Letter to the editor: Interaction between type 2 diabetes polygenic risk and physical activity on cardiovascular outcomes

In a recent article, Lee et al.1 examined the association between genetic risk for type 2 diabetes and physical activity on cardiovascular outcomes. They found that ‘The beneficial effect of physical activity on cardiovascular outcomes disappeared among diabetic individuals with high genetic risk for type 2 diabetes.’ They further showed ‘In this subpopulation, intense physical activity was associated with increased risk of cardiovascular outcomes.’ We believed that Lee’s findings were significant because previous literature has consistently concerned whether high amounts of exercise pose risks to individuals, particularly those at high risk with disease. On the other hand, we also want to emphasize that the proportion of inactive individuals is often higher than those who engage in high amounts of exercise, particularly among those with diabetes.2 Therefore, it is crucial to encourage high-risk individuals to transition from being completely inactive to starting physical activity. Previous literature on the general population examining the relationship between physical activity and cardiovascular disease outcomes has indicated that the risk of cardiovascular disease often shows a ‘curvilinear’ relationship with physical activity.3 This implies that as the amount of physical activity increases, relatively fewer additional benefits are acquired, and the benefits may reach a ceiling at very high physical activity levels.