The benefits of aerobic fitness in relation to all-cause and cardiovascular mortality is well established; however, the associations of long-term change in cardiorespiratory fitness (CRF) with incident heart failure (HF) and atrial fibrillation (AF) have not been studied before. The Kuopio Ischaemic Heart Disease Risk Factor Study is a prospective cohort comprising men aged 42 to 60 years from the city of Kuopio and its surroundings, with a baseline examination between 1984 and 1989 (V1), a re-examination at 11 years (V2), and up to 15 years of follow-up from V2. CRF, as assessed by VO2max, was measured at both visits using respiratory gas exchange during maximal exercise tolerance test. The difference (ΔVO2max) was estimated as VO2max (V2) - VO2max (V1). Participants with no missing data on both baseline and 11-year exercise test were included (n = 481). The mean ΔVO2max was -5.4 ml/min⋅kg (standard deviation 5.4). During a median follow-up of 14.3 years (interquartile range 13.3 to 15.1), 46 incident HF (9.6%) and 73 incident AF (15.2%) events were recorded. In a multivariate analysis adjusted for baseline age, baseline VO2max, systolic blood pressure, smoking, type 2 diabetes, and cardiovascular disease, per 1 ml/min⋅kg higher ΔVO2max was log linearly associated with incident HF with a 10% relative risk reduction of HF (hazard ratio 0.90, 95% confidence interval 0.83 to 0.97). No significant relation of ΔVO2max with incident AF was observed. In conclusion, overall long-term improvement in CRF is associated with reduced risk of HF, indicating the importance of maintaining good CRF over time.
Copyright © 2018 Elsevier Inc. All rights reserved.