Fitness, work, and leisure-time physical activity and ischaemic heart disease and all-cause mortality among men with pre-existing cardiovascular disease

Objective Our aim was to study the relative impact of physical fitness, physical demands at work, and physical activity during leisure time on ischaemic heart disease (IHD) and all-cause mortality among employed men with pre-existing cardiovascular disease (CVD). Method We carried out a 30-year follow-up of the Copenhagen Male Study of 274 gainfully employed men, aged 40-59 years who had a history of CVD (ie, myocardial infarction, angina pectoris, and intermittent claudication). We estimated physical fitness [maximal oxygen consumption (VO(2)Max)] using the Astrand cycling test and determined physical work demands and leisure-time physical activity using a self-reported questionnaire. Results Among 274 men with a history of CVD, 93 men died from IHD. Using male employees with a history of CVD and a low level of fitness as the reference group, our Cox analyses adjusted for age, blood pressure, smoking, alcohol consumption, body mass index, diabetes, hypertension, physical work demands, leisure-time physical activity, and social class showed a substantially reduced risk for IHD mortality among employees who were intermediately fit [VO(2)Max range 25-36; hazard ratio (HR) 0.54, 95% confidence interval (95% CI) CI 0.32-0.93] and highly fit (VO(2)Max range 37-50; HR 0.28, 95% CI 0.12-0.66). We found a positive, but statistically non-significant association between physical demands at work and all-cause mortality. Conclusion Among gainfully employed men with pre-existing CVD, a high physical fitness was associated with a substantially reduced risk for IHD and all-cause mortality.