Religious coping methods predict depression and quality of life among end-stage renal disease patients undergoing hemodialysis: a cross-sectional study

The sample included ESRD patients undergoing HD in the only two dialysis centers in an area of 34,560 km² (37.3 inhabitants/ km²) in the northern region of Ceará State, Northeast Brazil. Of the total of 188 ESRD patients undergoing HD during July 2015, we included 179 patients who were older than 18 years of age and had been undergoing maintenance HD for more than 3 months. Of these eligible patients, 161 were ultimately included. The reasons for exclusion among eligible patients were refusal to participate (8), cognitive impairment that precluded answering the questionnaire (6) and hospitalization (4). All patients were undergoing conventional HD (three four-hour sessions per week) with polysulfone dialyzers (maximum number of reuses = 12). Written informed consent was obtained from all participants, and the study was approved by the ethics committee of Vale Acaraú University, with which the dialysis centers are associated.

We used the R/S coping scale entitled the Religious Coping Questionnaire (RCOPE), which was developed by Pargament, Koenig and Perez [14]. A version of the scale that was translated into Portuguese translated and culturally adapted to the Brazilian context was validated by Panzini and Bandeira [15]. In its Brazilian version, the instrument contains 87 items comprising positive (66 items) and negative (21 items) R/S coping methods. Positive R/S coping methods are those related to seeking spiritual help; offering help to each other; positively positioning oneself in front of God; and personal quest for spiritual knowledge. To be illustrative, examples of positive R/S coping scale items include the following: “working together with God as a partner to endure through problems” or “looking to God for strength, support, and guidance”. In contrast, negative R/S coping methods are related to negative evaluations of God; negatively positioning oneself in front of God; signs of spiritual tension; and conflict and struggles with God and others. Examples of negative R/S coping scale items include the following: “I feel like God has abandoned me”, or “I am angry with God for letting this happen to me”. The patients were asked to indicate how much or how frequently they used the aforementioned R/S methods of coping. Items were rated on a 5-point scale from 1 (not at all) to 5 (always). Both the positive and negative R/S coping scores were assessed as continuous variables. Higher positive R/S coping scores indicated the use of potentially helpful ways of coping, as they are scored based on questions comprising “positive” methods of R/S coping, while higher negative R/S coping scores can be seen as denoting harmful ways of coping, as they are scored based on items reflecting religious struggle. Overall scores were calculated as the mean of the positive and negative coping scores and varied from 1 to 5, with higher scores indicating more frequent use of each coping strategy.

Depression was evaluated using the 20-item version of the Center for Epidemiologic Studies Depression Scale (CES-D) [16]; on this scale, the respondent reports the frequency of symptoms during the past week. The items on this scale address humor, psychosomatic symptoms and social interactions. Each of the 20 items on this instrument is assigned a value of 0, 1, 2 or 3, with higher scores indicating the presence and persistence of depressive symptoms. A score from 0 to 60 is calculated by summing the scores for each item. A score ≥ 16 has been used to define depression in the general population. We used a score ≥ 18 to define depression, as has been previously validated in a HD population [17].

We used the validated Brazilian version of the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) to measure QOL [18]. This is a well-validated and widely used 36-item questionnaire that addresses eight dimensions of QOL. These dimensions include physical function, in which the patients’ performance in terms of daily activities is evaluated; role-physical, in which the impact of physical health on life is determined; bodily pain, in which pain level and its impact on normal daily activities is identified; general health, in which subjective perceptions of present and future health status and resistance to illness are evaluated; vitality, in which the patient’s feelings about his/her energy level, vitality, and moments of fatigue are determined; social functioning, in which the impact of health on routine social activities is assessed; role-emotional, in which the influence of emotional status on daily activities is identified; and mental health, in which humor and well-being, including depression and anxiety, are assessed. The SF-36 generates scores ranging from 0 (worst) to 100 (best) for each of the eight dimensions.

Demographic data, length of time on dialysis, religious affiliation, type of vascular access and underlying etiology of ESRD were obtained from the dialysis centers’ medical records. Underlying renal diseases were classified according to clinical criteria and not by histopathology. Patients were classified as “married” when they were in a stable union independent of civil status. Through a process of exclusion, all subjects who were not in a stable union were considered unmarried, including divorced/separated, widowed and single patients. Economic class was categorized according to criteria on the instrument issued by the Brazilian Association of Research Institutes [19]. This validated instrument has been used in marketing surveys and population censuses and grades economic class into five subgroups: A (best status) through E (worst status). In addition to income level, the criteria assessed for economic class include educational level of the head of household and ownership of household appliances. Each patient was assigned a low, medium or high risk index based on comorbidity, as described by Khan et al. [20]. Khan’s comorbidity index considers age and the presence of nine comorbidities: diabetes, myocardial infarction, angina pectoris, congestive heart failure, liver cirrhosis, obstructive pulmonary disease, systemic collagen disease, pulmonary fibrosis and visceral malignancy. Laboratory tests for serum creatinine, hemoglobin, albumin, calcium and phosphorus levels were performed. The dose of dialysis delivered was evaluated using a second-generation Kt/V equation, as described by Daugirdas [21].

In our study, R/S coping methods were associated with depression in many ways. First, positive R/S coping scores were lower, while negative R/S scores were higher among depressed patients. These differences were small, but differences of only decimals were validated as clinically significant during the process of development and validation of the RCOPE [14]. Second, there was an inverse correlation between positive R/S coping scores and depression scores, indicating that as the use of positive religious coping methods increase, depression scores tended to decrease. On the other hand, we identified a positive correlation between negative R/S coping scores and depression scores, suggesting that as the use of negative religious coping methods increases, depression scores tend to increase. Third, both positive and negative R/S coping methods were independent predictors of both CES-D scores and the presence of depression. Indeed, negative R/S coping scores were associated with a fivefold increase in the odds of depression in our sample. This finding, which indicated the presence of a correlation between religious aspects and depression, corroborates the results of another Brazilian study [30]. Among ESRD patients, depression is classified as compound depression, which indicates depression occurring in someone with another illness or medical condition. In these cases, resistance to treatment is more likely [5]. Thus, religiosity can be seen as a target for interventions. Multidisciplinary teams at dialysis centers can act, especially through social workers and psychologists, to support and stimulate various types of non-organizational religious activities that are known to promote the use of positive R/S coping methods, such as the reading of religious literature, praying or engagement in spiritual discussion groups. Organizational religious activities may be even more effective because church attendance strengthens patients’ social support systems through interactions with community members, faithful laypersons, and religious leaders. Previous studies have reported that that social support is a mediator of depressive symptoms in HD patients [31] and that religious affiliation is associated with lower rates of depression in some groups [32].

R/S coping methods were also associated with HD patients’ perception of their QOL. We identified positive correlations between positive R/S coping scores and scores related to general health and vitality, and inverse correlations between negative R/S coping scores and scores related to social functioning and mental health. Vitality and social functioning are worthy of further discussion because in addition to the bivariate correlations between scores, vitality and social functioning scores were predicted by positive R/S coping and negative R/S coping scores, respectively, in the multivariate analyses. One study found that R/S coping methods explained nearly 40% of the variance in QOL scores among Muslim patients undergoing HD [33]. The associations between R/S coping methods and both vitality and social functioning has been reported in different cultures. In Taiwan, a study also using the SF-36 found that patients undergoing HD presented higher social functioning scale scores if they had stronger spiritual beliefs when compared with those with no or weak spiritual beliefs (assessed by the Royal Free Interview for Spiritual and Religious Beliefs) [34]. In Canada, a study of HD patients found vitality and social functioning (as assessed using the SF-36) to be positively associated with existential well-being (as assessed using the Spiritual Well-Being Scale) [35]. In Iran, vitality and social functioning scores were lower among HD patients classified as having moderate spiritual well-being relative to those assessed as having high spiritual well-being according to the Spiritual Well-Being Scale [36]. In another study of Brazilian patients in which a brief version of the RCOPE was used, positive R/S coping scores were associated with better social functioning, as assessed using the WHOQOL-BREF, and negative R/S coping was associated with worse social functioning [30]. Based on these convergent results in these two dimensions of QOL, R/S coping can be a target for interventions aiming to improve vitality and social functioning of HD patients. In one interventional study, HD patients were invited to attend weekly meetings with a professional responsible for spiritual support, and after the intervention, a significant improvement in the participants’ QOL was identified [13]. In our opinion, similar results may be obtained if religious concerns are addressed by nephrologists, nurses, social workers and psychologists in dialysis centers.

The main limitation of our study is its cross-sectional design, which precluded the detection of the direction of causality between R/S coping and depression and QOL. We are aware that coping methods are dynamic and that the chronic disease itself, health status and psychological distress can cause changes in patient coping over time. For this reason, longitudinal studies are necessary, especially interventional studies that can show the effects of changes in R/S coping methods on outcomes. Another limitation is the particularities of our sample, which include the following: the participants were rarely diabetic, had low comorbidity indices, were of low economic class and were mostly Catholic. These factors preclude the generalizations of these data to more typical HD samples (older patients, diabetic patients with higher rates of comorbidity) and/or with other religious backgrounds.

In summary, multidisciplinary teams at dialysis centers should interact with patients to minimize religious struggles and stimulate and/or support positive R/S coping methods in an effort to improve QOL and decrease depression among ESRD patients undergoing HD. The feasibility of these interactions strongly depends on the cultural background of the sample. This type of intervention would be difficult to implement in a sample consisting mostly of secular individuals.