Association of coping strategies with mortality and health-related quality of life in hemodialysis patients: The Japan Dialysis Outcomes and Practice Patterns Study

BACKGROUND Hemodialysis patients are exposed to disease- and treatment-related stresses, and use various coping strategies to deal with these stresses. Although some studies have reported the association of coping strategies with mortality or health-related quality of life (QOL) in some populations, the effect of coping strategies on clinical outcomes in hemodialysis patients remains unclear. We investigated the association in a longitudinal design among Japanese hemodialysis patients. METHODS We examined Japanese hemodialysis patients who participated in the Dialysis Outcomes and Practice Patterns Study (DOPPS) IV, which was conducted between 2009 and 2012. The exposure variable was stress coping strategy, as assessed using subscales in Coping Strategies Inventory Short Form: problem-focused engagement, problem-focused disengagement, emotion-focused engagement, and emotion-focused disengagement. Hazard ratios were estimated using Cox proportional hazard model for all-cause mortality and mean differences for change in health-related QOL in 1 year were estimated using a regression model. RESULTS Among 1,354 patients, only problem-focused engagement was significantly associated with longer survival; other subscales were not associated with all-cause mortality after adjustment for potential confounding factors. In terms of health-related QOL, the subscale of problem-focused engagement was also associated with improvement in physical functioning and mental health among 1,045 patients. Emotion-focused disengagement was associated with deterioration in mental health, but not with change in physical functioning. The other subscales were not associated with change in physical functioning or mental health. CONCLUSIONS Among hemodialysis patients, "problem-focused engagement" coping strategies were associated with longer survival and also with improvement in physical functioning and mental health. To achieve greater longevity and improve QOL in hemodialysis patients under ongoing stresses, problem-focused engagement should be encouraged.