Physical Activity, Cardiorespiratory Fitness, and Population-Attributable Risk.

Abstract Objective To determine population-attributable risk (PAR) and exposure impact number (EIN) for mortality associated with impaired cardiorespiratory fitness (CRF), physical inactivity, and other risk markers among veteran subjects. Methods The sample included 5890 male subjects (mean age 58±15) who underwent a maximal exercise test for clinical reasons between January 1, 1992, and December 31, 2014. All-cause mortality was the end point. Cox multivariable hazard models were performed to determine clinical, demographic, and exercise-test determinants of mortality. Population-attributable risks and EIN for the lowest quartile of CRF and for inactive behavior were analyzed, accounting for competing events. Results There were 2728 deaths during a mean ± standard deviation follow-up period of 9.9±5.8 years. Having low CRF ( Conclusion Both higher CRF and physical activity provide protection against all-cause mortality in subjects referred for exercise testing for clinical reasons. Encouraging physical activity with the aim of increasing CRF would have a significant impact on reducing mortality.