociodemographic and clinical characteristics of the fibromyalgic patients and healthy controls.

Mean (SD), percentage, and t-test are listed.

	FM (N = 100)	HC (N = 107)	Test (df)	p
Age (years)	50.15 (10.51)	47.37 (10.39)	t(205) = 1.910	.058
Educational level (years)	11.78 (3.42)	12.58 (3.01)	t(197.62) = -1.780	.077
Duration of illness (months)	97.35 (95.10)	–
Marital status			χ2(4) = 9.814	.044
Never-married	12 (12.1%)	14 (13.1%)
Cohabitant	11 (11.1%)	11 (10.3%)
Married	54 (54.4%)	72 (67.3%)
Separated/divorced	16 (16.2%)	10 (9.3%)
Widowed	6 (6.1%)	0 (0.0%)
Occupation			χ2(4) = 13.470	.009
Student	3 (3.0%)	6 (5.6%)
Employed	63 (63.0%)	86 (80.4%)
Unemployed	10 (10.0%)	2 (1.9%)
Retired	8 (8.0%)	6 (5.6%)
Housewife	16 (16.0%)	7 (6.5%)
FIQ-R Pain	7.56 (1.85)	–

FM = Fibromyalgia; HC = Healthy Controls; df = Degrees of freedom; FIQ-R = Fibromyalgia Impact Questionnaire Revised version.

Results of the t-tests revealed that patients with FM and HC were matched for age and educational level. With regard to the clinical characteristics of the FM group, patients had had their illness for an average of 8 years and reported a high rate of pain intensity (FIQ-R Pain: 7.56 ± 1.85).

Alexithymia, parental bonding, and attachment styles

Statistics for alexithymia, parental bonding, and attachment styles are presented in Table 2.

Table 2

Alexithymia, parental bonding, and attachment styles in fibromyalgic patients vs. healthy controls.

Mean (SD), t-test, and Cohen’s d are listed.

	FM (N = 100)	HC (N = 107)	Test (df)	p	Effect size
Alexithymia
TAS-20 DIF	22.41 (7.27)	13.56 (5.85)	t(190.045) = 9.611	<.001	d = 1.34
TAS-20 DDF	14.10 (5.22)	11.91 (4.09)	t(187.432) = 3.351	.001	d = 0.47
TAS-20 EOT	17.29 (5.02)	18.27 (4.48)	t(205) = -1.485	.139	d = 0.21
TAS-20 Total	53.80 (13.72)	43.74 (11.42)	t(193.080) = 5.713	<.001	d = 0.80
Attachment variables
PBI Maternal Care	18.40 (9.06)	24.19 (7.32)	t(190.416) = -5.057	<.001	d = 0.70
PBI Maternal Overprotection	18.46 (8.89)	13.62 (7.25)	t(191.183) = 4.265	<.001	d = 0.60
PBI Paternal Care	17.58 (10.17)	23.78 (8.15)	t(179.959) = -4.736	<.001	d = 0.67
PBI Paternal Overprotection	18.11 (9.54)	12.90 (8.00)	t(186.244) = 4.168	<.001	d = 0.59
ASQ Confidence	29.92 (6.12)	32.91 (4.67)	t(205) = -3.962	<.001	d = 0.55
ASQ Discomfort with Closeness	38.95 (9.01)	35.06 (7.34)	t(205) = 3.417	.001	d = 0.47
ASQ Relationships as Secondary	16.43 (5.87)	14.86 (5.23)	t(205) = 2.034	.043	d = 0.28
ASQ Need for Approval	21.95 (5.79)	18.62 (5.95)	t(205) = 4.078	<.001	d = 0.57
ASQ Preoccupation with Relationships	28.91 (7.83)	24.79 (6.08)	t(205) = 4.251	<.001	d = 0.59

FM = Fibromyalgia; HC = Healthy Controls; df = Degrees of freedom; TAS-20 = Twenty-item Toronto Alexithymia Scale; TAS-20 DIF = Difficulty Identifying Feelings factor of Toronto Alexithymia Scale; TAS-20 DDF = Difficulty Describing Feelings factor of Toronto Alexithymia Scale; TAS-20 EOT = Externally-Oriented Thinking factor of Toronto Alexithymia Scale; PBI = Parental Bonding Instrument; ASQ = Attachment Style Questionnaire.

With regard to alexithymia, statistical analyses revealed that the FM group obtained significantly higher DIF (p < .001, d = 1.34) and DDF subscale (p = .001, d = 0.47) and total (p < .001, d = 0.80) scores than HC. Participants were classified into categories based on the cut-off values for the TAS-20 scores. Whereas 35.0% (35/100) of patients with FM were alexithymic and 21.0% (21/100) of them were borderline, 8.4% (9/107) and 15.9% (17/107) of HC were alexithymic and borderline, respectively (χ2(2) = 26.530, p < .001).

With regard to attachment styles, patients with FM obtained lower scores on the confidence subscale of the ASQ, when compared to HC (p < .001, d = 0.55). However, patients with FM obtained higher scores on the discomfort with closeness (p = .001, d = 0.47), relationships as secondary (p = .043, d = 0.28), need for approval (p < .001, d = 0.57), and preoccupation with relationships (p < .001, d = 0.59) subscales of the ASQ. Further, with regard to parental bonding, patients with FM obtained higher scores on the maternal (p < .001, d = 0.60) and paternal (p < .001, d = 0.59) overprotection subscales of the PBI, when compared to HC. On the contrary, patients with FM obtained lower scores on the maternal (p < .001, d = 0.70) and paternal (p < .001, d = 0.67) care subscales of the PBI, when compared to HC.

Logistic regression

Hierarchical binomial logistic regression analysis was conducted to examine if alexithymia, parental bonding, and attachment styles predict group membership (i.e. patients with FM vs. HC). Only those variables that were significantly different between the two groups, as per the results of preliminary t-tests, were included in the logistic regression models.

In Model 1, the PBI subscale scores were entered as predictors. The model was statistically significant, χ2 (4) = 39.848, p < .001, and the Hosmer-Lemeshow test results were as follows: χ2 (8) = 3.674, p = .885. The model explained 24% (Nagelkerke R) of the variance and correctly classified 69% of the cases. Among the predictors, both maternal (p = .009) and paternal (p = .035) care factors were statistically significant (Table 3).

Table 3

Logistic regression predicting likelihood of Fibromyalgia vs. healthy controls based on parental bonding, attachment styles, and alexithymia.

	Model 1a			Model 2b			Model 3c
Predictor variables	OR	95% CI	Wald	OR	95% CI	Wald	OR	95% CI	Wald
PBI Maternal Care	1.061	1.015–1.109	6.746**	1.062	1.012–1.114	5.934*	1.054	0.996–1.116	3.373
PBI Maternal Overprotection	0.983	0.938–1.029	0.552	0.989	0.940–1.040	0.186	0.992	0.932–1.055	0.068
PBI Paternal Care	1.041	1.003–1.081	4.449*	1.028	0.987–1.070	1.712	1.033	0.985–1.083	1.780
PBI Paternal Overprotection	0.961	0.923–1.002	3.483	0.961	0.918–1.005	3.045	0.959	0.912–1.009	2.648
ASQ Confidence				1.050	0.986–1.120	2.296	1.061	0.984–1.144	2.344
ASQ Discomfort with Closeness				0.979	0.938–1.022	0.957	1.005	0.956–1.057	0.038
ASQ Need for Approval				0.960	0.899–1.024	1.534	1.038	0.958–1.125	0.843
ASQ Preoccupation with Relationships				0.951	0.897–1.009	2.791	0.964	0.905–1.027	1.279
TAS-20 DIF							0.772	0.706–0.845	31.447**
TAS-20 DDF							1.168	1.041–1.331	6.972**

χ2 (4) = 38.848, p < .001. Nagelkerke R2 = .24.

χ2 (8) = 58.304, p < .001. Nagelkerke R2 = .34.

χ2 (10) = 107.980, p < .001. Nagelkerke R2 = .56.

OR = Odds Ratio; CI = Confidence Interval; PBI = Parental Bonding Instrument; ASQ = Attachment Style Questionnaire; TAS-20 DIF = Difficulty Identifying Feelings factor of Toronto Alexithymia Scale; TAS-20 DDF = Difficulty Describing Feelings factor of Toronto Alexithymia Scale.

* p < .05;

** p < .01

In Model 2, ASQ subscale scores were entered as predictors. The likelihood-ratio test statistic revealed that Model 2 was superior to Model 1 in terms of overall model fit. The block was statistically significant, χ2 (4) = 18.456, p ≤ .001, and the Hosmer-Lemeshow test yielded the following results: χ2 (8) = 6.142, p = .631. The model explained 34% (Nagelkerke R) of the variance and correctly classified 72.5% of the cases. Among the predictors, only maternal care (p = .015) was statistically significant (Table 3).

In Model 3, the TAS-20 subscale scores were entered as predictors. The likelihood-ratio test statistic revealed that Model 3 was superior to Model 2 in terms of overall model fit. The block was statistically significant, χ2 (2) = 49.676, p < .001, and the Hosmer-Lemeshow test yielded the following results: χ2 (8) = 3.234, p = .919. The model explained 56% (Nagelkerke R) of the variance and correctly classified 80% of the cases. Maternal care ceased to be statistically significant, and the TAS-20 DIF (p < .001) and DDF (p = .008) subscales scores emerged as the only two statistically significant predictors (Table 3).

Alexithymic versus non-alexithymic participants

Demographic data, parental bonding, and attachment styles

Statistics for demographic variables, parental bonding, and attachment styles are presented in Table 4.

Table 4

Demographic characteristics, parental bonding, and attachment styles in alexithymic vs. non-alexithymic groups.

Mean (SD), t-test, and Cohen’s d are listed.

	Alexithymic Group (N = 44)	Non-alexithymic Group (N = 163)	Test (df)	p	Effect size
Age (years)	51.41 (8.85)	47.99 (10.83)	t(205) = -1.928	.055	d = 0.35
Educational level (years)	10.59 (2.84)	12.63 (3.20)	t(205) = 3.826	<.001	d = 0.67
Attachment variables
PBI Maternal Care	18.39 (9.72)	22.19 (8.23)	t(204) = 2.612	.010	d = 0.42
PBI Maternal Overprotection	16.48 (9.31)	15.83 (8.19)	t(204) = -0.449	.654	d = 0.07
PBI Paternal Care	17.71 (10.92)	21.68 (9.15)	t(57.100) = 2.161	.035	d = 0.39
PBI Paternal Overprotection	16.45 (9.45)	15.07 (9.04)	t(199) = -0.874	.383	d = 0.15
ASQ Confidence	29.89 (6.29)	31.89 (5.35)	t(205) = 2.120	.035	d = 0.34
ASQ Discomfort with Closeness	40.93 (8.34)	35.86 (8.11)	t(205) = -3.659	<.001	d = 0.62
ASQ Relationships as Secondary	18.91 (6.64)	14.73 (4.93)	t(54.436) = -3.895	<.001	d = 0.71
ASQ Need for Approval	23.34 (6.49)	19.39 (5.72)	t(205) = -3.952	<.001	d = 0.65
ASQ Preoccupation with Relationships	29.27 (7.00)	26.10 (7.20)	t(205) = -2.605	<.001	d = 0.45

df = Degrees of freedom; PBI = Parental Bonding Instrument; ASQ = Attachment Style Questionnaire.

With regard to attachment styles, alexithymic individuals reported lower scores on the confidence subscale of the ASQ, when compared to non-alexithymic individuals (p < .035, d = 0.34). Further, the alexithymic group obtained higher scores on the discomfort with closeness (p < .001, d = 0.62), relationships as secondary (p < .001, d = 0.71), need for approval (p < .001, d = 0.65), and preoccupation with relationships (p < .001, d = 0.45) subscales of the ASQ. With regard to parental bonding, alexithymic individuals obtained lower scores on the maternal (p = .010, d = 0.42) and paternal (p < .035, d = 0.39) care subscales of the PBI, when compared to non-alexithymic individuals. There was no significant group difference in maternal and paternal overprotection (p = NS).

Hierarchical binomial logistic regression analysis was conducted to examine the effects of demographic variables, parental bonding, and attachment styles on the likelihood of having alexithymia. Only those variables that were significantly different between the two groups, as per the results of preliminary t-tests, were included in the logistic regression models.

In Model 1, educational level was entered as a predictor. The model was statistically significant, χ2 (1) = 14.886, p < .001, and the Hosmer-Lemeshow test results were as follows: χ2 (3) = 4.937, p = .176. The model explained 11% (Nagelkerke R) of the variance and correctly classified 78.2% of the cases. Educational level was found to be a statistically significant predictor (p < .001) (Table 5).

Table 5

Logistic regression predicting likelihood of alexithymia vs. non-alexithymia based on demographic characteristics, parental bonding, and attachment styles.

	Model 1a			Model 2b			Model 3c
Predictor variables	OR	95% CI	Wald	OR	95% CI	Wald	OR	95% CI	Wald
Educational level	0.805	0.716–0.904	13.328**	0.812	0.721–0.914	11.801**	0.813	0.714–0.927	9.636**
PBI Maternal Care				0.957	0.920–0.996	4.597*	0.963	0.922–1.006	2.839
ASQ Discomfort with Closeness							1.064	1.010–1.121	5.509*
ASQ Relationships as Secondary							1.094	1.018–1.176	5.509*
ASQ Need for Approval							1.051	0.973–1.135	1.611
ASQ Preoccupation with Relationships							1.011	0.951–1.074	0.113

χ2 (1) = 14.886, p <.001. Nagelkerke R2 = .11.

χ2 (6) = 19.532, p <.001. Nagelkerke R2 = .14.

χ2 (8) = 44.153, p <.001. Nagelkerke R2 = .30.

OR = Odds Ratio; CI = Confidence Interval; PBI = Parental Bonding Instrument; ASQ = Attachment Style Questionnaire.

* p <.05;

** p <.01

In Model 2, maternal care was entered as a predictor. The likelihood-ratio test statistic revealed that Model 2 was superior to Model 1 in terms of overall model fit. The block was statistically significant, χ2 (1) = 4.645, p = .031, and the Hosmer-Lemeshow test results were as follows: χ2 (7) = 13.407, p = .063. The model explained 14% (Nagelkerke R) of the variance and correctly classified 79.1% of the cases. Both educational level (p ≤ .001) and maternal care (p = .032) emerged as statistically significant predictors (Table 5). Finally, in Model 3, variables pertaining to attachment styles were included. The likelihood-ratio test statistic revealed that Model 3 was superior to Model 2 in terms of overall model fit. The block was statistically significant, χ2 (4) = 24.621, p = < .001, and the Hosmer-Lemeshow test results were as follows: χ2 (8) = 9.333, p = .315. This final model explained 30% (Nagelkerke R) of the variance and correctly classified 81.1% of the cases. Educational level (p = .002) and scores on the relationships as secondary (p = .015) and discomfort with closeness (p = .019) subscales of the ASQ emerged as statistically significant predictors (Table 5).

Discussion

The present study aimed to investigate the associations between parental bonding, adult attachment styles, and alexithymia among patients with FM and HC. Previous studies have already been carried out by our research group (e.g., [8; 14; 51–53]), in order to investigate the association between alexithymia and other FM-related variables in this clinical population. However, the present report represents a unique and different contribution, as we have never evaluated before attachment styles and the association with alexithymia among patients with FM and HC. In that way, we contributed to increasing both the body of literature on this topic, which has been sparsely investigated to date, and the knowledge on the psychological aspects, with particular regard to the relationship between alexithymia and attachment in patients with FM compared to HC.

As a first goal of the study, we examined whether parental bonding, adult attachment styles, and alexithymia predict group membership (i.e. patients with FM vs. HC).

The present results, consistently with previous findings [36, 54,55], revealed that levels of alexithymia were higher among patients with FM than HC. On the other hand, with regard to parental bonding, patients with FM obtained lower scores on the maternal and paternal care subscales and higher scores on the maternal and paternal overprotection subscales of the PBI. These findings suggest that, when compared to HC, our sample of patients with FM may have experienced low levels of parental warmth and excessive control during their childhood as a result of the negligent, cold, dismissive, and intrusive parenting styles of both their parents. These findings are consistent with the results of one other study, which investigated the role of parenting styles among patients with FM and found that a high prevalence of maternal abuse and paternal indifference was reported by patients with FM [36].

Further support for the association between adverse parenting styles and chronic illness stems from past findings, which showed significant differences between patients with different chronic medical conditions and HC [35, 56, 57]. For instance, Agostini et al. [56] found that patients with irritable bowel syndrome had reported inadequacies in the parenting styles of their parents as well as personal difficulties in demonstrating warmth, understanding, independence, and individuation from the parental bond. In another study, Agostini et al. [57] found that patients with Crohn’s disease perceived their parents’ behaviours to be characterised by lower levels of maternal care and higher levels of paternal overprotection, when compared to HC.

With regard to the dimensions of adult attachment, patients with FM obtained higher scores on the discomfort with closeness (corresponds to Hazan & Shaver’s conceptualisation of avoidant attachment) and relationships as secondary (corresponds to Bartholomew & Horowitz’s conceptualisation of dismissive attachment) subscales of the ASQ, when compared to HC. Moreover, our findings suggest that patients with FM are more likely to seek approval and care from significant others (i.e. need for approval subscale of the ASQ) and be anxious about and dependent upon meaningful relationships (i.e. preoccupation with relationships subscale of the ASQ), when compared to HC. Finally, HC obtained significantly higher scores on the confidence subscale of the ASQ than patients with FM. This suggests that they have greater self-worth (lovability) and believe that other people are generally accepting and responsive. Our results are in line with a previous study of Peñacoba et al. [37], which found that patients with FM reported significantly higher scores compared to the HC group for both insecure attachment dimensions they evaluated (i.e. anxious-ambivalent attachment style–associated with low self-esteem, higher need of approval, and fear of rejection–and avoidant attachment style–characterised by greater emotional self-sufficiency and greater discomfort in intimacy).

To further examine the specific role that each of the examined factors (i.e. alexithymia, parental bonding, and attachment styles) plays in predicting group membership, hierarchical binomial logistic regression analysis was conducted. Contrary to our expectations, neither parental bonding nor attachment styles significantly predicted group membership (i.e. patients with FM vs. HC). In other words, although patients with FM reported higher levels of insecure attachment and greater difficulties in both maternal and paternal bonding than HC, these aspects do not appear to characterise this clinical population. Indeed, maternal care ceased to be a statistically significant predictor, when alexithymia was introduced into the model. In the final model, only alexithymia (both DIF and DDF factors) was a significant predictor of group membership. These results are attributable to the characteristic features of FM. Indeed, patients with FM typically represent a non-homogeneous clinical sample, and they also differ considerably in their personality traits and attachment styles. Furthermore, individuals with insecure attachment styles demonstrate different developmental trajectories and adopt defence mechanisms other than somatisation, which appears to primarily characterise patients with functional somatic syndromes such as FM.

Based on the above-described results, which show that parental bonding and adult attachment styles do not seem to significantly predict group membership (i.e. the likelihood of having FM), and on the available evidence, which highlights a strong association between alexithymia and insecure attachment, as a second aim of the present study we investigated whether alexithymia, rather than FM per se, could be significantly related with parental bonding and adult attachment styles. In order to test this second hypothesis, we first compared alexithymic and non-alexithymic individuals (considering the whole sample) on attachment variables.

The results showed that alexithymic individuals obtained significantly lower scores on the secure attachment dimension and higher scores on all insecure attachment dimensions, when compared to non-alexithymic individuals. These results concur with the findings of past studies that have highlighted the significant relationship that exists between insecure attachment and alexithymia [19, 26, 27, 58, 59]. For instance, Wearden et al. [59] conducted a study among students and found that the fearful aspect of avoidant attachment was associated with both higher levels of alexithymia and a greater tendency to report different medical symptoms.

With regard to parenting styles, alexithymic individuals obtained lower scores on both the maternal and paternal care subscales of the PBI, when compared to non-alexithymic individuals. This suggests that the former group of participants perceived their mothers and fathers to have not been warm and caring towards them during their childhood. Contrary to the meta-analytic findings of Thorbeg et al. [24], no statistically significant differences in scores on the overprotection subscales of the PBI emerged between alexithymic and non-alexithymic individuals.

In order to examine the associations between attachment and alexithymia more deeply, an additional hierarchical binomial logistic regression analysis was conducted. In the final model, educational level and the relationships as secondary and discomfort with closeness subscales of the ASQ emerged as significant predictors that explained the likelihood of having alexithymia. Contrary to our expectations, parenting styles did not emerge as a significant predictor of alexithymia. Indeed, the significant difference in maternal care, that emerged between the alexithymic and non-alexithymic individuals during the preliminary comparative analyses, ceased to be significant in the regression model.

With regard to adult attachment, both the relationships as secondary and discomfort with closeness dimensions of the ASQ were found to be significant predictors of alexithymia. These findings appear to be in line with those of Peñacoba et al. [37] who found no significant interactions between ‘group’ (FM vs HC) and ‘attachment style’ (secure, avoidant, and anxious-ambivalent) for either of the alexithymia factors. Intragroup comparisons revealed, instead, that both patients with FM and HC showed significant differences in the DDF factor of the TAS-20 between secure and avoidant styles, with higher scores reported for avoidant attachment.

A dismissive attachment style, which is resonant with the relationships as secondary and discomfort with closeness subscales of the ASQ, is considered to be related to experiencing consistently unresponsive caregiving practices during the early years. This can cause individuals to become compulsively self-reliant because they develop a negative view of others and a positive view of the self; consequently, they seek less intimacy from their attachment relationships and frequently suppress and deny their feelings [49] consistent with our results, several previous studies have found that dismissive attachment is linked to dysfunctional emotion regulation processes [29, 30, 60].

The present study also has some limitations. First, since we used self-report questionnaires, participants may have under-reported or exaggerated the severity of their symptoms. Performance-based measures or structured interviews should be employed in addition to traditional self-report measures to overcome this issue. Second, the PBI requires participants to retrospectively evaluate the relationships that they shared with their family members during the first 16 years of life. Thus, memory biases and defence mechanisms that such a measurement strategy may activate could have influenced participant responses. Moreover, the present study adopted a cross-sectional design, which does not permit us to draw concrete conclusions about the causality of the emergent relationships. Therefore, longitudinal studies are needed to investigate the association between parenting styles and alexithymia among patients with FM in greater depth.

Conclusions

The present study represents one of the few attempts to understand the complex relationships that exist between parental bonding, attachment styles, and alexithymia among patients with FM and HC.

In sum, the main results of our study suggest that alexithymic traits are the main characteristic feature of patients with FM. Indeed, although patients with FM primarily reported dysfunctional parental bonding and an insecure attachment style, these two factors do not seem to play a specific role in predicting the likelihood of having FM. Conversely, the two dimensions of insecure attachment (i.e. discomfort with closeness and relationships as secondary; ASQ) appear to play an important role in predicting the likelihood of having alexithymia.

The present findings have important implications for clinical practice. First, when working with patients with FM, clinical attention should be paid to not only the management of pain symptoms but also impairments in affect regulation and attachment dynamics. The use of group therapeutic interventions like the Attachment-Based Compassion Therapy that includes formal practices of mindfulness and visualizations based on self-compassion and the attachment style that was generated in childhood, could be an effective and also cheaper strategy for the treatment of patients with FM [61].

Second, among individuals with high levels of alexithymia, attention should be paid to the establishment of a secure therapeutic alliance because dismissive attachment patterns appear to play a role in the onset and maintenance of alexithymic traits.

Raw data used in the current study.

(XLSX)

Click here for additional data file.

31 Jan 2020

PONE-D-20-01350

Attachment style and parental bonding: relationships with fibromyalgia and alexithymia

PLOS ONE

Dear Dr Romeo,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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Plos One internal editors have carefully examined your manuscript. They recommend a Major Revision before sending the manuscript out for review. Please resubmit your manuscript addressing the following points:

1. Please provide additional information about the participant recruitment method and the demographic details of your participants. Please add in your methods section such details as a) the recruitment date range (month and year), b) a statement as to whether your sample can be considered representative of a larger population, c) a description of how participants were recruited, and d) descriptions of where participants were recruited and where the research took place.

2. Internal editors noticed that the present submission is closely related to previously published works, including:

- Tella MD, Enrici I, Castelli L, Colonna F, Fusaro E, Ghiggia A, Romeo A, Tesio V, Adenzato M. Alexithymia, not fibromyalgia, predicts the attribution of pain to anger-related facial expressions. J Affect Disord. 2018; 227: 272-279.

- Di Tella M, Tesio V, Ghiggia A, Romeo A, Colonna F, Fusaro E, Geminiani GC, Bruzzone M, Torta R, Castelli L. Coping strategies and perceived social support in fibromyalgia syndrome: Relationship with alexithymia. Scand J Psychol. 2018; 59(2): 167-176.

- Ghiggia A, Romeo A, Tesio V, Tella MD, Colonna F, Geminiani GC, Fusaro E, Castelli L. Alexithymia and depression in patients with fibromyalgia: When the whole is greater than the sum of its parts. Psychiatry Res. 2017 Sep;255:195-197.

- Di Tella M, Ghiggia A, Tesio V, Romeo A, Colonna F, Fusaro E, Torta R, Castelli L. Pain experience in Fibromyalgia Syndrome: The role of alexithymia and psychological distress. J Affect Disord. 2017 Jan 15;208:87-93.

- Tesio V, Di Tella M, Ghiggia A, Romeo A, Colonna F, Fusaro E, Geminiani GC, Castelli L. Alexithymia and Depression Affect Quality of Life in Patients With Chronic Pain: A Study on 205 Patients With Fibromyalgia. Front Psychol. 2018; 9: 442.

Please ensure that the related works have been adequately discussed, by commenting both in your cover letter and in the manuscript on how this work constitutes a distinct contribution. Please also ensure that any overlap in the dataset and analyses with previous works has not compromised the robustness of the statistical analysis (e.g., by removing required adjustments for multiple hypothesis testing). For further information on our submission guidelines on related manuscripts, please see " ext-link-type="uri" xlink:type="simple">http://journals.plos.org/plosone/s/submission-guidelines#loc-related-manuscripts.",

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24 Feb 2020

Dear Editor,

please find below a point by point response to all your comments. Thank you for the opportunity to clarify the issues that you raised.

1. Please provide additional information about the participant recruitment method and the demographic details of your participants. Please add in your methods section such details as a) the recruitment date range (month and year), b) a statement as to whether your sample can be considered representative of a larger population, c) a description of how participants were recruited, and d) descriptions of where participants were recruited and where the research took place.

Following your indications, we added the required information. Specifically, we added the recruitment date range, the recruitment details for both FM patients and HC. Our FM patients were recruited consecutively, so we added the following sentence in the text: “Patients were recruited consecutively; therefore, the resulting sample is more likely to represent the target population than one resulting from simple convenience sampling.”

2. Internal editors noticed that the present submission is closely related to previously published works, including:

- Di Tella MD, Enrici I, Castelli L, Colonna F, Fusaro E, Ghiggia A, Romeo A, Tesio V, Adenzato M. Alexithymia, not fibromyalgia, predicts the attribution of pain to anger-related facial expressions. J Affect Disord. 2018; 227: 272-279.

- Di Tella M, Tesio V, Ghiggia A, Romeo A, Colonna F, Fusaro E, Geminiani GC, Bruzzone M, Torta R, Castelli L. Coping strategies and perceived social support in fibromyalgia syndrome: Relationship with alexithymia. Scand J Psychol. 2018; 59(2): 167-176.

- Ghiggia A, Romeo A, Tesio V, Tella MD, Colonna F, Geminiani GC, Fusaro E, Castelli L. Alexithymia and depression in patients with fibromyalgia: When the whole is greater than the sum of its parts. Psychiatry Res. 2017 Sep;255:195-197.

- Di Tella M, Ghiggia A, Tesio V, Romeo A, Colonna F, Fusaro E, Torta R, Castelli L. Pain experience in Fibromyalgia Syndrome: The role of alexithymia and psychological distress. J Affect Disord. 2017 Jan 15;208:87-93.

- Tesio V, Di Tella M, Ghiggia A, Romeo A, Colonna F, Fusaro E, Geminiani GC, Castelli L. Alexithymia and Depression Affect Quality of Life in Patients With Chronic Pain: A Study on 205 Patients With Fibromyalgia. Front Psychol. 2018; 9: 442.

Please ensure that the related works have been adequately discussed, by commenting both in your cover letter and in the manuscript on how this work constitutes a distinct contribution.

Please also ensure that any overlap in the dataset and analyses with previous works has not compromised the robustness of the statistical analysis (e.g., by removing required adjustments for multiple hypothesis testing). For further information on our submission guidelines on related manuscripts, please see http://journals.plos.org/plosone/s/submission-guidelines#loc-related-manuscripts.

Following your remarks, we discussed the specificity of this paper with respect to our previous studies on FM patients both in the manuscript (discussion section) and in the opening lines of the cover letter.

Furthermore, we specified that the current dataset has not been used for other studies (we added the following sentence in the text: “No previous study has been published yet, using the present dataset”). We carried out different studies investigating the psychological components of FM patients, but for each study we enrolled different patients in different periods of time.

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

20 Mar 2020

PONE-D-20-01350R1

Attachment style and parental bonding: relationships with fibromyalgia and alexithymia

PLOS ONE

Dear Dr Romeo,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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To enhance the reproducibility of your results, we recommend that if applicable you deposit your laboratory protocols in protocols.io, where a protocol can be assigned its own identifier (DOI) such that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

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Kind regards,

Juan V. Luciano, Ph.D.

Academic Editor

PLOS ONE

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Reviewer #2: (No Response)

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Reviewer #2: Partly

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Reviewer #1: Yes

Reviewer #2: Yes

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Reviewer #1: Yes

Reviewer #2: Yes

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Reviewer #2: Yes

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Reviewer #1: Introduction.

Two recently published studies reported a higher prevalence of alexithymia in people with Fibromyalgia (48%-64%) than those reported in the introduction. It would be convenient to update this information.

References:

1. Front Psychol. 2019 Jul 31; 10: 1735. DOI: 10.3389/fpsyg.2019.01735.

2. Clin Exp Rheumatol 2019 Oct 9[Online ahead of print]

Methods.

A medical expert in the field made the diagnosis of Fibromyalgia. However, it is not clear if the doctor used any classification criteria (for example, ACR criteria 1990, 2010 or 2016) to unify the standards in the diagnosis in the sample. I consider it appropriate to clarify in the methods section.

Something to complement the description of the sample is if the center where the investigation was carried out, any patient with pain can go to the center (Primary Healthcare), or for their attention, the evaluation and referral of another doctor are necessary (Secondary / Tertiary Health Care).

There is duplicate information; for example, page 5, lines 106 and 112, repeat the time of inclusion of patients. The exclusion criteria are the same for both groups, with the exception that in the control group, patients with rheumatic diseases or chronic pain are excluded. I recommend presenting them in the same paragraph.

Results.

In the manuscript, there is any inconsistency between the number of people with fibromyalgia included. In the methods section, one hundred and seven patients report. In the headings of Table 1 and Table 2, 100 patients are reported. However, the sum of the variable's marital status and occupation includes only 99 patients. This information should be reviewed.

There is information that suggests gender differences in the prevalence of alexithymia. Because of the higher frequency of fibromyalgia in women, some studies only include women. The manuscript does not present the percentage of women involved in each of the groups. This information should be clarified.

Page 11, line 220. Consider changing the word "composite" to "total score" or "global score." Which better reflects the score of the 20 items on the TAS-20 scale.

Conclusions.

In the conclusions, I suggest removing "In spite of these limitations"

Reviewer #2: Attachment style and parental bonding: relationships with fibromyalgia and alexithymia

This article focuses on a particular area of interest, specifically “to examine the associations between attachment styles, parental bonding, and alexithymia among patients with fibromyalgia (FM) and healthy controls (HC)” (lines 22-24), nevertheless the method employed makes it look as if it were two independent studies with no apparent link, as if they weren’t connected enough to be part of the same manuscript: a) to analyze predictive variables for fibromyalgia, b) to analyze predictive variables for alexithymia.

In particular, the manuscript presents two clearly differentiated analyses. One of them, directly associated to the aim of the manuscript, focuses on the differences between alexithymia, attachment, parental bonding and anxiety and depression in FM and HC by means of bivariate analyses and logistic regression. The other, with no association with the main aim, but having used the same method, uses the same analyses, in this case to analyze the differences between participants with and without alexithymia (with the total sample). There is a need to justify this analysis within the general aim of the study. In this context, and as the authors have pointed out (“the present report represents a unique and different contribution, as we have never evaluated before attachment styles and the association with alexithymia in patients with FM” (lines 349-351), the novelty of the manuscript is lost as it actually tackles two independent aims that have been widely reported in previous literature.

The methods should have been adapted, in particular the statistical analyses, so as to put both together (a and b). One possibility could be to include the condition (FM/HC) as a predictive or moderating variable (depending on which aim is being pursued) in the second regression analysis (alexithymia vs no alexithymia).

The following suggestions and modifications should also be considered:

1) To delete the phrase “No previous study has been published yet, using the present dataset” from the measures section (line 123-124).

2) It would be of interest to specify the Cronbach’s alphas obtained from the sample.

3) There is no justification for the inclusion of the anxiety and depression measures as part of the study. The justification hasn’t been sufficiently well argued: “we decided to include also psychological distress variables into the model, considering the prominent role that these factors play in the symptomatology of patients with FM” (lines 197-198). Furthermore, the HADS was used as a measure for psychological distress, and it was later included as a measure for anxiety and depression.

4) There is little clarity regarding the measure used to assess the sample’s educational level. Table 1 states “Educational level (years)”. Given that this is not a usual measure for educational level, what it actually means should be specified in the instruments section.

5) Why was there no suggestion of a sample of healthy participants to match the fibromyalgia patients for age and educational level so to be able to ensure more homogeneity for these variables? Although no statistically significant differences were found, they are close to significance.

6) Were there any statistically significant differences in relation to marriage status or educational level between FM and HC? Chi-square analyses and p. values are missing in Table 1.

7) Please indicate in the text (lines 231-234) the contrast statistic (chi-square) and the p. values for the differences in the proportion of alexithymia between the FM and HC groups.

8) In the discussion, there is no need to comment on the association between parenting styles and other chronic diseases which are not fibromyalgia (lines 367-374). There should be further discussion regarding the results in relation to fibromyalgia populations.

9) In relation to the comment on lines 392-393 “Contrary to our expectations, neither parental bonding nor attachment styles significantly predicted group membership (i.e. patients with FM vs. HC)”, further discussion of this result is required. It is possible that having introduced symptoms (anxiety and depression) as predictive variables could have concealed the role that other variables of interest might have played. The method should be adapted, in particular the statistical analyses, for this limitation, and should include the use of symptom variables as possible modulators and not as predictors.

10) In Model 2 (line 272) “In Model 2, the TAS-20 total and subscale scores were entered as predictors”, only dimensions and not total TAS-20 scores should have been included so to avoid co-linearity problems that could affect results. In fact, one of the dimensions included in the total TAS-20 (“externally oriented thinking”) has not been shown to be an explanatory variable in this study, nor in any other previous studies either.

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Reviewer #1: No

Reviewer #2: No

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25 Mar 2020

Turin, 25 March 2020

Ref: PONE-D-20-01350R1

Title: Attachment style and parental bonding: relationships with fibromyalgia and alexithymia

Journal: PLOS ONE

Dear Dr. Juan V. Luciano,

many thanks for the opportunity to resubmit the above manuscript to “PlOS ONE” journal. We are very grateful for the thorough, insightful reviews and we have modified the paper taking into account all these suggestions. Please, you can find below a point-by-point response to all the reviewers’ comments, in Italic the referee comments; in bold the authors’ responses. Modifications in the text have been highlighted in yellow.

Waiting for your gentle reply,

Yours Sincerely

Annunziata Romeo

Editor’s Comments

Dear Dr Romeo,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Thank you for the opportunity to consider our manuscript for publication.

Reviewers’ Comments to Authors

Reviewer 1

Introduction.

Two recently published studies reported a higher prevalence of alexithymia in people with Fibromyalgia (48%-64%) than those reported in the introduction. It would be convenient to update this information.

References:

1. Front Psychol. 2019 Jul 31; 10: 1735. DOI: 10.3389/fpsyg.2019.01735.

2. Clin Exp Rheumatol 2019 Oct 9[Online ahead of print]

Thank you for your comments. Following your suggestions, we updated the prevalence of alexithymia in patients with Fibromyalgia (FM), according to this new evidence.

Methods

1) A medical expert in the field made the diagnosis of Fibromyalgia. However, it is not clear if the doctor used any classification criteria (for example, ACR criteria 1990, 2010 or 2016) to unify the standards in the diagnosis in the sample. I consider it appropriate to clarify in the methods section.

Thank you for your comment. For the diagnosis of FM, the rheumatologists used the ACR criteria of 2010. Following your suggestion, we added this information in the ‘Participants and procedure’ section.

2) Something to complement the description of the sample is if the center where the investigation was carried out, any patient with pain can go to the center (Primary Healthcare), or for their attention, the evaluation and referral of another doctor are necessary (Secondary / Tertiary Health Care).

Thank you for your observation. The usual practice for our center requires that firstly the general practitioner refers the patients to the rheumatologist, so that he/she can ascertain whether the diagnosis of FM may be done. After the diagnosis of FM has been confirmed, the rheumatologist usually refers the patients to the psychiatrist and psychologist, who in turn provide patients with the pharmacological treatment and the psychological support.

3) There is duplicate information; for example, page 5, lines 106 and 112, repeat the time of inclusion of patients. The exclusion criteria are the same for both groups, with the exception that in the control group, patients with rheumatic diseases or chronic pain are excluded. I recommend presenting them in the same paragraph.

Thank you for your comments. Following your suggestions, we made the required changes to the ‘Participants and procedure’ section.

Results

1) In the manuscript, there is any inconsistency between the number of people with fibromyalgia included. In the methods section, one hundred and seven patients report. In the headings of Table 1 and Table 2, 100 patients are reported. However, the sum of the variable's marital status and occupation includes only 99 patients. This information should be reviewed.

We appreciate this remark being pointed out to us. A total sample of 100 patients with FM was recruited for the present study. However, regarding the marital status, there has been a missing value and so the sum is 99 patients. For what concern, instead, both the ‘Participants and procedure’ section and the occupation, an error has occurred during the transcription of the data. We have now corrected the mistake in both parts.

2) There is information that suggests gender differences in the prevalence of alexithymia. Because of the higher frequency of fibromyalgia in women, some studies only include women. The manuscript does not present the percentage of women involved in each of the groups. This information should be clarified.

Thank you for your observation. As indicated in the ‘Participants and procedure’ section, both the FM and HC groups consist entirely of women. Therefore, no percentage for gender has been reported.

3) Page 11, line 220. Consider changing the word "composite" to "total score" or "global score." Which better reflects the score of the 20 items on the TAS-20 scale.

Thank you for your comment. Following your suggestion, we changed the word ‘composite’ to ‘total score’ for the TAS-20.

Conclusions

In the conclusions, I suggest removing "In spite of these limitations".

Thank you for your observation. Following your suggestion, we removed ‘In spite of these limitations’ at the beginning of the conclusions.

Reviewer: 2

Comments to the Author

This article focuses on a particular area of interest, specifically “to examine the associations between attachment styles, parental bonding, and alexithymia among patients with fibromyalgia (FM) and healthy controls (HC)” (lines 22-24), nevertheless the method employed makes it look as if it were two independent studies with no apparent link, as if they weren’t connected enough to be part of the same manuscript: a) to analyze predictive variables for fibromyalgia, b) to analyze predictive variables for alexithymia.

In particular, the manuscript presents two clearly differentiated analyses. One of them, directly associated to the aim of the manuscript, focuses on the differences between alexithymia, attachment, parental bonding and anxiety and depression in FM and HC by means of bivariate analyses and logistic regression. The other, with no association with the main aim, but having used the same method, uses the same analyses, in this case to analyze the differences between participants with and without alexithymia (with the total sample). There is a need to justify this analysis within the general aim of the study. In this context, and as the authors have pointed out (“the present report represents a unique and different contribution, as we have never evaluated before attachment styles and the association with alexithymia in patients with FM” (lines 349-351), the novelty of the manuscript is lost as it actually tackles two independent aims that have been widely reported in previous literature.

The methods should have been adapted, in particular the statistical analyses, so as to put both together (a and b). One possibility could be to include the condition (FM/HC) as a predictive or moderating variable (depending on which aim is being pursued) in the second regression analysis (alexithymia vs no alexithymia).

Thank you for your comments and appreciation.

The present study had a twofold aim, as we reported in the following lines of the introductive section: “The present study aimed to examine deeply the associations between attachment styles, parental bonding, and alexithymia among patients with FM and healthy controls (HC). Particularly, we aimed to discern if parental bonding and adult attachment styles might play a key role in predicting group membership (i.e. patients with FM vs. HC) or otherwise if these variables could only predict the likelihood of having alexithymia.” Indeed, we wanted to test two different but related hypotheses. The first unexplored goal was to investigate if parental bonding and adult attachment styles might play a key role in predicting group membership (i.e. patients with FM vs. HC), while the second objective, based on some previous studies, was to assess if parental bonding and adult attachment styles could only predict the likelihood of having alexithymia, regardless of the presence of FM per se.

For what concern the following sentence, ‘The present report represents a unique and different contribution, as we have never evaluated before attachment styles and the association with alexithymia in patients with FM’, it has to be noted that it was not present in the original version of the manuscript we submitted. After a preliminary revision made by the PLOS ONE editorial board, we were asked to indicate the differences and novelties of the present study with respect to our previous articles on FM (e.g. references [8; 14; 51-53]). However, in order to integrate better this paragraph with the twofold aim of our study, we slightly modified this part in the text (please, see lines 328-331).

Regarding the second logistic regression analysis, we appreciate your suggestions to improve the methods section of our article. However, after careful consideration, we have thought that adding the variable ‘group’ (FM vs. HC) into the regression model, would not have been in line with the two above-outlined aims of our study. Indeed, we wanted to assess two different goals, the first one concerning the comparison between patients with FM and HC, whereas the second one relating to the comparison between alexithymic vs. non-alexithymic participants. Moreover, our group of FM patients, in line with the available evidence, reported significantly higher levels of alexithymia compared to the healthy women (35% of the FM patients vs. 8.4% of the HC scored above the TAS-20 cut-off); therefore, it is reasonable to assume that the variable ‘group’ might be a significant predictor in the final regression model, taking into account also the results of the first logistic analysis we performed (the only significant predictors in the final model were found to be the DIF and the DDF factors of the TAS-20).

The following suggestions and modifications should also be considered:

1) To delete the phrase “No previous study has been published yet, using the present dataset” from the measures section (line 123-124).

Thank you for your comment. We may not delete this sentence, as we were asked to insert this specification following the preliminary revision made by the PLOS ONE editorial board.

2) It would be of interest to specify the Cronbach’s alphas obtained from the sample.

Thank you for your comment. We totally agree with you that it would have been more appropriate to report our own Cronbach’s alfa coefficients in the manuscript. However, we have some troubles in recovering the patients’ responses to the single items of the measures we employed. Indeed, we have administered all paper-and-pencil questionnaires and in the final dataset we have only the total scores for the different scales and subscales (we did not report the values for each item, as we used all validated and reliable instruments). The difficulties in recovering the patients’ responses are due to the impossibility to access to the questionnaires records as a consequence of the covid-19 health emergency. Indeed, the archives are located at the “Città della salute e della scienza” hospital of Turin, Italy. As a result, it would take months to retrieve all the necessary information for computing the Cronbach’s alfa coefficients on our data.

For this reason, we reported the Cronbach’s alfa coefficients from previous studies, which examined the psychometric properties of these instruments, in order to highlight their reliability and validity.

3) There is no justification for the inclusion of the anxiety and depression measures as part of the study. The justification hasn’t been sufficiently well argued: “we decided to include also psychological distress variables into the model, considering the prominent role that these factors play in the symptomatology of patients with FM” (lines 197-198). Furthermore, the HADS was used as a measure for psychological distress, and it was later included as a measure for anxiety and depression.

Thank you for your observations. Following your insightful remark, we decided to remove anxiety and depression measures from our analyses.

4) There is little clarity regarding the measure used to assess the sample’s educational level. Table 1 states “Educational level (years)”. Given that this is not a usual measure for educational level, what it actually means should be specified in the instruments section.

Thank you for your comment. We are aware that this is not a usual measure for the educational level. However, in order to obtain a continuous variable that could be easily used for data analyses, we asked our participants to indicate the total of how many years of education they achieved. In order to make this information clearer, we provided more details about the way educational level was assessed in the measures section (please, see ‘Sociodemographic and clinical information’ paragraph).

5) Why was there no suggestion of a sample of healthy participants to match the fibromyalgia patients for age and educational level so to be able to ensure more homogeneity for these variables? Although no statistically significant differences were found, they are close to significance.

Thank you for your observation. We recruited healthy participants that were matched for demographic characteristics (i.e. age, gender, and educational level) to the FM patients. Following your suggestions, we specified better this information in the text (please, see ‘Participants and procedure’ and ‘Results’ sections).

6) Were there any statistically significant differences in relation to marriage status or educational level between FM and HC? Chi-square analyses and p. values are missing in Table 1.

Thank you for your comment. Following your suggestions, we added these results in Table 1.

7) Please indicate in the text (lines 231-234) the contrast statistic (chi-square) and the p. values for the differences in the proportion of alexithymia between the FM and HC groups.

Thank you for your comment. Following your suggestion, we added these results in the text.

8) In the discussion, there is no need to comment on the association between parenting styles and other chronic diseases which are not fibromyalgia (lines 367-374). There should be further discussion regarding the results in relation to fibromyalgia populations.

Thank you for your observation. We included also studies carried out in different chronic pain populations, as only a limited number of studies is available in patients with FM (Gil et al., 2008; Peñacoba et al., 2018). Considering the sparse results on the topic, the first aim of the present study was exactly to shed light on the association between attachment variables and FM.

9) In relation to the comment on lines 392-393 “Contrary to our expectations, neither parental bonding nor attachment styles significantly predicted group membership (i.e. patients with FM vs. HC)”, further discussion of this result is required. It is possible that having introduced symptoms (anxiety and depression) as predictive variables could have concealed the role that other variables of interest might have played. The method should be adapted, in particular the statistical analyses, for this limitation, and should include the use of symptom variables as possible modulators and not as predictors.

Thank you for your comments. Following your suggestions, we removed anxiety and depression measures (i.e. HADS A-D) from our analyses. However, the results of the first logistic regression we performed only slightly changed after removing the HADS A and D from the analysis. Indeed, once again the only significant predictor in the final model was found to be alexithymia (in this case both DIF and DDF factors of the TAS-20).

10) In Model 2 (line 272) “In Model 2, the TAS-20 total and subscale scores were entered as predictors”, only dimensions and not total TAS-20 scores should have been included so to avoid co-linearity problems that could affect results. In fact, one of the dimensions included in the total TAS-20 (“externally oriented thinking”) has not been shown to be an explanatory variable in this study, nor in any other previous studies either.

We appreciate this remark being pointed out to us. Following your suggestion, we removed the TAS-20 total score from the first logistic regression analysis (please, see Table 3 for details).

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

26 Mar 2020

PONE-D-20-01350R2

Attachment style and parental bonding: relationships with fibromyalgia and alexithymia

PLOS ONE

Dear Dr Romeo,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

We would appreciate receiving your revised manuscript by May 10 2020 11:59PM. When you are ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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We look forward to receiving your revised manuscript.

Kind regards,

Juan V. Luciano, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (if provided):

Dear authors,

I think you have correctly addressed all reviewers' concerns. Congratulations.

Notwithstanding, I encourage you to more deeply elaborate this idea in your discussion of results:

"First, when working with patients with FM, clinical attention should be paid to not only the management of pain symptoms but also impairments in affect regulation and attachment dynamics".

Your conclusion might have some link with the results of this recently published pilot RCT: Cost-Utility of Attachment-Based Compassion Therapy (ABCT) for Fibromyalgia Compared to Relaxation: A Pilot Randomized Controlled Trial - https://www.ncbi.nlm.nih.gov/pubmed/32156065

Sincerely,

Dr. Luciano

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27 Mar 2020

Turin, 25 March 2020

Ref: PONE-D-20-01350R1

Title: Attachment style and parental bonding: relationships with fibromyalgia and alexithymia

Journal: PLOS ONE

Dear Dr. Juan V. Luciano,

many thanks for the opportunity to resubmit the above manuscript to “PlOS ONE” journal. We are very grateful for the thorough, insightful reviews and we have modified the paper taking into account all these suggestions. Please, you can find below a point-by-point response to all the reviewers’ comments, in Italic the referee comments; in bold the authors’ responses. Modifications in the text have been highlighted in yellow.

Waiting for your gentle reply,

Yours Sincerely

Annunziata Romeo

Editor’s Comments

Dear Dr Romeo,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Thank you for the opportunity to consider our manuscript for publication.

Reviewers’ Comments to Authors

Reviewer 1

Introduction.

Two recently published studies reported a higher prevalence of alexithymia in people with Fibromyalgia (48%-64%) than those reported in the introduction. It would be convenient to update this information.

References:

1. Front Psychol. 2019 Jul 31; 10: 1735. DOI: 10.3389/fpsyg.2019.01735.

2. Clin Exp Rheumatol 2019 Oct 9[Online ahead of print]

Thank you for your comments. Following your suggestions, we updated the prevalence of alexithymia in patients with Fibromyalgia (FM), according to this new evidence.

Methods

1) A medical expert in the field made the diagnosis of Fibromyalgia. However, it is not clear if the doctor used any classification criteria (for example, ACR criteria 1990, 2010 or 2016) to unify the standards in the diagnosis in the sample. I consider it appropriate to clarify in the methods section.

Thank you for your comment. For the diagnosis of FM, the rheumatologists used the ACR criteria of 2010. Following your suggestion, we added this information in the ‘Participants and procedure’ section.

2) Something to complement the description of the sample is if the center where the investigation was carried out, any patient with pain can go to the center (Primary Healthcare), or for their attention, the evaluation and referral of another doctor are necessary (Secondary / Tertiary Health Care).

Thank you for your observation. The usual practice for our center requires that firstly the general practitioner refers the patients to the rheumatologist, so that he/she can ascertain whether the diagnosis of FM may be done. After the diagnosis of FM has been confirmed, the rheumatologist usually refers the patients to the psychiatrist and psychologist, who in turn provide patients with the pharmacological treatment and the psychological support.

3) There is duplicate information; for example, page 5, lines 106 and 112, repeat the time of inclusion of patients. The exclusion criteria are the same for both groups, with the exception that in the control group, patients with rheumatic diseases or chronic pain are excluded. I recommend presenting them in the same paragraph.

Thank you for your comments. Following your suggestions, we made the required changes to the ‘Participants and procedure’ section.

Results

1) In the manuscript, there is any inconsistency between the number of people with fibromyalgia included. In the methods section, one hundred and seven patients report. In the headings of Table 1 and Table 2, 100 patients are reported. However, the sum of the variable's marital status and occupation includes only 99 patients. This information should be reviewed.

We appreciate this remark being pointed out to us. A total sample of 100 patients with FM was recruited for the present study. However, regarding the marital status, there has been a missing value and so the sum is 99 patients. For what concern, instead, both the ‘Participants and procedure’ section and the occupation, an error has occurred during the transcription of the data. We have now corrected the mistake in both parts.

2) There is information that suggests gender differences in the prevalence of alexithymia. Because of the higher frequency of fibromyalgia in women, some studies only include women. The manuscript does not present the percentage of women involved in each of the groups. This information should be clarified.

Thank you for your observation. As indicated in the ‘Participants and procedure’ section, both the FM and HC groups consist entirely of women. Therefore, no percentage for gender has been reported.

3) Page 11, line 220. Consider changing the word "composite" to "total score" or "global score." Which better reflects the score of the 20 items on the TAS-20 scale.

Thank you for your comment. Following your suggestion, we changed the word ‘composite’ to ‘total score’ for the TAS-20.

Conclusions

In the conclusions, I suggest removing "In spite of these limitations".

Thank you for your observation. Following your suggestion, we removed ‘In spite of these limitations’ at the beginning of the conclusions.

Reviewer: 2

Comments to the Author

This article focuses on a particular area of interest, specifically “to examine the associations between attachment styles, parental bonding, and alexithymia among patients with fibromyalgia (FM) and healthy controls (HC)” (lines 22-24), nevertheless the method employed makes it look as if it were two independent studies with no apparent link, as if they weren’t connected enough to be part of the same manuscript: a) to analyze predictive variables for fibromyalgia, b) to analyze predictive variables for alexithymia.

In particular, the manuscript presents two clearly differentiated analyses. One of them, directly associated to the aim of the manuscript, focuses on the differences between alexithymia, attachment, parental bonding and anxiety and depression in FM and HC by means of bivariate analyses and logistic regression. The other, with no association with the main aim, but having used the same method, uses the same analyses, in this case to analyze the differences between participants with and without alexithymia (with the total sample). There is a need to justify this analysis within the general aim of the study. In this context, and as the authors have pointed out (“the present report represents a unique and different contribution, as we have never evaluated before attachment styles and the association with alexithymia in patients with FM” (lines 349-351), the novelty of the manuscript is lost as it actually tackles two independent aims that have been widely reported in previous literature.

The methods should have been adapted, in particular the statistical analyses, so as to put both together (a and b). One possibility could be to include the condition (FM/HC) as a predictive or moderating variable (depending on which aim is being pursued) in the second regression analysis (alexithymia vs no alexithymia).

Thank you for your comments and appreciation.

The present study had a twofold aim, as we reported in the following lines of the introductive section: “The present study aimed to examine deeply the associations between attachment styles, parental bonding, and alexithymia among patients with FM and healthy controls (HC). Particularly, we aimed to discern if parental bonding and adult attachment styles might play a key role in predicting group membership (i.e. patients with FM vs. HC) or otherwise if these variables could only predict the likelihood of having alexithymia.” Indeed, we wanted to test two different but related hypotheses. The first unexplored goal was to investigate if parental bonding and adult attachment styles might play a key role in predicting group membership (i.e. patients with FM vs. HC), while the second objective, based on some previous studies, was to assess if parental bonding and adult attachment styles could only predict the likelihood of having alexithymia, regardless of the presence of FM per se.

For what concern the following sentence, ‘The present report represents a unique and different contribution, as we have never evaluated before attachment styles and the association with alexithymia in patients with FM’, it has to be noted that it was not present in the original version of the manuscript we submitted. After a preliminary revision made by the PLOS ONE editorial board, we were asked to indicate the differences and novelties of the present study with respect to our previous articles on FM (e.g. references [8; 14; 51-53]). However, in order to integrate better this paragraph with the twofold aim of our study, we slightly modified this part in the text (please, see lines 328-331).

Regarding the second logistic regression analysis, we appreciate your suggestions to improve the methods section of our article. However, after careful consideration, we have thought that adding the variable ‘group’ (FM vs. HC) into the regression model, would not have been in line with the two above-outlined aims of our study. Indeed, we wanted to assess two different goals, the first one concerning the comparison between patients with FM and HC, whereas the second one relating to the comparison between alexithymic vs. non-alexithymic participants. Moreover, our group of FM patients, in line with the available evidence, reported significantly higher levels of alexithymia compared to the healthy women (35% of the FM patients vs. 8.4% of the HC scored above the TAS-20 cut-off); therefore, it is reasonable to assume that the variable ‘group’ might be a significant predictor in the final regression model, taking into account also the results of the first logistic analysis we performed (the only significant predictors in the final model were found to be the DIF and the DDF factors of the TAS-20).

The following suggestions and modifications should also be considered:

1) To delete the phrase “No previous study has been published yet, using the present dataset” from the measures section (line 123-124).

Thank you for your comment. We may not delete this sentence, as we were asked to insert this specification following the preliminary revision made by the PLOS ONE editorial board.

2) It would be of interest to specify the Cronbach’s alphas obtained from the sample.

Thank you for your comment. We totally agree with you that it would have been more appropriate to report our own Cronbach’s alfa coefficients in the manuscript. However, we have some troubles in recovering the patients’ responses to the single items of the measures we employed. Indeed, we have administered all paper-and-pencil questionnaires and in the final dataset we have only the total scores for the different scales and subscales (we did not report the values for each item, as we used all validated and reliable instruments). The difficulties in recovering the patients’ responses are due to the impossibility to access to the questionnaires records as a consequence of the covid-19 health emergency. Indeed, the archives are located at the “Città della salute e della scienza” hospital of Turin, Italy. As a result, it would take months to retrieve all the necessary information for computing the Cronbach’s alfa coefficients on our data.

For this reason, we reported the Cronbach’s alfa coefficients from previous studies, which examined the psychometric properties of these instruments, in order to highlight their reliability and validity.

3) There is no justification for the inclusion of the anxiety and depression measures as part of the study. The justification hasn’t been sufficiently well argued: “we decided to include also psychological distress variables into the model, considering the prominent role that these factors play in the symptomatology of patients with FM” (lines 197-198). Furthermore, the HADS was used as a measure for psychological distress, and it was later included as a measure for anxiety and depression.

Thank you for your observations. Following your insightful remark, we decided to remove anxiety and depression measures from our analyses.

4) There is little clarity regarding the measure used to assess the sample’s educational level. Table 1 states “Educational level (years)”. Given that this is not a usual measure for educational level, what it actually means should be specified in the instruments section.

Thank you for your comment. We are aware that this is not a usual measure for the educational level. However, in order to obtain a continuous variable that could be easily used for data analyses, we asked our participants to indicate the total of how many years of education they achieved. In order to make this information clearer, we provided more details about the way educational level was assessed in the measures section (please, see ‘Sociodemographic and clinical information’ paragraph).

5) Why was there no suggestion of a sample of healthy participants to match the fibromyalgia patients for age and educational level so to be able to ensure more homogeneity for these variables? Although no statistically significant differences were found, they are close to significance.

Thank you for your observation. We recruited healthy participants that were matched for demographic characteristics (i.e. age, gender, and educational level) to the FM patients. Following your suggestions, we specified better this information in the text (please, see ‘Participants and procedure’ and ‘Results’ sections).

6) Were there any statistically significant differences in relation to marriage status or educational level between FM and HC? Chi-square analyses and p. values are missing in Table 1.

Thank you for your comment. Following your suggestions, we added these results in Table 1.

7) Please indicate in the text (lines 231-234) the contrast statistic (chi-square) and the p. values for the differences in the proportion of alexithymia between the FM and HC groups.

Thank you for your comment. Following your suggestion, we added these results in the text.

8) In the discussion, there is no need to comment on the association between parenting styles and other chronic diseases which are not fibromyalgia (lines 367-374). There should be further discussion regarding the results in relation to fibromyalgia populations.

Thank you for your observation. We included also studies carried out in different chronic pain populations, as only a limited number of studies is available in patients with FM (Gil et al., 2008; Peñacoba et al., 2018). Considering the sparse results on the topic, the first aim of the present study was exactly to shed light on the association between attachment variables and FM.

9) In relation to the comment on lines 392-393 “Contrary to our expectations, neither parental bonding nor attachment styles significantly predicted group membership (i.e. patients with FM vs. HC)”, further discussion of this result is required. It is possible that having introduced symptoms (anxiety and depression) as predictive variables could have concealed the role that other variables of interest might have played. The method should be adapted, in particular the statistical analyses, for this limitation, and should include the use of symptom variables as possible modulators and not as predictors.

Thank you for your comments. Following your suggestions, we removed anxiety and depression measures (i.e. HADS A-D) from our analyses. However, the results of the first logistic regression we performed only slightly changed after removing the HADS A and D from the analysis. Indeed, once again the only significant predictor in the final model was found to be alexithymia (in this case both DIF and DDF factors of the TAS-20).

10) In Model 2 (line 272) “In Model 2, the TAS-20 total and subscale scores were entered as predictors”, only dimensions and not total TAS-20 scores should have been included so to avoid co-linearity problems that could affect results. In fact, one of the dimensions included in the total TAS-20 (“externally oriented thinking”) has not been shown to be an explanatory variable in this study, nor in any other previous studies either.

We appreciate this remark being pointed out to us. Following your suggestion, we removed the TAS-20 total score from the first logistic regression analysis (please, see Table 3 for details).

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

30 Mar 2020

Attachment style and parental bonding: relationships with fibromyalgia and alexithymia

PONE-D-20-01350R3

Dear Dr. Romeo,

We are pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it complies with all outstanding technical requirements.

Within one week, you will receive an e-mail containing information on the amendments required prior to publication. When all required modifications have been addressed, you will receive a formal acceptance letter and your manuscript will proceed to our production department and be scheduled for publication.

Shortly after the formal acceptance letter is sent, an invoice for payment will follow. To ensure an efficient production and billing process, please log into Editorial Manager at https://www.editorialmanager.com/pone/, click the "Update My Information" link at the top of the page, and update your user information. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to enable them to help maximize its impact. If they will be preparing press materials for this manuscript, you must inform our press team as soon as possible and no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

With kind regards,

Juan V. Luciano, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

31 Mar 2020

PONE-D-20-01350R3

Attachment style and parental bonding: relationships with fibromyalgia and alexithymia

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