Central obesity as a precursor to the metabolic syndrome in the AusDiab study and Mauritius

Evidence from epidemiologic studies that central obesity precedes future metabolic change and does not occur concurrently with the appearance of the blood pressure, glucose, and lipid abnormalities that characterize the metabolic syndrome (MetS) has been lacking. Longitudinal surveys were conducted in Mauritius in 1987, 1992, and 1998, and in Australia in 2000 and 2005 (AusDiab). This analysis included men and women (aged 25 years) in three cohorts: AusDiab 2000–2005 (n = 5,039), Mauritius 1987–1992 (n = 2,849), and Mauritius 1987–1998 (n = 1,999). MetS components included waist circumference, systolic blood pressure, fasting and 2-h postload plasma glucose, high-density lipoprotein (HDL) cholesterol, triglycerides, and homeostasis model assessment of insulin sensitivity (HOMA-S) (representing insulin sensitivity). Linear regression was used to determine which baseline components predicted deterioration in other MetS components over 5 years in AusDiab and 5 and 11 years in Mauritius, adjusted for age, sex, and ethnic group. Baseline waist circumference predicted deterioration (P < 0.01) in four of the other six MetS variables tested in AusDiab, five of six in Mauritius 1987–1992, and four of six in Mauritius 1987–1998. In contrast, an increase in waist circumference between baseline and follow-up was only predicted by insulin sensitivity (HOMA-S) at baseline, and only in one of the three cohorts. These results suggest that central obesity plays a central role in the development of the MetS and appears to precede the appearance of the other MetS components.

Cardiorespiratory fitness, but not central obesity or C-reactive protein, is related to liver function in obese children

Nonalcoholic fatty liver disease (NAFLD) is one of the most frequent complications associated with excess adiposity. Its pathogenesis is complex and there are multiple factors that may contribute to it. AIM: To analyze whether cardiorespiratory ftness (CRF), waist circumference (WC), and C-reactive protein (CRP) are associated with alanine aminotransferase (ALT) in children with obesity. METHODS: 79 overweight/obese children of both genders, 11-13 year-olds, with abnormal serum ALT from Porto public schools comprised the sample. Measurements included CRF (20-m Shuttle Run Test), WC (NHANES protocol), CRP and ALT (Cholestech LDX analyzer). Logistic regression adjusted for gender, maturation, and weight with ALT levels as dependent variable (risk vs. non risk), and WC (risk vs. non risk), CRP (risk vs. non risk), and CRF (fit vs. unfit) as independent variables. Level of significance was set at 95%. RESULTS: Logistic regression showed that obese fit children were less likely to have abnormal ALT values (OR=.031) CONCLUSION: In obese children, higher cardiovascular fitness appears to reduce the chance of decreased liver function. © 2013 Human Kinetics, Inc.

Dietary patterns are associated with general and central obesity in elderly living in a Brazilian city

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anthropometric measures of obesity-their association with type 2 diabetes and hypertension across ethnic groups

Clinical trials have shown that weight reduction with lifestyles can delay or prevent diabetes and reduce blood pressure. An appropriate definition of obesity using anthropometric measures is useful in predicting diabetes and hypertension at the population level. However, there is debate on which of the measures of obesity is best or most strongly associated with diabetes and hypertension and on what are the optimal cut-off values for body mass index (BMI) and waist circumference (WC) in this regard. The aims of the study were 1) to compare the strength of the association for undiagnosed or newly diagnosed diabetes (or hypertension) with anthropometric measures of obesity in people of Asian origin, 2) to detect ethnic differences in the association of undiagnosed diabetes with obesity, 3) to identify ethnic- and sex-specific change point values of BMI and WC for changes in the prevalence of diabetes and 4) to evaluate the ethnic-specific WC cutoff values proposed by the International Diabetes Federation (IDF) in 2005 for central obesity. The study population comprised 28 435 men and 35 198 women, ≥ 25 years of age, from 39 cohorts participating in the DECODA and DECODE studies, including 5 Asian Indian (n = 13 537), 3 Mauritian Indian (n = 4505) and Mauritian Creole (n = 1075), 8 Chinese (n =10 801), 1 Filipino (n = 3841), 7 Japanese (n = 7934), 1 Mongolian (n = 1991), and 14 European (n = 20 979) studies. The prevalence of diabetes, hypertension and central obesity was estimated, using descriptive statistics, and the differences were determined with the χ2 test. The odds ratios (ORs) or  coefficients (from the logistic model) and hazard ratios (HRs, from the Cox model to interval censored data) for BMI, WC, waist-to-hip ratio (WHR), and waist-to-stature ratio (WSR) were estimated for diabetes and hypertension. The differences between BMI and WC, WHR or WSR were compared, applying paired homogeneity tests (Wald statistics with 1 df). Hierarchical three-level Bayesian change point analysis, adjusting for age, was applied to identify the most likely cut-off/change point values for BMI and WC in association with previously undiagnosed diabetes. The ORs for diabetes in men (women) with BMI, WC, WHR and WSR were 1.52 (1.59), 1.54 (1.70), 1.53 (1.50) and 1.62 (1.70), respectively and the corresponding ORs for hypertension were 1.68 (1.55), 1.66 (1.51), 1.45 (1.28) and 1.63 (1.50). For diabetes the OR for BMI did not differ from that for WC or WHR, but was lower than that for WSR (p = 0.001) in men while in women the ORs were higher for WC and WSR than for BMI (both p < 0.05). Hypertension was more strongly associated with BMI than with WHR in men (p < 0.001) and most strongly with BMI than with WHR (p < 0.001), WSR (p < 0.01) and WC (p < 0.05) in women. The HRs for incidence of diabetes and hypertension did not differ between BMI and the other three central obesity measures in Mauritian Indians and Mauritian Creoles during follow-ups of 5, 6 and 11 years. The prevalence of diabetes was highest in Asian Indians, lowest in Europeans and intermediate in others, given the same BMI or WC category. The  coefficients for diabetes in BMI (kg/m2) were (men/women): 0.34/0.28, 0.41/0.43, 0.42/0.61, 0.36/0.59 and 0.33/0.49 for Asian Indian, Chinese, Japanese, Mauritian Indian and European (overall homogeneity test: p > 0.05 in men and p < 0.001 in women). Similar results were obtained in WC (cm). Asian Indian women had lower  coefficients than women of other ethnicities. The change points for BMI were 29.5, 25.6, 24.0, 24.0 and 21.5 in men and 29.4, 25.2, 24.9, 25.3 and 22.5 (kg/m2) in women of European, Chinese, Mauritian Indian, Japanese, and Asian Indian descent. The change points for WC were 100, 85, 79 and 82 cm in men and 91, 82, 82 and 76 cm in women of European, Chinese, Mauritian Indian, and Asian Indian. The prevalence of central obesity using the 2005 IDF definition was higher in Japanese men but lower in Japanese women than in their Asian counterparts. The prevalence of central obesity was 52 times higher in Japanese men but 0.8 times lower in Japanese women compared to the National Cholesterol Education Programme definition. The findings suggest that both BMI and WC predicted diabetes and hypertension equally well in all ethnic groups. At the same BMI or WC level, the prevalence of diabetes was highest in Asian Indians, lowest in Europeans and intermediate in others. Ethnic- and sex-specific change points of BMI and WC should be considered in setting diagnostic criteria for obesity to detect undiagnosed or newly diagnosed diabetes.

Overweight, obesity and metabolic syndrome in rural south-eastern Australia

Aims & rationale/Objectives : To measure the prevalence of overweight, obesity and the metabolic syndrome in rural Australia.</p>

Methods :Two cross-sectional population surveys of chronic disease risk factors were carried out in rural Victoria (Corangamite Shire) and South Australia (Limestone Coast) in 2004-05. For both surveys, a stratified random sample of the population aged 25 to 74 years was drawn from the electoral roll. The surveys comprised a self-administered questionnaire, physical measurements and laboratory tests.</p>

Principal findings : A total of 841 individuals had complete questionnaire, health check and measured MetS data. The prevalence of overweight and obesity was 75% in males and 64.7% in females defined by BMI. Using waist circumference, the prevalence of overweight and obesity was higher in females (72.9%) than in males (63.2%). The overall prevalence of obesity of was 30.1% when defined by BMI, but 44.8% when defined by waist circumference. The prevalence of metabolic syndrome according to NCEP ATP III 2005 criteria was 29.0% in males and 28.5% in females. According to IDF criteria, the prevalence for males and females were 30.5% and 36.3%, respectively. The prevalence of metabolic syndrome and central (abdominal) obesity, hyperglycaemia, hypertension, and hypertriglyceridaemia increased with age.

Discussion : The prevalence of overweight and obesity, in particular central obesity, in rural Australia is very high as is the prevalence of metabolic syndrome.

Implications : Urgent population wide action is required to turn this trend around and regular monitoring of the trends in response to such action is essential.

The influence of hip circumference on the relationship between abdominal obesity and mortality

Background Higher waist circumference and lower hip circumference are both associated with increased cardiovascular disease (CVD) risk, despite being directly correlated. The real effects of visceral obesity may therefore be underestimated when hip circumference is not fully taken into account. We hypothesized that adding waist and hip circumference to traditional risk factors would significantly improve CVD risk prediction.

Methods In a population-based survey among South Asian and African Mauritians (n = 7978), 1241 deaths occurred during 15 years of follow-up. In a model that included variables used in previous CVD risk calculations (a Framingham-type model), the association between waist circumference and mortality was examined before and after adjustment for hip circumference. The percentage with an increase in estimated 10-year cumulative mortality of >25% and a decrease of >20% after waist and hip circumference were added to the model was calculated.

Results Waist circumference was strongly related to mortality only after adjustment for hip circumference and vice versa. Adding waist and hip circumference to a Framingham-type model increased estimated 10-year cumulative CVD mortality by >25% for 23.7% of those who died and 15.7% of those censored. Cumulative mortality decreased by >20% for 4.5% of those who died and 14.8% of those censored.

Conclusions The effect of central obesity on mortality risk is seriously underestimated without adjustment for hip circumference. Adding waist and hip circumference to a Framingham-type model for CVD mortality substantially increased predictive power. Both may be important inclusions in CVD risk prediction models.

The effect of obesity on polycystic ovary syndrome : a systematic review and meta-analysis

While many women with polycystic ovary syndrome (PCOS) are overweight, obese or centrally obese, the effect of excess weight on the outcomes of PCOS is inconsistent. The review aimed to assess the effects of overweight, obesity and central obesity on the reproductive, metabolic and psychological features of PCOS. MEDLINE, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL) and PSYCINFO were searched for studies reporting outcomes according to body mass index categories or body fat distribution. Data were presented as mean difference or risk ratio (95% confidence interval). This review included 30 eligible studies. Overweight or obese women with PCOS had decreased sex hormone-binding globulin (SHBG), increased total testosterone, free androgen index, hirsutism, fasting glucose, fasting insulin, homeostatic model assessment-insulin resistance index and worsened lipid profile. Obesity significantly worsened all metabolic and reproductive outcomes measured except for hirsutism when compared to normal weight women with PCOS. Overweight women had no differences in total testosterone, hirsutism, total-cholesterol and low-density lipoprotein-cholesterol compared to normal weight women and no differences in SHBG and total testosterone compared to obese women. Central obesity was associated with higher fasting insulin levels. These results suggest that prevention and treatment of obesity is important for the management of PCOS.

The effect of physical activity on psychological distress, cortisol and obesity: results of the farming fit intervention program

Background:
Rural and regional Australians have a higher likelihood of mental illness throughout their lifetime than people living in major cities, although the underlying reasons are not yet well defined. Additionally, rural populations experience more lifestyle associated co-morbidities including obesity, diabetes and cardiovascular disease. Research conducted by the National Centre for Farmer Health between 2004 and 2009 revealed a positive correlation between obesity and psychological distress among the farming community. Chronic stress is known to overstimulate the regulation of the hypothalamic-pituitary-adrenal (HPA) axis and cortisol secretion which are associated with abdominal adiposity. Increasing physical activity may normalise cortisol secretion and thereby positively impact both physical and mental health. This paper assesses the effects of increasing physical activity on obesity, health behaviors and mental health in Victorian farming men and women.

Methods:
Farming Fit was a six month quasi-experimental (convenience sample) longitudinal design control-intervention study. Overweight or obese (BMI ?25?kg/m2) farm men (n?=?43) and women (n?=?29) were recruited with demographic, health behaviors, anthropometric, blood pressure and biochemistry data collected at baseline and at a six months. Salivary cortisol and depression anxiety stress scale results were collected at baseline, three and six months. The intervention group (n?=?37) received a personalized exercise program and regular phone coaching to promote physical activity.

Results:
The intervention group showed significant reductions in body weight and waist circumference. Results indicated that following the six month exercise program, the intervention group were 2.64???0.65?kg lighter (p?<?0.001), had reduced waist circumference by 2.01???0.86?cm (p?=?0.02) and BMI by 0.97???0.22?kg/m2 (p?<?0.001) relative to the control group.

Conclusion:
Increasing physical activity altered measures of obesity in farm men and women but did not affect mental health measures or cortisol secretion levels.

The impact of interventions to prevent obesity or improve obesity related behaviours in children (0-5 years) from socioeconomically disadvantaged and/or indigenous families: a systematic review

Background
Children from disadvantaged families including those from low socioeconomic backgrounds and Indigenous families have higher rates of obesity, making early intervention a priority. The aim of this study was to systematically review the literature to examine the effectiveness of interventions to prevent obesity or improve obesity related behaviours in children 0-5 years from socioeconomically disadvantaged or Indigenous families.

Methods
Searches of major electronic databases identified articles published from 1993–2013 targeting feeding practices, anthropometric, diet, activity or sedentary behaviour outcomes. This was supplemented with snowballing from existing reviews and primary studies. Data extraction was undertaken by one author and cross checked by another. Quality assessments included both internal and external validity.

Results
Thirty-two studies were identified, with only two (both low quality) in Indigenous groups. Fourteen studies had a primary aim to prevent obesity. Mean differences between intervention and control groups ranged from -0.29 kg/m2 to -0.54 kg/m2 for body mass index (BMI) and -2.9 to -25.6% for the prevalence of overweight/obesity. Interventions initiated in infancy (under two years) had a positive impact on obesity related behaviours (e.g. diet quality) but few measured the longer-term impact on healthy weight gain. Findings amongst pre-schoolers (3–5 years) were mixed, with the more successful interventions requiring high levels of parental engagement, use of behaviour change techniques, a focus on skill building and links to community resources. Less than 10% of studies were high quality. Future studies should focus on improving study quality, including follow-up of longer-term anthropometric outcomes, assessments of cost effectiveness, acceptability in target populations and potential for implementation in routine service delivery.

Conclusion
There is an urgent need for further research on effective obesity prevention interventions for Indigenous children. The findings from the growing body of intervention research focusing on obesity prevention amongst young children from socioeconomically disadvantaged families suggest intervention effects are modest but promising. Further high quality studies with longer term follow up are required.

Índices de obesidade central e fatores de risco cardiovascular na síndrome dos ovários policísticos

Fundamento: A obesidade abdominal apresenta elevada prevalência em mulheres com síndrome dos ovários policísticos (SOP) e está associada a um aumento do risco cardiovascular. Objetivo: Verificar a acurácia da circunferência da cintura (CC), da relação cintura-quadril (RCQ), da relação cinturaestatura (RCEST) e do índice de conicidade (índice C), no que se refere à detecção de fatores de risco cardiovascular (FRCV) em mulheres com SOP. Métodos: Por meio de estudo transversal, foram alocadas 102 mulheres (26,5 ± 5 anos) com diagnóstico de SOP, de acordo com o consenso de Rotterdam. O colesterol total (CT), os triglicerídeos (TG), o LDL-colesterol (LDL-C), o HDLcolesterol (HDL-C), a glicemia de jejum, a glicemia após teste oral de tolerância à glicose (TOTG) e a pressão arterial (PA) foram avaliados em todas as pacientes, além das variáveis antropométricas. Resultados: A relação cintura-estatura foi o marcador que apresentou correlações positivas significativas com o maior número de FRCV (PA, TG e glicemia após TOTG), destacando-se ainda a correlação negativa com HDL-C. Todos os marcadores antropométricos avaliados se correlacionaram positivamente com PA, enquanto CC e RCQ apresentaram correlação positiva também com TG. No tocante à acurácia para detecção de FRCV, os indicadores antropométricos considerados apresentaram taxas de sensibilidade superiores a 60%, com destaque para a RCEST, que apresentou sensibilidade superior a 70%. Conclusão: A RCEST demonstrou ser o indicador antropométrico com a melhor acurácia para a predição de FRCV. Nesse sentido, propõe-se a inclusão desse parâmetro de fácil mensuração na avaliação clínica para o rastreamento de mulheres com SOP e FRCV----------------------ABSTRACT Background: Women with polycystic ovary syndrome (PCOS) present a high prevalence of abdominal obesity, which is associated with an increased cardiovascular risk. Objective: To verify the accuracy of the waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and the conicity index (CI) in the detection of cardiovascular risk factors (CVRF) in women with PCOS. Methods: The present transversal study allocated 102 women (26.5 ± 5 years) with a diagnosis of PCOS, according to the Rotterdam criteria. Total cholesterol (TC), triglycerides (TG), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), fasting glucose, glucose after the oral glucose tolerance test (OGTT) and blood pressure (BP) were evaluated in all patients, in addition to the anthropometric variables. Results: The WHtR was the marker that presented significant positive correlations with the highest number of CVRF (BP, TG and post-OGTT glucose), whereas there was a negative correlation with HDL-C. All the evaluated anthropometric markers were positively correlated with BP, whereas WC and WHR also presented a positive correlation with TG. Regarding the accuracy for the detection of CVRF, the anthropometric markers presented a sensibility > 60%, especially the WHtR, which had a sensibility > 70%. Conclusion: The WHtR showed to be the most accurate anthropometric indicator for the prediction of CVRF. In this sense, we propose the inclusion of this easily-measured parameter in the clinical assessment for the screening of women with PCOS and CVRF

Influência da atividade e inatividade física na composição corporal e adiposidade central

To analyze influences of the physical activity and sedentary behaviors on indicators of both central and total body fat in male adolescents. Cross-sectional study with 60 male students of age range from 11 to 14 years old. It were evaluated the body mass, height, triceps skinfold, waist circumference, body fat percentage (bioelectrical impedance) and the physical activity level through questionnaire. The physical inactivity prevalence was of 35%, and the excessive total and central body fat were observed in 38.3% and 48.3% of the sample, respectively. There was association of the sedentary behaviors with the excessive total and central body fat (OR = 5.2 e OR = 6.4, respectively), however there was not for physical activity. The adoption of sedentary behaviors is associated at the development of the total and central obesity among male adolescents.