Blog | Monday, October 29, 2012

QD: News Every Day--Physical activity doesn't offset sedentary lifestyle


A meta-analysis added some deeper levels of insight into studies that claimed an association between sedentary behavior and chronic diseases, particularly diabetes.

European researchers identified in the literature two cross-sectional and 16 prospective studies (15 of 18 moderate to high-quality) that tallied nearly 800,000 participants.

Results appeared in the November issue of Diabetologia.

The greatest sedentary had a 112% increase in the relative risk (RR) of diabetes compared to the least amount of time (RR 2.12; 95% credible interval [CrI], 1.61 to 2.78). A Bayesian predictive effect and interval was significant only for diabetes.

Also, there was a 147% increase in the RR of cardiovascular events (RR 2.47; 95% CI, 1.44 to 4.24), a 90% increase in the risk of cardiovascular mortality (hazard ratio (HR) 1.90; 95% CrI, 1.36 to 2.66) and a 49% increase in the risk of all-cause mortality (HR 1.49; 95% CrI, 1.14 to 2.03).

"[T]he reported associations were largely independent of physical activity, adding further weight to the concept of sedentary behaviour being a distinct behaviour in its own right," the researchers wrote. "This is an important conclusion because it suggests that the deleterious effects of higher levels of sedentary behaviour are not mediated through lower amounts of MVPA (moderate-to-vigorous intensity physical activity)."