What evidence does the Copenhagen City Heart Study provide about physical activity and cardiovascular mortality?
The Copenhagen City Heart Study, conducted by Schnohr et al. (2017) prospectively followed over 12,000 primary prevention patients for over 30 years, and found a 24% reduction in cardiovascular mortality in patients who consistently engaged in light leisure-time physical activity (2-4 hours of LIPA per week) compared to those who were persistently sedentary (<2 hours of LIPA per week). This suggests that any movement during leisure time could potentially have beneficial effects on cardiovascular and all-cause mortality. However, the evidence base has significant methodologic limitations, such as reporting bias and potential inaccuracies in converting self-reported activity to accepted categories, which could impact outcomes. Despite these limitations, the body of evidence indicates a positive association of high magnitude between physical activity and important patient outcomes such as all-cause and cardiovascular mortality. 