Leisure-time and occupational physical activity and health outcomes in cardiovascular disease

Objective In healthy populations, leisure-time physical activity (LTPA) improves health outcomes, while, paradoxically, occupational physical activity (OPA) is associated with detrimental health effects. This study aimed to investigate the associations of LTPA and OPA with mortality, cardiovascular events and type 2 diabetes (T2D) in patients with cardiovascular disease (CVD). Methods In 7058 outpatients with CVD (age 61 +/- 10 years, 75% male) from the prospective Utrecht Cardiovascular Cohort-Second Manifestations of ARTerial disease cohort, Cox models were used to quantify the associations between self-reported LTPA and OPA and all-cause mortality, cardiovascular events and T2D. Results Over 8.6 years (IQR: 4.6-12.5) of follow-up, 1088 vascular events, 1254 deaths and 447 incident T2D cases occurred. The top LTPA quarter had a lower risk of all-cause mortality (HR 0.63, 95% CI 0.54 to 0.74), recurrent cardiovascular events (HR 0.72, 95% CI 0.60 to 0.84) and incident T2D (HR 0.71, 95% CI 0.55 to 0.93), compared with the lowest quarter. The continuous LTPA associations were reverse J-shaped for all-cause mortality and vascular events and linear for T2D. OPA (heavy manual vs sedentary) showed a trend towards an increased risk of all-cause mortality (HR 1.08, 95% CI 0.86 to 1.35), cardiovascular events (HR 1.15, 95% CI 0.91 to 1.45) and T2D (HR 1.04, 95% CI 0.72 to 1.50). The detrimental effects of higher OPA were more pronounced in men, never-smokers, people with higher education and active employment. Conclusions In patients with CVD, LTPA was associated with lower risk of all-cause mortality, recurrent cardiovascular events and incident T2D. In contrast, OPA seemed to increase the risk of these outcomes. These findings support the existence of a physical activity paradox in patients with CVD.