Abstract 11866: Cardiorespiratory Fitness and Mortality in Older Adults Age 60 to 90 Years

Abstract

Introduction: With an aging population and advances in technology and surgical interventions, physicians are sometimes faced with difficult treatment decisions for older patients. Invasive treatment options may not be beneficial in older adults with limited survival. Chronological age alone does not fully reflect a patient’s prognosis and should not be the only factor used to guide treatment decisions. In this study, we assessed the association of cardiorespiratory fitness with all-cause mortality among adults age 60 to 90 years. Methods: This retrospective cohort study included patients age 60-90 years who underwent symptom-limited exercise treadmill testing at an integrated health system from 2011 to 2019. Patients were categorized into three age groups: 60-70 years, 70-80 years, and 80-90 years. Cardiovascular fitness was categorized into low fitness (<5 METs), moderate fitness (5-10 METs), and high fitness (>10 METs). Median follow-up was 3.5 years. Hazard ratios (HR) associated with exercise capacity were calculated using multivariable Cox regression models. Results: The study cohort included 40520 patients: 27021 (66.7%) age 60-70 years, 11638 (27.6%) age 70-80 years, and 1861 (4.6%) age 80-90 years. After treadmill testing, 3494 (8.6%) were categorized as low fitness, 21863 (54.0%) as moderate fitness, and 15163 (37.4%) as high fitness. Older age, female sex and presence of cardiovascular risk factors including hypertension, diabetes, and chronic kidney disease were associated with having low fitness. Low fitness and higher chronological age were independently associated with lower survival. Using the age 60-70 years group with high fitness as reference, the age 80-90 group with high fitness had better survival than their younger counterparts with low fitness (age 80-90 high fitness: HR 2.9, 95% CI 1.2-7.2; age 60-70 low fitness HR 4.3, 95% CI 3.1-5.9; age 70-80 low fitness HR 6.8, 95% CI 5.2-8.9). Conclusions: High cardiorespiratory fitness is a strong predictor of survival. When assessing a patient’s prognosis for long-term survival, chronological age alone should not be the only factor considered. Evaluation of cardiorespiratory fitness using treadmill testing may be useful for tailoring prognostic information.