بازنمودهای بیماری در میان بیماران مبتلا به دیابت نوع 2 و شرکای خود: روابط با رفتارهای خودمدیریتی

Objective There is accumulating evidence to indicate that the illness representations of significant others are important for understanding patients' responses to chronic disease. The aims of the present study were to (a) assess the illness representations of patients with type 2 diabetes and their partners, (b) determine the extent of agreement between patient and partner representations, and (c) examine whether partners' representations mediate the relationships between patients' representations and their prospective self-management behaviors. Methods Patients' and partners' representations of diabetes were assessed with the Revised Illness Perception Questionnaire [Moss-Morris R, Weinman J, Petrie K, Horne R, Cameron LD, Buick, D. The revised illness perception questionnaire (IPQ-R). Psychol Health 2002;17:116] at baseline (n=164). Self-management behaviors were assessed 12 months later with self-report measures of physical activity, medication, and a food frequency questionnaire. Results Patients scored lower on the illness coherence dimension, indicating that they reported a poorer understanding of the condition (t=−2.66, df=163, P=.009) relative to their partners. Patients demonstrated higher scores for personal control than their partners (t=2.01, df=163, P=.046). Mediational analyses indicated that partners' perceived timeline of diabetes partially mediated the relationship between patients' representations and their self-management behaviors including physical activity and dietary intake. In addition, partners' personal control representations partially mediated the relationship between patients' representations and physical activity. Conclusion It was demonstrated that patient–partner dyads generally share similar representations of type 2 diabetes and perceived control over the condition. Furthermore, there was evidence that partners' representations partially mediated the relationships between patients' representations and their prospective self-management behaviors.

The social support literature indicates that individuals in a patient's support network can influence their behavioral responses to illness. Within diabetes, this literature has identified both beneficial and adverse effects. The receipt of social support, for example, has been shown to favor better self-management of diabetes [1], [2], [3] and [4]. However, evidence suggesting that family interactions may hinder engagement in self-care behaviors such as physical activity and diet also exists [5]. The question remains, therefore, by what mechanisms do significant others exert their influence? It is proposed that the perceptions of illness held by significant others may be one of the mechanisms through which significant others influence patient outcomes. The present study was designed to examine this issue in patients with type 2 diabetes and their partners, using the theoretical framework of the Self-Regulatory Model (SRM) [6]. The SRM posits that the patient is an active participant in the health care process [6]. It is also argued that an individual experiencing illness may perceive a range of problems that are pertinent only to that individual, while others experiencing the same condition have their own unique experiences. In order to make sense of and respond to these problems, patients create their own “models” or representations of their illness that then influence their coping and care-seeking behavior [7]. The process is regarded as self-regulatory because the three components of the model, that is, interpretation, coping, and appraisal, have been shown to interrelate in order to maintain the status quo. Therefore, if an individual's normal state of health is disrupted by illness or the threat of illness, the model proposes that he or she is motivated to regain the balance [8]. It is postulated that these representations emerge as soon as patients experience symptoms or are given a disease label and may change with disease progression, the emergence of further symptoms, and responses to medical intervention. Furthermore, it is argued that illness representations not only give personal meaning to patients' symptoms and experience of illness but also act as a framework for guiding and evaluating coping efforts that are evoked to deal with the illness. Furthermore, the self-regulation process is considered to be dynamic, as feedback from appraisals of coping efforts influence cognitive representations, emotional responses, and future coping efforts [7]. It is proposed that these illness representations are formulated around five “core” dimensions regarding the cause, control, timeline (course), consequences, and identity (perceived symptoms) of the condition. The cause dimension acknowledges that patients may have their own ideas regarding the possible causes of the illness that may or may not conform to medical opinion. Perceived consequences relate to the extent that the patient is aware of the potential seriousness or severity of the disease. Representations regarding timeline refer to patients' understanding of the duration of the disease and likely timeline of future progression of their disease. The control dimension measures the extent of patients' perceived personal control of their illness and the extent of perceived treatment control. Finally, illness identity captures the symptoms that a patient experiences in relation to the disease. These illness representations, therefore, provide a coherent and empirically based framework for investigating adaptation to chronic disease. Indeed, there is accumulating evidence that illness representations are associated with self-management behaviors and treatment outcomes across a range of chronic diseases [9], [10], [11], [12], [13], [14], [15], [16] and [17]. In recent years, there has been a growing interest in extending the application of the SRM to explore not only the representations of patients but also the representations of significant others. To date, much of this work has focused on patients' psychological adaptation to chronic disease. In addition, this work has focused not only on the relationship between the representations of patients and significant others but also on how such representations may influence patient outcomes. Differences between the representations of significant others and patients have been shown to play a role in influencing psychological adaptation to chronic fatigue syndrome (CFS) and Addison's disease (AD) [18]. In both cases, patient and partner dyads were found to hold similar views with regard to the dimensions of illness identity and cause but disagreed on the timeline, control/cure, and consequences of the illness. The partners of patients with CFS and AD held more pessimistic views with regard to the timeline of the illness than the patients themselves. In addition, the partners of patients with CFS were inclined to “minimize” the seriousness of the illness regarding the consequences and control of the illness, while the partners of patients with AD had a tendency to “maximize” or exaggerate the seriousness of the disease. In a more recent study, divergent representations between patients and partners about psoriasis were shown to be associated with increased psychological distress [19]. Differences in patients' and partners' representations about the chronicity and emotional impact of psoriasis accounted for 23% of the variance in depression among partners. Adaptation following myocardial infarction (MI) has also been found to be dependent on patients and partners sharing similar representations of the condition [20]. Patients' recovery from MI, measured by assessments of vitality and psychosocial adjustment, was more favorable in dyads with similar “positive” identity and consequence representations compared with dyads with similar “negative” or “conflicting” representations. In addition, patients from dyads with similar representations about the identity and consequences of MI reported lower levels of disability, better psychological adjustment, and less impact on social activities. Finally, to date, there has only been one study that has examined how partners' representations influence self-management behaviors. In this study, Weinman et al. [11] demonstrated that spouse representations of MI being caused by poor health habits were the most important factor in patients' levels of exercise at 6 months. Taken together, these studies indicate that the representations of significant others play an important role in adaptation to chronic disease. Furthermore, it is likely that they may be important in understanding patients' behavioral responses to chronic “lifestyle” conditions such as type 2 diabetes. Type 2 diabetes (non-insulin dependent) presents as a spectrum of metabolic abnormalities characterized by prominent insulin resistance and relative insulin deficiency. It accounts for about 90% of all cases of diabetes, tending to emerge in mid- to late adulthood. The major risk factors for diabetes include a family history of diabetes, obesity [body mass index (BMI) ≥27 kg/m2], age (≥45 years), hypertension, and high cholesterol levels. There is a progressive increase in the worldwide prevalence of type 2 diabetes. This increase is primarily the result of lifestyle changes and, in particular, the steady rise in the prevalence of obesity [21]. The longer the duration of diabetes is, the greater is the likelihood of developing symptoms and signs of degenerative complications. The consequences of poor management of type 2 diabetes can be severe. Complications related to diabetes include blindness, amputations, and diseases of the kidneys, the heart, and the central nervous system [22]. The treatment of diabetes and its complications also constitutes a huge financial burden, accounting for around 5% of the UK National Health Service budget [23]. Apart from being a serious chronic illness and social problem, patients with type 2 diabetes have the principal responsibility for the management of their illness. In particular, the daily management of diabetes involves eating regular healthy meals, taking physical exercise, self-testing blood glucose levels, and, for many patients, taking medicine. The goal of this combination of tasks is to maintain glucose levels within a target range—by achieving tight blood glucose control, the rate of complications decreases [24]. Self-management involves not only completing such activities but also considering the interrelationships among these tasks and implementing appropriate changes in the daily plan when necessary. However, rates of nonadherence with these behaviors are high, ranging from 30% to 75% [25], and often result in poor disease outcomes [26]. Indeed, it has been suggested that the risk of diabetic complications could be reduced by up to one third, if such “avoidable” factors could be removed [26]. Therefore, a major concern in the management of type 2 diabetes is how to encourage adherence with prescribed regimens. To date, no study has been conducted to explore the impact of representations of significant others on the self-management behaviors of patients with type 2 diabetes. There are three main reasons why such an inquiry would appear appropriate in this patient group. First, as rates of engagement with diabetes self-management behaviors are low [25], it is recognized as being particularly problematic [27]. For instance, following dietary advice and taking physical activity are noted as being the most difficult aspects of the treatment regimen for patients to successfully engage with [12]. Second, the principal responsibility for the management of the disease lies with the patient. However, unlike many other conditions, many of the self-management behaviors required of the patients are likely to affect both the patients and their social milieu (e.g., dietary change, uptake of exercise). Thus, one might expect that the representations of individuals who make up one's social milieu, such as the patient's spouse, may be of particular importance. Third, it is likely that patients require considerable support and, as is evident from work with other chronic diseases, the support provided by spouses is often the most influential form of support [28]. Thus, it is proposed that spouses may be influential in patients' management of type 2 diabetes. The present study, therefore, sought to (a) assess the illness representations of patients with type 2 diabetes and their partners, (b) examine the extent of agreement between patients' and partners' representations, and (c) examine whether partners' representations mediate the relationships between patients' representations and their prospective self-management behaviors.

The mean age of the patients was 67 years (range=32–86, S.D.=10.5). The mean duration of cohabitation was 35.5 years (median=38, range=2–64 years), indicating that most participants were in long-standing relationships. Only 5% of participants were from non-European ethnic groups. The mean BMI for patients was 31.5 (range=16–48, S.D.=5.53), with 82% scoring above the cutoff for being overweight (>25). Only 37 patients reported using insulin to control their diabetes (see Table 1). Table 1. Demographic data for the sample population (n=164) Demographics Value Age in years, mean (range) Patients 67 (32–86) Partners 67 (33–87) Gender (n) Male 97 Female 67 Ethnicity (% White European) Patients 95 Partners 97 Disease duration Mean (S.D.) 8.8 (7.07) years Range 6 months to 38 years Diabetes medication, n (%) Oral 107 (80) Insulin 37 (28) BMI, mean (S.D.) 31.5 (5.53) Number of years married/living together Mean (S.D.) 35.6 (14.7) Range 2–64 Occupation (%) Patients Retired 54 Professional 10 Semiskilled manual 32 Unemployed 4 Partners Retired 47 Professional 5 Semiskilled manual 38 Unemployed 10 Age when patients/partners left school (%) Patients 14 years 28 15 years 32 16 years 25 Other age 15 Partners 14 years 24 15 years 37 16 years 24 Other age 15 Comorbidity in the last 12 months (%) Arthritis 31 Asthma 11 Nervous disorders 11 Angina 12 MI 6 Hypertension 43 Other heart trouble 9 Stroke 6 Cancer 6 Table options Diabetes representations Examination of the mean scores shown in Table 2 revealed that patients and partners held strong beliefs in a chronic timeline, such that it was believed that diabetes was a long-term illness. Patients and partners also believed the consequences of diabetes to be serious while perceiving that they had a high degree of illness coherence or understanding of the condition. In addition, dyads' scores for treatment control demonstrated strong beliefs in the efficacy of treatments for diabetes. Table 2. Descriptive statistics and paired t-test results (two tailed) for illness representation scales (n=164 patient–partner dyads) Representation Cronbach's α Mean (S.D.) t Patient Partner Patient Partner Timeline—acute .63 .73 23.2 (4.81) 23.7 (4.32) −.1.04 Timeline—cyclical .60 .66 11.1 (2.79) 10.8 (2.84) 1.14 Consequences .61 .58 17.2 (3.83) 17.1 (3.61) −0.29 Personal control .61 .54 23.4 (3.81) 23.1 (4.46) 2.00⁎ Treatment control .68 .63 22.9 (4.67) 23.5 (3.49) 1.58 Illness coherence .85 .81 17.5 (4.67) 18.4 (4.35) −0.265⁎⁎ Emotional representations .80 .81 12.1 (3.61) 12.6 (3.74) −1.09 Cause—own behavior .71 .69 14.4 (4.01) 14.2 (4.56) 0.916 Cause—external .67 .68 12.7 (3.57) 12.6 (3.57) 0.548 Cause—hereditary N/A N/A 3.2 (1.27) 3.2 (1.25) 0.572 Identity—high blood glucose N/A N/A 3.16 (2.23) 3.25 (2.31) −0.378 Identity—low blood glucose N/A N/A 3.20 (2.33) 3.41 (2.47) −0.883 ⁎ P<.05. ⁎⁎ P<.01. Table options Self-management behaviors A total of 107 patients (65%) reported taking oral medication to control their diabetes. Scores on the MARS ranged from 6 to 30, although most patients reported high levels of medication adherence (mean=28.3, S.D.=5.0). Scores for the Baecke physical activity questionnaire (n=134) ranged from 2 to 16, with a mean of 7.6 (S.D.=3.0). The data demonstrated that 72% of patients engaged in low-intensity exercise. The ratio of patients' reported energy intake and basal metabolic rate revealed that 76% of respondents were classified as “low-energy reporters” (i.e., they underreported food intake). The descriptive data for the seven dietary components assessed with the use of the food intake questionnaire are shown in Table 3. The patients' daily intake of dietary components was assessed in comparison with the HEA recommendations. This demonstrated that the mean starch intake (141.5 g/day) was well below the recommended 325 g/day. Mean fiber intake was 19 g/day and, therefore, equivalent to the recommended 18 g/day. The recommended total fat intake is approximately 33% of total energy per day, 10% for saturated fat. The recommended daily carbohydrate intake is approximately 50%. Intake of these components was similar to the HEA-recommended intakes. However, the mean (7.0) score for simple sugars (sucrose) was below the daily target of 10% but may be one aspect of dietary behavior that may have been underreported. Table 3. Dietary intake of patients (n=134) Food Percentage per day Grams per day Total fat 31.4 (8.0) 60.7 (38) Saturated fat 11.3 (3.8) 22.1 (15.3) Carbohydrate 46.9 (9.9) 212.1 (132.7) Starch 27.9 123.4 (67) Sugar 7.22 (3.4) 34.0 (34.3) Fiber N/A 16.5 (8.8) Fruit and vegetables N/A 359.2 (243.9) Data are expressed as mean (S.D.).