Joint effects of objectively-measured sedentary time and physical activity on all-cause mortality

ObjectiveExamine the joint effects of objectively-measured sedentary time and moderate-to-vigorous physical activity (MVPA) on all-cause mortality.MethodsThe present study included data from the 2003–2006 National Health & Nutrition Examination Survey, with mortality follow-up data (via National Death Index) through 2011 (N = 5575 U.S. adults). Sedentary time (activity counts/min between 0 and 99) and MVPA (activity counts/min ≥ 2020) were objectively measured using the ActiGraph 7164 accelerometer.ResultsThe median age of the participants was 50 yrs; proportion of men was 50.2%; proportion of whites was 53.8%, 18.7% for blacks; median follow-up was 81 months; and 511 deaths occurred over the follow-up period. After adjusting for age, gender, race-ethnicity, cotinine, weight status, poverty level, C-reactive protein and comorbid illness (summed score of 0–8 chronic diseases), and for a 1 min increase in MVPA and sedentary time, both MVPA (HR_adjusted = 0.98; 95% CI: 0.96–0.99; P = 0.04) and sedentary time (HR_adjusted = 1.001; 95% CI: 1.0003–1.002; P = 0.008) were independently associated with all-cause mortality. Further, MVPA was associated with all-cause mortality among those with greater (above median) sedentary time (HR_adjusted = 0.95; 95% CI: 0.93–0.97; P < .001). Sedentary time was not associated with all-cause mortality among those engaging in above median levels of MVPA (HR_adjusted = 0.998; 95% CI: 0.996–1.001; P = .32), but sedentary time was associated with increased mortality risk among those below median levels of MVPA (HR = 1.002; 95% CI: 1.001–1.003; P < 0.001).ConclusionsSedentary time and MVPA are independently associated with all-cause mortality. Above median sedentary time levels did not negate the beneficial effects of MVPA on all-cause mortality risk.     

Lack of private health insurance is associated with higher mortality from cancer and other chronic diseases,poor diet quality,and inflammatory biomarkers in the United States

ObjectiveThe lack of health insurance reduces access to care and often results in poorer health outcomes. The present study simultaneously assessed the effects of health insurance on cancer and chronic disease mortality, as well as the inter-relationships with diet, obesity, smoking, and inflammatory biomarkers. We hypothesized that public/no insurance versus private insurance would result in increased cancer/chronic disease mortality due to the increased prevalence of inflammation-related lifestyle factors in the underinsured population.MethodsData from the Third National Health and Nutrition Examination Survey participants (NHANES III;1988–1994) were prospectively examined to assess the effects of public/no insurance versus private insurance and inflammation-related lifestyle factors on mortality risk from cancer, all causes, cardiovascular disease (CVD) and diabetes. Cox proportional hazards regression was performed to assess these relationships.ResultsMultivariate regression analyses revealed substantially greater risks of mortality ranging from 35% to 245% for public/no insurance versus private insurance for cancer (HR = 1.35; 95% CI = 1.09,1.66), all causes (HR = 1.54; 95% CI = 1.39,1.70), CVD (HR = 1.62; 95% CI = 1.38,1.90) and diabetes (HR = 2.45; 95% CI = 1.45,4.14). Elevated CRP, smoking, reduced diet quality and higher BMI were more prevalent in those with public insurance, and were also associated with increased risks of cancer/chronic disease mortality.DiscussionInsurance status was strongly associated with cancer/chronic disease mortality after adjusting for lifestyle factors. The results suggest that inadequate health insurance coverage results in a substantially greater need for preventive strategies that focus on tobacco control, obesity, and improved dietary quality. These efforts should be incorporated into comprehensive insurance coverage programs for all Americans.     

Annual influenza vaccination reduces total hospitalization in patients with chronic hepatitis B virus infection: A population-based analysis

BackgroundThis study evaluated hospitalization and mortality in patients with chronic hepatitis B virus infection (HBV (+)) and matched comparison patients after stratifying the patients according to annual influenza vaccination (Vaccine (+)).MethodsData from Taiwan's National Health Insurance program from 2000 to 2009 were used to identify HBV(+)/vaccine(+) (n = 4434), HBV(+)/Vaccine(−) (n = 3646), HBV(−)/Vaccine(+) (n = 8868), and HBV(−)/Vaccine(−) (n = 8868) cohorts. The risk of pneumonia/influenza, respiratory failure, intensive care, hospitalization, and mortality in the four cohorts was evaluated.ResultsThe total hospitalization rate was significantly lower in patients with chronic HBV infection who received an annual influenza vaccination than in chronic HBV-infected patients who did not receive an influenza vaccination (16.29 vs. 24.02 per 100 person-years), contributing to an adjusted hazard ratio (HR) of 0.56 (95% confidence interval (CI) = 0.50–0.62). The HBV(+)/Vaccine(+) cohort also had lower risks than the HBV(+)/Vaccine(−) cohort for pneumonia and influenza (adjusted HR = 0.79, 95% CI = 0.67–0.92), intensive care unit admission (adjusted HR = 0.33, 95% CI = 0.25–0.43), and mortality (adjusted HR = 0.19, 95% CI = 0.15–0.24).ConclusionsOur results suggest that annual influenza vaccination can reduce the risk of hospitalization and mortality in patients with chronic HBV infection.     

Smoking and mortality among persons aged 75–94

ObjectivesExamine the effect of current level of smoking and lifetime tobacco consumption on mortality in persons 75–94 years of age.MethodsData were from a representative sample of older Jewish persons in Israel, which included 1,200 self-respondent participants aged 75–94 (Mean = 83.1, SD = 5.3) from the Cross-Sectional and Longitudinal Aging Study (CALAS). Data collection took place during 1989–1992. Mortality data on 95.1% of the sample at 20-year follow up were recorded from the Israeli National Population Registry.ResultsThe following variables adversely affected mortality for the whole sample: Smoking 11–20 cigarettes daily (HR = 1.276, p < .05), smoking over 20 cigarettes daily (HR = 1.328, p < .05), total tobacco consumption (HR = 1.002, p < .01), and heavy lifetime tobacco consumption (HR = 1.270, p < .01). Results were similar for persons aged 75–84, but the effect of smoking seems to decrease or disappear for ages 85 and above.ConclusionThis is the first report of all-cause mortality risk in both genders of a representative population aged 75 and over. Increased mortality risk is related to high daily quantity of current smoking, and to cumulative amount of lifetime smoking. The effect of smoking may disappear for ages 85 and above, and should be studied in larger oldest–old samples.     

Disability,more than multimorbidity,was predictive of mortality among older persons aged 80 years and older

ObjectiveIn this study, we evaluate the impact of disability and multimorbidity on the risk of all-cause death in a population of frail older persons living in community.Study Design and SettingWe analyzed data from the Aging and Longevity Study in the Sirente geographic area, a prospective cohort study that collected data on all subjects aged 80 years and older (n = 364). The main outcome measure was all-cause mortality over 4-year follow-up.ResultsA total of 150 deaths occurred. Sixty-seven subjects (44.6%) died in the nondisabled group compared with 83 subjects (55.3%) in the disabled group (P < 0.01). Thirty-nine subjects (31.7%) died among subjects without multimorbidity compared with 111 subjects (46.0%) with two or more diseases (P < 0.01). When examining the combined effect of multimorbidity and disability, the effect of disability on the risk of death was higher than that of multimorbidity. After adjusting for potential confounders, relative to those without disability and multimorbidity, disabled subjects showed an increased risk of death when multimorbidity was associated (hazard ratio [HR] = 3.91; 95% confidence interval [CI] = 1.53–10.00) and in absence of multimorbidity (HR = 2.36; 95% CI = 0.63–8.83).ConclusionOur results show that disability exerts an important influence on mortality, independently of age and other clinical and functional variables.     

Accelerometer determined sedentary behavior and dietary quality among US adults

ObjectiveScant evidence exists pertaining to objectively measured sedentary time and dietary quality among adults. Therefore, we examined the relationships between sedentary time, physical activity, and dietary quality.MethodsCross-sectional analyses of a 4,910 US adults from two cycles (2003–2006) of the National Health and Nutrition Examination Survey. The primary independent variables were sedentary time and physical activity (continuous and categorical), while the outcomes were overall dietary quality (Healthy Eating Index (HEI) 2010), fruit and vegetable scores, and empty caloric intake (kcal).ResultsMultivariable analyses revealed that a 1 min increase in daily sedentary behavior was associated with a 0.2 kcal decrease in empty calories (− 0.18, 95% CI = − 0.34, − 0.03); however, sedentary time was not significantly related to overall dietary quality (HEI) and fruit and vegetable intake. In comparison, a 1 min increase in daily moderate-to-vigorous intensity physical activity was related to a 0.1 higher HEI score (0.08, 95% CI = 0.04, 0.11), a 0.01 higher fruit score (0.01, 95% CI = 0.01, 0.02), and conversely a 1.3 kcal decrease in empty calories (− 1.35, 95% CI = − 2.01, − 0.69). In addition, meeting physical activity guidelines was associated with a 2.8 point higher HEI score (2.82, 95% CI = 1.40, 4.25), a 0.5 point higher fruit score (0.51, 95% CI = 0.31–0.71), and 37.4 fewer empty calories (− 37.43, 95% CI = − 64.86, − 9.10).ConclusionsPhysical activity is significantly related to better overall dietary quality, while sedentary behavior is not. Findings suggest the need to promote physical activity and encourage adherence to dietary guidelines jointly, whereas sedentary behavior and overall dietary quality might need to be targeted independently.     

Re-evaluating the volume–outcome relationship in hemodialysis patients

ObjectivesWe sought to determine whether dialysis patient mortality rates are associated with differences in dialysis facility size, and whether this relationship differs among higher risk diabetic and lower-risk non-diabetic patients.MethodsUsing 186,554 adult end-stage renal disease patients initiating hemodialysis at standalone facilities in the United States between 1996 and 1999, we evaluated relationships between dialysis facility size and survival to 5 years. We performed separate analyses for patients with and without diabetes as their primary cause of end-stage renal disease. Facility size was defined according to the number of hemodialysis patients at year's end (small ≤60, medium 61–120, and large ≥120).ResultsIncreasing facility size was associated with a reduced risk of mortality at 4 years for both diabetic (HR = 0.983 per 10 unit increase, 95% CI = 0.967, 0.999) and non-diabetic patients (HR 0.977 per 10 unit increase, 95% CI = 0.963, 0.992) dialyzing in small facilities, and for diabetic patients (HR 0.989 per 10 unit increase, 95% CI = 0.980, 0.998) dialyzing in medium size facilities.ConclusionsSmaller facility size is associated with increasing long-term mortality for in-center hemodialysis patients. This relationship appears to be more pronounced among higher-risk diabetic vs. lower-risk non-diabetic patients.     

Implementing classroom physical activity breaks: Associations with student physical activity and classroom behavior

ObjectiveTo investigate the relation of classroom physical activity breaks to students' physical activity and classroom behavior.MethodsSix elementary-school districts in California implemented classroom physical activity interventions in 2013–2014. Students' (N = 1322) accelerometer-measured moderate-to-vigorous physical activity (MVPA) during school and teachers' (N = 397) reports of implementation and classroom behavior were assessed in 24 schools at two time points (both post-intervention). Mixed-effects models accounted for nested data.ResultsMinutes/day of activity breaks was positively associated with students' MVPA (βs = .07–.14; ps = .012–.016). Students in classrooms with activity breaks were more likely to obtain 30 min/day of MVPA during school (OR = 1.75; p = .002). Implementation was negatively associated with students having a lack of effort in class (β = − .17; p = .042), and student MVPA was negatively associated with students being off task or inattentive in the classroom (β = − .17; p = .042). Students provided with 3–4 physical activity opportunities (classroom breaks, recess, PE, dedicated PE teacher) had ≈ 5 more min/day of school MVPA than students with no opportunities (B = 1.53 min/opportunity; p = .002).ConclusionsImplementing classroom physical activity breaks can improve student physical activity during school and behavior in the classroom. Comprehensive school physical activity programs that include classroom-based activity are likely needed to meet the 30 min/day school physical activity guideline.     

Objectively measured sedentary time and associations with insulin sensitivity: Importance of reallocating sedentary time to physical activity

ObjectiveThe aim of this study is to quantify associations between objectively measured sedentary time and markers of insulin sensitivity by considering allocation into light-intensity physical activity or moderate- to vigorous-intensity physical activity (MVPA).MethodsParticipants with an increased risk of impaired glucose regulation (IGR) were recruited (Leicestershire, United Kingdom, 2010–2011). Sedentary, light-intensity physical activity and MVPA time were measured using accelerometers. Fasting and 2-hour post-challenge insulin and glucose were assessed; insulin sensitivity was calculated by HOMA-IS and Matsuda-ISI. Isotemporal substitution regression models were used. Data were analysed in 2014.Results508 participants were included (average age = 65 years, female = 34%). Reallocating 30 min of sedentary time into light-intensity physical activity was associated a 5% (95% CI 1, 9%; p = 0.024) difference in Matsuda-ISI after adjustment for measured confounding variables. Reallocation into MVPA was associated with a 15% (7, 25%; p < 0.001) difference in HOMA-IS and 18% (8, 28%; p < 0.001) difference in Matsuda-ISI. Results for light-intensity physical activity were modified by IGR status with stronger associations seen in those with IGR.ConclusionsReallocating sedentary time into light-intensity physical activity or MVPA was associated with differences in insulin sensitivity, with stronger and more consistent associations seen for MVPA.     

Anxiety predicted premature all-cause and cardiovascular death in a 10-year follow-up of middle-aged women

ObjectiveResearch on emotional distress and mortality has largely focused on depression in men and in elderly populations. We examined the relation between anxiety and mortality in women at midlife, adjusting for depression.Study Design and SettingAt baseline, 5,073 healthy Dutch women aged 46–54 years (mean = 50.4 ± 2.1) and living in Eindhoven, completed a three-item anxiety scale (“being anxious/worried,” “feeling scared/panicky,” “ruminating about things that went wrong;” Cronbach's α = 0.77). The primary outcome was all-cause mortality at 10-year follow-up; secondary outcomes were cardiovascular and lung/breast cancer death.ResultsAt follow-up, 114 (2.2%) women had died at the mean age of 56.4 ± 3.1 years. Lung cancer (23%), cardiovascular disease (18%), and breast cancer (15%) were the major causes of death. Smoking, living alone, and lower education were related to mortality, but depression was not. Adjusting for these variables, anxiety was associated with a 77% increase in mortality risk (hazard ratio [HR] = 1.77, 95% confidence interval [CI]: 1.14–2.74, P = 0.011). Anxiety was related to cardiovascular death (HR = 2.77, 95% CI: 1.17–6.58, P = 0.021); there was also a trend for lung cancer death (HR = 1.91, 95% CI: 0.90–4.06, P = 0.095) but not for breast cancer death.ConclusionAnxiety predicted premature all-cause and cardiovascular death in middle-aged women, after adjustment for standard risk factors and depression.     

Daily movement patterns and predicted 10-yr risk for a first atherosclerotic cardiovascular disease (ASCVD) event using the pooled cohort risk equations among US adults

ObjectiveExamine the association between movement patterns and predicted risk of a first atherosclerotic cardiovascular disease (ASCVD) event.MethodsData from the 2003–2006 National Health and Nutrition Examination Survey (NHANES) were used (40–79 yrs; N = 2421). Participants wore an ActiGraph 7164 accelerometer to create four movement pattern groups; Group 1: ≥ 150 min/wk of moderate-to-vigorous physical activity (MVPA) and light-intensity physical activity (LIPA) ≥ sedentary behavior (SB); Group 2: ≥ 150 min/wk of MVPA and LIPA < SB; Group 3: < 150 min/wk of MVPA and LIPA ≥ SED; and Group 4: < 150 min/wk of MVPA and LIPA < SB. 10-yr risk for a first ASCVD event was estimated using the pooled cohort equations.ResultsAfter adjusting for age, gender, race–ethnicity and obesity, Group 2 (β = − 0.28; p = 0.44) was not significantly different than Group 1, but Groups 3 (β = 1.09; p = 0.01) and 4 (β = 1.44; p < 0.001) had a higher pooled risk score.ConclusionsThose in the least desirable movement pattern (Group 4) had the highest pooled risk score. Given the similar risk scores for Groups 1 and 2, future research is needed to determine if sufficient MVPA can counteract the potential consequences associated with an imbalanced LIPA:SB ratio (i.e., LIPA < SB).     

Association between compliance with physical activity guidelines,sedentary behavior and depressive symptoms

Physical inactivity, i.e. not engaging in adequate moderate-to-vigorous physical activity (MVPA), has been identified as a risk factor for depression. Increased sedentary time has further been identified as a potential risk factor for depression. We analyzed NHANES 2005–2006 data to examine the associations between compliance with physical activity guidelines (PAG) and sedentary time with depression. We utilized accelerometer data to assess compliance with PAG and sedentary time, and we used the Patient Health Questionnaire (PHQ-9) to assess presence of depression. Participants were classified as compliant with PAG or non-compliant based on MVPA accumulated in bouts of 10 min or more. We further divided these two groups into quartiles of sedentary time. We conducted logistic regression analyses to test for the interaction effect of PAG compliance and sedentary behavior on depression. Analyses were conducted in 2014–2015 at the University of Illinois at Urbana-Champaign. Mean depression score among compliant participants was 1.65 (SD = 2.61), whereas it was higher among the non-compliant participants (mean = 2.52, SD = 3.51). Logistic regression indicated a statistically significant interaction effect between MVPA and sedentary time on depression scores. There was no apparent trend in depression scores across quartiles of sedentary time in the compliant group. However, adjusted odds ratios for depression increased with increasing sedentary time among the non-compliant group. We provide evidence that compliance with PAG is associated with reduced depressive symptoms regardless of sedentary behavior; however, increased sedentary behavior may increase the risk of depression among those who are not physically active at a level which meets national guidelines.     

Physically active vs. sedentary academic lessons: A dose response study for elementary student time on task

BackgroundPhysically active academic lessons are an effective intervention to reduce sedentary time and increase student physical activity. They have also been shown to enhance task engagement, as indicated by observations of attention and behavior control, time on task (TOT). However, it is not clear if the improved TOT stems from the physical activity or if it is the result of an enjoyable break from traditional instruction. If it is due to physical activity, what dose of intensity is required for the effect? This study was designed to test these questions.MethodsParticipants were 320 children (7–9 years) recruited from school districts in Central Texas in 2012. They were assigned by classroom (n = 20) to one of four conditions: 1) sedentary, standard lesson (n = 72); 2) sedentary academic game (n = 87); 3) low to moderate intensity PA (LMPA), academic game (n = 81); and 4) moderate to vigorous intensity PA (MVPA), academic game (n = 76). Measures included PA via accelerometer and TOT.ResultsMixed-method RMANOVA indicated TOT decreased following the standard lesson (p < 0.001), showed no change following the sedentary academic game (p = 0.68), and increased following the LMPA (p < 0.01) and MVPA (p < 0.001) academic games.ConclusionsWhile the sedentary, academic game prevented the reduction in TOT observed in the standard lesson, PA resulted in increased TOT. Future research should be designed to examine the potential academic benefits of the change in TOT.     

Six-month outcome of elderly people hospitalized via the emergency department: the SAFES cohort

BackgroundThe objective of the study was to identify factors predictive of 6-month institutionalization or mortality in frail elderly patients after acute hospitalization.MethodsA prospective cohort of elderly subjects 75 years and older was set up in nine French teaching hospitals. Data obtained from a comprehensive geriatric assessment were used in a Cox model to predict 6-month institutionalization or mortality. Institutionalization was defined as incident admission either to a nursing home or other long-term care facility during the follow-up period.ResultsCrude institutionalization and death rates after 6 months of follow-up were 18% and 24%, respectively. Independent predictors of institutionalization were: living alone (HR = 1.83; 95% CI = 1.27–2.62) or a higher number of children (HR = 0.86; 95% CI = 0.78–0.96), balance problems (HR = 1.72; 95% CI = 1.19–2.47), malnutrition or risk thereof (HR = 1.93; 95% CI = 1.24–3.01), and dementia syndrome (HR = 1.88; 95% CI = 1.32–2.67). Factors found to be independently related to 6-month mortality were exclusively medical factors: malnutrition or risk thereof (HR = 1.92; 95% CI = 1.17–3.16), delirium (HR = 1.80; 95% CI = 1.24–2.62), and a high level of comorbidity (HR = 1.62; 95% CI = 1.09–2.40). Institutionalization (HR = 1.92; 95% CI = 1.37–2.71) and unplanned readmission (HR = 4.47; 95% CI = 3.16–2.71) within the follow-up period were also found as independent predictors.ConclusionThe main factors predictive of 6-month outcome identified in this study are modifiable by global and multidisciplinary interventions. Their early identification and management would make it possible to modify frail elderly subjects’ prognosis favorably.     

Empowering adolescents to be physically active: Three-year results of the Sigue la Huella intervention

ObjectiveTo examine the effects of a school-based intervention called Sigue la Huella (Follow the Footstep) on adolescents' daily moderate-to-vigorous physical activity (MVPA).MethodThis quasi-experimental, cohort study took place in four secondary schools in Huesca (Spain) during the 2009–2010, 2010–2011, and 2011–2012 academic years (students aged 12–15 years). Two schools were assigned to the experimental condition (n = 368) and two schools to the control condition (n = 314). Sigue la Huella was based on the social ecological model and self-determination theory. MVPA was measured for 7 days on 4 occasions using accelerometers. Data were analyzed with individual growth curve models.ResultsThere was a significant difference in linear growth rate of daily MVPA between the experimental and the control group, independent of study wave, type of school (public vs. private), grade level and gender (p < 0.001). Specifically, MVPA increased in the experimental group (β = 7.02, 95% confidence interval (CI) = 1.27 to 12.78, p = 0.017) and tended to decrease in the control group (β = − 5.26, 95% CI = − 11.17 to 0.65, p < 0.081). The observed increase was larger in boys than in girls (p = 0.003).ConclusionsSigue la Huella had a positive effect on adolescents' daily MVPA over three school years. Both genders benefited from the intervention, although boys to a greater extent.     

The 23-valent pneumococcal polysaccharide vaccine is effective in elderly adults over 75 years old—Taiwan's PPV vaccination program

BackgroundPneumococcal infection is a serious cause of mortality and morbidity in the elderly. A nationwide pneumococcal polysaccharide vaccine (PPV) program for elderly adults aged 75 years and older was conducted in Taiwan in 2008. The efficacy of the PPV in this very elderly population was evaluated.MethodsThe data were analyzed using the Taiwan National Health Insurance Research Database (NHIRD), the cause-of-death registration database and the invasive pneumococcal disease (IPD) notification database of Taiwan's Ministry of Health and Welfare. The efficacy of PPV administration in this very elderly population was evaluated using multivariate logistic regression after propensity score matching (PSM). The rates of IPD, death from IPD, pneumonia hospitalization, death from pneumonia, and all-cause mortality were compared for those who did and did not receive the PPV.ResultsAmong the 1078,955 eligible people, 318,257 (29.5%) received the PPV, and 760,698 (70.5%) were not vaccinated. Using PSM to adjust for confounding factors, including age, gender, influenza vaccination status, associated chronic diseases and health care utilization, those who received the PPV had significantly lower odds ratios (ORs) for IPD (OR = 0.24, 95% CI = 0.123–0.461, p < 0.001), death from IPD (OR = 0.09, 95% CI = 0.011–0.704, p < 0.022, p < 0.001), pneumonia hospitalization (OR = 0.40, 95% CI = 0.395–0.415, p < 0.001), death from pneumonia (OR = 0.07, 95% CI = 0.059–0.082, p < 0.001), and all-cause mortality (OR = 0.07, 95% CI = 0.069–0.072, p < 0.001) compared with those who were not vaccinated.ConclusionsPPV vaccination in the previous year was associated with a 60% reduction in pneumonia hospitalization, a 76% reduction in IPD, and a greater than 90% reduction in death from pneumonia, IPD and all causes among people over 75 years old in Taiwan. Data from subsequent years in Taiwan and similar populations elsewhere are needed to evaluate the contribution of underlying variations in the mortality rate and the confounding effects of prior disease severity to these findings.     

Sedentary Behavior,Physical Activity,and All-Cause Mortality: Dose-Response and Intensity Weighted Time-Use Meta-analysis

ObjectivesPrevious studies have placed those with excessive sedentary behavior at increased risk of all-cause mortality. There is evidence of interdependency of sedentary behavior with physical activity, and its elucidation will have implications for guidelines and practice. This study investigated if sedentary behavior–related mortality risk can be offset by moderate- to vigorous-intensity physical activity (MVPA) considered in a time-use fashion.DesignPubMed was searched (from its inception till May 2018) for studies or meta-analyses that used data harmonized for MVPA. Of the 17 data-custodians located, 7 provided data on sitting time or TV viewing time, or both. A dose-response meta-analysis modeling log relative risks of all-cause mortality against uncompensated sedentary behavior metabolic equivalent hours (USMh) was run using the robust error meta-regression method. (Registration: CRD42017062439)SettingIndividual subject data held by data custodians on this topic.ParticipantsGeneral adults.MeasurementsSedentary time, MVPA.ResultsFive harmonized cohorts of sitting time (258,688 participants) and 4 of TV viewing time (156,593 participants) demonstrated that sedentary behavior was significantly associated with mortality, but this risk was attenuated with increasing energy expenditure through MVPA modeled in a time-use fashion. The average increment in mortality per USMh spent on sitting was 1% [relative risk (RR) 1.01, 95% confidence interval (CI) 1.00, 1.02; P = .01] and that per USMh spent on TV viewing was 7% (RR 1.07, 95% CI 1.04, 1.10; P < .001). The thresholds for risk started at 7 USMh for sitting and 3 USMh for TV viewing.Conclusions/ImplicationsOur findings suggest that overall daily sitting time energy expenditure of 7 MET-hours (or TV viewing of 3 MET-hours) in excess of that expended on MVPA is independently related to all-cause mortality. These findings support the view that sitting is strongly influenced by consideration of concurrent MVPA in its impact on adverse health consequences and that the USMh is a more practical metric of sedentary behavior.     

Objectively measured physical activity,sedentary time and subclinical vascular disease: Cross-sectional study in older British men

Low physical activity (PA) and high levels of sedentary time (ST) are associated with higher cardiovascular disease (CVD) risk among older people. However, their independent contribution and importance of duration of PA and ST bouts remain unclear. We investigated associations between objectively measured PA, ST and non-invasive vascular measures, markers of CVD risk.Cross-sectional study of 1216 men from the British Regional Heart Study, mean age 78.5 years, measured in 2010–2012. Carotid intima thickness (CIMT), distensibility coefficient (DC) and plaque presence were measured using ultrasound; pulse wave velocity (cfPWV) and augmentation index (AIx) using a Vicorder. PA and ST were measured using hip-worn ActiGraph GT3X accelerometers.After adjusting for covariates, each additional 1000 steps per day was associated with a 0.038 m/s lower cfPWV (95% CI = − 0.076, 0.0003), 0.095 10^− 3 kPa^− 1 higher DC (95% CI = 0.006, 0.185), 0.26% lower AIx (95% CI = − 0.40, − 0.12) and a 0.005 mm lower CIMT (95% CI = − 0.008, − 0.001). Moderate and vigorous PA (MVPA) was associated with lower AIx and CIMT, light PA (LPA) with lower cfPWV and CIMT and ST with higher cfPWV, AIx and CIMT and lower DC. LPA and ST were highly correlated (r = − 0.62). The independence of MVPA and ST or MVPA and LPA was inconsistent across vascular measures. Bout lengths for both PA and ST were not associated with vascular measures.In our cross-sectional study of older men, all PA regardless of intensity or bout duration was beneficially associated with vascular measures, as was lower ST. LPA was particularly relevant for cfPWV and CIMT.     

Dose–response association of moderate-to-vigorous physical activity with cardiovascular biomarkers and all-cause mortality: Considerations by individual sports,exercise and recreational physical activities

BackgroundPrevious research demonstrates that moderate-to-vigorous physical activity (MVPA) is associated with reduced all-cause mortality risk. Our understanding of whether individual physical activities are associated with all-cause mortality is less understood.MethodsData from the 1999–2006 NHANES were employed, with follow-up through 2011. 48 different individual physical activities (e.g., swimming, running, bicycling) were assessed, and total MVPA MET-min-month was calculated based on their responses to these 48 individual physical activities.ResultsGreater engagement in MVPA was associated with more favorable cardiovascular biomarkers, particularly for men. Even after adjustment for total MVPA, different individual physical activities were associated with cardiovascular biomarkers across gender. When compared to those not meeting guidelines (0–1999 MVPA MET-min-month), a dose–response association between MVPA and mortality was observed, with those engaging in 5 times the guideline level having the lowest risk of all-cause mortality (45% reduced risk). There was no evidence of a harmful effect of very high MVPA (e.g., 20,000 + MVPA MET-min-month).ConclusionsEngaging in MVPA even below the minimum recommendation was associated with survival benefits, and the greatest survival effects occurred at a dose of approximately 5 times the minimum recommendation. Although very high levels (e.g., 10 times the minimum recommendation) of self-reported MVPA did not demonstrate the greatest survival effects, high levels of physical activity did not appear to have harmful effects.     

Dose–response association of physical activity with HbA1c: Intensity and bout length

ObjectiveThe aims of this study were to characterize the dose–response relationship between moderate-to-vigorous intensity physical activity (MVPA), and light-intensity activity with HbA1c in adults at low, moderate, and high risks of type 2 diabetes, and to compare the relationship of short (1 to 9 min) versus long (10 + min) bouts of MVPA with HbA1c.MethodsData from 2707 participants from the 2003–2006 National Health And Nutrition Examination Survey were analyzed in 2014–2015. Type 2 diabetes risk was classified into three groups based upon age (< 40 years; ≥ 40 years) and BMI (< 30; ≥ 30). The relationship between HbA1c and accelerometer-based physical activity variables was assessed using multiple regression models.ResultsThere was a curvilinear dose–response relationship between HbA1c with total activity and MVPA in adults at moderate or high risk for type 2 diabetes: higher amounts of physical activity were associated with lower HbA1c. The association of physical activity on HbA1c was stronger at lower levels of physical activity. There was no dose–response relationship in adults at low risk for type 2 diabetes. The relationship between short bouts with HbA1c was stronger than for bouts ≥ 10 min.ConclusionsIn adults at risk for type 2 diabetes, there is a dose–response relationship between physical activity and HbA1c levels such that the relationship: (1) is curvilinear; (2) is stronger when a higher percent of total activity comes from MVPA; and (3) is more potent with short bouts of MVPA. Fractionalized physical activity of at least moderate-intensity may contribute to long-term glucose control.