Abstract
Introduction: Regular physical activity is associated with longevity in adults receiving hemodialysis, but it is uncertain whether this association varies by causal pathways (cardiovascular and noncardiovascular).
Methods: DIET-HD was a prospective, multinational study of adults undergoing hemodialysis across Europe and Argentina. We classified participants as physically inactive, occasionally active (irregularly to once a week), or frequently active (twice a week or more), using a self-reported questionnaire. Potential confounders were balanced across exposure groups using propensity scores. Weighted Cox proportional hazards models with double robust estimators evaluated the association between physical activity and all cause, cardiovascular, and noncardiovascular mortality.
Results: Of 8043 participants in DIET-HD, 6147 (76%) had information on physical activity. A total of 2940 (48%) were physically inactive, 1981 (32%) occasionally active, and 1226 (20%) frequently active. In a median follow-up of 3.8 years (19,677 person-years), 2337 (38%) deaths occurred, including 1050 (45%) from cardiovascular causes. After propensity score weighting, occasional physical activity was associated with lower all-cause (adjusted hazard ratio [aHR] = 0.80, 95% CI = 0.72-0.89), cardiovascular (aHR = 0.82, 95% CI = 0.70-0.96), and noncardiovascular (aHR = 0.81, 95% CI = 0.69-0.94) mortality compared with inactivity. Frequent physical activity was associated with lower all-cause (aHR = 0.82, 95% CI = 0.71-0.95) and cardiovascular (aHR = 0.77, 95% CI = 0.62-0.94) mortality, but not noncardiovascular mortality (aHR = 0.88, 95% CI = 0.72-1.08). A dose-dependent association of physical activity with cardiovascular death was observed (P trend = 0.01).
Conclusion: Compared with self-reported physical inactivity, occasional and frequent physical activities were associated, dose dependently, with lower cardiovascular mortality in adults receiving hemodialysis.