The association between sedentary behaviour, physical activity and type 2 diabetes markers: A systematic review of mixed analytic approaches.

The negative effect of sedentary behaviour on type 2 diabetes markers is established, but the interaction with measures of physical activity is still largely unknown. Previous studies have analysed associations with single-activity models, which ignore the interaction with other behaviours. By including results from various analytical approaches, this review critically summarises the effects of sedentary behaviour on diabetes markers and the benefits of substitutions and compositions of physical activity. Ovid Medline, Embase and Cochrane Library databases were systematically searched. Studies were selected if sedentary behaviour and physical activity were measured by accelerometer in the general population, and if associations were reported with glucose, insulin, HOMA-IR, insulin sensitivity, HbA1c, diabetes incidence, CRP and IL-6. Forty-five studies were included in the review. Conclusive detrimental associations with sedentary behaviour were determined for 2-h insulin (6/12 studies found associations), fasting insulin (15/19 studies), insulin sensitivity (4/6 studies), diabetes (3/4 studies) and IL-6 (2/3 studies). Reallocating sedentary behaviour to light or moderate-to-vigorous activity has a beneficial effect for 2-h glucose (1/1 studies), fasting insulin (3/3 studies), HOMA-IR (1/1 studies) and insulin sensitivity (1/1 studies). Compositional measures of sedentary behaviour were found to affect 2-h glucose (1/1 studies), fasting insulin (2/3 studies), 2-h insulin (1/1 studies), HOMA-IR (2/2 studies) and CRP (1/1 studies). Different analytical methods produced conflicting results for fasting glucose, 2-h glucose, 2-h insulin, insulin sensitivity, HOMA-IR, diabetes, hbA1c, CRP and IL-6. Studies analysing data by quartiles report independent associations between sedentary behaviour and fasting insulin, HOMA-IR and diabetes only for high duration of sedentary time (7-9 hours/day). However, this review could not provide sufficient evidence for a time-specific cut-off of sedentary behaviour for diabetes biomarkers. While substituting sedentary behaviour with moderate-to-vigorous activity brings greater improvements for health, light activity also benefits metabolic health. Future research should elucidate the effects of substituting and combining different activity durations and modalities.

Surge in SARS-CoV-2 transmission in school-aged children and household contacts, England, August to October 2021.

Easing of COVID-19 restrictions in England in the summer of 2021 was followed by a sharp rise in cases among school-aged children. Weekly rates of SARS-CoV-2 infection in primary and secondary school children reached 733.3 and 1,664.7/100,000 population, respectively, by week 39 2021. A surge in household clusters with school-aged index cases was noted at the start of the school term, with secondary cases predominantly in children aged 5-15 years and adults aged 30-49 years.

Priorities for the child public health response to the COVID-19 pandemic recovery in England.

Child health is at risk from the unintended consequences of the COVID-19 response and will suffer further unless it is given proper consideration. The pandemic can be conceived as a systemic shock to the wider determinants of child health, with impacts on family functioning and income, access to healthcare and education. This article outlines COVID-19 impacts on children in England. Key priorities relate to the diversion of healthcare during lockdown; interruption and return to schooling; increased health risks and long-term impacts on child poverty and social inequalities. We provide an overview of mitigation strategies and policy recommendations aimed to assist both national and local professionals across child health, education, social care and related fields to inform the policy response.

SARS-CoV-2 (COVID-19): What Do We Know About Children? A Systematic Review.

BACKGROUND: Few pediatric cases of coronavirus disease 2019 (COVID-19) have been reported and we know little about the epidemiology in children, although more is known about other coronaviruses. We aimed to understand the infection rate, clinical presentation, clinical outcomes, and transmission dynamics for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in order to inform clinical and public health measures. METHODS: We undertook a rapid systematic review and narrative synthesis of all literature relating to SARS-CoV-2 in pediatric populations. The search terms also included SARS-CoV and MERS-CoV. We searched 3 databases and the COVID-19 resource centers of 11 major journals and publishers. English abstracts of Chinese-language papers were included. Data were extracted and narrative syntheses conducted. RESULTS: Twenty-four studies relating to COVID-19 were included in the review. Children appear to be less affected by COVID-19 than adults by observed rate of cases in large epidemiological studies. Limited data on attack rate indicate that children are just as susceptible to infection. Data on clinical outcomes are scarce but include several reports of asymptomatic infection and a milder course of disease in young children, although radiological abnormalities are noted. Severe cases are not reported in detail and there are few data relating to transmission. CONCLUSIONS: Children appear to have a low observed case rate of COVID-19 but may have rates similar to adults of infection with SARS-CoV-2. This discrepancy may be because children are asymptomatic or too mildly infected to draw medical attention and be tested and counted in observed cases of COVID-19.

Patterns and correlates of active commuting in adults with type 2 diabetes: cross-sectional evidence from UK Biobank.

OBJECTIVES: To describe the active commuting (AC) patterns of adults with type 2 diabetes and how these relate to physical activity and sedentary behaviour in UK Biobank. Social and environmental correlates of AC will also be explored. DESIGN: Cross-sectional analysis of a cohort study. SETTINGS: This is a population cohort of over 500 000 people recruited from 22 centres across the UK. Participants aged between 37 and 73 years were recruited between 2006 and 2010. PARTICIPANTS: 6896 participants with a self-reported type 2 diabetes diagnosis who reported commuting to work and had complete covariate data were included in the analysis. EXPOSURE MEASURES: Exposure measures were AC to work, measured as usual mode of transport. OUTCOME MEASURES: Outcome measures were weekly minutes of moderate to vigorous physical activity (MVPA), hours/day of sedentary time and participation in active travel. RESULTS: AC (reporting walking or cycling to work only) was reported by 5.5% of participants, with the great majority using the car to commute (80%). AC was associated with an additional 73 (95% CI 10.8 to 134.9) and 105 (95% CI 41.7 to 167.2) weekly minutes of MVPA for men and women, respectively. AC was associated with reduced sedentary time (ß -1.1, 95% CI -1.6 to -0.7 hours/day for men; and ß -0.8, 95% CI -1.2 to -0.3 hours/day for women). Deprivation and distance from home to work were identified as correlates of AC behaviour. CONCLUSIONS: Rates of AC are very low in adults with type 2 diabetes. However, AC offers a potentially sustainable solution to increasing physical activity and reducing sedentary behaviour. Therefore, strategies to improve the environment and encourage AC may help to increase population levels of physical activity and reduce the disease burden associated with type 2 diabetes.

The Acute Effects of Breaking Up Seated Office Work With Standing or Light-Intensity Walking on Interstitial Glucose Concentration: A Randomized Crossover Trial.

BACKGROUND: The aim of this randomized, 3-period, 3-treatment crossover trial was to examine the acute effects of regularly breaking up seated office work with short bouts of standing or light-intensity walking on postprandial interstitial glucose concentration. METHODS: Seventeen middle-aged office workers performed 3 5-hour trial conditions at their workplace in a random order: 1) uninterrupted sitting, 2) sitting interrupted by 2 minutes of standing every 20 minutes, and 3) sitting interrupted by 2 minutes of light-intensity walking every 20 minutes. Participants consumed 2 standardized test drinks at the start of each trial condition and an iPro2 continuous glucose monitoring system (CGMS) recorded average interstitial glucose concentration every 5 minutes for the duration of the study. RESULTS: The 5-hour interstitial glucose incremental area under the curve (iAUC) was 55.5% lower after sitting interrupted by light-intensity walking compared with after uninterrupted sitting (95% CI, -104.2% to -6.8%). There was also a suggestion of a beneficial effect of regular standing breaks, particularly in overweight men, although they were not as effective as the walking breaks (mean difference [95% CI], -29.6% [-73.9% to 14.7%]). CONCLUSIONS: Regularly breaking up prolonged sitting lowers postprandial glycemia in middle-aged adults without metabolic impairment.

Evidence of moderation effects in predicting active transport to school.

Background: Distance from home to school is an important influence on the decision to use active transport (AT); however, ecological perspectives would suggest this relationship may be moderated by individual, interpersonal and environmental factors. This study investigates whether (i) gender, (ii) biological maturation, (iii) perceived family support for physical activity (PA) and (iv) multiple deprivation moderate the relationship between distance to school and AT. Methods: A total of 611 children (11-12 years old, 334 females) were recruited from schools in Leicestershire, UK. Gender, family support for PA, and AT were self-reported. Home and school postcodes were used to determine multiple deprivation and distance to school (km). Predicted age at peak height velocity was used to indicate biological maturation. Results: Logistic regressions revealed the main effects explained 40.2% of the variance in AT; however; distance to school was the only significant predictor. Further analyses revealed that distance to school had a greater negative impact on the use of AT in late-maturing (OR: 3.60, CI: 1.45-8.96), less deprived (OR: 3.54, CI: 1.17-10.72) and children with low family support of PA (OR: 0.26, CI: 0.11-0.61). Conclusions: This study provides evidence that, although distance to school might be the strongest predictor of AT, this relationship is complex.

The Potential Impact of Displacing Sedentary Time in Adults with Type 2 Diabetes.

PURPOSE: Sedentary time, in particular, prolonged unbroken sedentary time, is detrimental to health and displaces time spent in either light or moderate intensity physical activity. This cross-sectional study aimed to identify the potential impact of reallocating time from sedentary behaviors to more active behaviors on measures of body composition and metabolic health in people with type 2 diabetes. METHODS: Participants were 519 adults with newly diagnosed type 2 diabetes who had been recruited to the Early Activity in Diabetes (Early ACTID) randomized controlled trial. Waist-worn accelerometers were used to obtain objective measurement of sedentary time, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) at baseline alongside clinical measurements and fasting blood samples to determine cholesterol, triglycerides, HOMA-IR, and glucose. Isotemporal substitution modeling was performed to determine the potential impact of reallocating 30 min of sedentary time accumulated in a single bout (long bout) with 30 min of interrupted sedentary time, LPA, or MVPA. RESULTS: Sedentary time accounted for 65% of the waking day, of which 45% was accumulated in prolonged (≥30 min) bouts. Reallocation of 30 min of long-bout sedentary time with 30 min of short-bout sedentary time was associated with lower body mass index (BMI) (adjusted ß, -0.60; 95% confidence interval [CI], -1.00, -0.21) and waist circumference (WC) (adjusted ß, -1.16; 95% CI, -2.08, -0.25). Stronger effects were seen for LPA and MVPA. Reallocation of 30 min of long-bout sedentary time with LPA was associated with higher HDL-cholesterol (adjusted ß, 0.02; 95% CI, 0.00-0.03 mmol·L). CONCLUSIONS: Encouraging adults with newly diagnosed type 2 diabetes to break up prolonged periods of sedentary time may be an effective strategy for improving body composition and metabolic health.

Child obesity cut-offs as derived from parental perceptions: cross-sectional questionnaire.

BACKGROUND: Overweight children are at an increased risk of premature mortality and disease in adulthood. Parental perceptions and clinical definitions of child obesity differ, which may lessen the effectiveness of interventions to address obesity in the home setting. The extent to which parental and objective weight status cut-offs diverge has not been documented. AIM: To compare parental perceived and objectively derived assessment of underweight, healthy weight, and overweight in English children, and to identify sociodemographic characteristics that predict parental under- or overestimation of a child's weight status. DESIGN AND SETTING: Cross-sectional questionnaire completed by parents linked with objective measurement of height and weight by school nurses, in English children from five regions aged 4-5 and 10-11 years old. METHOD: Parental derived cut-offs for under- and overweight were derived from a multinomial model of parental classification of their own child's weight status against school nurse measured body mass index (BMI) centile. RESULTS: Measured BMI centile was matched with parent classification of weight status in 2976 children. Parents become more likely to classify their children as underweight when they are at the 0.8th centile or below, and overweight at the 99.7th centile or above. Parents were more likely to underestimate a child's weight if the child was black or South Asian, male, more deprived, or the child was older. These values differ greatly from the BMI centile cut-offs for underweight (2nd centile) and overweight (85th). CONCLUSION: Clinical and parental classifications of obesity are divergent at extremes of the weight spectrum.

Accelerometer-measured sedentary time and cardiometabolic biomarkers: A systematic review.

OBJECTIVE: We conducted a systematic review to investigate the cross-sectional and prospective associations of accelerometer-measured total sedentary time and breaks in sedentary time with individual cardiometabolic biomarkers in adults ≥18years of age. METHODS: Ovid Medline, Embase, Web of Science and the Cochrane Library were searched for studies meeting the inclusion criteria. Due to inconsistencies in the measurement and analysis of sedentary time, data was synthesised and presented narratively rather than as a meta-analysis. RESULTS: Twenty-nine studies were included in the review; twenty-eight reported on total sedentary time and six on breaks in sedentary time. There was consistent evidence from cross-sectional data of an unfavourable association between total sedentary time and insulin sensitivity. There was also some evidence that total sedentary time was unfavourably associated with fasting insulin, insulin resistance and triglycerides. Furthermore, there was some evidence from cross-sectional data of a favourable association between breaks in sedentary time and triglycerides. CONCLUSION: Total sedentary time was consistently shown to be associated with poorer insulin sensitivity, even after adjusting for time spent in physical activity. This finding supports the proposed association between sedentary time and the development of Type 2 diabetes and reinforces the need to identify interventions to reduce time spent sedentary.

Longitudinal changes in sedentary time and physical activity during adolescence.

BACKGROUND: Low levels of physical activity and high time spent in sedentary activities have been associated with unfavourable health outcomes in adolescents. During adolescence, physical activity declines and sedentary time increases, however little is known about whether the magnitude of these changes differs within or between school-time, after-school time, or at weekends. METHODS: Adolescents (n = 363) participating in the PEACH (Personal and Environmental Associations with Children's Health) project provided accelerometer data at 12 and 15 years of age. Data were collected in 2008/2009 and 2012/2013. Time spent sedentary (<100 cpm), in light physical activity (LPA (100-2295 cpm) and in moderate to vigorous physical activity (MVPA: ≥ 2296 cpm) were generated for school-time, after-school time and for weekends using school-specific start and finish times. All data were analysed in 2014. RESULTS: The proportion of time spent sedentary significantly increased during school (+8.23%, 95% CI = 7.35 to 9.13), after-school (+6.99%, 95% CI = 5.91 to 8.07) and at weekends (+6.86%, 95% CI = 5.10 to 8.62). A parallel decrease was found in the proportion of time spent in LPA during school (-7.62%, 95% CI = -8.26 to -6.98), after-school (-7.01%, 95% CI = -7.74 to -6.28) and at weekends (-6.72%, 95% CI = -7.80 to -5.65). The proportion of time spent in MVPA remained relatively stable during school (-0.64, 95% CI = -1.11 to -0.18), after-school (0.04%, 95% CI = -0.58 to 0.67) and at weekends (-0.14%, 95% CI = -1.18 to 0.90). CONCLUSIONS: Objectively measured sedentary time increased between 12 and 15 years of age during-school, after-school, and at weekends, suggesting that interventions aiming to reduce the age-associated changes in sedentary time are needed in all three time contexts. Future work should identify which sedentary activities change more than others to inform interventions which aim to minimise the increase in time spent sedentary during adolescence.

The tracking of active travel and its relationship with body composition in UK adolescents.

BACKGROUND: To examine the tracking of active travel through adolescence, and its association with body mass index (BMI) and fat mass at age 17 in a UK cohort. METHODS: We analysed data collected from the Avon Longitudinal Study of Parents and Children (ALSPAC). The analyses include all participants with self-reported travel mode to school at ages 12, 14 and 16 years, and measured height, weight and body composition at age 17 (n=2,026). Tracking coefficients were calculated for individual travel behaviours (including walking and cycling) through adolescence using Generalised Estimating Equations. Linear regression analyses examined associations between travel pattern (consistently passive, consistently active, active at two time points or active at one time point), BMI, and DXA-measured fat mass (expressed as internally derived standard deviation scores) at 17 years. Analyses were adjusted for height (where appropriate), sex, age, parental social class, and maternal education with interaction terms to assess sex differences. RESULTS: There was substantial tracking in active travel through adolescence, with 38.5% of males and 32.3% of females consistently walking or cycling to school. In males, a consistently or predominantly active travel pattern was associated with a lower BMI SD score at age 17 (consistently active: adjusted ß=-0.23; 95% CI -0.40, -0.06; active at two time points: adjusted ß-0.30; 95% CI -0.50, -0.10) compared to those with a consistently passive pattern. No associations were seen in females. CONCLUSIONS: Maintenance of active travel behaviours throughout adolescence may help to protect against the development of excess BMI in males. In addition to encouraging the adoption of active travel to school, public health messages should aim to prevent drop out from active travel to promote good health in youth.

The benefits and harms of providing parents with weight feedback as part of the national child measurement programme: a prospective cohort study.

BACKGROUND: Small-scale evaluations suggest that the provision of feedback to parents about their child's weight status may improve recognition of overweight, but the effects on lifestyle behaviour are unclear and there are concerns that informing parents that their child is overweight may have harmful effects. The aims of this study were to describe the benefits and harms of providing weight feedback to parents as part of a national school-based weight-screening programme in England. METHODS: We conducted a pre-post survey of 1,844 parents of children aged 4-5 and 10-11 years who received weight feedback as part of the 2010-2011 National Child Measurement Programme. Questionnaires assessed general knowledge about the health risks associated with child overweight, parental recognition of overweight and the associated health risks in their child, child lifestyle behaviour, child self-esteem and weight-related teasing, parental experience of the feedback, and parental help-seeking behaviour. Differences in the pre-post proportions of parents reporting each outcome were assessed using a McNemar's test. RESULTS: General knowledge about child overweight as a health issue was high at baseline and increased further after weight feedback. After feedback, the proportion of parents that correctly recognised their child was overweight increased from 21.9% to 37.7%, and more than a third of parents of overweight children sought further information regarding their child's weight. However, parent-reported changes in lifestyle behaviours among children were minimal, and limited to increases in physical activity in the obese children only. There was some suggestion that weight feedback had a greater impact upon changing parental recognition of the health risks associated with child overweight in non-white ethnic groups. CONCLUSIONS: In this population-based sample of parents of children participating in the National Child Measurement Programme, provision of weight feedback increased recognition of child overweight and encouraged some parents to seek help, without causing obvious unfavourable effects. The impact of weight feedback on behaviour change was limited; suggesting that further work is needed to identify ways to more effectively communicate health information to parents and to identify what information and support may encourage parents in making and maintaining lifestyle changes for their child.

Predictors of health-related behaviour change in parents of overweight children in England.

OBJECTIVE: Providing parents with information about their child's overweight status (feedback) could prompt them to make lifestyle changes for their children. We assessed whether parents of overweight children intend to or change behaviours following feedback, and examined predictors of these transitions. METHODS: We analysed data from a cohort of parents of children aged 4-5 and 10-11 years participating in the National Child Measurement Programme in five areas of England, 2010-2011. Parents of overweight children (body mass index ≥91st centile) with data at one or six months after feedback were included (n=285). The outcomes of interest were intention to change health-related behaviours and positive behaviour change at follow-up. Associations between respondent characteristics and outcomes were assessed using logistic regression analysis. RESULTS: After feedback, 72.1% of parents reported an intention to change; 54.7% reported positive behaviour change. Intention was associated with recognition of child overweight status (OR 11.20, 95% CI 4.49, 27.93). Parents of older and non-white children were more likely to report behaviour changes than parents of younger or white children. Intention did not predict behaviour change. CONCLUSIONS: Parental recognition of child overweight predicts behavioural intentions. However, intentions do not necessarily translate into behaviours; interventions that aim to change intentions may have limited benefits.

Can the relationship between ethnicity and obesity-related behaviours among school-aged children be explained by deprivation? A cross-sectional study.

OBJECTIVES: It is unclear whether cultural differences or material disadvantage explain the ethnic patterning of obesogenic behaviours. The aim of this study was to examine ethnicity as a predictor of obesity-related behaviours among children in England, and to assess whether the effects of ethnicity could be explained by deprivation. SETTING: Five primary care trusts in England, 2010-2011. PARTICIPANTS: Parents of white, black and South Asian children aged 4-5 and 10-11 years participating in the National Child Measurement Programme (n=2773). PRIMARY OUTCOME MEASURES: Parent-reported measures of child behaviour: low level of physical activity, excessive screen time, unhealthy dietary behaviours and obesogenic lifestyle (combination of all three obesity-related behaviours). Associations between these behaviours and ethnicity were assessed using logistic regression analyses. RESULTS: South Asian ethnic groups made up 22% of the sample, black ethnic groups made up 8%. Compared with white children, higher proportions of Asian and black children were overweight or obese (21-27% vs16% of white children), lived in the most deprived areas (24-47% vs 14%) and reported obesity-related behaviours (38% with obesogenic lifestyle vs 16%). After adjusting for deprivation and other sociodemographic characteristics, black and Asian children were three times more likely to have an obesogenic lifestyle than white children (OR 3.0, 95% CI 2.1 to 4.2 for Asian children; OR 3.4, 95% CI 2.7 to 4.3 for black children). CONCLUSIONS: Children from Asian and black ethnic groups are more likely to have obesogenic lifestyles than their white peers. These differences are not explained by deprivation. Culturally specific lifestyle interventions may be required to reduce obesity-related health inequalities.

Improving prediction algorithms for cardiometabolic risk in children and adolescents.

Clustering of abnormal metabolic traits, the Metabolic Syndrome (MetS), has been associated with an increased cardiovascular disease (CVD) risk. Several algorithms including the MetS and other risk factors exist for adults to predict the risk of CVD. We discuss the use of MetS scores and algorithms in an attempt to predict later cardiometabolic risk in children and adolescents and offer suggestions for developing clinically useful algorithms in this population. There is little consensus in how to define the MetS or to predict future CVD risk using the MetS and other risk factors in children and adolescents. The MetS scores and prediction algorithms we identified had usually not been tested against a clinical outcome, such as CVD, and they had not been validated in other populations. This makes comparisons of algorithms impossible. We suggest a simple two-step approach for predicting the risk of adult cardiometabolic disease in overweight children. It may have advantages in terms of cost-effectiveness since it uses simple measurements in the first step and more complex, costly measurements in the second step. It also takes advantage of the continuous distributions of the metabolic features. We suggest piloting and validating any new algorithms.

Perceptions of health risk among parents of overweight children: a cross-sectional study within a cohort.

OBJECTIVE: To identify the socio-demographic and behavioural characteristics associated with perceptions of weight-related health risk among the parents of overweight children. METHODS: Baseline data from a cohort of parents of children aged 4-11 years in five areas in England in 2010-2011 were analysed; the sample was restricted to parents of overweight children (body mass index ≥ 91(st) centile of UK 1990 reference; n=579). Associations between respondent characteristics and parental perception of health risk associated with their child's weight were examined using logistic regression analyses. RESULTS: Most parents (79%) did not perceive their child's weight to be a health risk. Perception of a health risk was associated with recognition of the child's overweight status (OR 10.59, 95% CI 5.51 to 20.34), having an obese child (OR 4.21, 95% CI 2.28 to 7.77), and having an older child (OR 2.67, 95% CI 1.32 to 5.41). However, 41% of parents who considered their child to be overweight did not perceive a health risk. CONCLUSIONS: Parents that recognise their child's overweight status, and the parents of obese and older children, are more likely to perceive a risk. However, many parents that acknowledge their child is overweight do not perceive a related health risk.

Scoping the impact of the national child measurement programme feedback on the child obesity pathway: study protocol.

BACKGROUND: The National Child Measurement Programme was established to measure the height and weight of children at primary school in England and provides parents with feedback about their child's weight status. In this study we will evaluate the impact of the National Child Measurement Programme feedback on parental risk perceptions of overweight, lifestyle behaviour and health service use. METHODS: The study will be a prospective cohort study of parents of children enrolled in the National Child Measurement Programme and key service providers from 5 primary care trusts (administrative bodies responsible for providing primary and secondary care services). We will conduct baseline questionnaires, followed by provision of weight feedback and 3 follow up questionnaires over the course of a year. Questionnaires will measure change in parental risk perception of overweight, health behaviours and health service use. Qualitative interviews will be used to identify barriers and facilitators to change. This study will produce preliminary data on National Health Service costs associated with weight feedback and determine which feedback approach (letter and letter plus telephone) is more effective. DISCUSSION: This study will provide the first large scale evaluation of the National Child Measurement Programme feedback. Findings from this evaluation will inform future planning of the National Child Measurement Programme.