Associations between metabolic syndrome components and markers of inflammation in Welsh school children.

We investigated the multivariate dimensionality and strength of the relationship between metabolic syndrome (MetS) and inflammation in children. Caucasian school children (N = 229; 12-14 years) from Wales were tested on several health indicators including measures of body composition, inflammation, fasting glucose regulation, blood pressure, and lipids. The multivariate association between MetS and inflammation was investigated via canonical correlation analysis. Data were corrected for non-normality by log transformation, and sex-specific z-scores computed for variables where there was a significant sex difference. Structure r's were interpreted to determine the dimensions of MetS and inflammation responsible for significant canonical variates. The overall multivariate association between MetS and inflammation was significant (Wilks' Lambda = 0.54, p < 0.001). The relationship was explained primarily by the waist circumference dimension of MetS (CC = 0.87) and inflammatory markers of fibrinogen (CC = 0.52) and C-reactive protein (CC = 0.50). The pattern of results was similar regardless of whether variables were adjusted for sex differences. CONCLUSION: Central adiposity is the strongest predictor of the inflammatory aspect of cardiovascular disease risk in Caucasian adolescents. Future research into MetS and cardiometabolic risk should consider multivariate statistical approaches, in order to identify the separate contributions of each dimension in interrelationships and to identify which dimensions are influenced by preventive interventions. What is Known: • Metabolic syndrome (MetS) is associated with increased risk of cardiovascular disease (CVD) and type 2 diabetes. Markers of inflammation are also potential predictors of later development of CVD and type 2 diabetes. • The contribution of individual markers in interrelationships between MetS and inflammation is unknown. What is New: • We uniquely demonstrate that within a multivariate model, waist circumference is the primary link between MetS variables and markers of inflammation in children. • Waist circumference may therefore be a useful population-level screening tool to identify future risk of CVD.

Research priorities for child and adolescent physical activity and sedentary behaviours: an international perspective using a twin-panel Delphi procedure.

BACKGROUND: The quantity and quality of studies in child and adolescent physical activity and sedentary behaviour have rapidly increased, but research directions are often pursued in a reactive and uncoordinated manner. AIM: To arrive at an international consensus on research priorities in the area of child and adolescent physical activity and sedentary behaviour. METHODS: Two independent panels, each consisting of 12 experts, undertook three rounds of a Delphi methodology. The Delphi methodology required experts to anonymously answer questions put forward by the researchers with feedback provided between each round. RESULTS: The primary outcome of the study was a ranked set of 29 research priorities that aimed to be applicable for the next 10 years. The top three ranked priorities were: developing effective and sustainable interventions to increase children's physical activity long-term; policy and/or environmental change and their influence on children's physical activity and sedentary behaviour; and prospective, longitudinal studies of the independent effects of physical activity and sedentary behaviour on health. CONCLUSIONS: These research priorities can help to guide decisions on future research directions.

Effects of a novel school-based cross-curricular physical activity intervention on cardiovascular disease risk factors in 11- to 14-year-olds: the activity knowledge circuit.

PURPOSE: This study investigates cardiovascular disease risk factor response in adolescents following introduction of brisk walking into curriculum lessons. DESIGN: Quasi-experimental. SETTING: School-based. SUBJECTS: An intervention group consisted of 115 (aged 12.4 ± 0.5 y) year eight participants, and 77 (aged 12.1 ± 1.1 y) year seven and year nine participants formed a control. INTERVENTION: An 18-week cross-curricular physical activity intervention was implemented in one secondary school. MEASURES: Adiposity variables, blood pressure, lipids, lipoproteins, glucose, insulin, high-sensitivity C-reactive protein, high-molecular-weight adiponectin, aerobic fitness, physical activity behavior, and diet were assessed preintervention and postintervention. ANALYSIS: Dependent and independent t-tests. RESULTS: Prevalence of elevated waist circumference (9.8% vs. 6.9%), systolic blood pressure (3.3% vs. 0%), triglycerides (2.5% vs. 1.2%), and reduced high density lipoprotein cholesterol (3.7% vs. 2.7%) decreased in the intervention group. Significant improvements in high density lipoprotein cholesterol to total cholesterol ratio (mean ± SD: 2% ± 4% [confidence interval (CI)(0.05)  =  1% to 2%], t(80)  =  -3.5, p  =  .001) and glucose (-.1 ± .4 mmol/L [CI(0.05)  =  -.2% to 0%], t(79)  =  3.2, p  =  .002) were evident for the intervention group. CONCLUSION: The Activity Knowledge Circuit may prove to be a sustainable, effective, and cost-effective strategy to engage schoolchildren in physical activity on a daily basis. A longer-duration intervention is required to fully understand risk factor response in adolescents.

ROC generated thresholds for field-assessed aerobic fitness related to body size and cardiometabolic risk in schoolchildren.

OBJECTIVES: 1. to investigate whether 20 m multi-stage shuttle run performance (20mSRT), an indirect measure of aerobic fitness, could discriminate between healthy and overweight status in 9-10.9 yr old schoolchildren using Receiver Operating Characteristic (ROC) analysis; 2. Investigate if cardiometabolic risk differed by aerobic fitness group by applying the ROC cut point to a second, cross-sectional cohort. DESIGN: Analysis of cross-sectional data. PARTICIPANTS: 16,619 9-10.9 year old participants from SportsLinx project and 300 11-13.9 year old participants from the Welsh Schools Health and Fitness Study. OUTCOME MEASURES: SportsLinx; 20mSRT, body mass index (BMI), waist circumference, subscapular and superilliac skinfold thicknesses. Welsh Schools Health and Fitness Study; 20mSRT performance, waist circumference, and clustered cardiometabolic risk. ANALYSES: Three ROC curve analyses were completed, each using 20mSRT performance with ROC curve 1 related to BMI, curve 2 was related to waist circumference and 3 was related to skinfolds (estimated % body fat). These were repeated for both girls and boys. The mean of the three aerobic fitness thresholds was retained for analysis. The thresholds were subsequently applied to clustered cardiometabolic risk data from the Welsh Schools study to assess whether risk differed by aerobic fitness group. RESULTS: The diagnostic accuracy of the ROC generated thresholds was higher than would be expected by chance (all models AUC >0.7). The mean thresholds were 33 and 25 shuttles for boys and girls respectively. Participants classified as 'fit' had significantly lower cardiometabolic risk scores in comparison to those classed as unfit (p<0.001). CONCLUSION: The use of the ROC generated cut points by health professionals, teachers and coaches may provide the opportunity to apply population level 'risk identification and stratification' processes and plan for "at-risk" children to be referred onto intervention services.

Pubertal stage and measures of adiposity in British schoolchildren.

BACKGROUND: Puberty is a critical period in the development of obesity. Body mass index (BMI), waist circumference and skin-fold thickness are used generally as estimates of body fat in children and adults. AIM: To identify a marker of adiposity that is independent of pubertal status and determine its relationship to physical fitness in adolescence. SUBJECTS AND METHODS: Girls (n = 147) and boys (n = 100) from year 8 in three Welsh schools self-reported Tanner stages. Anthropometric measurements of adiposity were made and aerobic fitness estimated with a 20-metre shuttle-run test. RESULTS: Children in early and late puberty were of similar chronological age. BMI strongly correlated with height in early puberty in girls (r = 0.366, p < 0.001) and boys (r = 0.594, p < 0.001), but not in late puberty. Waist-to-height ratio adjusted for the effect of height on waist measurements; and correlated with percentage fat mass in early and late puberty in girls (r = 0.865 and r = 0.772, both p < 0.001) and boys (r = 0.868 and r = 0.877, both p < 0.001). Physical fitness score was inversely related to waist-to-height ratio, with similar regression lines in early and late puberty, in girls (r = - 0.545, p < 0.001 and r = - 0.362, p = 0.005) and boys (r = - 0.490, p < 0.001 and r = - 0.400, p = 0.003). CONCLUSION: Pubertal status should be taken into account in adjusting weight for height in adolescents. Waist-to-height ratio is a convenient and appropriate measure of adiposity during puberty.

Physical activity behaviour: an overview of current and emergent theoretical practices.

Physical activity research has been dominated by traditional cognitive rationale paradigms utilized within other domains. Though this approach to physical activity behavior has greatly enhanced our understanding of the key determinants, it has done little to eradicate the health problems we currently face. In order to achieve lasting change though, multilevel interventions may prove effective. Ecological perspectives have been proposed as an effective approach in combating current physical inactivity levels. Nevertheless, this approach is in its infancy and much has still to be learned. The aim of this paper is to provide an overview of the main behavioral models used within the physical activity domain while proposing the need for further models that will embrace the principles presented by ecological and complexity theories.

Prevalence of traditional and novel markers of cardiovascular disease risk in Scottish adolescents: socioeconomic effects.

Information on the health status and physical activity of Scottish adolescents is limited. This study examines the prevalence of cardiovascular disease (CVD) risk in Scottish adolescents by socioeconomic status (SES). Participants were recruited from two high schools that differed in the SES of the students in attendance. The sample included 73 boys and 34 girls (16.4 ± 0.6 years). Variables included anthropometry, physical activity, physical fitness, blood pressure, diet, and 11 metabolic markers of CVD risk. Significant sex differences (P ≤ 0.01) were noted for stature, waist circumference, waist-hip ratio, physical activity, cardiorespiratory fitness, muscular power, sprint speed, and several CVD risk factors: high-density lipoprotein (HDL), low-density lipoprotein (LDL), interleukin-6 (IL-6), and C-reactive protein (CRP) levels. Boys from a lower SES had significantly higher levels of glucose and plasminogen activator inhibitor-1 (PAI-1) but lower levels of adiponectin compared with boys from a higher SES. Girls from a lower SES had significantly (P ≤ 0.01) higher glucose and PAI-1 levels but lower levels of insulin and adiponectin than girls from a higher SES. High fat diets, low physical activity levels, and elevated CRP and total cholesterol levels were the CVD risk factors most commonly identified as being at-risk levels in this cohort, regardless of sex or SES. SES differences were not consistently apparent, but several CVD risk factors were identified as elevated in this sample of adolescents, regardless of sex or SES.

Child fitness and father's BMI are important factors in childhood obesity: a school based cross-sectional study.

BACKGROUND: This study examines obesity and factors associated with obesity in children aged 11-13 years in the UK. METHODS: 1147 children from ten secondary schools participated in a health survey that included blood samples, fitness test and anthropometric measures. Factors associated with obesity were examined using multilevel logistic regression. FINDINGS: Of the children examined (490 male; 657 female) a third were overweight, 1 in 6 had elevated blood pressure, more than 1 in 10 had high cholesterol, 58% consumed more fat than recommended, whilst 37% were classified as unfit. Children in deprived areas had a higher proportion of risk factors; for example, they had higher blood pressure (20% (deprived) compared to 11% (non-deprived), difference: 9.0% (95%CI: 4.7%-13.4%)). Obesity is associated with risk factors for heart disease and diabetes. Maintaining fitness is associated with a reduction in the risk factors for heart disease (high blood pressure and cholesterol) but not on risk factors for diabetes (insulin levels). In order of importance, the main risk factors for childhood obesity are being unfit, having an obese father, and being large at birth. CONCLUSION: The high proportion of children with risk factors suggests future interventions need to focus on community and policy change to shift the population norm rather than targeting the behaviour of high risk individuals. Interventions need to focus on mothers' lifestyle in pregnancy, fathers' health, as well as promoting fitness among children. Obesity was not associated with deprivation. Therefore, strategies should be adopted in both deprived and non deprived areas.

Exercise duration and blood lactate concentrations following high intensity cycle ergometry.

The aim of this study was to investigate differences in blood lactate accumulation following 10 and 20 sec of maximal cycle ergometer exercise. Body mass, stature, and age of the group was determined prior to testing (82.57 ± 5.94 kg 177 ± 5.94 cm and 21.42 ± 1.61 yrs, respectively). Eight male rugby union players performed two maximal sprints in a random fashion of 10 and 20 sec duration on a cycle ergometer. During the 10 and 20 sec trial, blood lactate levels measured were as follows 1.58 ± 0.78, 4.43 ± 1.4, and 3.5 ± 1.2 mmol.l⁻¹ vs. 1.72 ± 0.65, 6.14 ± 2, and 5.68 ± 2.22 mmol.l⁻¹, respectively. Differences were found (P < 0.01) from rest to 5 and 10 min postexercise in both groups. Differences in concentration also were found between groups at both postexercise stages (P < 0.01). The reduction in blood lactate concentrations observed between the 5 to 10 min recovery stages were 0.91 ± 0.58 mmol.l⁻¹ vs. 0.46 ± 0.48 mmol.l⁻¹ following 10 and 20 sec of maximal exercise, respectively (P > 0.05). The concentrations observed are interesting and may influence recovery time and subsequent exercise performance.

Novel risk factors of cardiovascular disease and their associations between obesity, physical activity and physical fitness.

The prevalence of cardiovascular disease (CVD) is increasing around the globe and is the leading cause of death around the world. Though once thought of as an adult problem, it is now recognised that the early manifestations of disease may occur during childhood. Numerous risk factors have been linked to CVD with much of the research focusing on understanding the prevalence and relationship of traditional risk factors such as dyslipidemia, smoking, diabetes mellitus, hypertension, obesity, psychosocial stress, poor diet, physical inactivity and alcohol consumption to the early etiology of disease. While this line of investigation has greatly enhanced our understanding of the relationship between these risk factors and disease, they do not fully explain all cardiovascular events. To enhance our understanding and help with the management of CVD, investigations that involve the measurement of traditional as well as novel risk factors may be necessary. Public health strategies that aim to reduce the prevalence of obesity and overweight encourage youth to increase their physical activity levels as a means of protecting against poor cardiometabolic profiles. Interventions that increase physical activity levels and improve cardiorespiratory fitness cause a reduction in certain CVD risk factors but the lack of agreement between findings makes it impossible to give precise recommendations that will ensure CVD risk reduction. Yet it is important that research continues in order to establish the most appropriate means of improving the health and well-being of those at most risk of future CVD.

The effects of a novel high intensity exercise intervention on established markers of cardiovascular disease and health in Scottish adolescent youth.

UNLABELLED: This study examined the effects of high intensity exercise on physical fitness components and cardiovascular disease (CVD) risk factors in youth. Forty-one participants (15-17 years) were divided into a control and an intervention (high intensity exercise, HIT) group. The HIT group (15 boys, 2 girls) performed three weekly sessions over seven weeks consisting of either four to six repeats of maximal sprint running with 20-30 s recovery. The control group (20 boys, 4 girls) continued their normal activity patterns. All participants had indices of obesity and blood pressure (BP) recorded in addition to four physical performance measures pre-and post-intervention: cardiorespiratory fitness, muscular power, sprint speed and agility. In the HIT group, significant improvements in cardiorespiratory fitness (P<0.01) and agility (P<0.05) were noted. Participants in the control group, meanwhile, experienced a significant decrease in counter movement jump performance. These findings demonstrate that brief, intense exercise interventions are useful for improving indices of physical fitness in a short period of time. ACKNOWLEDGMENTS: The authors gratefully acknowledge Ms. Maini Tulokas in the Social Insurance Institution for her skilled help in preparing the figures. FUNDING: this study was financially supported by the Chief Scientist Office for Scotland.

Recommendations to improve physical activity among teenagers--a qualitative study with ethnic minority and European teenagers.

BACKGROUND: To understand the key challenges and explore recommendations from teenagers to promote physical activity with a focus on ethnic minority children. METHODS: Focus groups with teenagers aged 16-18 of Bangladeshi, Somali or Welsh descent attending a participating school in South Wales, UK. There were seventy four participants (18 Somali, 24 Bangladeshi and 32 Welsh children) divided into 12 focus groups. RESULTS: The boys were more positive about the benefits of exercise than the girls and felt there were not enough facilities or enough opportunity for unsupervised activity. The girls felt there was a lack of support to exercise from their family. All the children felt that attitudes to activity for teenagers needed to change, so that there was more family and community support for girls to be active and for boys to have freedom to do activities they wanted without formal supervision. It was felt that older children from all ethnic backgrounds should be involved more in delivering activities and schools needs to provide more frequent and a wider range of activities. CONCLUSIONS: This study takes a child-focused approach to explore how interventions should be designed to promote physical activity in youth. Interventions need to improve access to facilities but also counteract attitudes that teenagers should be studying or working and not 'hanging about' playing with friends. Thus, the value of activity for teenagers needs to be promoted not just among the teenagers but with their teachers, parents and members of the community.

The effects of time and intensity of exercise on novel and established markers of CVD in adolescent youth.

OBJECTIVES: This article examines the effects of brief, intense exercise in comparison with traditional endurance exercise on both novel and traditional markers of cardiovascular disease (CVD) in youth. METHODS: Forty seven boys and ten girls (16.4 ± 0.7 years of age) were divided into a moderate (MOD), high intensity (HIT), or a control group. The MOD group (12 boys, 4 girls) and HIT group (15 boys, 2 girls) performed three weekly exercise sessions over 7 weeks. Each session consisted of either four to six repeats of maximal sprint running within a 20 m area with 20-30 s recovery (HIT) or 20 min continuous running within a 20 m area at ∼70% maximal oxygen uptake (VO(2) max). RESULTS: Total exercise time commitment over the intervention was 420 min (MOD) and 63 min (HIT). Training volume was 85% lower for the HIT group. Total estimated energy expenditure was ∼907.2 kcal (HIT) and ∼4410 kcal (MOD). Significant improvements (P ≤ 0.05) were found in systolic blood pressure, aerobic fitness, and body mass index (BMI) postintervention (HIT). In the MOD group, significant (P ≤ 0.05) improvements were noted in aerobic fitness, percentage body fat (%BF), BMI, fibrinogen (Fg), plasminogen activator inhibitor-1, and insulin concentrations. CONCLUSIONS: These findings demonstrate that brief, intense exercise is a time efficient means for improving CVD risk factors in adolescents.

Parental factors associated with walking to school and participation in organised activities at age 5: analysis of the Millennium Cohort Study.

BACKGROUND: Physical activity is associated with better health. Two sources of activity for children are walking to school and taking part in organised sports and activities. This study uses a large national cohort to examine factors associated with participation in these activities. METHODS: The Millennium Cohort study contains 5 year follow-up of 17,561 singleton children recruited between 2000-2002 in the UK. All participants were interviewed in their own homes at 9 months, 3 years and 5 years follow-up and all measures were self reports. Logistic regression and likelihood ratio tests were used. RESULTS: Children are less likely to walk to school as income and parental education increase [Adjusted odds: 0.7 (95%CI: 0.6-0.8) for higher income/education compared to low income/no qualifications]. However, if the parent plays with the child in high income families the child is more likely to walk to school [Adjusted odds: 1.67 (95%CI: 1.3-2.1)]. Children taking part in organised activities are from higher income, higher education families, with a car, in a "good" area with non-working mothers. However, in low socio-economic families where the parent plays with the child the child is more likely to take part in organised activities [Adjusted odds: 2.0 (95% CI: 1.5-2.7)]. CONCLUSIONS: Income is an important determinant of the type of activity available to children. Families that report good health behaviours (non-smoking, low TV viewing) and play with their children show higher levels of physical activity. Thus, parenting practice appears to have a strong impact on their child's physical activity.

Serum oxidant and antioxidant status during early and late recovery periods following an all-out 21-km run in trained adolescent runners.

It is well documented that intense exercise precipitates oxidative stress in adults. However, there is lack of related studies concerning oxidant and antioxidant status during early and late recovery periods in adolescent athletes, following endurance exercise in particular. This study investigated aspects of the serum oxidant and antioxidant status of 12 male adolescent (16.2 ± 0.6 years) trained runners during early and late recovery periods after an all-out 21-km run. Venous blood samples were taken immediately before, 2 and 4 h following (early recovery period), and 24 h following (late recovery period) the 21-km run. Samples were analyzed for serum concentrations of thiobarbituric acid-reactive substances (TBARS), uric acid (UA), reduced glutathione (GSH), and enzymatic activity of xanthine oxidase (XO), superoxide dismutase (SOD), and catalase (CAT). During the early recovery period, there were increases in the 4-h GSH (194.8 ± 10.4 vs. 211.8 ± 11.4 mg l(-1), P < 0.05), 2- and 4-h UA (307.8 ± 68.6 vs. 327.4 ± 63.8; 330.2 ± 65.1 µmol l(-1), P < 0.05), and 2-h CAT (2.05 ± 0.44 vs. 3.07 ± 0.51 U ml(-1), P < 0.05), and decreases in the 2-h XO (11.1 ± 1.5 vs. 10.3 ± 1.2 U l(-1), P < 0.05) compared to the corresponding pre-exercise level, respectively. No change was observed in SOD (P > 0.05). At the late recovery period, there was an increase in CAT (2.80 ± 0.49 U ml(-1), P < 0.05) and TBARS (2.99 ± 0.83 vs. 4.40 ± 1.38 nmol ml(-1), P < 0.05). These data indicate that although the antioxidant capacity of adolescent runners is augmented during the early recovery period following the 21-km run, they were not completely protected from oxidative stress during the later recovery period.

Protocol of the baseline assessment for the Environments for Healthy Living (EHL) Wales cohort study.

BACKGROUND: Health is a result of influences operating at multiple levels. For example, inadequate housing, poor educational attainment, and reduced access to health care are clustered together, and are all associated with reduced health. Policies which try to change individual people's behaviour have limited effect when people have little control over their environment. However, structural environmental change and an understanding of the way that influences interact with each other, has the potential to facilitate healthy choices irrespective of personal resources. The aim of Environments for Healthy Living (EHL) is to investigate the impact of gestational and postnatal environments on health, and to examine where structural change can be brought about to optimise health outcomes. The baseline assessment will focus on birth outcomes and maternal and infant health. METHODS/DESIGN: EHL is a longitudinal birth cohort study. We aim to recruit 1000 pregnant women in the period April 2010 to March 2013. We will examine the impact of the gestational environment (maternal health) and the postnatal environment (housing and neighbourhood conditions) on subsequent health outcomes for the infants born to these women. Data collection will commence during the participants' pregnancy, from approximately 20 weeks gestation. Participants will complete a questionnaire, undergo anthropometric measurements, wear an accelerometer, compile a food diary, and have environmental measures taken within their home. They will also be asked to consent to having a sample of umbilical cord blood taken following delivery of their baby. These data will be complemented by routinely collected electronic data such as health records from GP surgeries, hospital admissions, and child health and development records. Thereafter, participants will be visited annually for follow-up of subsequent exposures and child health outcomes. DISCUSSION: The baseline assessment of EHL will provide information concerning the impact of gestational and postnatal environments on birth outcomes and maternal and infant health. The findings can be used to inform the development of complex interventions targeted at structural, environmental factors, intended to reduce ill-health. Long-term follow-up of the cohort will focus on relationships between environmental exposures and the later development of adverse health outcomes, including obesity and diabetes.

The influence of a high intensity physical activity intervention on a selection of health related outcomes: an ecological approach.

BACKGROUND: Cardiovascular disease (CVD) is the main cause of mortality throughout the world. With accumulating evidence suggesting that CVD has its origins in childhood, it is unsurprising that research into obesity prevalence within school aged youth is burgeoning. Within this study our primary objective will be to examine whether high intensity interval training (HIT) improves the CVD risk profile of secondary school aged adolescents. Our secondary objective will be to identify the prevalence of CVD risk factors and examine factors associated with these in adolescents aged 15-18 years. METHOD/DESIGN: A South Lanarkshire school of low socioeconomic status (SES) was selected to participate in the study intervention. Participants from secondary 5 (15-17 years) and 6 (16-18 years) will be recruited for this study. Participants from secondary 6 will be randomly assigned to Group A (HIT) or Group B (moderate-vigorous) and will perform each protocol three times weekly. The secondary 5 participants will act as the control group. Data collection will take place during the Physical Education (PE) lessons and on school premises and will include: anthropometrical variables (height, weight, waist and hip circumferences, skinfold thickness at two sites), physiological responses (blood pressure, aerobic fitness, heart rate (HR) response, vertical jump performance, 10-metre (m) sprint, 50-m sprint and 505-agility test), diet (self-reported seven-day food diary), physical activity (Physical Activity Questionnaire for Adolescents (PAQ-A)) and blood tests (fasting glucose, insulin, total cholesterol (TC), high-density lipoprotein (HDL), high-sensitivity C-reactive protein (hs-CRP), fibrinogen (Fg), interleukin-6 (IL-6), adiponectin (high molecular weight), triglyceride and plasminogen activator inhibitor-1 (PAI-1). An environmental audit of the secondary school and the health related quality of life (HRQOL) of the participants will also be measured. Finally, all exercise sessions will be video recorded and rate of perceived exertion (RPE) and mood states will also be taken after each exercise session. DISCUSSION: Our study may be able to demonstrate a time efficient means of reducing CVD risk factors in adolescents. TRIAL REGISTRATION: NCT01027156.

Risk factors for childhood obesity at age 5: analysis of the millennium cohort study.

BACKGROUND: Weight at age 5 is a predictor for future health of the individual. This study examines risk factors for childhood obesity with a focus on ethnicity. METHODS: Data from the Millennium Cohort study were used. 17,561 singleton children of White/European (n = 15,062), Asian (n = 1,845) or African (n = 654) background were selected. Logistic regression and likelihood ratio tests were used to examine factors associated with obesity at age 5. All participants were interviewed in their own homes. The main exposures examined included; Birth weight, sedentary lifestyle, family health behaviours, ethnicity, education and income. RESULTS: Children with a sedentary lifestyle, large at birth, with high risk family health behaviours (overweight mothers, smoking near the child, missing breakfast) and from a family with low income or low educational attainment, were more likely to be obese regardless of ethnicity. Feeding solid food before 3 months was associated with obesity in higher income White/European families. Even when controlling for socioeconomic status, ethnic background is an important independent risk factor for childhood obesity [Odds ratio of obesity; was 1.7 (95%CI: 1.2-2.3) for Asian and 2.7 (95%CI: 1.9-3.9) for African children, compared to White/European]. The final adjusted model suggests that increasing income does not have a great impact on lowering obesity levels, but that higher academic qualifications are associated with lower obesity levels [Odds of obesity: 0.63 (95%CI: 0.52-0.77) if primary carer leaves school after age 16 compared at age 16]. CONCLUSIONS: Education of the primary carer is an important modifiable factor which can be targeted to address rising obesity levels in children. Interventions should be family centred supporting and showing people how they can implement lifestyle changes in their family.

A cross-curricular physical activity intervention to combat cardiovascular disease risk factors in 11-14 year olds: 'activity knowledge circuit'.

BACKGROUND: Cardiovascular disease is the leading cause of mortality worldwide. Risk factors associated with cardiovascular disease have been shown to track from childhood through to adulthood. Previous school-based physical activity interventions have demonstrated modest improvements to cardiovascular disease risk factors by implementing extra-curricular activities or improving current physical education curriculum. Few have attempted to increase physical activity in class-room taught curriculum subjects. This study will outline a school-based cross-curricular physical activity intervention to combat cardiovascular disease risk factors in 11-14 year old children. METHOD/DESIGN: A South Wales Valley school of low socio-economic status has been selected to take part. Participants from year eight (12-13 years) are to be assigned to an intervention group, with maturation-matched participants from years seven (11-12 years) and nine (13-14 years) assigned to a control group. A cross-curricular physical activity intervention will be implemented to increase activity by two hours a week for 18 weeks. Participants will briskly walk 3200 m twice weekly during curriculum lessons (60 minutes duration). With the exception of physical education, all curriculum subjects will participate, with each subject delivering four intervention lessons. The intervention will be performed outdoors and on school premises. An indoor course of equal distance will be used during adverse weather conditions. Cardiovascular disease risk factors will be measured pre- and post-intervention for intervention and control groups. These will take place during physical education lessons and will include measures of stature, mass, waist, hip, and neck circumferences, together with skinfold measure's taken at four sites. Blood pressure will be measured, and fitness status assessed via the 20 m multi-stage fitness test. Questionnaires will be used to determine activity behaviour (physical activity questionnaire for adolescence), diet (seven day food diary) and maturation status. Fasting blood variables will include total cholesterol, low-density lipoprotein cholesterol, high density lipoprotein cholesterol, triglycerides, insulin, glucose, high-sensitivity C-reactive protein, interleukin-6, adiponectin, and fibrinogen. Motivational variables and psychological well-being will be assessed by questionnaire. DISCUSSION: Our study may prove to be a cost effective strategy to increase school time physical activity to combat cardiovascular disease risk factors in children. TRIAL REGISTRATION: [NCT00998478].

Changes in endothelial dysfunction and associated cardiovascular disease morbidity markers in GH-IGF axis pathology.

Arterial endothelial dysfunction is an early event in the pathogenesis of atherosclerosis and predisposes individuals to the deposition of unstable atherosclerotic plaques. It can also lead to increased arterial stiffness, which is an accepted cause of increased arterial pulse wave velocity (APWV). Endothelial dysfunction is reversed by recombinant human growth hormone (rhGH) therapy in patients with growth hormone (GH) deficiency (GHD), favorably influencing the risk for atherogenesis. Endogenous human growth hormone (hGH), secreted by the anterior pituitary, and levels of insulin-like growth factor-I (IGF-I), produced in response to hGH stimulation of the liver, peak during early adulthood, but decline throughout adulthood. It is suspected that low-grade inflammatory cardiovascular pathophysiologic markers such as homocysteine, nitric oxide, C-reactive protein (CRP), and fibrinogen and plasminogen activator inhibitor along with changes in lipid and glucose metabolism may all contribute to GHD-associated metabolic and cardiovascular complications. These effects are associated with increased APWV, but are attenuated by rhGH therapy in GHD. GH replacement increases IGF-I levels and reduces CRP and large-artery stiffness. Reviews of rhGH in the somatopause have not been overtly favorable. Whereas reviews of rhGH/rhIGF-I combinations in GH resistance are more positive than those for rhGH alone, their combined use in the somatopause is limited. Senescent individuals may benefit from such a combination.