Types of Sedentary Behavior and Risk of Cardiovascular Events and Mortality in Blacks: The Jackson Heart Study.
ABSTRACT: Background Previous cross-sectional studies have shown conflicting results regarding the effects of television viewing and occupational sitting on cardiovascular disease ( CVD ) risk factors. The purpose of this study was to compare the association of both television viewing and occupational sitting with CVD events and all-cause mortality in blacks. Methods and Results Participants included 3592 individuals enrolled in the Jackson Heart Study, a community-based study of blacks residing in Jackson, Mississippi. Television viewing (<2, 2-4, and >4 h/day) and occupational sitting (never/seldom, sometimes, often/always) were self-reported. Over a median follow-up of 8.4 years, there were 129 CVD events and 205 deaths. The highest category of television viewing (>4 h/day) was associated with a greater risk for a composite CVD events/all-cause mortality end point compared with the lowest category (<2 h/day; hazard ratio, 1.49; 95% CI , 1.13-1.97). In contrast, the highest category of occupational sitting (often/always) was not associated with risk for a composite CVD events/all-cause mortality end point compared with the lowest category (never/seldom; hazard ratio, 0.90; 95% CI , 0.69-1.18). Moderate-to-vigorous physical activity moderated the association of television viewing with CVD events/all-cause mortality such that television viewing was not associated with greater risk among those with high moderate-to-vigorous physical activity levels. Conclusions Television viewing was associated with greater risk of CVD events and all-cause mortality, while occupational sitting had no association with these outcomes. These findings suggest that minimizing television viewing may be more effective for reducing CVD and mortality risk in blacks compared with reducing occupational sedentary behavior.
Project description:OBJECTIVES:To determine the impact of sitting and television viewing on life expectancy in the USA. DESIGN:Prevalence-based cause-deleted life table analysis. SETTING:Summary RRs of all-cause mortality associated with sitting and television viewing were obtained from a meta-analysis of available prospective cohort studies. Prevalences of sitting and television viewing were obtained from the US National Health and Nutrition Examination Survey. PRIMARY OUTCOME MEASURE:Life expectancy at birth. RESULTS:The estimated gains in life expectancy in the US population were 2.00 years for reducing excessive sitting to <3 h/day and a gain of 1.38 years from reducing excessive television viewing to <2 h/day. The lower and upper limits from a sensitivity analysis that involved simultaneously varying the estimates of RR (using the upper and lower bounds of the 95% CI) and the prevalence of television viewing (±20%) were 1.39 and 2.69 years for sitting and 0.48 and 2.51 years for television viewing, respectively. CONCLUSION:Reducing sedentary behaviours such as sitting and television viewing may have the potential to increase life expectancy in the USA.
Project description:Sedentary behaviors predominate modern life, yet we do not fully understand the adverse effects of these behaviors on mortality after considering the benefits of moderate-vigorous physical activity (MVPA).We tested the hypotheses that higher amounts of overall sitting time and television viewing are positively associated with mortality and described the independent and combined effects of these sedentary behaviors and MVPA on mortality.In the NIH-AARP Diet and Health Study, we examined 240,819 adults (aged 50-71 y) who did not report any cancer, cardiovascular disease, or respiratory disease at baseline. Mortality was ascertained over 8.5 y.Sedentary behaviors were positively associated with mortality after adjustment for age, sex, education, smoking, diet, race, and MVPA. Participants who reported the most television viewing (?7 h compared with <1 h/d) were at greater risk of all-cause (HR: 1.61; 95% CI: 1.47, 1.76), cardiovascular (HR: 1.85; 95% CI: 1.56, 2.20), and cancer (HR: 1.22; 95% CI: 1.06, 1.40) mortality after adjustment for MVPA. Overall sitting was associated with all-cause mortality. Even among adults reporting high levels of MVPA (>7 h/wk), high amounts of television viewing (?7 h/d) remained associated with increased risk of all-cause (HR: 1.47; 95% CI: 1.20, 1.79) and cardiovascular (HR: 2.00; 95% CI: 1.33, 3.00) mortality compared with those reporting the least television viewing (<1 h/d).Time spent in sedentary behaviors was positively associated with mortality, and participation in high levels of MVPA did not fully mitigate health risks associated with prolonged time watching television. Adults should be encouraged to reduce time spent in sedentary behaviors, when possible, and to participate in MVPA at recommended levels. The NIH-AARP Diet and Health Study was registered at clinicaltrials.gov as NCT00340015.
Project description:Excess sitting is emerging as a novel risk factor for cardiovascular disease, diabetes, mental illness, and all-cause mortality. Physical activity, distinct from sitting, is associated with better sleep and lower risk for OSA, yet relationships among sitting behaviors and sleep/OSA remain unknown. We examined whether total sitting time and sitting while viewing television were associated with sleep duration and quality, OSA risk, and sleepiness.The 2013 National Sleep Foundation Sleep in America Poll was a cross-sectional study of 1,000 adults aged 23 to 60 years. Total sitting time, time watching television while sitting, sleep duration and quality, OSA risk, and daytime sleepiness were assessed.After adjusting for confounding factors (including BMI and physical activity), each additional hour per day of total sitting was associated with greater odds of poor sleep quality (OR [95% CI] = 1.06 [1.01, 1.11]) but not with other sleep metrics (including sleep duration), OSA risk, or daytime sleepiness. For television viewing while sitting, each additional hour per day was associated with greater odds of long sleep onset latency (≥ 30 min) (OR = 1.15 [1.04, 1.27]), waking up too early in the morning (OR = 1.12 [1.03, 1.23]), poor sleep quality (OR = 1.12 [1.02, 1.24]), and "high risk" for OSA (OR = 1.15 [1.04, 1.28]). Based upon an interaction analysis, regular physical activity was protective against OSA risk associated with television viewing (P = .04).Excess sitting was associated with relatively poor sleep quality. Sitting while watching television was associated with relatively poor sleep quality and OSA risk and may be an important risk factor for sleep disturbance and apnea risk.
Project description:Sedentary behaviour is an emerging cardiometabolic risk factor in young people. Little is known about how socioeconomic position (SEP) and sedentary behaviour are associated in children and adolescents. This study examines associations between SEP and sedentary behaviour in school-age children and adolescents.The core sample comprised 3822 Health Survey for England 2008 participants aged 5-15 years with complete information on SEP (household income, head of household occupational social class and area deprivation) and self-reported sedentary time (television viewing and other sitting during non-school times). Accelerometer-measured total sedentary time was measured in a subsample (N=587). We examined multivariable associations between SEP (including a composite SEP score) and sedentary time using generalised linear models, adjusting for age, sex, body mass index, physical activity, accelerometer wear time and mutually adjusting for the other SEP indicators.Participants in the highest SEP category spent 16 min/day less (95% CI 6 to 25, p=0.003) watching TV than participants in the lowest SEP category; yet they spent 7 (2 to 16, p=0.010) and 17 (5 to 29, p<0.000) min/day more in non-TV sitting and total (accelerometry-measured) sedentary time, respectively. Associations across individual SEP components varied in strength. Area deprivation was not associated with sedentary time.Low SEP is linked with higher television times but with lower total (accelerometer-measured) sedentary time, and non-TV sitting during non-school time in children and adolescents. Associations between sedentary time and SEP differ by type of sedentary behaviour. TV viewing is not a good proxy for total sedentary time in children.
Project description:To examine the associations between socioeconomic position (SEP) and multidomain self-reported and objectively-assessed sedentary time (ST).Cross-sectional.General population households in England.2289 adults aged 16-96 years who participated in the 2008 Health Survey for England.Accelerometer-measured ST, and self-reported television time, non-television leisure-time sitting and occupational sitting/standing. We examined multivariable associations between household income, social class, education, area deprivation for each SEP indicator (including a 5-point composite SEP score computed by aggregating individual SEP indicators) and each ST indicator using generalised linear models.Accelerometry-measured total ST and occupational sitting/standing were positively associated with SEP score and most of its constituent SEP indicators, while television time was negatively associated with SEP score and education level. Area-level deprivation was largely unrelated to ST. Those in the lowest composite SEP group spent 64 (95% CIs 52 to 76) and 72 (48 to 98), fewer minutes/day in total ST and occupational sitting/standing compared to those in the top SEP group, and an additional 48 (35-60) min/day watching television (p<0.001 for linear trend). Stratified analyses showed that these associations between composite SEP score and total ST were evident only among participants who were in employment.Occupational sitting seems to drive the positive association between SEP and total ST. Lower SEP is linked to higher TV viewing times.
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:High volumes of sitting time are associated with an elevated risk of type 2 diabetes and cardiovascular disease, and with adverse cardiometabolic risk profiles. However, previous studies have predominately evaluated only total sitting or television (TV) viewing time, limiting inferences about the specific cardiometabolic health impacts of sitting accumulated in different contexts. We examined associations of sitting time in four contexts with cardiometabolic risk biomarkers in Australian adults. METHODS:Participants (n?=?3429; mean?±?SD age 58?±?10 years) were adults without clinically diagnosed diabetes or cardiovascular disease from the 2011-2012 Australian Diabetes, Obesity and Lifestyle (AusDiab) study. Multiple linear regressions examined associations of self-reported context-specific sitting time (occupational, transportation, TV-viewing and leisure-time computer use) with a clustered cardiometabolic risk score (CMR) and with individual cardiometabolic risk biomarkers (waist circumference, BMI, resting blood pressure, triglycerides, HDL- and LDL-cholesterol, and fasting and 2-h post-load plasma glucose). RESULTS:Higher CMR was significantly associated with greater TV-viewing and computer sitting time (b [95%CI]?=?0.07 [0.04, 0.09] and 0.06 [0.03, 0.09]), and tended to be associated with higher occupational and transport sitting time (0.01 [-?0.01, 0.03] and 0.03 [-?0.00, 0.06]), after adjustment for potential confounders. Furthermore, keeping total sitting time constant, accruing sitting via TV-viewing and computer use was associated with significantly higher CMR (0.05 [0.02, 0.08] and 0.04 [0.01, 0.06]), accruing sitting in an occupational context was associated with significantly lower CMR (-?0.03 [-?0.05, -?0.01]), while no significant association was seen for transport sitting (0.00 [-?0.03, 0.04]). Results varied somewhat between the respective biomarkers; however, higher sitting time in each domain tended to be associated detrimentally with individual biomarkers except for fasting glucose (non-significant associations) and systolic blood pressure (a beneficial association was observed). Overall, associations were stronger for TV-viewing and computer use, and weaker for occupational sitting. CONCLUSIONS:Higher context-specific sitting times tended to be detrimentally associated, albeit modestly, with CMR and several cardiometabolic risk biomarkers. There was some evidence suggesting that the context in which people sit is relevant above and beyond total sitting time. Methodological issues notwithstanding, these findings may assist in identifying priorities for sitting-reduction initiatives, in order to achieve optimal cardiometabolic health benefits.
Project description: 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:Both short and long durations of sleep are associated with higher mortality, but little is known about the interrelationship between sleep and other modifiable factors in relation to mortality. In the National Institutes of Health-AARP Diet and Health Study (1995-1996), we examined associations between sleep duration and total, cardiovascular disease (CVD), and cancer mortality among 239,896 US men and women aged 51-72 years who were free of cancer, CVD, and respiratory disease. We evaluated the influence of moderate-to-vigorous physical activity, television viewing, and body mass index (BMI; weight (kg)/height (m)(2)) on the sleep-mortality association and assessed their combined association with mortality. During an average of 14 years of follow-up, we identified 44,100 deaths. Compared with 7-8 hours of sleep per day, both shorter and longer sleep durations were associated with higher total and CVD mortality. We found a greater elevation in CVD mortality associated with shorter sleep among overweight and obese people, suggesting a synergistic interaction between sleep and BMI. People in the unhealthy categories of all 4 risk factors (sleep <7 hours/day, moderate-to-vigorous physical activity ?1 hour/week, television viewing ?3 hours/day, and BMI ?25) had significantly higher all-cause (relative risk (RR) = 1.42, 95% confidence interval (CI): 1.34, 1.52), CVD (RR = 1.90, 95% CI: 1.67, 2.17), and cancer (RR = 1.21, 95% CI: 1.09, 1.34) mortality. Short sleep duration may predict higher mortality, particularly CVD mortality, among overweight and obese people.
Project description:A well-known demographic finding in modern society is the inverse association between socioeconomic status and mortality. The purpose of the study was to examine socioeconomic indicators, such as occupational category (white-collar vs blue -collar) and occupational position (managerial vs non-managerial) as determinants of all -cause, cardiovascular disease (CVD) and cancer mortality in a Japanese working population.This is a prospective study.Data of a baseline survey were collected between 1992 and 1995, and ultimately 6929 Japanese workers aged 65 years and younger (3333 men and 3596 women) from 12 rural communities across Japan were followed until the end of 2005.The HRs of death and 95% CIs from all causes were calculated using the Cox proportional hazard model.Men in blue-collar jobs showed an increased all-cause mortality risk compared with those in white-collar jobs (HR 1.64, 95% CI 1.10 to 2.45). Stratified by occupational category, non-managerial women in blue-collar jobs showed a decreased CVD mortality risk compared with managerial women (HR 0.15, 95% CI 0.03 to 0.81), after adjusting for confounding factors. However, non-managerial women in white-collar jobs showed an increased mortality risk compared with managerial women, although this was not significant (HR 2.34, 95% CI 0.25 to 21.87).Socioeconomic disparity according to occupational category was related to the risk of all-cause mortality among Japanese men. There is a potential interaction of occupational category and position in CVD mortality among Japanese women.