Physical activity and cause-specific mortality: the Rotterdam Study

Background: Physical activity (PA) is associated with lower risk for all-cause mortality. However, in elderly people, it remains unknown which types of PA are associated with mortality and whether the association between PA and mortality differs by cause of death. Methods: We assessed the association of total PA, walking, cycling, domestic work, sports and gardening with all-cause mortality, and the association of total PA with cause-specific mortality, using Cox proportional hazard models among 7225 older adults (mean age: 70 years) from the prospective population-based Rotterdam Study. Deaths were classified as due to cardiovascular diseases (CVDs), cancer, infections, external causes, dementia, chronic lung diseases or other causes. Activities were categorized into tertiles (lowest tertile as reference). To account for the possibility of reverse causation, we excluded the first 5 and 10 years of follow-up. Results: Over a median of 13.1 years of follow-up (interquartile range: 8.4-14.6 years), 3261 participants died. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) associated with high total PA compared with low were 0.69 (0.63, 0.75), 0.69 (0.58, 0.81), 0.44 (0.27, 0.71), 0.47 (0.32, 0.71) and 0.56 (0.46, 0.69) for mortality from all causes, CVDs, chronic lung diseases, infections and other causes, respectively. With longer exclusion times, the strength of these associations was attenuated. All PA types were associated with lower all-cause mortality risk. Conclusions: Engagement in higher PA levels was associated with lower risk of mortality from CVDs, chronic lung diseases, infections and other causes. Participating in any PA might reduce mortality risk in older adults.