Sex- and age-specific associations between cardiorespiratory fitness, CVD morbidity and all-cause mortality in 266.109 adults.

The aim was to investigate sex- and age-specific associations between cardiorespiratory fitness, all-cause and cause-specific mortality, and cardiovascular disease (CVD) morbidity. 266.109 participants (47% women, 18-74 years) free from CVD, participating in occupational health service screenings in 1995-2015 were included. CRF was assessed as estimated maximal oxygen consumption (estVO2max) using a submaximal cycle test. Incident cases of first-time CVD event and death from any cause were ascertained through national registers. There were 4244 CVD events and 2750 cases of all-cause mortality during mean 7.6 years follow-up. Male gender, higher age and lower estVO2max were associated with higher all-cause mortality and CVD morbidity incidence rates. Risk reductions with increasing estVO2max were present in all age-groups of men and women. No obvious levelling off in risk was identified in the total cohort. However, women and older age-groups showed no further reduction in higher aggregated estVO2max levels. CVD specific mortality was more associated with estVO2max compared to tumor specific mortality. The risk for all-cause mortality and CVD morbidity decreased by 2.3% and 2.6% per increase in 1 ml·min-1·kg-1 with no significant sex-differences but more pronounced in the three lower estVO2max categories for all-cause mortality (9.1%, 3.8% and 3.3%, respectively). High compared to lower levels of estVO2max was not related to a significantly elevated mortality or morbidity. In this large cohort study, CVD morbidity and all-cause mortality were inversely related to estVO2max in both men and women of all age-groups. Increasing cardiorespiratory fitness is a clear public health priority.