Relationship between Sedentary Behavior and All-cause Mortality in Japanese Chronic Hemodialysis Patients: A Prospective Cohort Study

We investigated the relationship between sedentary behavior and all-cause mortality in patients undergoing hemodialysis. A total of 71 patients (39 men, 32 women, aged 72.1 +/- 11.7 years) were enrolled in this longitudinal study. Their sedentary behavior was measured using a tri-accelerometer that provides relative values per daily wearing time. We classified the sedentary behavior time into 2 groups (under the median: short-sedentary behavior (SB) group; over the median: long-SB group) and compared the groups' clinical parameters. We compared the groups' survival rates by using Kaplan-Meier curves and the log-rank test, and we performed multivariate analyses by a Cox-proportional hazard model to evaluate the relationship between the sedentary behavior and the survival rate. Twenty patients (28.2%) died during the observation period. The survival rate of the short-SB group was significantly higher than that of the long-SB group. Sedentary behavior was thus an important factor for all-cause mortality even after adjusting for confounding factors by a Cox-proportional hazard model. Sedentary behavior is closely linked to all-cause mortality, especially total days and non-hemodialysis days, and reducing sedentary behavior may be beneficial to reduce the all-cause mortality of patients on chronic hemodialysis.