Daily sitting time and all-cause mortality: a meta-analysis

Area of Science:

• Public Health
• Epidemiology
• Occupational Health

Background:

• Sedentary behavior, particularly prolonged sitting, is a growing public health concern.
• Understanding the association between sitting time and mortality is vital for developing health recommendations.

Purpose of the Study:

• To quantify the association between daily total sitting time and all-cause mortality risk.
• To examine dose-response relationships, considering moderate-to-vigorous physical activity.

Main Methods:

• Systematic review and meta-analysis of prospective cohort studies published between 1989 and 2013.
• Inclusion criteria: quantitative sitting time exposure, all-cause mortality outcome, and reported risk estimates.
• Data extraction and random effects modeling for summary estimates.

Main Results:

• Six studies with 595,086 participants and 29,162 deaths were analyzed.
• Higher sitting time was associated with increased all-cause mortality risk, even after adjusting for physical activity.
• An estimated 34% higher mortality risk was observed for individuals sitting 10 hours/day, with a population attributable fraction of 5.9% for sitting time.

Conclusions:

• Increased daily sitting time is linked to a greater risk of all-cause mortality.
• Moderate-to-vigorous physical activity may reduce the detrimental effects of prolonged sitting.
• Findings support establishing clinical and public health recommendations for sitting time.