Leisure sedentary time of 8 hours or more per day is associated with increased long-term risk for stroke in adults younger than 60 years with low physical activity, according to study results published in Stroke.
Multiple studies have shown that physical activity is associated with lower risk for stroke and that excess sedentary time may increase the risk for cardiovascular morbidity and mortality. Sedentary time is defined as the number of hours spent on the computer, reading, and watching television; leisure sedentary time is specific to the sedentary activities performed when not at work.
The objective of the current study was to determine the association between self-reported leisure sedentary time and stroke.
Using data from 143,180 individuals who participated in the Canadian Community Health Survey between 2000 and 2012, a cohort of healthy patients without prior stroke, heart disease, or cancer, was identified. Leisure sedentary time was stratified into 4 groups, according to self-reported leisure sedentary time per day (<4 hours, 4 to <6 hours, 6 to <8 hours, or ≥8 hours).
During a median follow-up of 9.4 years, there were 2965 stroke events (88.2% ischemic). For individuals younger than 60 years with low physical activity, the risk for stroke was increased among those with 8 hours or more of leisure sedentary time per day compared with those with less than 4 hours per day of leisure sedentary time (adjusted hazard ratio, 4.50; 95% CI, 1.64-1.23).
There was no significant association between any sedentary time category and risk for stroke among individuals aged between 60 and 79 years and those aged 80 years and older.
The findings remained unchanged after adjustment for potential vascular and social confounders, multiple sensitivity analyses, and when accounting for the competing risk for death.
The study had several limitations, including missing data on occupational sedentary time, potential recall bias secondary to assessment of sedentary time using self-reported data, and the lack of data on the association between leisure sedentary time and the risk for hemorrhagic stroke.
“[H]igh sedentary time with low [physical activity] is associated with higher risk of stroke in young individuals. Public health efforts to increase [physical activity], as well as reduce high sedentary time in the young, may contribute to lowering the long-term risk of stroke in this population,” the researchers concluded.
Joundi RA, Patten SB, Williams JVA, Smith EE. Association between excess leisure sedentary time and risk of stroke in young individuals. Stroke. Published online August 19, 2021. doi:10.1161/STROKEAHA.121.034985