Abstract 9958: Fitness in Young Adulthood is Independently Associated With Improved Survival and Cardiovascular Risk: The CARDIA study

Introduction: Though cardiorespiratory fitness (CRF) is a well-established prognostic marker in older adults, the relationship between changes in CRF during early adulthood and long-term cardiovascular structure, function, and events remain unknown. Hypothesis: CRF and its change over time in young adults is associated with long-term outcome and cardiovascular disease (CVD). Methods: 4,872 American adults age 18-30 years underwent treadmill exercise testing at a baseline study visit in 1985-1986, and 2,472 individuals who underwent repeat treadmill testing 7 years later in CARDIA. Participants were followed for a median of 26.9 years, with assessment of obesity, echocardiographic left ventricular (LV) mass and strain, coronary artery calcification (CAC), and vital status and incident CVD. Incident CVD (cardiovascular death, heart failure, myocardial infarction, peripheral artery disease and stroke) and all-cause mortality were uniformly adjudicated. Results: From 4,872 individuals, 273 (5.6%) died and 193 (4%) experienced CVD events at a median 26.9 year follow-up. After full adjustment, each additional minute of baseline exercise test duration was associated with a 13% lower hazard of death (hazard ratio HR 0.87, 95% CI 0.81-0.92, P<0.0001) and a 9% lower hazard of CVD (HR 0.91, 95% CI 0.84-0.98, P=0.008). Higher baseline fitness was associated with decreased risk of LV hypertrophy (P=0.009) and higher global longitudinal strain (P<0.0001) at Year 25. Fitness was not associated with CAC. A 1-minute reduction in fitness by Year 7 was associated with a 20% increased hazard of death and CVD, along with a greater probability of LV hypertrophy and more impaired strain. There was no association between change in fitness and CAC. Conclusions: Higher fitness at baseline and improvement in fitness early in adulthood are favorably associated with CVD and mortality risk. Fitness and changes in fitness are associated with myocardial hypertrophy and dysfunction, but not CAC. Regular efforts to ascertain and improve CRF in young adulthood may play a critical role in promoting cardiovascular health and interrupting early CVD pathogenesis.