Loneliness among people with severe mental illness during the COVID-19 pandemic: Results from a linked UK population cohort study.

AIM/GOAL/
PURPOSE: Population surveys underrepresent people with severe mental ill health. This paper aims to use multiple regression analyses to explore perceived social support, loneliness and factor associations from self-report survey data collected during the Covid-19 pandemic in a sample of individuals with severe mental ill health. DESIGN/METHODOLOGY/APPROACH: We sampled an already existing cohort of people with severe mental ill health. Researchers contacted participants by phone or by post to invite them to take part in a survey about how the pandemic restrictions had impacted health, Covid-19 experiences, perceived social support, employment and loneliness. Loneliness was measured by the three item UCLA loneliness scale.
FINDINGS: In the pandemic sub-cohort, 367 adults with a severe mental ill health diagnosis completed a remote survey. 29-34% of participants reported being lonely. Loneliness was associated with being younger in age (adjusted OR = -.98, p = .02), living alone (adjusted OR = 2.04, p = .01), high levels of social and economic deprivation (adjusted OR = 2.49, p = .04), and lower perceived social support (B = -5.86, p < .001). Living alone was associated with lower perceived social support. Being lonely was associated with a self-reported deterioration in mental health during the pandemic (adjusted OR = 3.46, 95%CI 2.03-5.91). PRACTICAL IMPLICATIONS: Intervention strategies to tackle loneliness in the severe mental ill health population are needed. Further research is needed to follow-up the severe mental ill health population after pandemic restrictions are lifted to understand perceived social support and loneliness trends. ORIGINALITY: Loneliness was a substantial problem for the severe mental ill health population before the Covid-19 pandemic but there is limited evidence to understand perceived social support and loneliness trends during the pandemic.

Introduction

Loneliness is increasingly recognised as a risk to mental and physical health [1], and there is evidence that levels of reported loneliness have increased during the Covid-19 pandemic [2]. Public health measures, such as physical distancing and ‘shielding’ (self-isolation to reduce transmission risk) has impacted the lives of the UK population. People who felt most lonely before the pandemic reported even greater loneliness after four months of lockdown [2]. However, the effects of the pandemic restrictions on the severe mental ill health (SMI) population is unknown. Loneliness is a substantial problem among people with SMI, such as bipolar or psychotic disorders, but there is limited evidence to understand the extent of loneliness and related factors in this population. Australian epidemiological studies estimate that 76–80% of people with psychosis-spectrum disorders are lonely [3, 4] which is 2.3 times higher than in the general population. However, there is no known prevalence estimates based on the UK SMI population before or during the pandemic.

Existing evidence highlights the importance of tackling loneliness in SMI. In the general population, loneliness severity is a predictor for early mortality [5, 6] and is equivalent to the health risks posed by smoking or physical inactivity [7]. In schizophrenia, loneliness is a significant contributor to lower quality of life [8, 9] and is associated with a range of negative effects, such as internalised stigma [10], lower self-esteem and self-efficacy for living in the community [11], increased symptoms of paranoia [12, 13], and increased problems such as depression [14], anxiety, and hypertension [13]. People with SMI who feel lonely are 2.69 times more likely to be admitted to inpatient psychiatric care [15].

Perceived social support (PSS) is how an individual perceives friends, family, and others as sources of material, psychological, and general support during times of need. Greater PSS is an important protective factor against loneliness. A systematic review found preliminary evidence that lower PSS is associated with worse social functioning and quality of life outcomes among people with schizophrenia and bipolar disorder [16]. In a US schizophrenia sample, greater PSS was associated with higher social functioning scores but not global functioning [16]. Lower PSS in bipolar disorder was associated with greater depression, lower functioning, and longer recovery times.

People with SMI experience additional barriers to social connectivity. Increased social stigma [17, 18], challenges presented by clinical symptoms [18], and sociodemographic factors such as greater poverty and lower likelihood of being married or in employment [19, 20] all contribute to greater loneliness among people with psychosis-spectrum disorders. It is believed that loneliness both results from, and contributes to, psychotic symptoms [21, 22]. This suggests that SMI can reduce factors such as social support which then contributes to greater loneliness. This increased loneliness can then worsen the severity of psychotic symptoms which further reduces social support [23], leading to a difficult cycle.

Being employed can be a protective factor against loneliness [24]. One study about people with schizophrenia found that being employed was associated with greater social participation but was not associated with loneliness [17]. For people with schizophrenia, reduced financial resources could elicit feelings of shame in social encounters and not being employed can contribute to feelings of social inferiority [17]. Pre-Covid reduced employment rates among those with schizophrenia [19] could limit the protective benefits of employment on loneliness. It is not known how the pandemic may have affected employment for people with SMI.

Given the importance of loneliness as a threat to public health, and the impacts of COVID on levels of loneliness in the population, it remains important to study loneliness and associated among people with SMI. Despite the abundance of surveys exploring the psychological impacts of COVID it is a significant omission that people with SMI do not participate or are under-represented. In this study we explore the impacts of COVID restrictions on loneliness in a large clinical cohort of people with SMI.

Methods

Design

The Closing the Gap (CtG) study is a large (n = 9, 914) transdiagnostic clinical cohort recruited between April 2016 and March 2020. Participants have documented diagnoses of schizophrenia or delusional/psychotic illness (ICD 10 F20.X & F22.X or DSM equivalent) or bipolar disorder (ICD F31.X or DSM-equivalent). The composition of the CtG cohort has previously been described [25].

We were funded to explore the impact of the COVID-19 pandemic in a sub-section of the CtG clinical cohort and we identified participants for Optimising Well-being in Self-Isolation study (OWLS) (https://sites.google.com/york.ac.uk/owls-study/home). Recruitment and data collection to the OWLS study took place between July and December 2020. To ensure that the OWLS COVID-19 sub-cohort captured a range of demographics we created a sampling framework based on gender, age, ethnicity and whether they were recruited via primary or secondary care. OWLS participants were recruited from 17 mental health trusts and six Clinical Research Networks across urban and rural settings in England.

Recruitment and participants

Ethical approval was granted by the Health Research Authority North West–Liverpool Central Research Ethics Committee (REC reference 20/NW/0276). To be eligible to take part in OWLS COVID-19 study, people had to be aged 18 or over, have a recorded SMI diagnosis, to have taken part in CtG study, and have consented to be contacted again to be invited to further research. This enabled us to create longitudinal data linkage and to rapidly identify participants during the COVID-19 pandemic.

Materials

The OWLS survey took approximately 40 minutes to complete. Where possible we sought alignment of measures with a large population survey which tracked the impact of COVID on mental health [26], and with the Office of National Statistics (ONS).

Perceived social support

The brief form of the Perceived Social Support Questionnaire (F-SozU K6) measures perceived social support in epidemiological contexts [27]. The six items are included in the OWLS survey and ask to what extent participants have experienced social support within the past two weeks. Scores were added to provide a total score ranging from 6 to 30, where a higher score indicates greater perceived social support.

Loneliness

Loneliness was measured using the University of California, Los Angeles Loneliness Scale (UCLA-LS) 3-item [28] which asks about loneliness symptoms experienced within the past two weeks and produces a score range of 3–9, where a higher score indicates greater loneliness.

A single item measuring loneliness was also included in the OWLS survey from the Office for National Statistics (ONS) [29] to allow comparison of findings with general population surveys. The item, “How often do you feel lonely?”, had possible answers of “hardly ever”; “some of the time”; or “often”.

Financial status was determined using one item in the OWLS survey, “Compared to before the pandemic restrictions, how would you say you are doing financially right now?”. Responses of “I am better off” or “I am about the same” were coded as not financially worse off, and a response of “I am worse off” was coded as financially worse off. Pre-Covid-19 employment status (e.g. employed full time, student, voluntary work) was obtained from the CtG survey. Current employment status was recorded in the OWLS survey. Participants who were in full- or part-time paid employment, a student, or unpaid volunteers were coded as Professionally active and all other employment statuses were coded as Professionally inactive. Participants were considered to be shielding if they reported in the OWLS study that “I was in full isolation, not leaving my home at all” during the pandemic. Whether or not participants lived alone was determined from one item in the OWLS survey “Who lives with you?”. Self-reported deterioration in mental health was determined using one OWLS survey item, “Compared with life before the beginning of the pandemic restrictions, how would you rate your [mental] health in general?”. Responses of “better than before” or “about the same” were coded as no deterioration and a response of “worse than before” was coded as deterioration.

Index of multiple deprivation

Participant postcodes collected at the point of inception to the CtG study were used to obtain an Index of Multiple Deprivation (IMD)assigned by the Ministry of Housing, Communities and Local Government (https://imd-by-postcode.opendatacommunities.org/imd/2019). Decile scores are given between 1 and 10 and then condensed to give five possible outcomes; very high deprivation (1 and 2), high deprivation (3 and 4), moderate deprivation (5 and 6), low deprivation (7 and 8) and very low deprivation (9 and 10).

Procedure

People who met the eligibility criteria were contacted by telephone or letter and invited to take part in the OWLS COVID-19 study. Those who agreed to take part were provided with three options: i. to carry out the survey over the phone with a researcher; ii. to be sent a link to complete the survey online; or iii. to be sent a hard copy of the questionnaire in the post to complete and return.

Analysis

The study analysis plan was registered on Open Science Framework (available at https://osf.io/e3kdm). The analysis plan incorrectly labelled ‘perceived social support’ as ‘social isolation’. Analyses were undertaken using SPSS v.26. Descriptive statistics were used to describe sociodemographic characteristics, shielding status, perceived social support, and loneliness. Cronbach’s alpha was used to measure internal consistency of the UCLA-LS.

To examine the associations between the independent variables (professional activity, being in shielding’ status, and living alone) and perceived social support, we used multiple linear regression and we controlled for age, gender, ethnicity, socioeconomic deprivation and care setting. Although the same analysis was planned also for loneliness, the assumption of heteroscedacity was not met in the linear regression model. Therefore, we derived a binary loneliness variable, where scoring 7 and above on the UCLA-LS was considered to be lonely, and we examined its association with the aforementioned independent variables with a binary logistic regression. Associations of all independent variables with the dependent variable were first examined with a univariable regression analysis. All independent variables were inserted all together at once in the multivariable models.

Results

Between July and December 2020, 367 people were recruited to the OWLS study. Descriptive statistics for the sample’s sociodemographic factors, shielding status, perceived social support, and loneliness are reported in Table 1. Similar rates of being lonely between the UCLA-LS (N = 125, 34.1%) and ONS (feel lonely often, N = 107, 29.2%) indicate that loneliness was measured reliably.

Table 1

Descriptive statistics for sociodemographic factors, shielding status, perceived social support, and loneliness.

Factor	N (%), total n = 367
Gender
Male	187 (51)
Female	174 (47.4)
Transgender	6 (1.6)
Age (mean, range)	50.5 (20–86)
Ethnicity
White British	284 (77.4)
Other white	18 (4.9)
Mixed white / black	5 (1.4)
Mixed white / Asian	5 (1.4)
Other mixed	4 (1.1)
Asian	24 (6.5)
Black	15 (4.1)
Other non-white	12 (3.3)
Index of Multiple Deprivation
Very high deprivation	97 (26.4)
High deprivation	81 (22.1)
Moderate deprivation	67 (18.3)
Low deprivation	55 (15)
Very low deprivation	52 (14.2)
Mental health care setting
Primary care	139 (37.9)
Secondary care	224 (61)
Co-occupancy status
Living alone	154 (42)
Not living alone	208 (56.7)
Shielding status
In full isolation, not leaving home at all	73 (19.9)
Not in full isolation	288 (78.5)
F-SozU K6 Perceived social support (mean, sd)	20.8 (6.4)
UCLA-LS Loneliness
Lonely	125 (34.1)
Not lonely	233 (63.5)
ONS Loneliness
Often	107 (29.2)
Some of the time	129 (35.1)
Hardly ever	122 (33.2)
Professionally active before the pandemic
Yes	123 (33.5)
No	239 (65.1)
Professionally active during the pandemic
Yes	93 (25.3)
No	269 (73.3)
Finance during the pandemic
Being worse off	61 (16.6)
Being better off	60 (16.3)

Perceived social support and loneliness

There was a significant association between occupancy status and perceived social support, with those not living alone reporting greater perceived social support, adjusted B = 3.06, p < .001. Associations are presented in Table 2.

Table 2

Associations between sociodemographic factors and perceived social support.

	Univariable model		Multivariable model		Multiple regression model
	B (standard error)	p	B (standard error)	p	F(12,309) = 2.05, p = .02, R2 = .07
Age	.03 (.02)	.25	.03 (.02)	.2
Gender (ref: male)
Female	.38 (.7)	.59	-.06 (.72)	.93
Transgender	-4.65 (2.9)	.11	-3.47 (2.86)	.23
Ethnic minority	-.25 (.96)	.79	.35 (.99)	.72
IMD (ref: very low)
Very high	-2 (1.11)	.08	-.44 (1.15)	.7
High	-2.23 (1.17)	.06	-.99 (1.19)	.41
Moderate	-2.41 (1.2)	.05	-1.38 (1.21)	.25
Low	-.7 (1.3)	.58	-.26 (1.24)	.84
Currently accessing mental health services	1.26 (.72)	.08	.5 (.74)	.51
Being professionally active	-1.04 (.8)	.195	-.4 I.83)	.63
Shielding	-.27 (.82)	.74	-.48 (.84)	.57
Not living alone	3.06 (.69)	< .001	2.73 (.78)	< .001

The UCLA-LS was found to be highly reliable (3 items; α = .84). Participants were more likely to report being lonely if they were living alone (adjusted OR = 2.04, 95%CI 1.212–3.431, p = .01), living in an area with high IMD (adjusted OR = 2.493, 95%CI 1.044–5.953, p = .04) and being younger in age (adjusted OR = -.98, 95%CI .964-.997, p = .02). Univariate models demonstrated that people were more likely to feel lonely if they were living in areas of very high IMD, however, this was not significantly associated in the adjusted model. Associations are presented in Table 3.

Table 3

Associations between sociodemographic factors and loneliness.

	N (%)		Univariable model		Multivariable model
	Lonely	Not lonely	Odds ratio (95%CI)	p	Adj. Odds ratio (95%CI)	p
Age			.99 (.97–1)	.05	-.98 (.96–1)	.02
Gender
Male	68 (37.4)	114 (62.6)	1.32 (.85–2.05)	.22	1.44 (.88–2.34)	.15
Female	53 (31.2)	117 (68.8)	1		1
Ethnic
minority	108 (36.2)	190 (63.8)	1.44 (.78–2.64)	.24	1.97 (1.01–3.87)	.05
Non-minority	17 (28.3)	43 (71.7)	1		1
Minority
IMD
Very high	35 (36.8)	60 (63.2)	2.39 (1.07–5.36)	.03	1.52 (.64–3.6)	.35
High	34 (43)	45 (57)	3.1 (1.36–7.05)	.01	2.49 (1.04–5.95)	.04
Moderate	43 (65.2)	23 (34.8)	2.19 (.93–5.17)	.07	1.71 (.69–4.23)	.25
Low	17 (32.1)	36 (67.9)	1.94 (.79–4.76)	.15	1.84 (.73–4.62)	.2
Very low	10 (19.6)	41 (80.4)	1		1
Accessing
secondary	81 (36.8)	139 (63.2)	1.23 (.78–1.93)	.37	1 (.6–1.64)	.97
care	44 (32.1)	93 (67.9)	1		1
Yes
No
Professionally active
	28 (30.4)	64 (69.6)	.76 (.46–1.26)	.29	.84 (.47–1.49)	.55
Yes	97 (36.6)	168 (63.4)	1		1
No
Shielding
Yes	33 (37.9)	54 (62.1)	1.19 (.72–1.96)	.5	1.765 (1–3.11)	.5
No	92 (33.9)	179 (66.1)	1		1
Living alone
Yes	66 (43.7)	85 (56.3)	1.98 (1.27–3.08)	.002	2.04 (1.21–3.43)	.01
No	58 (28.2)	148 (71.8)	1		1

Post-hoc analyses

A deterioration in mental health was reported by 148 (40.3%) of participants and no deterioration reported by 210 (57.2%). A logistic regression found that deterioration in mental health, after controlling for age, gender, minority-status, IMD, and care setting (primary vs secondary), was associated with being lonely (adjusted OR = 3.46, 95%CI 2.03–5.91). A multiple linear regression demonstrated that lower perceived social support, after controlling for age, gender, minority-status, IMD, and care setting (primary vs secondary), was associated with being lonely (B = -5.86, p < .001).

Discussion

Loneliness was found to be a substantial problem for people with SMI during the pandemic; around one in three reported being lonely. This is higher than loneliness rates found in the general population during the pandemic (13–18% [30], 27% [31]). Similar patterns emerged between people with SMI and the general population; younger age and living alone were associated with greater loneliness in both populations. Lower PSS was associated with living alone. There were also similar rates of PSS between those with SMI compared to the general population (20.8 present study vs 21.6 [31]) which was associated with reduced loneliness in both studies.

The physical distancing and shielding measures introduced during the pandemic may have negatively impacted on PSS by making it more difficult to maintain social relationships. The similar patterns in loneliness between the present sample and general population could indicate that many factors which contribute to loneliness in the general population may also contribute to loneliness among those with SMI. However, given the existing literature that loneliness is a substantial problem for people with SMI, combined with the high prevalence of loneliness found in the present study, it is clear that loneliness presents a considerable problem to those with SMI. This is concerning given the strong association we found between being lonely and a deterioration in mental health.

Only a minority of participants reported a worsening to their financial wellbeing or reduction in professional activity during the pandemic. This may be because people with SMI were already disproportionately affected by socioeconomic deprivation and unemployment prior to the pandemic. Being professionally active during the pandemic was not significantly associated with PSS nor loneliness. This differs from analyses of UK-based general population studies where being economically inactive was associated with greater risk loneliness during the pandemic [32]. However, the economically-active variable from the general population analysis differed from the present study in that the general population analysis did not consider un-paid voluntary activity as being active. Further research should add context to this finding by exploring whether professional activity types (e.g. competitive paid vs voluntary activity) or settings (e.g. remote vs face-to-face working) are associated with PSS or loneliness.

Data collection occurred (Jul–Dec 2020) during continual changes to government Covid-19 policies that included both restrictions to non-essential activity and physical distancing, and also easing of restrictions and encouragement for the public to dine out in restaurants. It therefore appears most appropriate to consider the present findings in relation to an early-to-middle phase of the pandemic. Therefore, some long-term effects of the pandemic restrictions and social isolation may have influenced the present findings, but the full long-term effects were likely not felt by the time of data collection. It is important to follow-up participants into a later stage of the pandemic, and as restrictions are lifted, to explore how the long-term effects of the pandemic and restrictions affect loneliness and social isolation. It is concerning that long-term social isolation may make it more difficult to maintain relationships, thereby reducing PSS, and contribute to long-term loneliness and making it more difficult to people to return to normal post-pandemic.

Access to the internet has facilitated social communication for many during the physical distancing restrictions. However, it is not known what portion of the SMI population have access to the internet or how they interact with the internet for social communication. The OWLS study has also explored the use of the internet and found that the majority of the present sample were limited, or non-, users of digital devices, potentially because of a lack of skills or interest [33]. This limited internet access could therefore be contributing to greater loneliness experienced during the pandemic. Further study should explore whether digital interventions in this population are a viable means of improving PSS and reducing loneliness among those with SMI, particularly when face-to-face communication is limited.

Limitations

It would have been preferable to have a pre-Covid profile of the measured variables, but this was a cross-sectional study so there was no pre-Covid baseline measure. It was therefore not possible to understand changes to loneliness during the pandemic. We plan to track trends in the measured variables over time to see the longitudinal course.

The shielding variable did not account for individuals who were shielding and living alone, compared to those who were shielding and not living alone. This may account for the lack of association between shielding and PSS or loneliness.

Loneliness and PSS may have varied between participants with bipolar disorder and psychosis spectrum disorder due to the effects of the disorders. However, this study only explored SMI as a group and future study should explore potential variations in findings between diagnoses. Different coping strategies between diagnosis groups should also be explored, for example, how the internet may be used for social communication.

Conclusion

The Covid-19 public health measures have increased barriers to social connectivity that has increased loneliness among the general public. Pre-existing barriers to social connectivity for people with SMI meant that loneliness was already a substantial problem. Once the pandemic restrictions are removed and barriers to socialising are reduced for the general population then the pre-existing barriers unique to people with SMI will likely remain. There is a risk that loneliness rates may remain higher among those with SMI than the general population and this will exacerbate health inequalities. Further research should follow-up people with SMI as the pandemic restrictions are lifted to understand loneliness trends. Additional study is also needed to understand the barriers to social connectivity for people with SMI, and to understand the best strategies to intervene. Specifically, the internet and digital connectivity should be explored as potential strategies to tackle problems of PSS and loneliness. Theoretical models of loneliness that apply to the general population likely also apply to those with SMI [18], so research should explore the effectiveness of general strategies to reduce loneliness for people with SMI. Intervention strategies may be adapted to tackle the unique barriers experienced by those with SMI. An intervention that is tailored to young adults who live alone may be an effective response to address the main burden of loneliness among people with SMI. Further understanding of loneliness and its relation to mental health among people with SMI is needed to develop this area of research.

20 Sep 2021

PONE-D-21-22036Loneliness among people with severe mental ill health during the COVID-19 pandemic: results from a linked UK population cohort studyPLOS ONE

Dear Dr. Heron,

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ACADEMIC EDITOR: Considering the reviewers comments and my own reading of the paper, I am suggesting a major revision for this paper. Third reviewer who has not submitted full review but saved partial review with following comment.

"The study is timely but lacks methodological and statistical rigor", try to respond to this comment as well.

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Additional Editor Comments (if provided):

Considering the reviewers comments and my own reading of the paper, I am suggesting a major revision for this paper. Third reviewer who has not submitted full review but saved partial review with following comment.

"The study is timely but lacks methodological and statistical rigor", try to respond to this comment as well.

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Reviewer #1: Yes

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available?

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Reviewer #1: Yes

Reviewer #2: No

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Reviewer #1: The topic of research is very interesting and it needs to be published. Nevertheless, I would like to raise the following issues which I considered is good to be taken for the betterment of the paper.

GENERAL

Title: I personally recommend you to take minor revision on your title of the research because it is more comfortable for readers if it can be revised as ‘Loneliness among people with severe mental illness during the COVID-19 pandemic: results from a linked UK population cohort study”

Abstract

Purpose: The title of your research needs to have complete information about what you are going to do. Your title is not sufficient to describe what is mentioned in your purpose of study section. It needs revision; put your exact objective with respect to your topic of interest.

Introduction: interesting

Methods: interesting

Result: Table 2 is out of what you are intended to do; beyond your objective

Discussion: very interesting but too little when compared to what you have reported in the result section and inadequate scientific evidences. Needs revision

References: there are a number of web link citations in the main document; it is good if you use a uniform referencing style.

Reviewer #2: I am very grateful to the Editors that I have the opportunity to revise this manuscript.

Below is my review report:

-The statistic analyzes are well done.

Formal problem:

-IMDD: the meaning of the abbreviation is not explained in the text. If it is Index of Multiple Deprivation, than in Table 1 there is „moderate deprivation” and inTable 2,3 the same category called „medium”. It will be better to check nomenclature and use one name.

-There is a reference form error on page 10: Mishu 2019- I can not find in reference list, and the form is problematic in the text.

Questions or suggestions about method:

-When did you do the reports? I think it can be important, that study sampling was in first “COVID pandemic wave” (2020 spring) or after half/ one year from its beginning. I think mental status could be deterioration after several months of lockdown.

It is interesting finding, regarding the timing of research: “Only a minority of participants reported a worsening to their financial wellbeing or reduction in professional activity during the pandemic.This may be because people with SMI were already disproportionately affected by socioeconomic deprivation and unemployment prior to the pandemic.” Now, among the waves of the COVID pandemic of the past 1,5 years, is this research result still the same or only at the beginning of the pandemic was?

-In this study severe mental ill health is treated as a homogeneous group, it is a question for me that patients with different type of mental illnesses (and different coping ability or pss) can be treat like a homogeneous group.

-I would have also asked in questionare about (online) varieties of social support because just as the general population has replaced personal relationships with this, I think study group as well.

Discussion:

As I read the results and discussion, I felt that the study has the result what I expected at beginning of the introduction part. With the research results, the authors fulfilled the described study goal regarding the explore perceived social support and loneliness and factor associations during the Covid-19 pandemic, but there was no surprising finding at the end. I would have liked to read about what coping methods were, and in more detail what deterioration of loneliness was associated with their patients mental health in lockdown period. Maybe the study questionaire was not enough detailed or targetted, and that is why there is not a breakthrough result.

Conclusion:

“Additional study is also needed to understand the barriers to social connectivity for people with SMI, and to understand the best strategies to intervene.” Correct, and important conclusion. I hope you will continue your study and we will read about the barriers to social connectivity and your strategies to intervene.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: MENGESHA SRAHBZU BIRESAW

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Submitted filename: review report ploseone.docx

Click here for additional data file.

26 Oct 2021

Thank you for reviewing the manuscript and for providing us with feedback to improve the manuscript. We have responded to each of the reviewer comments in the attached document 'Response to Reviewers' alongside the cover letter. I have also pasted the text below.

Dear Plos Editorial team and reviewers,

Thank you for processing the submitted manuscript and for providing us with the opportunity to revise the submitted manuscript. We thank the reviewers for their thoughtful comments which have helped us to revise and improve the manuscript.

We have addressed each of the reviewers’ comments and expanded the manuscript’s discussion section. Please find our detailed responses to each of the comments below in blue text. We hope that the manuscript may now be suitable for publication, but please do not hesitate to contact us if there are matters to address, or if we can provide additional information.

Kind wishes,

Paul Heron

Comments to the Author

Considering the reviewers comments and my own reading of the paper, I am suggesting a major revision for this paper. Third reviewer who has not submitted full review but saved partial review with following comment.

"The study is timely but lacks methodological and statistical rigor", try to respond to this comment as well.

Author response: We have addressed a problem with the study data being publicly available and a problem with the analysis plan in the comments below. The discussion section has been expanded and adds context to the timing of data collection. These points are described in further detail below in response to reviewer comments.

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

Author response: Thank you

________________________________________

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Author response: Thank you

________________________________________

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

Author response: We are not able to share a de-identified data set as we do not have consent from the research participants to do this. We have checked with the GDPR team at the University of York and they have advised us that we cannot upload this data to a public repository without explicit consent from the study participants. Data requests for the full dataset may be sent to the Closing the Gap Network email: ctg-network@york.ac.uk whose steering committee manage our data requests.

________________________________________

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Author response: Thank you

________________________________________

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The topic of research is very interesting and it needs to be published. Nevertheless, I would like to raise the following issues which I considered is good to be taken for the betterment of the paper.

GENERAL

Title: I personally recommend you to take minor revision on your title of the research because it is more comfortable for readers if it can be revised as ‘Loneliness among people with severe mental illness during the COVID-19 pandemic: results from a linked UK population cohort study”

Author response: We have updated the title as recommended

Abstract

Purpose: The title of your research needs to have complete information about what you are going to do. Your title is not sufficient to describe what is mentioned in your purpose of study section. It needs revision; put your exact objective with respect to your topic of interest.

Author response: We have updated the ‘Purpose’ section of the abstract to provide a more complete picture of the manuscript. Taken with the above comment that suggests a minor amendment to the title, we believe that this comment refers to the ‘Purpose’ section of the abstract rather than the manuscript title. We apologise if we have misinterpreted this comment and would be happy to amend the manuscript title further.

Introduction: interesting

Methods: interesting

Result: Table 2 is out of what you are intended to do; beyond your objective

Author response: Thank you for highlighting this. The analysis plan contains an error where it refers to the variable as ‘Social isolation’ rather than ‘Perceived social support’. This can be corroborated by the survey being uploaded prior to analysis which contains a measure of Perceived social support, but no measure of Social isolation (link to survey in analysis plan: https://osf.io/8qwhd/#!). We have added information to the ‘Analysis’ section of the manuscript to clarify this.

Discussion: very interesting but too little when compared to what you have reported in the result section and inadequate scientific evidences. Needs revision

Author response: We have expanded the discussion section. In particular, we discuss two points, mentioned in the below comments; the internet and digital connectivity for social contact, and adding context to when the data was collected in relation to pandemic restrictions.

References: there are a number of web link citations in the main document; it is good if you use a uniform referencing style.

Author response: We have updated the in-text weblinks to maintain consistency

Reviewer #2: I am very grateful to the Editors that I have the opportunity to revise this manuscript.

Below is my review report:

-The statistic analyzes are well done.

Formal problem:

-IMDD: the meaning of the abbreviation is not explained in the text. If it is Index of Multiple Deprivation, than in Table 1 there is „moderate deprivation” and inTable 2,3 the same category called „medium”. It will be better to check nomenclature and use one name.

Author response: We have updated the text to explain the abbreviation, and to refer to it as Index of Multiple Deprivation (IMD), rather than Index of Multiple Deprivation Decile (IMDD) which was incorrect. The text also now consistently refers to the middle category as ‘moderate’ deprivation.

-There is a reference form error on page 10: Mishu 2019- I can not find in reference list, and the form is problematic in the text.

Author response: We have updated the reference list and article body to add the Mishu 2019 reference. Other references have also been re-numbered to allow this.

Questions or suggestions about method:

-When did you do the reports? I think it can be important, that study sampling was in first “COVID pandemic wave” (2020 spring) or after half/ one year from its beginning. I think mental status could be deterioration after several months of lockdown.

It is interesting finding, regarding the timing of research: “Only a minority of participants reported a worsening to their financial wellbeing or reduction in professional activity during the pandemic.This may be because people with SMI were already disproportionately affected by socioeconomic deprivation and unemployment prior to the pandemic.” Now, among the waves of the COVID pandemic of the past 1,5 years, is this research result still the same or only at the beginning of the pandemic was?

Author response: Thank you for this. We have added detail to the discussion to add context to these findings and discuss how long-term effects of restrictions may have influenced the findings.

-In this study severe mental ill health is treated as a homogeneous group, it is a question for me that patients with different type of mental illnesses (and different coping ability or pss) can be treat like a homogeneous group.

Author response: We were also interested to explore differences between diagnoses but did not want to conduct too many post-hoc analyses. We have now added detail to the ‘Limitations’ section to discuss this.

-I would have also asked in questionare about (online) varieties of social support because just as the general population has replaced personal relationships with this, I think study group as well.

Author response: Thank you, we have now added detail to the discussion about the role of internet and digital devices in social communication during the pandemic among people with SMI. Digital connectivity and internet use was explored as part of the OWLS study in a separate article, so we have referred readers to these articles for further information.

Discussion:

As I read the results and discussion, I felt that the study has the result what I expected at beginning of the introduction part. With the research results, the authors fulfilled the described study goal regarding the explore perceived social support and loneliness and factor associations during the Covid-19 pandemic, but there was no surprising finding at the end. I would have liked to read about what coping methods were, and in more detail what deterioration of loneliness was associated with their patients mental health in lockdown period. Maybe the study questionaire was not enough detailed or targetted, and that is why there is not a breakthrough result.

Author response: Thank you. Due to the continually changing nature of the pandemic, and how concerning we found these findings to be, we felt it was important to publish these results early. We hope they will generate interest and discussion around the topic. In time, we plan to publish the OWLS study’s follow-up data to explore long-term trends in loneliness and social support, and to explore these topics with qualitative methods.

Conclusion:

“Additional study is also needed to understand the barriers to social connectivity for people with SMI, and to understand the best strategies to intervene.” Correct, and important conclusion. I hope you will continue your study and we will read about the barriers to social connectivity and your strategies to intervene.

Author response: Thank you.

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

16 Nov 2021

PONE-D-21-22036R1Loneliness among people with severe mental illness during the COVID-19 pandemic: results from a linked UK population cohort studyPLOS ONE

Dear Dr. Heron,

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.

ACADEMIC EDITOR: Considering the reviewers suggestion, I am going with a decision of minor revision.

Please submit your revised manuscript by Dec 31 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're 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.

Please include the following items when submitting your revised manuscript:If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

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We look forward to receiving your revised manuscript.

Kind regards,

Srinivas Goli, Ph.D.

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Additional Editor Comments:

Considering the reviewers suggestion, I am going with a decision of minor revision.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: THANK YOU very much for addressing my concerns for the betterment of the paper. in its current status it has became an interesting paper.

Reviewer #2: Dear Author!

Thank you for your revised manuscript and answers for my questions.

Your manuscript is still timely, but need minor revision.

My review report:

Technical problem:

Reference 33: There are 9 authors mentioned, and as I know you should write max. 6 then abbreviation et al.- Please look after it, and correct.

1. Abstract: Purpose: Aim/ goal/ purpose - the term- should be use in drafting this part of manuscript - please revise (content is ok)

2. Introduction, result part do not need further revision- in my opinion.

3. Methods: Data collection timing should be here mentioned firstly.

4. Discussion

Discussion needs revision. The main message of your study and the results should be in focus, and should be detailed here. Now the new paragraphs seem to be too detailed- as I see the whole discussion, and the results. Conditions of data collection and its timing need to be shorten here. Use of internet by SMI patient is very interesting, and it is good to read about it, but not involved in this study- so it is an additional information, need compress too.

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: MENGESHA SRAHBZU BIRESAW

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

20 Dec 2021

Dear PLOS ONE Editorial team and Reviewers,

On behalf of the authors, thank you to the editors and reviewers. We appreciate your feedback to refine and improve the article. We have updated the article in line with the recommendations. Please see the relevant 'Author response' to each point below.

We hope that the article may be ready for acceptance. Please do not hesitate to contact me if you would like to discuss the manuscript further.

Kind wishes,

Paul

Feedback from PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Author response: The reference list has been updated to correct errors.

Additional Editor Comments:

Considering the reviewers suggestion, I am going with a decision of minor revision.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

________________________________________

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

________________________________________

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

________________________________________

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

________________________________________

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

________________________________________

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: THANK YOU very much for addressing my concerns for the betterment of the paper. in its current status it has became an interesting paper.

Reviewer #2: Dear Author!

Thank you for your revised manuscript and answers for my questions.

Your manuscript is still timely, but need minor revision.

My review report:

Technical problem:

Reference 33: There are 9 authors mentioned, and as I know you should write max. 6 then abbreviation et al.- Please look after it, and correct.

Author response: This has been corrected.

1. Abstract: Purpose: Aim/ goal/ purpose - the term- should be use in drafting this part of manuscript - please revise (content is ok)

Author response: The terms in this section have been updated.

2. Introduction, result part do not need further revision- in my opinion.

Author response: Thank you.

3. Methods: Data collection timing should be here mentioned firstly.

Author response: The methods have now been updated with the recruitment and data collection timing.

4. Discussion

Discussion needs revision. The main message of your study and the results should be in focus, and should be detailed here. Now the new paragraphs seem to be too detailed- as I see the whole discussion, and the results. Conditions of data collection and its timing need to be shorten here. Use of internet by SMI patient is very interesting, and it is good to read about it, but not involved in this study- so it is an additional information, need compress too.

Author response: The discussion section has had some detail removed to make it more succinct. This will also mean that the focus of the discussion is placed more on the main findings.

Submitted filename: Response to reviewers 20_12_21.docx

Click here for additional data file.

23 Dec 2021

Loneliness among people with severe mental illness during the COVID-19 pandemic: results from a linked UK population cohort study

PONE-D-21-22036R2

Dear Dr. Heron,

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

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. 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 help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- 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.

Kind regards,

Srinivas Goli, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Revisions are satisfactory, thus I am recommending this article for publication in PLOS One. However, before publishing please ask authors to format the Tables and the paper in line with PLOS One guidelines. They are not looking good in its present form.

Reviewers' comments:

4 Jan 2022

PONE-D-21-22036R2

Loneliness among people with severe mental illness during the COVID-19 pandemic: results from a linked UK population cohort study

Dear Dr. Heron:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. 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.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Srinivas Goli

Academic Editor

PLOS ONE