Identification of illness representational patterns and examining differences of self-care behavior in the patterns in chronic kidney disease

Self-care behavior is considered important for preventing the progression of chronic kidney disease (CKD). Although lifestyle interventions are popular, they have not been sufficiently effective. According to studies on other chronic diseases, illness representation has been found to formulate a pattern, and self-care behavior could differ depending on the pattern, which suggests difference in self-care behavior based on illness representation. This study examined what kind of illness representational patterns exist among CKD patients and whether there is a difference in self-care behavior depending on the pattern. A survey was conducted from the beginning of June to the end of October 2019 on 274 CKD patients who were either outpatients or hospitalized at general hospitals in Western Japan. The Illness Perception Questionnaire-Revised was used to assess illness representation and the Japanese Chronic Kidney Disease Self-Care scale was used to assess self-care behavior. Two-stage cluster analysis was used to identify clusters. Cluster features were examined using analysis of variance and Tukey HSD tests. Differences in self-care behavior scores among identified clusters were investigated. Two hundred and forty-four questionnaires were received, and 212 were analyzed. Participants were aged 64.9±12.9, and the estimated glomerular filtration rate was 33.7±15.8. Three clusters were identified: Cluster 1 represented the difficulty of making sense of the changed condition caused by the disease and easily falling into misunderstanding; Cluster 2 represented patients with disease conditions that impacted their daily life and emotional responses; Cluster 3 represented the controllability and understandability of the disease. Total self-care behavior scores indicated a significant difference between Cluster 1 (52.1 ± 9.7) and Cluster 3 (57.7 ± 8.2). In conclusion, we showed that three representational patterns exist among CKD patients. In addition, a difference was found in self-care behavior depending on the illness representational pattern, suggesting the need to focus on illness representation.