Sedentary behaviour and risk of all-cause, cardiovascular and cancer mortality, and incident type 2 diabetes: a systematic review and dose response meta-analysis

Abstract

Purpose: To estimate the strength and shape of the dose–response relationship between sedentary behaviour and all-cause, cardiovascular disease (CVD) and cancer mortality, and incident type 2 diabetes (T2D), adjusted for physical activity (PA). Data Sources: Pubmed, Web of Knowledge, Medline, Embase, Cochrane Library and Google Scholar (through September-2016); reference lists. Study Selection: Prospective studies reporting associations between total daily sedentary time or TV viewing time, and ≥ one outcome of interest. Data Extraction: Two independent reviewers extracted data, study quality was assessed; corresponding authors were approached where needed. Data Synthesis: Thirty-four studies (1,331,468 unique participants; good study quality) covering 8 exposure-outcome combinations were included. For total sedentary behaviour, the PA-adjusted relationship was non-linear for all-cause mortality (RR per 1 h/day: were 1.01 (1.00–1.01) ≤ 8 h/day; 1.04 (1.03–1.05) > 8 h/day of exposure), and for CVD mortality (1.01 (0.99–1.02) ≤ 6 h/day; 1.04 (1.03–1.04) > 6 h/day). The association was linear (1.01 (1.00–1.01)) with T2D and non-significant with cancer mortality. Stronger PA-adjusted associations were found for TV viewing (h/day); non-linear for all-cause mortality (1.03 (1.01–1.04) ≤ 3.5 h/day; 1.06 (1.05–1.08) > 3.5 h/day) and for CVD mortality (1.02 (0.99–1.04) ≤ 4 h/day; 1.08 (1.05–1.12) > 4 h/day). Associations with cancer mortality (1.03 (1.02–1.04)) and T2D were linear (1.09 (1.07–1.12)). Conclusions: Independent of PA, total sitting and TV viewing time are associated with greater risk for several major chronic disease outcomes. For all-cause and CVD mortality, a threshold of 6–8 h/day of total sitting and 3–4 h/day of TV viewing was identified, above which the risk is increased.Electronic supplementary materialThe online version of this article (10.1007/s10654-018-0380-1) contains supplementary material, which is available to authorized users.

Direct healthcare costs of sedentary behaviour in the UK

“…Nonetheless, it is interesting to note that the PAFs for type 2 diabetes, CVD and all-cause mortality are of the same order of magnitude (ie, type 2 diabetes > all-cause mortality > CVD). The PAFs for CVD are similar (5% [95% CI 1% to 8%] from Patterson et al 4 vs 4.9% [95% CI 1.8% to 7.9%] in the present study). This indicates that although the studies differ in their definition of sedentary behaviour and in the methods used, there is considerable agreement in the observed pattern of the relationships.…”

“…Patterson et al 4 also calculated PAFs for sedentary behaviour in a recent meta-analysis, where the exposure was television viewing time and the methodology (using a Monte Carlo microsimulation) was somewhat different. Thus, it is difficult to compare these estimates.…”

“…National guidelines recommend minimising time spent sedentary3 without specifying how many hours/day of sitting might be harmful. A recent meta-analysis reported that spending 6–8 hours/day sedentary increases future risk of all-cause and cardiovascular mortality 4. In this study, we defined sedentary behaviour as spending at least six hours of waking time sedentary.…”

Postdiagnosis sedentary behavior and health outcomes in cancer survivors: A systematic review and meta‐analysis

“…1 Sedentary behavior, defined as any waking behavior characterized by an energy expenditure ≤1.5 metabolic equivalents of task while in a sitting, reclining, or lying posture, 2,3 has been proposed as a risk factor for several health outcomes in cancer survivors. [5][6][7][8] For instance, in persons who are cancer-free at baseline, increased sedentary time has been associated with higher incidence of cardiovascular disease (CVD), 9 metabolic disorders, 9 several types of cancer, 10 and higher all-cancer as well as all-cause mortality, after adjustment for potential confounding factors, including MVPA. [5][6][7][8] For instance, in persons who are cancer-free at baseline, increased sedentary time has been associated with higher incidence of cardiovascular disease (CVD), 9 metabolic disorders, 9 several types of cancer, 10 and higher all-cancer as well as all-cause mortality, after adjustment for potential confounding factors, including MVPA.…”

Reducing sedentary behaviour in the workplace

“…However, baseline daily sitting in the SMArT Work trial was 9.7 hours daily. At 12 months, participants were still sitting on average more than the 6-8 hours daily, which is associated with greater risk of all cause and cardiovascular disease mortality 8. Importantly, no change in employees’ physical activity was observed; reductions in sedentary behaviour seemed to be entirely related to standing more at work.…”