ARTICLE: Fitness and 10-year risk of mortality among adults ≥70 years old at the extremes of cardiovascular disease risk factor burden: the FIT Project
JOURNAL: J Am Coll Cardiol. 2019 Mar 26;73(9). doi: 10.1016/S0735-1097(19)33770-2.
Background: Traditional cardiovascular disease (CVD) risk factors have a decreased predictive strength with increasing age. We sought to determine if fitness could improve risk stratification among older adults at the extremes of CVD risk factor burden.
Methods: We studied 6,509 patients ≥70 years of age without CVD from the Henry Ford Exercise Testing Project (FIT Project). Patients underwent a physician referred treadmill stress test with fitness grouped as <6, 6-9.9, and ≥10 METs. Traditional CVD risk factors (hypertension, hyperlipidemia, diabetes, and smoking) were summed from 0 to ≥3. We calculated adjusted Cox hazard models and Kaplan-Meier survival graphs.
Results: Patients had a mean age of 74.5 ±4 years (52% women) and there were 2,526 deaths over a mean 9.4 ±4.4 years follow-up. The mortality rate per 1,000 person years was approximately 55 for the least fit (<6 METs) and 25 for the most fit (≥10 METs) regardless of the number of risk factors. A higher fitness (A), but not lower number of risk factors (B), was associated with improved survival (Figure). In adjusted Cox models, older persons with ≥3 risk factors who had moderate (6-9.9 METs) and high (≥10 METs) fitness had a reduced mortality hazard of 0.64 (95% CI 0.54-0.76) and 0.47 (95% CI 0.36-0.62), respectively, when compared to the least fit.
Conclusion: Among adults aged ≥70, there was no difference in survival between patients with 0 or ≥3 CVD risk factors, but higher fitness was associated with improved survival regardless of CVD risk factor burden.
Link to abstract online: http://www.onlinejacc.org/content/73/9_Supplement_2/8