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: 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)). 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.
Project description:Limited data exists on the interrelationships between physical activity (PA), sedentary behaviors and sleep concerning cardiometabolic risk factors in aged adults at high cardiovascular disease risk. Our aim was to examine independent and joint associations between time spent in leisure-time PA, sedentary behaviors and sleep on the prevalence of obesity, type 2 diabetes (T2D) and components of the metabolic syndrome (MetS) in Mediterranean individuals at high cardiovascular risk. Cross-sectional analyses were performed on baseline data from 5776 Spanish adults (aged 55-75y in men; 60-75y in women) with overweight/obesity and MetS, from October 2013 to October 2016, in the PREDIMED-PLUS trial. Employing multivariable-adjusted Cox regression with robust variance and constant time (given the cross-sectional design), higher prevalence of obesity, T2D and abdominal obesity as component of the MetS were associated with greater time in TV-viewing (Relative Risk, RR: 1.02, 95%CI: 1.01, 1.03; RR:1.04, 95%CI: 1.02, 1.06 and RR: 1.01 95%CI: 1.00, 1.02; respectively, all P < .01). Conversely, greater time in moderate-vigorous PA (MVPA) was associated with lower prevalence of obesity, T2D, abdominal obesity and low HDL-cholesterol (RR: 0.95, 95%CI: 0.93, 0.97; RR: 0.94, 95%CI: 0.89, 0.99; RR: 0.97, 95%CI: 0.96, 0.98; and RR: 0.95, 95%CI: 0.91, 0.99, respectively, all P < .05). For these outcomes, theoretically substituting 1-h/day of MVPA for 1-h/day TV-viewing was also significantly associated with lower prevalence (RR 0.91 to 0.97, all P < .05). Similar lower RR in these outcomes was observed when substituting 1-h/day of MVPA for 1-h/day of sleeping. Longer time watching TV and not meeting MVPA recommendations were jointly associated with higher RR of the prevalence of obesity and T2D. We concluded that, in senior individuals at high cardiovascular risk, greater time spent on MVPA and fewer on sedentary behaviors was inversely associated with prevalence of obesity, T2D, and some of the components of MetS.
Project description:Sedentary behavior is associated with cardiovascular disease, diabetes mellitus, and cancer morbidity, and watching television (TV) is an important sedentary behavior. The aim of this study is to clarify the association between TV viewing time and chronic obstructive pulmonary disease (COPD)-related mortality in Japanese adults.Using the Cox proportional hazard model, we assessed COPD-related mortality by TV viewing time in a national cohort of 33 414 men and 43 274 women without cancer, stroke, myocardial infarction, or tuberculosis at baseline (1988-1990).The median follow-up was 19.4 years; 244 men and 34 women died of COPD. Men watching ?4 hours/day of TV were more likely to die of COPD than those watching <2 hours/day (hazard ratio 1.63; 95% confidence interval, 1.04-2.55), independent of major confounders. No association was found in women.Avoiding a sedentary lifestyle, particularly prolonged TV viewing, may help in preventing death from COPD among men.
Project description:Discretionary screen time (time spent viewing a television or computer screen during leisure time) is an important contributor to total sedentary behaviour, which is associated with increased risk of mortality and cardiovascular disease (CVD). The aim of this study was to determine whether the associations of screen time with cardiovascular disease and all-cause mortality were modified by levels of cardiorespiratory fitness, grip strength or physical activity.In total, 390,089 participants (54% women) from the UK Biobank were included in this study. All-cause mortality, CVD and cancer incidence and mortality were the main outcomes. Discretionary television (TV) viewing, personal computer (PC) screen time and overall screen time (TV?+?PC time) were the exposure variables. Grip strength, fitness and physical activity were treated as potential effect modifiers.Altogether, 7420 participants died, and there were 22,210 CVD events, over a median of 5.0 years follow-up (interquartile range 4.3 to 5.7; after exclusion of the first 2 years from baseline in the landmark analysis). All discretionary screen-time exposures were significantly associated with all health outcomes. The associations of overall discretionary screen time with all-cause mortality and incidence of CVD and cancer were strongest amongst participants in the lowest tertile for grip strength (all-cause mortality hazard ratio per 2-h increase in screen time (1.31 [95% confidence interval: 1.22-1.43], p?<?0.0001; CVD 1.21 [1.13-1.30], p?=?0.0001; cancer incidence 1.14 [1.10-1.19], p?<?0.0001) and weakest amongst those in the highest grip-strength tertile (all-cause mortality 1.04 [0.95-1.14], p?=?0.198; CVD 1.05 [0.99-1.11], p?=?0.070; cancer 0.98 [0.93-1.05], p?=?0.771). Similar trends were found for fitness (lowest fitness tertile: all-cause mortality 1.23 [1.13-1.34], p?=?0.002 and CVD 1.10 [1.02-1.22], p?=?0.010; highest fitness tertile: all-cause mortality 1.12 [0.96-1.28], p?=?0.848 and CVD 1.01 [0.96-1.07], p?=?0.570). Similar findings were found for physical activity for all-cause mortality and cancer incidence.The associations between discretionary screen time and adverse health outcomes were strongest in those with low grip strength, fitness and physical activity and markedly attenuated in those with the highest levels of grip strength, fitness and physical activity. Thus, if these associations are causal, the greatest benefits from health promotion interventions to reduce discretionary screen time may be seen in those with low levels of strength, fitness and physical activity.
Project description:BACKGROUND:Evidence is suggestive of sedentary behaviour being associated with an increased risk of endometrial cancer, but the evidence base is too limited to draw any conclusions for other cancers. The aim of the study was to investigate the association between recreational screen time and site-specific cancer risk. METHODS:We analysed data from the prospective UK Biobank cohort study. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between daily recreational screen time (including television (TV) viewing time, computer use time and total screen time) and site-specific cancer risk. Partition models and isotemporal substitution models investigated the impact of substituting recreational screen time with physical activity. RESULTS:During a mean follow-up of 7.6?years, 28,992 incident cancers were identified among 470,578 adults. A 1-h increase in daily TV viewing time was associated with higher risks of oropharyngeal, oesophago-gastric and colon cancer in fully adjusted models. Participants who reported ?1, compared with 1-???3, hours/day of TV viewing time had lower risks of lung, breast, and oesophago-gastric cancer. Findings were inconsistent for daily recreational computer use and daily total recreational screen time. The majority of observed associations were small, and were attenuated after excluding cancers diagnosed within the first two years of follow-up, except for oesophago-gastric and colon cancers (HR 1.05, 95% CI: 1.01, 1.10; and HR 1.04, 95% CI: 1.01, 1.07 per 1-h increase in daily TV viewing time, respectively). However, isotemporal substitution models showed reduced risk of some site-specific (oropharyngeal, lung, breast and colorectal) cancers when replacing 1-h/day of TV viewing with 1-h of moderate-intensity physical activity or walking. CONCLUSIONS:Our findings show that daily recreational screen time, particularly TV viewing, was associated with small increased risks of oesophago-gastric and colon cancer. Replacing 1-h/day of TV viewing with 1-h of moderate-intensity physical activity or walking was associated with lower risk of oropharyngeal, lung, breast and colorectal cancers. Further research from other large prospective cohort studies is required, while mechanistic research is warranted to enhance the biological plausibility of these findings.
Project description:PURPOSE:Endometrial cancer (EC) survivors are the second largest group of female cancer survivors in the USA, with high prevalence of obesity and physical inactivity. While higher pre-diagnosis body mass index (BMI) has been associated with higher all-cause and disease-specific mortality, pre-diagnosis physical activity has shown mixed evidence of an association with mortality. However, the association between BMI, physical activity, and TV viewing measured after diagnosis and mortality risk among EC survivors is unknown. METHODS:We identified 580 women with EC in the NIH-AARP Diet and Health Study who completed a post-diagnosis questionnaire on BMI, leisure time moderate- to vigorous-intensity physical activity (MVPA), and TV viewing. We used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality. RESULTS:With a median follow-up time of 7.1 years, we observed 91 total deaths. We found a positive association between BMI ([Formula: see text] = 2.14, 95% CI 1.08-4.24 and mortality, and no statistically significant association between TV viewing (HR5+ vs. <3 h/day = 1.46, 95% CI 0.86-2.46) and mortality nor MVPA with mortality (HR15+ vs. 0 MET h/week = 0.72, 95% CI 0.43-1.21) after adjusting for tumor characteristics and demographic factors. Further adjustment for lifestyle and health status attenuated BMI associations ([Formula: see text] = 1.47, 95% CI 0.71-3.07), but strengthened the association between TV viewing and mortality (HR5+ vs. <3 h/day = 2.28, 95% CI 1.05-4.95). CONCLUSIONS:Our results suggest that higher post-diagnosis BMI and TV viewing may be associated with higher mortality risk among EC patients, but that there may be complicated interrelationships between lifestyle factors of BMI, PA, and TV viewing and the mediating role of health status that need to be clarified.
Project description:<h4>Objectives</h4>The aim of this study was to test the mediating role of perceived discrimination and stress on associations between perceived neighborhood social environment (PNSE) and TV viewing.<h4>Methods</h4>Baseline data were used for 4716 participants (mean age = 55.1 y; 63.4% female) in the Jackson Heart Study (JHS), a large prospective cohort study of African Americans in Jackson, Mississippi. One binary TV viewing outcome was created: ?4 h/day versus <4 h/day. PNSE variables included neighborhood violence, problems (higher value = more violence/problems), and social cohesion (higher value = more cohesion). Mediators included perceived lifetime discrimination, daily discrimination, and chronic stress (higher value = greater discrimination/stress). Multivariable regression was used with bootstrap-generated 95% bias-corrected confidence intervals (BC CIs) to test for mediation adjusting for demographics, health-related and psychosocial factors, and population density.<h4>Results</h4>Neighborhood violence, problems, and social cohesion were indirectly associated with TV viewing through lifetime discrimination (<i>OR</i> = 1.03, 95%<i>BC CI</i> = 1.00, 1.07; <i>OR</i> = 1.03, 95%<i>BC CI</i> = 0.99, 1.06 [marginal]; <i>OR</i> = 0.98, 95%<i>BC CI</i> = 0.94, 0.99, respectively) and chronic stress (<i>OR</i> = 0.95, 95%<i>BC CI</i> = 0.90, 0.99; <i>OR</i> = 0.96, 95%<i>BC CI</i> = 0.92, 0.99; <i>OR</i> = 1.05, 95%<i>BC CI</i> = 1.01, 1.10, respectively). Daily discrimination was neither directly nor indirectly associated with TV viewing.<h4>Conclusions</h4>Each PNSE variable was indirectly associated with TV viewing via lifetime discrimination and perceived stress, but not with daily discrimination among JHS participants. Unexpected directionality of mediating effects of lifetime discrimination and chronic stress should be replicated in future studies. Further research is also needed to pinpoint effective community efforts and physical environmental policies (e.g., installing bright street lights, community policing) to reduce adverse neighborhood conditions and psychosocial factors, and decrease TV viewing and subsequent cardiovascular disease risk.
Project description:INTRODUCTION:TV viewing is the most prevalent sedentary behavior and is associated with increased risk of cardiovascular disease and cancer mortality, but the association with other leading causes of death is unknown. This study examined the association between TV viewing and leading causes of death in the U.S. METHODS:A prospective cohort of 221,426 individuals (57% male) aged 50-71 years who were free of chronic disease at baseline (1995-1996), 93% white, with an average BMI of 26.7 (SD=4.4) kg/m(2) were included. Participants self-reported TV viewing at baseline and were followed until death or December 31, 2011. Hazard ratios (HRs) and 95% CIs for TV viewing and cause-specific mortality were estimated using Cox proportional hazards regression. Analyses were conducted in 2014-2015. RESULTS:After an average follow-up of 14.1 years, adjusted mortality risk for a 2-hour/day increase in TV viewing was significantly higher for the following causes of death (HR [95% CI]): cancer (1.07 [1.03, 1.11]); heart disease (1.23 [1.17, 1.29]); chronic obstructive pulmonary disease (1.28 [1.14, 1.43]); diabetes (1.56 [1.33, 1.83]); influenza/pneumonia (1.24 [1.02, 1.50]); Parkinson disease (1.35 [1.11, 1.65]); liver disease (1.33 [1.05, 1.67]); and suicide (1.43 [1.10, 1.85]. Mortality associations persisted in stratified analyses with important potential confounders, reducing causation concerns. CONCLUSIONS:This study shows the breadth of mortality outcomes associated with prolonged TV viewing, and identifies novel associations for several leading causes of death. TV viewing is a prevalent discretionary behavior that may be a more important target for public health intervention than previously recognized. TRIAL REGISTRATION:ClinicalTrials.gov number, NCT00340015.
Project description:Simultaneously define diet, physical activity, television (TV) viewing, and sleep duration across cardiometabolic disease groups, and investigate clustering of non-diet lifestyle behaviours.Cross-sectional observational study.22 UK Biobank assessment centres across the UK.502,664 adults aged 37-63 years old, 54% women. 4 groups were defined based on disease status; 'No disease' (n=103,993), 'cardiovascular disease' (CVD n=113,469), 'Type 2 diabetes without CVD' (n=4074) and 'Type 2 diabetes + CVD' (n=11,574).Diet, physical activity, TV viewing and sleep duration.People with 'CVD' report low levels of physical activity (<918 MET min/week, OR (95% CI) 1.23 (1.20 to 1.25)), high levels of TV viewing (>3 h/day; 1.42 (1.39 to 1.45)), and poor sleep duration (<7, >8 h/night; 1.37 (1.34 to 1.39)) relative to people without disease. People with 'Type 2 diabetes + CVD' were more likely to report low physical activity (1.71 (1.64 to 1.78)), high levels of TV viewing (1.92 (1.85 to 1.99)) and poor sleep duration (1.52 (1.46 to 1.58)) relative to people without disease. Non-diet behaviours were clustered, with people with 'CVD' or 'Type 2 diabetes + CVD' more likely to report simultaneous low physical activity, high TV viewing and poor sleep duration than those without disease (2.15 (2.03 to 2.28) and 3.29 (3.02 to 3.58), respectively). By contrast, 3 in 4 adults with 'Type 2 diabetes', and 2 in 4 adults with 'CVD' have changed their diet in the past 5 years, compared with only 1 in 4 in the 'No disease' group. Models were adjusted for gender, age, body mass index, Townsend Deprivation Index, ethnicity, alcohol intake, smoking and meeting fruit/vegetable guidelines.Low physical activity, high TV and poor sleep duration are prominent unaddressed high-risk characteristics of both CVD and type 2 diabetes, and are likely to be clustered together.
Project description:<h4>Importance</h4>Although the associations between processed meat intake and cardiovascular disease (CVD) and all-cause mortality have been established, the associations of unprocessed red meat, poultry, or fish consumption with CVD and all-cause mortality are still uncertain.<h4>Objective</h4>To identify the associations of processed meat, unprocessed red meat, poultry, or fish intake with incident CVD and all-cause mortality.<h4>Design, setting, and participants</h4>This cohort study analyzed individual-level data of adult participants in 6 prospective cohort studies in the United States. Baseline diet data from 1985 to 2002 were collected. Participants were followed up until August 31, 2016. Data analyses were performed from March 25, 2019, to November 17, 2019.<h4>Exposures</h4>Processed meat, unprocessed red meat, poultry, or fish intake as continuous variables.<h4>Main outcomes and measures</h4>Hazard ratio (HR) and 30-year absolute risk difference (ARD) for incident CVD (composite end point of coronary heart disease, stroke, heart failure, and CVD deaths) and all-cause mortality, based on each additional intake of 2 servings per week for monotonic associations or 2 vs 0 servings per week for nonmonotonic associations.<h4>Results</h4>Among the 29 682 participants (mean [SD] age at baseline, 53.7 [15.7] years; 13 168 [44.4%] men; and 9101 [30.7%] self-identified as non-white), 6963 incident CVD events and 8875 all-cause deaths were adjudicated during a median (interquartile range) follow-up of 19.0 (14.1-23.7) years. The associations of processed meat, unprocessed red meat, poultry, or fish intake with incident CVD and all-cause mortality were monotonic (P for nonlinearity???.25), except for the nonmonotonic association between processed meat intake and incident CVD (P for nonlinearity?=?.006). Intake of processed meat (adjusted HR, 1.07 [95% CI, 1.04-1.11]; adjusted ARD, 1.74% [95% CI, 0.85%-2.63%]), unprocessed red meat (adjusted HR, 1.03 [95% CI, 1.01-1.06]; adjusted ARD, 0.62% [95% CI, 0.07%-1.16%]), or poultry (adjusted HR, 1.04 [95% CI, 1.01-1.06]; adjusted ARD, 1.03% [95% CI, 0.36%-1.70%]) was significantly associated with incident CVD. Fish intake was not significantly associated with incident CVD (adjusted HR, 1.00 [95% CI, 0.98-1.02]; adjusted ARD, 0.12% [95% CI, -0.40% to 0.65%]). Intake of processed meat (adjusted HR, 1.03 [95% CI, 1.02-1.05]; adjusted ARD, 0.90% [95% CI, 0.43%-1.38%]) or unprocessed red meat (adjusted HR, 1.03 [95% CI, 1.01-1.05]; adjusted ARD, 0.76% [95% CI, 0.19%-1.33%]) was significantly associated with all-cause mortality. Intake of poultry (adjusted HR, 0.99 [95% CI, 0.97-1.02]; adjusted ARD, -0.28% [95% CI, -1.00% to 0.44%]) or fish (adjusted HR, 0.99 [95% CI, 0.97-1.01]; adjusted ARD, -0.34% [95% CI, -0.88% to 0.20%]) was not significantly associated with all-cause mortality.<h4>Conclusions and relevance</h4>These findings suggest that, among US adults, higher intake of processed meat, unprocessed red meat, or poultry, but not fish, was significantly associated with a small increased risk of incident CVD, whereas higher intake of processed meat or unprocessed red meat, but not poultry or fish, was significantly associated with a small increased risk of all-cause mortality. These findings have important public health implications and should warrant further investigations.
Project description:There is a growing problem of physical inactivity in America, and approximately a quarter of the population report being completely sedentary during their leisure time. In the U.S., TV viewing is the most common leisure-time activity. Stepping in place during TV commercials (TV Commercial Stepping) could increase physical activity. The purpose of this study was to examine the feasibility of incorporating physical activity (PA) into a traditionally sedentary activity, by comparing TV Commercial Stepping during 90 min/d of TV programming to traditional exercise (Walking).A randomized controlled pilot study of the impact of 6 months of TV Commercial Stepping versus Walking 30 min/day in adults was conducted. 58 sedentary, overweight (body mass index 33.5?±?4.8 kg/m2) adults (age 52.0?±?8.6 y) were randomly assigned to one of two 6-mo behavioral PA programs: 1) TV Commercial Stepping; or 2) Walking 30 min/day. To help facilitate behavior changes participants received 6 monthly phone calls, attended monthly meetings for the first 3 months, and received monthly newsletters for the last 3 months. Using intent-to-treat analysis, changes in daily steps, TV viewing, diet, body weight, waist and hip circumference, and percent fat were compared at baseline, 3, and 6 mo. Data were collected in 2010-2011, and analyzed in 2011.Of the 58 subjects, 47 (81%) were retained for follow-up at the completion of the 6-mo program. From baseline to 6-mo, both groups significantly increased their daily steps [4611?±?1553 steps/d vs. 7605?±?2471 steps/d (TV Commercial Stepping); 4909?±?1335 steps/d vs. 7865?±?1939 steps/d (Walking); P?<?0.05] with no significant difference between groups. TV viewing and dietary intake decreased significantly in both groups. Body weight did not change, but both groups had significant decreases in percent body fat (3-mo to 6-mo), and waist and hip circumference (baseline to 6-mo) over time.Participants in both the TV Commercial Stepping and Walking groups had favorable changes in daily steps, TV viewing, diet, and anthropometrics. PA can be performed while viewing TV commercials and this may be a feasible alternative to traditional approaches for increasing daily steps in overweight and obese adults.This study is registered at ClinicalTrials.gov, NCT01342471.