Sedentary time and its association with risk for disease incidence, mortality, and hospitalization in adults: a systematic review and meta-analysis.
Level 2 - randomized trial
Systematic review and meta-analysis of prospective cohort and observational studies
PubMed 25599350 · doi:10.7326/M14-1651
What was done
A systematic review and meta-analysis of English-language studies searched across MEDLINE, PubMed, EMBASE, CINAHL, Cochrane Library, Web of Knowledge, and Google Scholar through August 2014. Included studies assessed sedentary behavior in adults, adjusted for physical activity, and evaluated associations with hospitalizations, all-cause mortality, cardiovascular disease, diabetes, or cancer. Quality assessment and data extraction were performed by independent reviewers.
What was found
Forty-seven articles were included (all but 3 were prospective cohort studies). Sedentary time was significantly associated with all-cause mortality (HR 1.240, 95% CI 1.090 to 1.410; 13 studies), cardiovascular disease mortality (HR 1.179, 95% CI 1.106 to 1.257), cardiovascular disease incidence (HR 1.143, 95% CI 1.002 to 1.729), cancer mortality (HR 1.173, 95% CI 1.108 to 1.242; 14 studies), cancer incidence (HR 1.130, 95% CI 1.053 to 1.213), and type 2 diabetes incidence (HR 1.910, 95% CI 1.642 to 2.222; 14 studies). Deleterious associations were more pronounced at lower levels of physical activity than at higher levels.
Why it matters
This review establishes that prolonged sitting is an independent risk factor for major chronic diseases and premature death, demonstrating that physical activity alone may not completely eliminate the hazards of excessive sedentary behavior.
Limits
Forty-six of the 47 studies quantified sedentary time using self-report rather than objective measurement devices. Marked heterogeneity was present across research designs and exposure definitions, and observational designs cannot definitively establish causality or eliminate residual confounding.
Cited by
- supports Sedentary time is an independent risk factor for higher all-cause mortality and increased cancer risk.