Sedentary behavior and the risk of stroke: A systematic review and dose-response meta-analysis

The sedentary behavior in people's daily life has continued to increase in recent years, causing many studies to focus on its relationship with diseases. Several studies have shown that sedentary behavior is an independent risk factor for cardiovascular disease and metabolic disease. Therefore, we performed a meta-analysis to assess the association between sedentary behavior and the risk of stroke.Two independent investigators searched for prospective cohort studies on the association between sedentary behavior and stroke risk, published before February 2022. We pooled adjusted effect size and performed the dose-response analysis by random-effect model. Seven studies with 677,614 participants and 15,135 stroke events during a median follow-up of 12.2 years were included. The pooled hazard ratio (HR) of stroke was 1.16 (95% confidence interval [CI]: 1.09-1.24) with no significant heterogeneity (I2 = 0.0%, p for heterogeneity = 0.983). In dose-response analysis, a nonlinear association between sedentary behavior and stroke risk was discovered. Stroke risk began to increase when sedentary time exceeded 3.7 h/d (HR, 1.01; 95% CI, 0.97-1.05). And when reached 11 h/d, a significantly increased risk of stroke was observed (HR, 1.21; 95% CI 1.12-1.31).A nonlinear association was found in the dose-response analysis, with increased risk only when sedentary time exceeded a certain level. Further research is needed to explain the biological mechanisms by which sedentary time above a certain threshold significantly increases stroke risk. (PROSPERO registration number: CRD42022311544).