Psychometric approach to evaluate periodontal disease using Revised Illness Perception Questionnaire.

INTRODUCTION: Illness perception is the cognitive representation of an illness, which determines how a person responds to it. The Revised Illness Perception Questionnaire (IPQ-R) assesses seven components of illness representation in various chronic diseases, but queries prevail about its factor structure. The study assesses the components of illness representation in patients with chronic periodontitis.
MATERIALS AND METHODS: A total of 625 voluntary, consecutive dental patients with a clinical diagnosis of periodontitis were recruited into the study. The Hindi version of IPQ-R was used, consisting of three parts-identity scale, structured scale, and perceived causes of the patient's ailment.
RESULTS: Of the 625 participants, 44.0% reported cyclical disease pattern, 30.4% said their disease was a mystery. Only 1.6% predicted it to remain throughout their life. A total of 44.0% of participants reported the disease to impact their day-to-day life severely. A significant difference was observed between males and females across seven components of IPQ-R. While 21.6% of participants attributed stress to be a major cause for their diseased state, 20.8% reported workload to be a major cause, but 42.4% attributed poor medical care in the past to be a major cause for their state.
CONCLUSIONS: A sensible approach to treating a disease is to measure the patient's illness perception and target specific interventions accordingly. It would be cost-effective and break misconceptions about diseases in patients, ultimately providing them with better overall health and satisfaction. Copyright:

INTRODUCTION

Periodontitis is a chronic disease of multifactorial origin characterized by clinical loss of periodontal attachment in response to host-mediated microbe-driven inflammation.[1] According to the World Health Organization, periodontal health should not only be defined as a state free from inflammatory periodontal disease but also mental and physical well-being as the course of any chronic disease is largely affected by the mental well-being of a person.[2]

Illness perception is the cognitive representation of an illness, which determines how a person responds to it and is accurately described by the common sense model (CSM) of self-regulation suggested by Leventhal et al.[3] Experience of diseases, lifestyle, somatic sensations, observations and discussions, mass media, and environmental cues activate the memory structure of an individual, which governs future behavior.[34] In the CSM model, users add salient features to either a specific patient group or specific health threat based on ideas about the nature of illness and its associated symptoms and the targets for change (identity); beliefs about why they developed their illness (causes); perceptions regarding the propensity of the illness to being cured, prevented or treated (cure/control); beliefs about the seriousness of the disease and impact upon everyday life (consequences); beliefs about how long an illness persists, including symptoms and recovery (timeline-acute/chronic); feelings that arise as a result of the illness, such as anxiety or depression following the diagnosis of a condition (emotional representations); the degree to which individuals feel they understand a specific illness (illness coherence); and perceptions about variability in symptoms (timeline-cyclical).[567]

In an attempt to understand the nature of coping behavior and psychology behind the development of interventions that facilitate self-management in chronic illness, a psychometrically sound Illness-Perception Questionnaire (IPQ) was developed by Weinman et al.[8] which assess the components of illness representation based on CSM. The Revised IPQ (IPQ-R) further included two more components to include an evaluation of an individual's emotional response to their illness (emotional representation) and the sense of comprehensively understanding one's own illness (illness coherence). Moreover, the timeline scale was separated into acute-chronic and cyclical subscales, and the control scale was divided into personal control and treatment control components. The reliability and factor structure of IPQ-R has been established in a variety of chronic diseases such as end-stage renal disease,[5] hypertension,[9] diabetes,[10] myocardial infarction,[11] and cancer.[12]

Although a large number of investigations used the IPQ-R, there is no agreement about its factor structure.[5] In some studies, the factor structure of the IPQ-R has been supported in specific chronic illness groups, the composition of the scale varied among the studies.[91011121314] Studies related to illness perception are limited in India, and this calls for further analysis to determine whether perception varies in different geographical regions and among people with cultural diversity. With this background, the present study aims to assess the properties of IPQ-R in periodontitis.

MATERIALS AND METHODS

Study participants

The sample comprised 625 voluntary, consecutive dental patients with a clinical diagnosis of periodontitis. The sample size was determined using the estimated values from literature using the formula, Total sample size = N = ([Zα+Zβ]/C) 2 + 3, keeping an α error of 5% and β error of 20%, thus giving power of study of 80%. Informed consent was obtained from all participants and parents in participants under 18 years of age. The study data were collected between February and November 2019. The Institutional Ethical Committee approved the protocol study and procedures.

Inclusion criteria

Systemically healthy patients diagnosed with generalised chronic periodontitis having interdental clinical attachment level (CAL) at ≥2 nonadjacent teeth or buccal/oral CAL ≥3 mm with probing depth >3 mm at ≥ two teeth. Periodontitis staging was then defined according to interdental CAL at the site of the greatest loss of 1 mm–2 mm, 3 mm–4 mm, and ≥5 mm as mild (Stage 1), moderate (Stage 2), and severe (Stage 3–Stage 4), respectively. Patients should be cooperative with the presence of more than 20 natural teeth.

Exclusion criteria

Patient with any systemic disease or medication that could alter periodontal status, under the influence or dependent on drugs or alcohol, pregnant or lactating mother. Patients with a psychiatric, developmental, and degenerative brain disorder could affect emotional or cognitive functions as reasoning and judgment are diminished significantly.

Revised Illness Perception Questionnaire

The Hindi version of IPQ-R was used, which mainly consisted of three parts. The Questionnaire consisted of closed-ended questions. The first part was the identity scale consisted of eleven common oral illness symptoms. Participants were asked to recognize the signs and symptoms they experienced when they suffered, using a dichotomous variable response (yes/no). The second part was a structured scale assessing the seven components of illness perceptions. Finally, the third part probed the causes of the patient's ailment. In this step, common reasons included factors such as “psychological,” “hereditary,” “lifestyle,” “immunity,” and “accidental/chance.” Participants were then asked to mark the most critical causes from each of the four categories that influenced their disease development. The Questionnaire was filled by the participants (self) who had completed at least primary education or had higher education. For illiterate patients, the operator filled the Questionnaire after explaining the entire questionnaire to the patient.

Validity of Revised Illness Perception Questionnaire

The Hindi version of the IPQ-R was tested for validity before the initiation of the study. A pilot study was designed with 15 participants that were homogenous to socio-demographic variables. Internal validity was checked using Cronbach's alpha.

Statistical analysis

Frequencies and percentages were calculated with the entire sample to determine the distribution of categorical variables. Mean and standard deviation (SD) for continuous data were calculated. An independent Chi-squared test analysis was also performed to examine the sample variation in males and females. For all the statistical tests, P < 0.05 was considered to be statistically significant. Data were subjected to statistical analysis using the Statistical Package for social sciences (IBM SPSS Statistics for Windows, version 21.0. IBM Corp., Armonk, New York, USA).

RESULTS

Table 1 represents the sociodemographic characteristics of the participants. The age of participants ranged from 13 to 69 years (Mean = 32.94, SD = 12.18 years). The majority of the individuals were males (60.00%). They belonged to a low socioeconomic status (73.6%). About 76% of participants were residents of Jaipur. Regarding education, 24.8%, 44.8%, and 26.4% had completed primary, secondary, and higher education, respectively. Hence, the literacy rate of the population studied was adequate to comprehend and understand the questions asked. There was an overall excellent internal consistency of the questions with Cronbach's alpha values of 0.941(α ≥0.9 – excellent internal consistency).

Table 1

Sociodemographic characteristics of the study participants stratified by gender

Characteristics	Total (n=625)	Males (n=375)	Females (n=250)	P*
Age	32.94±12.18	33.78±13.87	30.23±14.23	0.57
Socio economic status
Low	73.6	72.0	76.0	0.66
Middle	20.0	20.0	20.0
High	6.4	8.0	4.0
Residence
Jaipur	76.0	44.0	80.0	0.39
Others	24.0	26.6	20.0
Education
Illiterate	4.0	0.8	8.0	<0.05*
Primary	24.8	8.8	40.0
Secondary	44.8	56.0	28.0
Higher	26.4	28.0	24.0
Marital status
Single	30.4	38.6	18.0	0.03*
Married	62.4	53.3	76.0
Divorced	7.2	8.0	6.0

n: number, P: Probability value, *P < 0.05 is considered to be statistically significant

In the identity scale of IPQ-R, 69.6% of participants responded to have receding gums, loose teeth. About 30.4% of participants responded to have had alternation in the fitting of teeth during a bite. Table 2 outlines the responses to various components of illness representation. A significant difference (P < 0.05) was observed between males and females across statements of the cyclical pattern of disease and illness coherence. Of the 625 participants, 44.0% reported that their dental problems change day to day, 30.4% reported their disease being a complete mystery to them, with the proportion mentioning such being higher in females. About 50% of participants assumed their disease would resolve quickly, whereas 1.6% predicted it to remain throughout their life. About 70% reported that the disease progression was controlled through self-awareness and treatment. However, only 7.2% of participants documented financial loss due to the same. In terms of consequences, 44.0% of participants reported the disease to have some serious impact on their day-to-day life and affect how other people see them. Also, 48.80% of participants reported getting sad about thinking about their disease. In the illness coherence component, the majority (83.2%) reported that they understand their disease completely, which was significantly higher in males.

Table 2

Responses to the components of illness representation of Revised Illness Perception Questionnaire stratified by gender

Components	Statements	Total (n=625)	Males (n=375)	Females (n=250)	P*
Cyclic	Symptoms/side effects of dental problem changes day to day	44.0	52.0	32.0	<0.05*
	Symptoms/side effects of dental problem comes and goes in cycles	17.6	26.6	4.0
	Dental problem is complete mystery	30.4	17.3	50.0
	Cycles in which dental problem gets better or worse	8.0	4.0	14.0
Acute/chronic	Dental problem resolves quickly	52.0	53.3	50.0	0.43
	Dental problem lasts for a short time	9.6	9.3	10.0
	Dental problem improves with time	29.6	33.3	24.0
	Dental problem lasts for long time	3.2	1.3	6.0
	Dental problem likely to be permanent	4.0	2.6	6.0
	Dental problem will be throughout life	1.6	0.0	4.0
Self-control	Self-control the disease	76.0	80.0	70.0	0.18
	Have the power to deal with disease	18.4	17.3	20.0
	Nothing will affect dental problem	5.6	2.6	10.0
Treatment control	Treatment will be effective in resolving dental problem	72.0	73.3	70.0	0.34
	Treatment will reduce dental problem	24.8	25.3	24.0
	There is nothing which can help dental problem	3.2	1.3	6.0
Consequence	Dental problem is a serious condition	22.4	26.6	16.0	0.36
	Dental problem has major impact in life	44.0	40.0	50.0
	Dental problem have serious financial consequences	7.2	9.3	4.0
	Dental problem strongly affects the way others see me	19.2	18.6	20.0
	Dental problem causes difficulties for those close to me	7.2	5.3	10.0
Emotional	I get sad thinking about dental problems	45.8	45.3	54.0	0.11
	I get angry thinking about dental problems	8.0	10.6	4.0
	I feel afraid thinking about dental problems	21.6	17.3	28.0
	Dental problems do not worry me	21.6	26.6	14.0
Illness coherence	I understand dental problems	83.2	93.3	68.0	<0.05*
	I don’t understand dental problems	7.2	2.6	14.0
	Dental problem is a mystery to me	6.4	2.6	12.0
	Dental problem does not make any sense	3.2	1.3	6.0

n: number, P: Probability value, *P < 0.05 is considered to be statistically significant

About 21.6% of participants attributed stress to be a major cause for their diseased state, while 20.8% reported workload to be a major cause. In terms of causal item risk factors, 42.4% attributed poor medical care in the past to be a major cause for their diseased state. Table 3 depicts the remaining proportions of perceived causes.

Table 3

Perceived causes of ailment stratified by gender

	Total (n=625)	Males (n=375)	Females (n=250)	P*
Psychological
Stress or worry	21.6	24.0	18.0	0.06
My mental attitude	16.0	13.3	20.0
Family problems or worries	19.2	13.3	28.0
Overwork	20.8	26.6	12.0
My emotional status	14.4	10.6	20.0
My personality	8.0	12.0	2.0
Risk factors
Hereditary	8.0	8.0	8.0	0.76
Diet or eating habits	16.8	12.0	24.0
Poor medical care in past	42.4	42.6	42.0
Aging	20.0	18.6	22.0
Smoking	4.8	5.3	4.0
Alcohol	8.0	13.3	0.0
Immunity
Virus or germ	93.6	92.0	96.0	0.37
Pollution in environment	6.4	8.0	4.0
Accident or chance
Chance or bad luck	81.6	80.0	84.0	0.57
Accident or injury	18.4	20.0	16.0

n: number, *P: Probability value; *P < 0.05

DISCUSSION

The definition of periodontal health includes characteristics related to a painless functional dentition, stability of the tissues that support the teeth, and psychosocial well-being of the individual.[13] In the present study, the patient's perspective describes the periodontal disease as an acute, cyclic self-limiting disease that can be cured by treatment but has an emotional impact on their life. Most subjects were unaware that they had developed a chronic disease until modified by systemic, environmental, and behavioral factors. Gingival bleeding during brushing, flossing, and other oral hygiene procedures or eating remains the first self-reported sign of disease in the majority of participants.[14]

The rate of progression of chronic periodontitis is not equal throughout the mouth. Some areas may progress rapidly, while the other sites may remain static for a more prolonged period with maximum progression in interdental areas. The cyclic nature of periodontitis has been well established. Goodson et al. well explained that the diseased sites undergo periods of exacerbation that show bleeding on probing with an increased amount of gingival exudates followed by periods of quiescence or inactivity.[15] The self-limiting nature of periodontitis as perceived by subjects in our study may also point to the period of inactivity in pathogenesis.

Progressive attachment loss and bone loss together with marginal tissue recession may lead to patients noticing black triangles between teeth or hypersensitivity to a hot and cold stimulus or food items. In advanced cases, tooth mobility with tooth loss, areas of food impaction, itching, and tenderness may also be reported.[16] All these factors increase anxiety and fear toward disease in patients, thus emotionally affecting them. A strong link has already been established between stress and periodontal diseases by Genco et al.[1718] The present study also reverberated the findings with stress as the most common causal factor for their diseased state.

Interestingly, 30.4% of the participants considered the disease mysterious, with females reporting it in a significantly higher proportion. It could be attributed to illiteracy being higher in the case of females. However, certain studies have shown that myths, fallacies, and misconceptions greatly prevail even among the educated group of society.[19202122] These myths about dental diseases strongly affect a person's perception of his disease, affecting his mental, social, and physical well-being. The fact that less but 3.2% of patients perceived their disease as being incurable by treatment, having financial constraints (7.2%), getting emotionally disturbed (48.6%), and perception of society toward them (7.2%) are major concerns that should not be ignored. All these reflect the fact that there is a lack of awareness among the general public regarding the nature and treatment of gingivitis and periodontitis. The conventional norms and taboos still prevail among the general public of India. A myth like scaling loosens the teeth and increases the gaps between them still exist among individuals.[23] Hoving et al. deduced that unhelpful and maladaptive illness perception could lead to decreased work participation and economic and social deprivation.[4] Such a group of people should be the primary focus as they feel afraid. The periodontal bleeding might be an explanation as to why such feeling exists. Blood could negatively impact and may represent that one has lost control of one's own life.[24]

These myths and taboos regarding periodontal disease need to be changed. Periodontal therapy allows periodontists to interact and assess the mental status and rule out negative perceptions of a patient toward periodontitis, which, if left unattended, could lead to an indifferent course. The present questionnaire could serve as a medium to rule out such negative perceptions and help formulate customized motivation and counseling sessions as the success of any periodontal therapy depend on how well a patient is motivated and educated about his disease. The use of motivational intervenes as an adjunct to periodontal treatment has been shown to have a positive influence on clinical parameters and psychological factors related to oral hygiene.[25]

In the present study, validation of the Hindi version of IPQ-R via Cronbach's alpha showed an excellent internal consistency (Cronbach's alpha – 0.941). The current study results are in line with the study by Mafla et al., who validated the Spanish version of IPQ-R and concluded that IPQ-R had adequate reliability and construct factorial validity in screening illness perception in patients with periodontal disease.[24] To our best knowledge, the present study is the first of its kind to record responses to components of illness representation using IPQ-R in patients with periodontal disease.

In the light of these results, the relevance of doing this study is that we believe using such instruments for future cross-cultural comparative studies in patients with periodontal disease can lead to additional data analysis for further validation and generalizability of IPQ-R. Such studies persuade further to conduct counseling sessions to analyze patients’ behavior and provide them with better education and motivation leading to social, mental, and physical rehabilitation. Even though there is a short version of this questionnaire developed by Moss-Morris et al.[26] or by Broadbent et al.,[27] it was only based on some medical conditions, and further research is necessary for a better understanding of their take on disease.

However, this study is not without limitations. Though the sample size was adequate, it adopted a nonprobability consecutive sampling technique. The study population comprised mainly of people from Jaipur, Rajasthan, which affects the generalizability of the findings. Moreover, data were self-reported, and presentation bias might exist despite the anonymous questionnaires. We could have used the Likert scale to measure participants’ responses to obtain the severity of each component affecting their perception instead of choosing only one option per component.

CONCLUSIONS

In the modern era of health care, a sensible approach to treating a disease is to measure patients’ illness perception toward the most common chronic diseases and target specific interventions accordingly. It would be a cost-effective option compared to the standard norm of present-day health care, which advocates the same treatment to everyone. The relevance of discussing patients’ perception creates a feeling of support and satisfaction in them; however, most health care professionals are still unaware of the same. Such studies could break misconceptions about the disease in patients and educate them, ultimately providing them with better overall health and satisfaction.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.