Association between common variation at the FTO locus and changes in body mass index from infancy to late childhood: the complex nature of genetic association through growth and development.

An age-dependent association between variation at the FTO locus and BMI in children has been suggested. We meta-analyzed associations between the FTO locus (rs9939609) and BMI in samples, aged from early infancy to 13 years, from 8 cohorts of European ancestry. We found a positive association between additional minor (A) alleles and BMI from 5.5 years onwards, but an inverse association below age 2.5 years. Modelling median BMI curves for each genotype using the LMS method, we found that carriers of minor alleles showed lower BMI in infancy, earlier adiposity rebound (AR), and higher BMI later in childhood. Differences by allele were consistent with two independent processes: earlier AR equivalent to accelerating developmental age by 2.37% (95% CI 1.87, 2.87, p = 10(-20)) per A allele and a positive age by genotype interaction such that BMI increased faster with age (p = 10(-23)). We also fitted a linear mixed effects model to relate genotype to the BMI curve inflection points adiposity peak (AP) in infancy and AR. Carriage of two minor alleles at rs9939609 was associated with lower BMI at AP (-0.40% (95% CI: -0.74, -0.06), p = 0.02), higher BMI at AR (0.93% (95% CI: 0.22, 1.64), p = 0.01), and earlier AR (-4.72% (-5.81, -3.63), p = 10(-17)), supporting cross-sectional results. Overall, we confirm the expected association between variation at rs9939609 and BMI in childhood, but only after an inverse association between the same variant and BMI in infancy. Patterns are consistent with a shift on the developmental scale, which is reflected in association with the timing of AR rather than just a global increase in BMI. Results provide important information about longitudinal gene effects and about the role of FTO in adiposity. The associated shifts in developmental timing have clinical importance with respect to known relationships between AR and both later-life BMI and metabolic disease risk.

Lifestyle and demographic correlates of poor mental health in early adolescence.

AIM: To determine the constellation of lifestyle and demographic factors that are associated with poor mental health in an adolescent population. METHODS: The Raine Study 14-year follow-up involved primary care givers and their adolescent children (n= 1860). The Child Behaviour Checklist (CBCL) was used to assess adolescent mental health. We examined diet, socio-demographic data, family functioning, physical activity, screen use and risk-taking behaviours with mental health outcomes using linear regression. RESULTS: Adolescents with higher intakes of meat and meat alternatives and 'extras' foods had poorer mental health status. Adverse socio-economic conditions, higher hours of screen use and ever partaking in the health risk behaviours of smoking and early sexual activity were significantly associated with increasing CBCL scores, indicative of poorer functioning. CONCLUSIONS: By identifying the lifestyle and demographic factors that accompany poorer mental health in early adolescence, we are able to better understand the context of mental health problems as they occur within an adolescent population.

Impact of the 2017 American Heart Association and American College of Cardiology hypertension guideline in aged individuals.

OBJECTIVES: The AHA/ACC-2017 hypertension guideline recommends an age-independent target blood pressure (BP) of less than 130/80 mmHg. In an elderly cohort without established cardiovascular disease (CVD) at baseline, we determined the impact of this guideline on the prevalence of hypertension and associated CVD risk. METHODS: Nineteen thousand, one hundred and fourteen participants aged at least 65 years from the ASPirin in Reducing Events in the Elderly (ASPREE) study were grouped by baseline BP: 'pre-2017 hypertensive' (BP ≥140/90 mmHg and/or on antihypertensive drugs); 'reclassified hypertensive' (normotensive by pre-2017 guidelines; hypertensive by AHA/ACC-2017 guideline), and 'normotensive' (BP <130 and <80 mmHg). For each group, we evaluated CVD risk factors, predicted 10-year CVD risk using the Atherosclerotic Cardiovascular Disease (ASCVD) risk equation, and reported observed CVD event rates during a median 4.7-year follow-up. RESULTS: Overall, 74.4% (14 213/19 114) were 'pre-2017 hypertensive'; an additional 12.3% (2354/19 114) were 'reclassified hypertensive' by the AHA/ACC-2017 guideline. Of those 'reclassified hypertensive', the majority (94.5%) met criteria for antihypertensive treatment although 29% had no other traditional CVD risk factors other than age. Further, a relatively lower mean 10-year predicted CVD risk (18% versus 26%, P < 0.001) and lower CVD rates (8.9 versus 12.1/1000 person-years, P = 0.01) were observed in 'reclassified hypertensive' compared with 'pre-2017 hypertensive'. Compared with 'normotensive', a hazard ratio (95% confidence interval) for CVD events of 1.60 (1.26-2.02) for 'pre-2017 hypertensive' and 1.26 (0.93-1.71) for 'reclassified hypertensive' was observed. CONCLUSION: Applying current CVD risk calculators in the elderly 'reclassified hypertensive', as a result of shifting the BP threshold lower, increases eligibility for antihypertensive treatment but documented CVD rates remain lower than hypertensive patients defined by pre2017 BP thresholds.

Long-term follow-up of participants in a health promotion program for treated hypertensives (ADAPT).

BACKGROUND AND AIMS: Improvements in a lifestyle modification program for hypertensives were maintained 1 year later. Longer follow-up in such studies is limited; we therefore re-assessed participants after an additional 2 years in which there was no contact with program facilitators. METHODS AND RESULTS: Participants randomised to usual care (N=118) or a 4-month lifestyle program (N=123) were previously assessed after 4 months and 1 year. After a further 2 years, diet, alcohol intake, physical activity, weight, waist girth, ambulatory blood pressure (BP), blood lipids, glucose and insulin were measured (usual care N=64; program N=76). Statistically significant net changes, relative to usual care, included blood cholesterol (-0.2 mmol/L, 95% CI 0.1-0.4); physical activity (53 min/week, 95% CI 15-91); dietary saturated fat (-1.9% energy, 95% CI -0.1 to -3.8); fish (3.2 serves/month, 95% CI 0.7-5.7); vegetables (9.1 serves/month, 95% CI 3.2-15.1); and sweet foods (-6.2 serves/month, 95% CI -1.1 to -11.3). Between-group changes in weight (-0.7 kg, 95% CI -1.8-0.4), BP (systolic 1.4 mmHg, 95% CI -0.7-3.5)/diastolic 1.0 mmHg, 95% CI -0.3-2.4) and Framingham risk (usual care: men 12.1%, women 3.7%; program: men 12.2%; women 3.5%) did not differ significantly. CONCLUSION: Continued reinforcement with long-term follow-up is needed in lifestyle modification programs.

A lifestyle program for treated hypertensives improved health-related behaviors and cardiovascular risk factors, a randomized controlled trial.

OBJECTIVE: To assess effects of a cognitively based program on health-related behaviors and cardiovascular risk factors in overweight drug-treated hypertensives. STUDY DESIGN AND SETTING: In a clinical trials center, volunteers, recruited by advertisement, were randomized to usual care (N=118) or to a 4-month program (N=123) incorporating weight loss; a low-sodium diet, high in fruit, vegetables, and fish; and increased physical activity. Diet, physical activity, weight, blood lipids, glucose, and insulin were measured at 4 and 16 months. RESULTS: Ninety-eight usual care and 106 program participants completed the 4-month assessment; 90 and 102, respectively, completed follow-up. Using intention-to-treat analysis, relative to usual care, net changes with the program at 4 months were as follows: dietary fat (-2.6% energy; P<0.001); sodium (-290mg/d; P=0.004); energy (-313mJ/d; P=0.005); fish (+2.1 serves/wk; P<0.001); vegetables (+3.0 serves/wk; P<0.001); physical activity (+37min/wk; P=0.004); weight (-2.8kg; P<0.001); waist girth (-3.1cm; P<0.001); total cholesterol (-0.2mmol/L; P=0.017); and triacylglycerols (-0.12mmol/L; P=0.002). One year later, net changes included dietary fat (-2.2% energy; P<0.001); sodium (-150mg/d; P=0.029); fish (+2.0 serves/wk; P<0.001); vegetables (+4.3 serves/wk; P<0.001); weight (-2.5kg; P=0.001); waist girth (-3.1cm; P<0.001); high-density lipoprotein cholesterol (+0.03mmol/L; P=0.031). CONCLUSION: Improvements in behaviors and risk factors, several maintained long term, suggest the potential for long-term benefits in hypertensives.

Urinary 20-hydroxyeicosatetraenoic acid is associated with endothelial dysfunction in humans.

BACKGROUND: 20-hydroxyeicosatetraenoic acid (20-HETE) is a cytochrome P450 (omega-hydroxylase) metabolite of arachidonic acid with vasoconstrictor activity that may be involved in the pathogenesis of hypertension. In humans, there are few data relating 20-HETE to vascular pathophysiology. This study aimed to determine whether urinary 20-HETE excretion is related to blood pressure or vascular endothelial function in humans. METHODS AND RESULTS: Sixty-six subjects (37 males, 29 females), including 29 with untreated hypertension, had urinary 20-HETE excretion measured by gas chromatography/mass spectrometry. There was no significant difference for 20-HETE excretion between hypertensive and normotensive subjects. 20-HETE excretion was positively related to body mass index and sodium excretion. There was a significant inverse association between urinary 20-HETE and endothelium-dependent vasodilation measured by flow-mediated dilation of the brachial artery (P=0.006). There was no association with vasodilator responses to nitroglycerin. In multiple regression analysis, 20-HETE remained an independent predictor of endothelium-dependent vasodilation after adjustment for age, body mass index, and blood pressure. When gender was included in the model, the relationship between 20-HETE and flow-mediated dilation was attenuated. Separate analysis by gender revealed that in women, hypertensive subjects had significantly higher 20-HETE excretion than normotensive subjects, but this was not seen in men. In women, 20-HETE was positively related to diastolic and systolic blood pressure. In men, 20-HETE was positively related to body mass index. CONCLUSIONS: This is the first demonstration of an association between 20-HETE excretion and in vivo vascular function in humans. Given the negative modulatory role of nitric oxide on omega-hydroxylase, the present results suggest a potentially important role for 20-HETE in human vascular physiology.

Effects of a lifestyle programme on ambulatory blood pressure and drug dosage in treated hypertensive patients: a randomized controlled trial.

OBJECTIVE: To assess effects of multifactorial lifestyle modification on antihypertensive drug needs in treated hypertensive individuals. DESIGN: Randomized controlled trial. SETTING: Research studies unit. PARTICIPANTS: Overweight hypertensive patients, receiving one or two antihypertensive drugs, were recruited by advertising, and allocated randomly to a usual care group (controls; n = 118) or a lifestyle modification group (programme group; n = 123). INTERVENTION: A 4-month programme of weight loss, a low-sodium 'Dietary Approaches to Stop Hypertension'-type diet with added fish, physical activity and moderation of alcohol intake. After 4 months, if mean 24-h ambulatory blood pressure (ABP) was less than 135/85 mmHg, antihypertensive drugs were withdrawn over 4 weeks and long-term home blood pressure monitoring was begun. MAIN OUTCOME MEASURES: Antihypertensive drug requirements, ABP, weight, waist girth at 4 months and 1-year follow-up. RESULTS: Ninety control group and 102 programme group participants completed the study. Mean 24-h ABP changed after 4 months by -1.0/-0.3 +/- 0.5/0.4 mmHg in controls and -4.1/-2.1 +/- 0.7/0.5 mmHg with the lifestyle programme (P < 0.01). At follow-up, changes in the two groups were not significantly different (4.1/1.3 +/- 1.1/1.0 mmHg in controls; 2.5/-0.1 +/- 1.1/0.8 mmHg in the programme group; P = 0.73). At 4 months, drug withdrawal differed significantly between the groups (P = 0.038) in men (control 44%; programme 66%) but not in women (65 and 64%, respectively; P = 0.964). At follow-up, sex-related differences were not significant, and 41% in the control group and 43% in the programme group maintained drug-withdrawal status. With the programme, net weight loss was 3.3 kg (P < 0.001) at 4 months and 3.0 kg (P < 0.001) at follow-up; respective net decreases in waist girth were 3.3 cm (P < 0.001) and 3.5 cm (P < 0.001). CONCLUSIONS: A 4-month multifactorial lifestyle modification in patients with treated hypertension reduced blood pressure in the short-term. Decreased central obesity persisted 1 year later and could reduce overall cardiovascular risk.

Accuracy of blood pressure measurement and anthropometry among volunteer observers in a large community survey.

The Busselton Survey is a population survey that is held about every three years. In 1994-1995 a re-survey was held of all past participants and 8,502 attended. Financial constraints precluded employing staff for data collection for blood pressure and anthropometry, these therefore were collected by unpaid lay volunteers. Quality control by a health professional was critical to the assessment and maintenance of accuracy in these measurements. For blood pressure three readings were taken simultaneously by a quality control person and the volunteer using a dual stethoscope. Duplicate anthropometric measurements were taken by a criterion anthropometrist and the volunteer. Inter and intra-observer technical errors of measurement (TEM) were calculated. Sixty-two volunteers were trained to take BP measurements; of these, 38 collected data, and 63 were trained in anthropometry; of these, 30 were suitable as measurers. Training was conducted on a group and individual basis by the quality assurance person for the study both in the Perth metropolitan area and rural Busselton. The TEM for SBP was 1.6 mm Hg (SD 1.0 mm Hg) and 1.5 mm Hg (SD 0.8) for DBP. For skin-folds intra-observer TEM ranged from 0.6 mm to 1.0 mm. Between-observer TEM ranged from 2.1 mm to 5.4 mm. For limb and waist circumferences, intra-observer TEM ranged from 0.3 cm to 1.6 cm. Between-observer TEM for circumferences ranged from 0.5 cm to 1.9 cm. Unpaid volunteer measurers can, if carefully trained and supervised, provide acceptable blood pressure data and anthropometry in large population surveys.

Physical activity and nutrition programs for couples: a randomized controlled trial.

Diet and physical activity habits may deteriorate after cohabitation, leading to weight gain and increased risk of lifestyle diseases. We carried out a 4-month, randomized controlled trial of a diet and physical activity program for couples with a 1-year follow-up, comparing two methods of delivery. The program used six modules, which, after an initial group session, were mailed to the low-level intervention group. In the high-level intervention group, half of the modules were mailed, and the others were delivered at interactive group sessions. A control group received no intervention. Postintervention and at follow-up, physical fitness improved in the high-level group, saturated fat intake decreased in both intervention groups, and low-density lipoprotein cholesterol fell in the high-level group. Fewer participants in the high-level group became overweight or obese. Health promotion for couples can improve health behaviors and potentially lower the risk of lifestyle diseases in participants and their future families.

The independent and combined effects of 16 weeks of vigorous exercise and energy restriction on body mass and composition in free-living overweight men--a randomized controlled trial.

This study assessed the effects of 16 weeks of energy restriction and vigorous exercise on body mass and body composition. Sixty sedentary men, mean body mass (mean +/- SD) 96.3 (13.9) kg and mean age 42.4 (5.0) years, were randomly assigned to either continue their normal energy intake or restrict energy intake by 4,186 to 6,279 kJ. d(-1). Each group was further randomized to a control light exercise program, or a vigorous exercise program for 3 half-hour sessions per week. Vigorous exercise improved maximum oxygen consumption (Vo(2max)) by approximately 24% (0.56 [95% confidence interval, 0.47 to 0.65) L. min(-1), P <.001) with no significant changes in body mass, body composition, or fat distribution. With energy restriction there was a significant reduction in body mass of 10.1 (8.0 to 12.2) kg, lean body mass (LBM) of 2.4 (1.5 to 3.3) kg, fat mass (FM) of 7.7 (5.9 to 9.6) kg, waist to hip ratio (WHR) of 0.03 (0.01 to 0.04), and the sum of 6 skinfolds of 26.9 (15.4 to 38.4) mm (P <.001). Combining vigorous exercise with energy restriction resulted in no further changes in measures of body composition. We conclude that in sedentary free-living overweight men, 16 weeks of energy restriction, but not vigorous intensity exercise, results in substantial reductions in body mass, LBM, and FM. Furthermore, vigorous intensity exercise when combined with energy restriction did not modify or enhance the changes in body fat distribution or body composition seen with energy restriction alone. The independent effects of exercise to induce changes in body mass and composition in the longer term in free-living overweight subjects on an energy-restricted diet deserve further study.

Changes in cognitive measures in a randomized controlled trial of a health promotion program for couples targeting diet and physical activity.

PURPOSE: To examine cognitive responses to a 4-month health promotion program targeting diet and physical activity in recently cohabiting couples. DESIGN: A three-group randomized controlled trial: no intervention (Controls), interactive group sessions and mail-outs (Interactive), and one group session followed by mail-outs (Mail). SETTING: Australian research studies unit. SUBJECTS: Seventy-eight of 137 couples cohabiting for < 2 years, recruited by advertising, completed the study. MEASURES: Stages of change; health beliefs; self-efficacy; and perceived barriers to change evaluated by questionnaires at baseline, postintervention, and 1-year follow-up. Data were analyzed using mixed models, factor analysis, and linear regression. RESULTS: In the Mail group, the perceived importance of barriers to dietary change decreased by 19% at postintervention and 16% at 1-year follow-up; dietary self-efficacy increased by 9% and 3%, respectively. In the Interactive group, the perceived importance of barriers to dietary change decreased by 26% and 20%, and dietary self-efficacy increased by 14% and 12%, respectively. Similar trends for physical activity were not statistically significant. However, changes in self-efficacy and perceived barriers to change significantly predicted dietary and physical activity behaviors. A preponderance of higher socio-economic groups and the proportion of drop-out may have biased results. CONCLUSIONS: Health promotion using partners' support and targeting diet and physical activity improves associated cognitive variables in couples. Most improvements were greater and more sustained with interactive group sessions.

Genetic influences on trajectories of systolic blood pressure across childhood and adolescence.

BACKGROUND: Blood pressure (BP) tends to increase across childhood and adolescence, but the genetic influences on rates of BP change are not known. Potentially important genetic influences could include genetic variants identified in genome-wide association studies of adults as being associated with BP, height, and body mass index. Understanding the contribution of these genetic variants to changes in BP across childhood and adolescence could yield understanding into the life course development of cardiovascular risk. METHODS AND RESULTS: Pooling data from 2 cohorts (the Avon Longitudinal Study of Parents and Children [n=7013] and the Western Australian Pregnancy Cohort [n=1459]), we examined the associations of allelic scores of 29 single-nucleotide polymorphisms (SNPs) for adult BP, 180 height SNPs, and 32 body mass index SNPs, with trajectories of systolic BP (SBP) from 6 to 17 years of age, using linear spline multilevel models. The allelic scores of BP and body mass index SNPs were associated with SBP at 6 years of age (per-allele effect sizes, 0.097 mm Hg [SE, 0.039 mm Hg] and 0.107 mm Hg [SE, 0.037 mm Hg]); associations with age-related changes in SBP between 6 and 17 years of age were of small magnitude and imprecisely estimated. The allelic score of height SNPs was only weakly associated with SBP changes. No sex or cohort differences in genetic effects were observed. CONCLUSIONS: Allelic scores of BP and body mass index SNPs demonstrated associations with SBP at 6 years of age with a similar magnitude but were not strongly associated with changes in SBP with age between 6 and 17 years. Further work is required to identify variants associated with changes with age in BP.

Omega-3 Index correlates with healthier food consumption in adolescents and with reduced cardiovascular disease risk factors in adolescent boys.

The Omega-3 Index, a measure of long-chain omega-3 fats in red blood cell membranes, predicts heart disease mortality in adults, but its association with cardiovascular risk factors in younger populations is unknown. We determined the Omega-3 Index in adolescents participating in the Western Australian Pregnancy (Raine) Cohort, assessed associations with diet, lifestyle and socioeconomic factors, and investigated independent associations with cardiovascular and metabolic risk factors. Red blood cell fatty acid analysis was determined for 1,301 adolescents aged 13-15 years. Risk factors examined were blood pressure, fasting blood insulin and glucose concentrations, and fasting blood lipids including ratios. The mean Omega-3 Index was 4.90 ± 1.04% (range 1.41-8.42%). When compared with categories identified in adults, 15.6% of adolescents were in the high risk category (Index < 4%). Age (P < 0.01), maternal education (P < 0.01) and BMI (P = 0.05) were positively associated with the Omega-3 Index. The Index was positively associated with dietary intakes of eicosapentaenoic and docosahexaenoic acid (P < 0.01), protein (P < 0.01), omega-3 fats (P < 0.04), and food groups of fish and wholegrains (both P < 0.01), and negatively associated with intakes of soft drinks and crisps (both P < 0.01). In boys, the Omega-3 Index was independently associated with total (ß = 0.06, P = 0.01) and HDL-cholesterol (ß = 0.03, P = 0.01), and diastolic blood pressure (ß = -0.68, P = 0.04). The predictability of the Index for the risk of cardiovascular disease later in life warrants further investigation in the adolescent population.

Dietary intake and food sources of fatty acids in Australian adolescents.

BACKGROUND: Dietary fat consumed during childhood and adolescence may be related to the development of cardiovascular and other chronic diseases in adulthood; however, there is a lack of information on specific fatty acid intakes and food sources in these populations. Our study aimed to assess fatty acid intakes in Australian adolescents, compare intakes with national guidelines, and identify major food sources of fatty acids. METHODS: Dietary intake was assessed using measured 3-d records in 822 adolescents aged 13-15 y participating in The Western Australian Pregnancy Cohort (Raine) Study, Australia. RESULTS: Mean daily total fat intakes were 90 ± 25 g for boys and 73 ± 20 g for girls, with saturated fat contributing 14% of total energy intake. Mean contribution to daily energy intake for linoleic, alpha-linolenic, eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids were 3.0%, 0.40%, 0.02%, 0.01%, and 0.04%, respectively, for boys, and 3.3%, 0.42%, 0.02%, 0.01%, and 0.05% for girls. To meet guidelines for chronic disease prevention, consumption of long-chain omega-3 fatty acids in this population may need to increase up to three-fold and the proportion of saturated fat decrease by one-third. Girls were more likely to achieve the guidelines. Major food sources were dairy products for total fat, saturated fat and alpha-linolenic acid, margarines for linoleic acid, and fish for long-chain omega-3 fatty acids. CONCLUSION: Results suggest that for this population, a higher dietary intake of long-chain omega-3 fatty acids, particularly for boys, and lower proportion of saturated fat is required to meet recommendations for prevention of chronic disease.

Variants near CCNL1/LEKR1 and in ADCY5 and fetal growth characteristics in different trimesters.

CONTEXT: A recent genome-wide association study identified variants near CCNL1/LEKR1 (rs900400) and in ADCY5 (rs9883204) to be associated with birth weight. We examined the associations of these variants with fetal growth characteristics in different trimesters, with a main interest in the timing of the associations and the affected body proportions. METHODS: We used data from two prospective cohort studies from fetal life onward in The Netherlands and Australia. Repeated fetal ultrasound examinations were performed to measure head circumference (HC), abdominal circumference (AC), femur length (FL), and estimated fetal weight (EFW). Analyses were based on a total group of 3909 subjects. RESULTS: The C-allele of rs900400 was associated in second trimester with smaller fetal HC and FL, and in third trimester with smaller HC, AC, FL, and EFW. For each C-allele, the combined effect estimate for EFW in third trimester was -18.6 g (95% confidence interval, -27.5, -9.7 g; P = 4.2 × 10(-5)). The C-allele of rs9883204 was not associated with fetal growth characteristics in second trimester but was associated with restriction of all growth characteristics, except HC, in third trimester and at birth. For each C-allele, the combined effect estimate was -16.9 g (95% confidence interval, -26.8, -7.0 g; P = 8.4 × 10(-4)) for EFW in third trimester. Both genetic variants were associated with lower birth and placenta weight. CONCLUSIONS: Our results suggest that a genetic variant of rs900400 leads to symmetric growth restriction from early pregnancy onward, whereas a genetic variant of rs9883204 leads to asymmetric growth restriction, characterized by a relatively larger HC, from third trimester.

Moderators and mediators of behaviour change in a lifestyle program for treated hypertensives: a randomized controlled trial (ADAPT).

We aimed to examine moderators and mediators of behaviour change in a cognitive lifestyle program for drug-treated overweight hypertensives in Perth, Australia. We collected data at baseline, 4 months (post-intervention) and 1-year follow-up in a randomized controlled trial of a program that focused on weight loss, diet, and exercise. Mediation analysis used regression models that estimate indirect effects with bootstrapped confidence limits. Outcomes examined were saturated fat intake (% energy) and physical activity (hours per week). In total, 90/118 individuals randomized to usual care and 102/123 to the program-completed follow-up. Sex was a moderator of response post-intervention for diet and physical activity, with a greater response among women with usual care and among men with the program. Change in self-efficacy was a mediator of dietary change post-intervention [effect size (ES) -0.055, 95% confidence interval (CI) -0.125, -0.005] and at follow-up (ES 0.054, 95% CI -0.127, -0.005), and in physical activity post-intervention (ES 0.059, 95% CI 0.003, 0.147). These findings highlight different responses of men and women to the program, and the importance of self-efficacy as a mediator. Mediators for physical activity in the longer term should be investigated in other models, with appropriate cognitive measurements, in future trials.

Chocolate craving among children: implications for disordered eating patterns.

The aim was to test the validity of a multidimensional model of chocolate craving among children, and to examine if the dimensions underlying the model predict consumption and eating disordered symptoms. Participants were 602 children (53% female) aged 11, 12, and 13 from 11 schools in Western Australia. Measures included the Orientation to Chocolate Questionnaire (OCQ) designed to assess three components of chocolate craving (approach, avoidance, and guilt), questions assessing body image dissatisfaction and dieting, and body mass index (BMI). Using structural equation modeling, results confirmed that chocolate craving among children is best conceptualized as a three-factor model (approach, avoidance, guilt). The underlying dimensions were differentially associated with self-reported chocolate consumption and indicators of disordered eating patterns. After controlling for BMI and gender, chocolate-related guilt was strongly associated with greater body dissatisfaction and dieting, and avoidance inclinations were also associated with dieting. Chocolate-related guilt was higher in girls than in boys. Results suggest that children experience chocolate craving as a multidimensional phenomenon reflecting some ambivalence. A gender difference in chocolate-related guilt appears to emerge in childhood, potentially contributing to a greater risk for girls to develop exaggerated concerns about body shape and weight.

Predictors of type 2 diabetes and diabetes-related hospitalisation in an Australian Aboriginal cohort.

Predictors of diabetes and diabetes-related hospitalisations were examined in 15-88-year-old Aboriginal Australians (256 women, 258 men), surveyed in 1988-1989. Linkage to death records and hospitalisations to 2002 allowed proportional hazards or negative binomial modelling. Forty-five men (18%) and 59 women (24%) developed diabetes. Risk of diabetes was predicted positively by waist girth (hazard ratio (HR) 1.08, 95% CI 1.04, 1.13), smoking (HR 2.05, 95% CI 1.23, 3.39) and eating processed meats>4 times/month (HR 1.58, 95% CI 1.05, 2.40) and negatively by lower alcohol intake (HR 0.69, 95% CI 0.49, 0.99), preferring wine (HR 0.13, 95% CI 0.02, 0.97) and eating bush meats>4 times/month (HR 0.34, 95% CI 0.13, 0.90). Hospitalisation was predicted positively by smoking (Incidence rate ratio (IRR) 3.72, 95% CI 1.70, 8.18) and eating processed meats (IRR 1.03, 95% CI 1.01, 1.06), and negatively by exercise>or=once/week (IRR 0.23, 95% CI 0.08, 0.65), eating bush meats (IRR 0.95, 95% CI 0.91, 0.99) and trimming fat from meats (IRR 0.53, 95% CI 0.30, 0.94). Length of hospital stay was predicted positively by eating processed meats (HR 1.76, 95% CI 1.23, 2.53) and added salt (HR 1.52, 95% CI 1.02, 2.26) and negatively by lower alcohol intake (HR 0.90, 95% CI 0.40, 0.92) and exercise (HR 0.66, 95% CI 0.46, 0.95). Central obesity and adverse lifestyle increase risk for diabetes or related hospitalisation among Aboriginal Australians.

Television, computer use, physical activity, diet and fatness in Australian adolescents.

PURPOSE: To examine sedentary behaviours (including television viewing, playing computer games and computer use), diet, exercise and fitness in relation to overweight/obesity in Australian adolescents. METHODS: Questionnaires elicited food frequency data, time spent in TV-viewing, using computers, other sedentary occupations and physical activity recall. Weight, height and fitness (laps completed in the Leger test) were measured. RESULTS: Among 281 boys and 321 girls, mean age 12 years (SD 0.9), 56 boys (20.0%) and 70 girls (23.3%) were overweight/obese. Greater fitness was associated with decreased risk of overweight/obesity in boys (Odds ratio [OR] 0.74; 95% CI 0.55, 0.99) and girls (OR 0.93; 95% CI 0.91, 0.99). TV-viewing predicted increased risk in boys (OR 1.04; 95% CI 1.01, 1.06) and decreased risk in girls (OR 0.99; 95% CI 0.96, 0.99). Computer use, video games, and other sedentary behaviours were not significantly related to risk of overweight/obesity. Vegetable intake was associated with lower risk in boys (OR 0.98; 95% CI 0.97, 0.99); greater risk was associated with lower fat intake in boys and girls, lower consumption of energy-dense snacks in boys (OR 0.74; 95% CI 0.62, 0.88) and greater intake of vegetables in girls (OR 1.02; 95% CI 1.00, 1.03), suggesting dieting or knowledge of favourable dietary choices in overweight/obese children. CONCLUSIONS: Among these adolescents, fitness was negatively related to risk for overweight/obesity in boys and girls. TV-viewing was a positive predictor in boys and a negative predictor in girls but the effect size was small; other sedentary behaviours did not predict risk.