The predictive value of cardiorespiratory fitness for cardiovascular events in men with various risk profiles: a prospective population-based cohort study

AIMS: Few data exist to show if the prognostic value of peak exercise oxygen consumption (VO2peak) for fatal and non-fatal coronary events is different among men with low and high pre-test probability for cardiovascular disease (CVD). Our objective was to determine whether VO2peak could predict fatal and non-fatal cardiac events in 2361 men aged 42-60 years with and without conventional risk predictors of CVD or with documented CVD during a 13-year follow-up. METHODS AND RESULTS: Maximal oxygen consumption (ml/kg/min) was measured directly by using respiratory gas exchange in a cycle ergometer exercise test. Of 204 CVD deaths, 153 were due to coronary disease and 51 were due to other CVDs. A total of 323 non-fatal coronary events occurred during the follow-up. One metabolic equivalent (MET) increment in VO2peak was related to a decreased risk of coronary death in both healthy (RR=0.82, 95% CI 0.66-0.99) and unhealthy (RR=0.72, 95% CI 0.63-0.82) men. VO2peak was predictive of non-fatal and fatal cardiac events among men with or without known risk factors. In subjects with or without common risk factors, one MET increment amounted to an average decrease of 17-29% in non-fatal and 28-51% in fatal cardiac events, after adjustment for age. VO2peak and smoking represented two strongest independent and consistent risk predictors. CONCLUSIONS: VO2peak can be used as a very powerful predictor of future fatal cardiac events beyond that predicted by many conventional risk factors. On the prognostic consideration, unfit men with unfavourable risk profiles or underlying chronic disease are the risk groups that will benefit most from preventive measures.