Association of Sedentary Lifestyle with All-Cause and Cause-Specific Mortality in Adults with Reduced Kidney Function

Abstract

Key Points Nearly half of individuals with reduced kidney function had sedentary lifestyle, defined as more than 6 hours of sitting a day.Non-Hispanic White individuals and individuals with younger age, obesity, and with diabetes were more likely to have sedentary lifestyles.Spending more than 6 hours a day sedentary increases the future risk of death from all causes and cardiovascular diseases in individuals with reduced kidney function. Background Individuals with CKD tend to have sedentary behavior and decreased physical activity; both are independent predictors of mortality in general population. While physical inactivity correlates to adverse health outcomes in patients with reduced kidney function, it is unclear whether this relationship remains significant for sedentary behavior. Our study purpose was to evaluate the association of sedentary lifestyle with mortality risk in individuals with renal insufficiency. Methods The study population were adult participants of 2007–2016 National Health and Nutrition Examination Survey with eGFR <60 ml/min per 1.73 m2 or self-reporting receiving dialysis (N=1419). Sedentary lifestyle was defined as sedentary time >6 hours per day. Outcome of interest was all-cause and cardiovascular disease (CVD)–related or cancer-related mortality. Results We observed that non-Hispanic White individuals and individuals with younger age and higher educational level were more likely to have sedentary lifestyle. During a median follow-up of 99 (interquartile range, 70–128) months, a total of 458 participants died (3.98 deaths per 1000 person-months); 120 died from CVD and 92 from cancer, respectively. The crude analysis showed that individuals with sedentary lifestyle have higher risk of all-cause and CVD-related but not cancer-related mortality compared with the nonsedentary population. After adjusting for potential confounders, we showed that all-cause mortality and CVD-related mortality were 1.64-fold (95% confidence interval, 1.26 to 2.12) and 1.66-fold (95% confidence interval, 1.03 to 2.67) higher, respectively, in the sedentary population compared with the nonsedentary population. Similar results were observed in the sensitive analyses, in which we excluded individuals with dialysis, eGFR <15 ml/min per 1.73 m2, or mobility disability. Conclusions Our findings suggest that sedentary lifestyle correlated to greater risk of all-cause and CVD-related mortality among individuals with reduced kidney function. Interventions targeting the individuals with risky behaviors may have practical importance for public health.