Self-Reported Physical Activity And Outcomes In Individuals With Chronic Kidney Disease

Background: In the general population, higher levels of physical activity are associated with lower risk for cardiovascular events and mortality. Although individuals with CKD are less physically active than individuals without CKD and at increased cardiovascular risk, the association between physical activity and outcomes has not been extensively evaluated in this population. Hypothesis: Lower levels of physical activity will be associated with an increased risk for cardiovascular events and mortality. Methods: We used data from 3935 participants in the Chronic Renal Insufficiency Cohort (CRIC) Study, an ongoing multi-center prospective observational study of adults with CKD enrolled between 2003 and 2008. Self-reported physical activity was assessed at study entry using a self-reported survey. We evaluated two predictors: walking pace and moderate-to-vigorous physical activity (MVPA) MET-hours per week. Outcomes included physician-adjudicated myocardial infarction (MI), stroke, congestive heart failure (CHF), and cardiovascular (CV) death. Cox proportional hazards were used to assess the association of physical activity with outcomes. Results: At baseline, mean age was 57.7 years, 45.2% (1777 of 3935) were women, 33.4% (1314 of 3935) had self-reported cardiovascular disease, mean eGFR was 44.9 ml/min/m 2 , 11.7% (459 of 3914) were in the fastest walk pace group (>3 mph) and median MVPA was 39.0 MET-hours per week. During a median follow-up of 8.9 years, the number of events was 477 for MI, 230 stroke, 843 CHF, and 1022 CV deaths. In fully adjusted models, fastest walk pace was associated with lower risk for each outcome. Those in the highest MVPA quartile had lower risk for MI and CV death, but not stroke or CHF, compared to those who were least active ( Table 1 ). Conclusion: In this cohort of adults with CKD, higher physical activity was protective against cardiovascular events and cardiovascular mortality, which may have important implications for clinical practice and the design of future studies.