Impact of radiologically stratified exacerbations: insights into pneumonia aetiology in COPD.

BACKGROUND: COPD patients have increased risk of developing pneumonia, which is associated with poor outcomes. It can be symptomatically indistinguishable from exacerbations, making diagnosis challenging. Studies of pneumonia in COPD have focused on hospitalised patients and are not representative of the ambulant COPD population. Therefore, we sought to determine the incidence and aetiology of acute exacerbation events with evidence of pneumonic radiographic infiltrates in an outpatient COPD cohort. METHODS: One hundred twenty-seven patients with moderate to very severe COPD aged 42-85 years underwent blood and sputum sampling over one year, at monthly stable visits and within 72 h of exacerbation symptom onset. 343 exacerbations with chest radiographs were included. RESULTS: 20.1% of exacerbations had pneumonic infiltrates. Presence of infiltrate was highly seasonal (Winter vs summer OR 3.056, p = 0.027). In paired analyses these exacerbation events had greater increases in systemic inflammation. Bacterial detection rate was higher in the pneumonic group, with Haemophilus influenzae the most common bacteria in both radiological groups. Viral detection and sputum microbiota did not differ with chest radiograph appearance. CONCLUSIONS: In an outpatient COPD cohort, pneumonic infiltrates at exacerbation were common, and associated with more intense inflammation. Bacterial pathogen detection and lung microbiota were not distinct, suggesting that exacerbations and pneumonia in COPD share common infectious triggers and represent a continuum of severity rather than distinct aetiological events. TRIAL REGISTRATION: Trial registration Number: NCT01360398 .

Impact and associations of eosinophilic inflammation in COPD: analysis of the AERIS cohort.

Eosinophilic inflammation in chronic obstructive pulmonary disease (COPD) predicts response to treatment, especially corticosteroids. We studied the nature of eosinophilic inflammation in COPD prospectively to examine the stability of this phenotype and its dynamics across exacerbations, and its associations with clinical phenotype, exacerbations and infection.127 patients aged 40-85 years with moderate to very severe COPD underwent repeated blood and sputum sampling at stable visits and within 72 h of exacerbation for 1 year.Blood eosinophils ≥2% was prevalent at baseline, and predicted both predominantly raised stable-state eosinophils across the year (area under the curve 0.841, 95% CI 0.755-0.928) and increased risk of eosinophilic inflammation at exacerbation (OR 9.16; p<0.001). Eosinophils ≥2% at exacerbation and eosinophil predominance at stable visits were associated with a lower risk of bacterial presence at exacerbation (OR 0.49; p=0.049 and OR 0.25; p=0.065, respectively). Bacterial infection at exacerbation was highly seasonal (winter versus summer OR 4.74; p=0.011) in predominantly eosinophilic patients.Eosinophilic inflammation is a common and stable phenotype in COPD. Blood eosinophil counts in the stable state can predict the nature of inflammation at future exacerbations, which when combined with an understanding of seasonal variation provides the basis for the development of new treatment paradigms for this important condition.

Relationship between pulmonary matrix metalloproteinases and quantitative CT markers of small airways disease and emphysema in COPD.

BACKGROUND: Matrix metalloproteinases (MMPs) are proteolytic enzymes that can degrade the extracellular matrix and drive tissue remodelling, key processes in the pathogenesis of COPD. The development of small airway disease has been identified as a critical mechanism in the early development of airflow obstruction but the contribution of MMPs in human disease is poorly characterised. OBJECTIVES: We investigated the role of MMPs and inflammatory cytokines in the lung by quantifying levels and determining relationships with the key pathological components of COPD in patients and healthy controls. METHODS: We analysed levels of MMPs and inflammatory cytokines in bronchoalveolar lavage from 24 COPD and 8 control subjects. Each subject underwent spirometry and high-resolution CT. Image analysis quantitatively assessed emphysema, bronchial wall thickening and small airways disease. RESULTS: Multiple MMPs (MMP-1, -2, -3, -8, -9 and -10) and cytokines (interleukin (IL) 6 and IL-8) were elevated in lungs of subjects with COPD. MMP-3, -7, -8, -9, -10 and -12 concentrations closely associated with CT markers of small airways disease. Emphysema severity was also associated with MMP-3, -7 and -10. However, there were no strong relationships between MMPs and bronchial wall thickness of the larger airways. CONCLUSIONS: Pulmonary MMP concentrations are directly associated with the extent of gas trapping and small airways disease identified on CT scan. This study suggests that MMPs play a significant role in small airways remodelling, a key feature in the pathogenesis of COPD. TRIAL REGISTRATION NUMBER: NCT01701869.

Distinct emphysema subtypes defined by quantitative CT analysis are associated with specific pulmonary matrix metalloproteinases.

BACKGROUND: Emphysema is characterised by distinct pathological sub-types, but little is known about the divergent underlying aetiology. Matrix-metalloproteinases (MMPs) are proteolytic enzymes that can degrade the extracellular matrix and have been identified as potentially important in the development of emphysema. However, the relationship between MMPs and emphysema sub-type is unknown. We investigated the role of MMPs and their inhibitors in the development of emphysema sub-types by quantifying levels and determining relationships with these sub-types in mild-moderate COPD patients and ex/current smokers with preserved lung function. METHODS: Twenty-four mild-moderate COPD and 8 ex/current smokers with preserved lung function underwent high resolution CT and distinct emphysema sub-types were quantified using novel local histogram-based assessment of lung density. We analysed levels of MMPs and tissue inhibitors of MMPs (TIMPs) in bronchoalveolar lavage (BAL) and assessed their relationship with these emphysema sub-types. RESULTS: The most prevalent emphysema subtypes in COPD subjects were mild and moderate centrilobular (CLE) emphysema, while only small amounts of severe centrilobular emphysema, paraseptal emphysema (PSE) and panlobular emphysema (PLE) were present. MMP-3, and -10 associated with all emphysema sub-types other than mild CLE, while MMP-7 and -8 had associations with moderate and severe CLE and PSE. MMP-9 also had associations with moderate CLE and paraseptal emphysema. Mild CLE occurred in substantial quantities irrespective of whether airflow obstruction was present and did not show any associations with MMPs. CONCLUSION: Multiple MMPs are directly associated with emphysema sub-types identified by CT imaging, apart from mild CLE. This suggests that MMPs play a significant role in the tissue destruction seen in the more severe sub-types of emphysema, whereas early emphysematous change may be driven by a different mechanism. TRIAL REGISTRATION: Trial registration number NCT01701869 .

Age- and sex-specific criterion validity of the health survey for England Physical Activity and Sedentary Behavior Assessment Questionnaire as compared with accelerometry.

The criterion validity of the 2008 Physical Activity and Sedentary Behavior Assessment Questionnaire (PASBAQ) was examined in a nationally representative sample of 2,175 persons aged ≥16 years in England using accelerometry. Using accelerometer minutes/day greater than or equal to 200 counts as a criterion, Spearman's correlation coefficient (ρ) for PASBAQ-assessed total activity was 0.30 (95% confidence interval (CI): 0.25, 0.35) in women and 0.20 (95% CI: 0.15, 0.26) in men. Correlations between accelerometer counts/minute of wear time and questionnaire-assessed relative energy expenditure (metabolic equivalent-minutes/day) were higher in women (ρ = 0.41, 95% CI: 0.36, 0.46) than in men (ρ = 0.32, 95% CI: 0.26, 0.38). Similar correlations were observed for minutes/day spent in vigorous activity (women: ρ = 0.39, 95% CI: 0.33, 0.46; men: ρ = 0.31, 95% CI: 0.26, 0.36) and moderate-to-vigorous activity (women: ρ = 0.42, 95% CI: 0.36, 0.48; men: ρ = 0.38, 95% CI: 0.32, 0.45). Correlations for time spent being sedentary (<100 counts/minute) were 0.30 (95% CI: 0.24, 0.35) and 0.25 (95% CI: 0.19, 0.30) in women and men, respectively. Sedentary behavior correlations showed no sex difference. The validity of sedentary behavior and total physical activity was higher in older age groups, but validity was higher in younger persons for vigorous-intensity activity. The PASBAQ is a useful and valid instrument for ranking individuals according to levels of physical activity and sedentary behavior.

Associations between socio-economic position and sedentary behaviour in a large population sample of Australian middle and older-aged adults: The Social, Economic, and Environmental Factor (SEEF) Study.

OBJECTIVE: Socioeconomic position (SEP) is associated with health-related behaviours but little is known about the socioeconomic gradient of sedentary behaviour. This study aims to assess the associations between SEP and multiple indicators of sedentary behaviour among Australian mid-to-older age adults. METHOD: Multivariate analysis of 60,404 (>47years, 26,366 in paid employment) participants in the Social, Economic, and Environmental Factor Study, examining the associations between SEP (educational attainment, household income, and an area-level index of socioeconomic advantage) and self-reported daily time for total sitting, TV viewing, computer use, and car driving. Data was collected in 2010 in New South Wales, Australia. RESULTS: For participants in paid employment, we found positive associations with all SEP indicators for total sitting and computer use time, and inverse associations for TV viewing. Driving time was inversely associated with education level only. We observed similar but less pronounced patterns of associations among participants not in paid employment. CONCLUSION: Higher SEP is linked to higher total sitting and computer time, particularly among those in paid employment, and lower TV viewing time.

Associations between indicators of screen time and adiposity indices in Portuguese children.

OBJECTIVES: To examine associations between three types of screen time (TV, electronic games (EG), and personal computer (PC)) and two proxies of adiposity (body mass index (BMI) and sum of skinfolds) in children. DESIGN: The sample comprised 17,509 children aged 2-13 years who participated in the 2009/10 Portuguese Prevalence Study of Obesity in Childhood. METHODS: Complex samples generalised linear models, using school as a cluster variable were ran separately for each combination of ST predictor and adiposity-related outcome, adjusting for covariates including age, sex, physical activity, diet, and parental factors. Missing values in predictors and covariates were imputed. RESULTS: Watching TV for >2h/day compared to <1h/day was associated with higher age- and sex-specific BMI standard deviation score (coefficient: 0.06, 95% CI: 0.01 to 0.12, linear trend p=0.008) and sum of skinfolds (logged and back transformed 0.04, 0.02 to 0.07, p=<0.001). We also found weak evidence for an inverse association between PC and BMI. CONCLUSIONS: Associations between ST and adiposity differ by both type of ST and type of adiposity marker. Only TV viewing was consistently associated with adiposity. Studies using a single adiposity marker looking at total screen time or total sedentary behaviour time may miss or confound type-specific associations.

Physical activity education in the undergraduate curricula of all UK medical schools: are tomorrow's doctors equipped to follow clinical guidelines?

Physical activity (PA) is a cornerstone of disease prevention and treatment. There is, however, a considerable disparity between public health policy, clinical guidelines and the delivery of physical activity promotion within the National Health Service in the UK. If this is to be addressed in the battle against non-communicable diseases, it is vital that tomorrow's doctors understand the basic science and health benefits of physical activity. The aim of this study was to assess the provision of physical activity teaching content in the curricula of all medical schools in the UK. Our results, with responses from all UK medical schools, uncovered some alarming findings, showing that there is widespread omission of basic teaching elements, such as the Chief Medical Officer recommendations and guidance on physical activity. There is an urgent need for physical activity teaching to have dedicated time at medical schools, to equip tomorrow's doctors with the basic knowledge, confidence and skills to promote physical activity and follow numerous clinical guidelines that support physical activity promotion.

Seasonality, risk factors and burden of community-acquired pneumonia in COPD patients: a population database study using linked health care records.

BACKGROUND: Community-acquired pneumonia (CAP) is more common in patients with COPD than in the adult general population, with studies of hospitalized CAP patients consistently reporting COPD as a frequent comorbidity. However, despite an increasing recognition of its importance, large studies evaluating the incidence patterns over time, risk factors and burden of CAP in COPD are currently lacking. METHODS: A retrospective observational study using a large UK-based database of linked primary and secondary care records was conducted. Patients with a diagnosis of COPD aged ≥40 years were followed up for 5 years from January 1, 2010. CAP and exacerbation episodes were identified from hospital discharge data and primary care coding records, and rates were calculated per month, adjusting for mortality, and displayed over time. In addition, baseline factors predicting future risk of CAP and hospital admission with CAP were identified. RESULTS: A total of 14,513 COPD patients were identified: 13.4% (n=1,938) had ≥1 CAP episode, of whom 18.8% suffered from recurrent (≥2) CAP. Highest rates of both CAP and exacerbations were seen in winter. A greater proportion of frequent, compared to infrequent, exacerbators experienced recurrent CAP (5.1% versus 2.0%, respectively, P<0.001); 75.6% of CAP episodes were associated with hospital admission compared to 22.1% of exacerbations. Older age and increasing grade of airflow limitation were independently associated with increased odds of CAP and hospital admission with CAP. Other independent predictors of future CAP included lower body mass index, inhaled corticosteroid use, prior frequent exacerbations and comorbidities, including ischemic heart disease and diabetes. CONCLUSION: CAP in COPD demonstrates clear seasonal patterns, with patient characteristics predictive of the odds of future CAP and hospital admission with CAP. Highlighting this burden of COPD-associated CAP during the winter period informs us of the likely triggers and the need for more effective preventive strategies.

Temporal trends in socioeconomic inequalities in obesity prevalence among economically-active working-age adults in Scotland between 1995 and 2011: a population-based repeated cross-sectional study.

OBJECTIVES: Obesity has been an alarming public health issue in the UK. Socioeconomic inequalities in obesity have been well-studied, however limited studies addressed inequality trends over time and none of them in Scotland. METHODS: We used nationally-representative data from the Scottish Health Survey (SHeS) across four time points between 1995 and 2010/2011. Respondents were economically active adults aged 16-65 years (N=27,059, 12,218 men). Socioeconomic position (SEP) was assessed by highest educational qualification, occupational social class and household income (2003 and 2010/2011 only) as well as a composite SEP score. We carried out sex-stratified logistic regression analyses (adjusted for age, smoking status, alcohol consumption, self-rated general health and physical activity) and we computed the relative index of inequality (RII). RESULTS: Between 1995 and 2010/2011, obesity prevalence increased in both men (from 17% in 1995 to 30.2% in 2010/2011, 2010/2011 OR of obesity compared with 1995=2.07; 95% CI 1.83 to 2.34) and women (from 18.4% to 30.2%; OR=1.85; 95% CI 1.66 to 2.07). Increase in obesity prevalence was observed across all socioeconomic strata, within which the most rapid increase was among males from the highest socioeconomic groups. RII showed that educational inequalities in obesity narrowed for both men (p=0.007) and women (p=0.008). Income inequalities in obesity between 2003 and 2010/2011 in women were also reduced (p=0.046) on the relative scale. CONCLUSIONS: Obesity prevalence in Scotland increased substantially between 1995 and 2010/2011, although socioeconomic inequalities have decreased due to the more rapid increase in the higher socioeconomic strata.

Associations between objectively assessed and questionnaire-based sedentary behaviour with BMI-defined obesity among general population children and adolescents living in England.

OBJECTIVES: Sedentary behaviour (SB) is an emerging candidate risk factor for obesity in young people. Evidence to date is conflicting and it is unclear how different SB types are associated with obesity independently of physical activity. The objective of this study was to examine associations between a range of objectively measured and questionnaire-based SB indicators with obesity and body mass index (BMI) to assess whether these associations were independent of physical activity. PARTICIPANTS: 4469 (705 with accelerometer data) children aged 5-15 years from the 2008 Health Survey for England. OUTCOMES: The outcome was adiposity, classified using age-specific and sex-specific BMI SD scores (continuous) and obesity cut-offs (binary). Questionnaire-based measures comprised TV time, non-TV sitting time (such as homework, drawing, time at a computer or playing video games), total sitting time (TV time+non-TV sitting time) and average daily MVPA time. Objective SB and moderate to vigorous physical activity (MVPA) time were measured using an Actigraph GT1M accelerometer, with cut-offs of 100 and 200 counts per minute for SB, and 2802 counts per minute for MVPA. Multiple logistic and multiple linear regression models examined associations between each indicator of sedentary time with obesity and BMI SD scores. RESULTS: TV time (but not non-TV sitting or objectively-measured SB) was consistently associated with higher levels of obesity and BMI SD score, even after adjusting for MVPA and other potential confounders. Weaker associations were observed for total sitting time. CONCLUSIONS: TV viewing (but not other forms of objectively-measured or questionnaire-based sedentary time) was associated with obesity in children and adolescents. Although a causal relationship cannot be established, TV time may be a reasonable target for obesity prevention in young populations.

Physical inactivity among older adults: Implications for life expectancy among non-overweight and overweight or obese individuals.

This study investigates to what extent physical inactivity in older age is associated with reduced life expectancy among non-overweight and overweight/obese individuals. Data from 20,203 respondents aged ≥60 years were drawn from the Health Survey for England and Scottish Health Surveys (1994-2008) and 5-year all-cause mortality linkage. Population attributable fractions were calculated to estimate years of life lost due to physical inactivity. Physical inactivity was defined as not meeting the current UK physical activity guidelines for older adults. Not meeting physical activity guidelines was associated with reduced life expectancy that is larger among non-overweight individuals than among overweight/obese.

All cause mortality and the case for age specific alcohol consumption guidelines: pooled analyses of up to 10 population based cohorts.

OBJECTIVES: To examine the suitability of age specific limits for alcohol consumption and to explore the association between alcohol consumption and mortality in different age groups. DESIGN: Population based data from Health Survey for England 1998-2008, linked to national mortality registration data and pooled for analysis using proportional hazards regression. Analyses were stratified by sex and age group (50-64 and ≥ 65 years). SETTING: Up to 10 waves of the Health Survey for England, which samples the non-institutionalised general population resident in England. PARTICIPANTS: The derivation of two analytical samples was based on the availability of comparable alcohol consumption data, covariate data, and linked mortality data among adults aged 50 years or more. Two samples were used, each utilising a different variable for alcohol usage: self reported average weekly consumption over the past year and self reported consumption on the heaviest day in the past week. In fully adjusted analyses, the former sample comprised Health Survey for England years 1998-2002, 18,368 participants, and 4102 deaths over a median follow-up of 9.7 years, whereas the latter comprised Health Survey for England years 1999-2008, 34,523 participants, and 4220 deaths over a median follow-up of 6.5 years. MAIN OUTCOME MEASURE: All cause mortality, defined as any death recorded between the date of interview and the end of data linkage on 31 March 2011. RESULTS: In unadjusted models, protective effects were identified across a broad range of alcohol usage in all age-sex groups. These effects were attenuated across most use categories on adjustment for a range of personal, socioeconomic, and lifestyle factors. After the exclusion of former drinkers, these effects were further attenuated. Compared with self reported never drinkers, significant protective associations were limited to younger men (50-64 years) and older women (≥ 65 years). Among younger men, the range of protective effects was minimal, with a significant reduction in hazards present only among those who reported consuming 15.1-20.0 units/average week (hazard ratio 0.49, 95% confidence interval 0.26 to 0.91) or 0.1-1.5 units on the heaviest day (0.43, 0.21 to 0.87). The range of protective effects was broader but lower among older women, with significant reductions in hazards present ≤ 10.0 units/average week and across all levels of heaviest day use. Supplementary analyses found that most protective effects disappeared where calculated in comparison with various definitions of occasional drinkers. CONCLUSIONS: Beneficial associations between low intensity alcohol consumption and all cause mortality may in part be attributable to inappropriate selection of a referent group and weak adjustment for confounders. Compared with never drinkers, age stratified analyses suggest that beneficial dose-response relations between alcohol consumption and all cause mortality may be largely specific to women drinkers aged 65 years or more, with little to no protection present in other age-sex groups. These protective associations may, however, be explained by the effect of selection biases across age-sex strata.

Sedentary time in late childhood and cardiometabolic risk in adolescence.

BACKGROUND AND OBJECTIVE: There is a paucity of prospective evidence examining the links between sedentary time (ST) and cardiometabolic outcomes in youth. We examined the associations between objectively assessed ST and moderate to vigorous physical activity (MVPA) in childhood with cardiometabolic risk in adolescence. METHODS: The study included 4639 children (47% male) aged 11 to 12 years at baseline whose mothers were enrolled in ALSPAC (Avon Longitudinal Study of Parents and Children) during their pregnancy in the early 1990s. A total of 2963 children had valid blood samples at age 15 to 16 years. Associations with baseline ST and MVPA were examined for BMI, waist circumference, body fat mass, lean body mass, systolic and diastolic blood pressure, fasting triglycerides, total cholesterol, low-density lipoprotein and high-density lipoprotein (HDL) cholesterol, glucose, insulin, C-reactive protein, and a clustered standardized cardiometabolic risk score (CMscore). RESULTS: Baseline ST was not associated deleteriously with any cardiometabolic markers. MVPA was beneficially associated with the 3 adiposity indicators, lean body mass, systolic blood pressure, triglycerides, C-reactive protein, insulin, HDL cholesterol, and CMscore; once the models were adjusted for baseline levels of these markers, these associations remained for body fat mass (mean difference per 10 minutes of MVPA: -0.320 [95% confidence interval (CI): -0.438 to -0.203]; P < .001), HDL cholesterol (0.006 logged mmol/L [95% CI: 0.001 to 0.011]; P = .028), insulin (-0.024 logged IU/L [95% CI: -0.036 to -0.013]; P < .001), and CMscore (-0.014 [95% CI: -0.025 to -0.004]; P = .009). CONCLUSIONS: We found no evidence linking ST in late childhood with adverse cardiometabolic outcomes in adolescence. Baseline MVPA was beneficially linked to broad cardiometabolic health in adolescence.

Associations between objectively assessed and self-reported sedentary time with mental health in adults: an analysis of data from the Health Survey for England.

OBJECTIVE: There is increasing interest in the association between sedentary behaviour and mental health, although most studies have relied solely on self-reported measures, thus making results prone to various biases. The aim was to compare associations between objectively assessed and self-reported sedentary time with mental health in adults. SETTING: Community dwelling population sample drawn from the 2008 Health Survey for England. PARTICIPANTS: 11 658 (self-report analysis) and 1947 (objective data) men and women. PRIMARY OUTCOME: The 12-item General Health Questionnaire was administered to assess psychological distress. Sedentary and physical activity (exposure) was objectively measured using accelerometers (Actigraph GT1M) worn around the waist during waking hours for seven consecutive days. RESULTS: The highest tertile of objective sedentary time was associated with higher risk of psychological distress (multivariate adjusted OR=1.74, 95% CI 1.07 to 2.83), as was the highest tertile of self-reported total sitting time (OR=1.34, 95% CI 1.15 to 1.56). Self-reported, but not objective, moderate-to-vigorous physical activity was associated with lower risk of psychological distress. Only objective light-intensity activity was associated with lower risk of psychological distress. CONCLUSIONS: Sedentary time is associated with adverse mental health.

Measuring physical activity in children and adolescents for dietary surveys: practicalities, problems and pitfalls.

Physical inactivity is an important risk factor for many chronic diseases and contributes to obesity and poor mental well-being. The present paper describes the main advantages and disadvantages, practical problems, suggested uses, and future developments regarding self-reported and objective data collection in the context of dietary surveys. In dietary surveys, physical activity is measured primarily to estimate energy expenditure. Energy expenditure surveillance is important for tracking changes over time, particularly given the debates over the role of the relative importance of energy intake and expenditure changes in the aetiology of obesity. It is also important to assess the extent of underreporting of dietary intake in these surveys. Physical activity data collected should include details on the frequency, duration and relative intensity of activity for each activity type that contributes considerably to overall activity and energy expenditure. Problems of validity and reliability, associated with inaccurate assessment, recall bias, and social desirability bias, are well-known; children under 10 years cannot report their activities accurately. However, despite such limitations, questionnaires are still the dominant method of physical activity assessment in dietary surveys due to their low cost and relatively low participant burden. Objective, time-stamped measures that monitor heart rate and/or movement can provide more comprehensive, quantitative assessment of physical activity but at greater cost and participant burden. Although overcoming many limitations of questionnaires, objective measures also have drawbacks, including technical, practical and interpretational issues.

Objectively-assessed and self-reported sedentary time in relation to multiple socioeconomic status indicators among adults in England: a cross-sectional study.

OBJECTIVES: To examine the associations between socioeconomic position (SEP) and multidomain self-reported and objectively-assessed sedentary time (ST). DESIGN: Cross-sectional. SETTING: General population households in England. PARTICIPANTS: 2289 adults aged 16-96 years who participated in the 2008 Health Survey for England. OUTCOMES: 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. RESULTS: 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. CONCLUSIONS: Occupational sitting seems to drive the positive association between SEP and total ST. Lower SEP is linked to higher TV viewing times.

Physical activity and risk of all-cause and cardiovascular disease mortality in diabetic adults from Great Britain: pooled analysis of 10 population-based cohorts.

OBJECTIVE To examine associations between specific types of physical activity and all-cause and cardiovascular disease (CVD) mortality in a large nationally representative sample of adults with diabetes from Great Britain. RESEARCH DESIGN AND METHODS There were a total of 3,038 participants (675 deaths) with diabetes in the Health Survey for England and the Scottish Health Surveys conducted between 1997 and 2008. Participants aged ≥50 years at baseline were followed up for an average of 75.2 months for all-cause and CVD mortality. Data were collected on self-reported frequency, duration, and intensity of participation in sports and exercise, walking, and domestic physical activity, from which the number of MET-hours/week were derived. Sex-specific medians of time spent in each type of physical activity (for those physically active) were calculated, and Cox proportional hazards regression conducted to examine type-specific associations between the level of physical activity and all-cause and CVD mortality risk. RESULTS Inverse associations with all-cause and CVD mortality were observed for overall physical activity in a dose-response manner after adjusting for covariates. Compared with those who individuals were inactive, participants who reported some activity, but below the recommended amount, or who met the physical activity recommendations had a 26% (95% CI 39-11) and 35% (95% CI 47-21) lower all-cause mortality, respectively. Similar results were found for below/above median physical activity levels. Sports and exercise participation was inversely associated with all-cause (but not CVD) mortality, as were above average levels of walking. Domestic physical activity was not associated with mortality. CONCLUSIONS Moderate physical activity levels were associated with better prognosis in diabetic adults.

Children's and adolescents' sedentary behaviour in relation to socioeconomic position.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Are sitting occupations associated with increased all-cause, cancer, and cardiovascular disease mortality risk? A pooled analysis of seven British population cohorts.

BACKGROUND: There is mounting evidence for associations between sedentary behaviours and adverse health outcomes, although the data on occupational sitting and mortality risk remain equivocal. The aim of this study was to determine the association between occupational sitting and cardiovascular, cancer and all-cause mortality in a pooled sample of seven British general population cohorts. METHODS: The sample comprised 5380 women and 5788 men in employment who were drawn from five Health Survey for England and two Scottish Health Survey cohorts. Participants were classified as reporting standing, walking or sitting in their work time and followed up over 12.9 years for mortality. Data were modelled using Cox proportional hazard regression adjusted for age, waist circumference, self-reported general health, frequency of alcohol intake, cigarette smoking, non-occupational physical activity, prevalent cardiovascular disease and cancer at baseline, psychological health, social class, and education. RESULTS: In total there were 754 all-cause deaths. In women, a standing/walking occupation was associated with lower risk of all-cause (fully adjusted hazard ratio [HR] = 0.68, 95% CI 0.52-0.89) and cancer (HR = 0.60, 95% CI 0.43-0.85) mortality, compared to sitting occupations. There were no associations in men. In analyses with combined occupational type and leisure-time physical activity, the risk of all-cause mortality was lowest in participants with non-sitting occupations and high leisure-time activity. CONCLUSIONS: Sitting occupations are linked to increased risk for all-cause and cancer mortality in women only, but no such associations exist for cardiovascular mortality in men or women.