Exercise Capacity, Heart Failure Risk, and Mortality in Older Adults: The Health ABC Study

Introduction Data on the association between exercise capacity and risk for heart failure (HF) in older adults are limited. Methods This study examined the association of exercise capacity, and its change over time, with 10-year mortality and incident HF in 2,935 participants of the Health, Aging, and Body Composition Study without HF at baseline (age, 73.6 [SD=2.9] years; 52.1% women; 41.4% black; 58.6% white). This cohort was initiated in 1997–1998 and exercise capacity was evaluated with a long-distance corridor walk test (LDCW) at baseline and Year 4. Outcomes were collected in 2007–2008 and initial analysis performed in 2014. Results Ten-year incident HF for completers (n=2,245); non-completers (n=331); and those excluded from LDCW for safety reasons (n=359) was 11.4%, 19.2%, and 23.0%, respectively. The corresponding 10-year mortality was 27.9%, 41.1%, and 42.4%. In models accounting for competing mortality, the adjusted subhazard ratio for HF was 1.37 (95% CI=1.00, 1.88; p=0.049) in non-completers and 1.41 (95% CI=1.06, 1.89; p=0.020) in those excluded versus completers. Non-completers (adjusted hazard ratio, 1.49; 95% CI=1.21, 1.84; p<0.001) and those excluded (hazard ratio, 1.27; 95% CI=1.04, 1.55; p=0.016) had elevated mortality. In adjusted models, LDCW performance variables were associated mainly with mortality. Only 20-meter walking speed and resting heart rate retained prognostic value for HF. Longitudinal changes in LDCW did not predict subsequent incident HF or mortality. Conclusions Completing an LDCW is strongly associated with lower 10-year mortality and HF risk in older adults. Therefore, walking capacity may serve as an early risk marker.