Cardiorespiratory fitness indicators and Life's Essential 8 in individuals with coronary artery disease

Objective To analyze the associations between cardiorespiratory fitness (CRF) indicators and cardiovascular health, assessed through the Life's Essential 8 (LE8) score, in individuals with coronary artery disease (CAD). Patients and methods This cross-sectional study included individuals (aged 50-75 years) with stable CAD were enrolled in the Heart-Brain randomized controlled trial (NCT06214624) from April 2022 to June 2024. Participants underwent a cardiopulmonary exercise test until volitional exhaustion. CRF indicators included peak oxygen consumption (VO2peak), time to exhaustion (TTE), ventilatory anaerobic threshold (VAT), peak oxygen pulse, 60-s heart rate recovery (HRrec) and oxygen uptake efficiency slope (OUES). LE8 score (range 0-100) was calculated as the unweighted average of 8 variables: physical activity, sleep, diet, nicotine exposure, glucose, lipids, body mass index, and blood pressure, as defined by the American Heart Association. We used linear regression models adjusted for sex, age, and education. Results 102 individuals were included (21 females). VO2peak ({beta}std=0.67, P<.001) and TTE ({beta}std=0.64, P<.001) showed strong positive associations with LE8 total score, followed by VAT ({beta}std=0.43, P<.001) and HRrec ({beta}std=0.26, P=.01). No associations were found for OUES ({beta}std=-0.08, P=.54) and peak oxygen pulse ({beta}std=-0.05, P=.72). Conclusion Maximal and submaximal indicators of CRF were positively associated with LE8 in individuals with CAD, yet maximal indicators showed the strongest associations. Notably, TTE demonstrated a similar strength of association with LE8 as VO2peak. These findings have important clinical and research implications as they support TTE as a simpler (than the gold-standard VO2peak), yet informative, marker of cardiovascular health in individuals with CAD.