Ethnic disparities in prevalence and clustering of cardiovascular disease risk factors in rural Southwest China.

BACKGROUND: This study examines how prevalence and clustering of cardiovascular disease (CVD) risk factors differ by ethnicity and socioeconomic status (SES) among rural southwest Chinese adults. METHODS: A cross-sectional survey of 7027 adults aged ≥35 years of Han and four ethnic minority group descent (Na Xi, Li Shu, Dai, and Jing Po) was used to derive prevalence of tobacco smoking and exposure to secondhand smoke (SHS) as well as alcohol consumption and physical activity data. Anthropometric measurements were also taken, including height, weight, and waist and hip circumference, as well as blood pressure (BP) and fasting blood glucose (FBG) measurements. RESULTS: Current smoking and drinking status were the top two CVD risk factors in the study population. Dai ethnic minority participants had the highest prevalence of hypertension, obesity, and central obesity, whereas Jing Po ethnic minority participants had the highest prevalence of current smoking status, SHS exposure, and current drinking status (P < 0.01). Han participants had the highest prevalence of diabetes and physical inactivity (P < 0.01). 11.1% of all participants did not have any of the studied CVD risk factors, while 68.6% of Han, 60.2% of Na Xi, 50.7% of Li Shu, 82.2% of Dai, and 73.0% of Jing Po participants had clustering of two or more CVD risk factors. Prevalence of CVD risk factor clusters increased with age (P < 0.01). Males and individuals with lower education levels and lower annual household income were more likely to have CVD risk factors than their counterparts (P < 0.01). CONCLUSION: Clustering of CVD risk factors is common in rural southwest China. Ethnicity and individual SES significantly impact prevalence of CVD risk factors and their clustering.

Prevalence of and Factors Associated with Metabolic Syndrome in Afro-Descendant Communities in a Situation of Vulnerability in Northern Brazil: A Cross-Sectional Study.

Background: Quilombos are Brazilian communities developed by survivor groups following fight against slavery. They are found in the whole of the Brazilian territory, far from urban centers, living in vulnerable and poor socioeconomic situations and continuously suffering from influence of occidentalization. Based on the hypothesis that the way Quilombolas live may be associated with metabolic syndrome (MS), the objective of this study was to estimate the prevalence of MS and to analyze the associated factors in adult residents of Quilombola communities in the northern region of Brazil. Methods: A cross-sectional study was conducted according to the guidelines of the STROBE Statement in five communities of Tocantins. Results: The study investigated 193 individuals who lived for at least 1 year in the communities. The prevalence of MS in this population was 32.12%. There was a higher prevalence of MS or metabolic disorders in women, as well as metabolic profiles related to low high-density lipoprotein and obesity among participants with MS. Conclusion: The prevalence of MS is higher compared with other Quilombola and African communities, indicating an opportunity to improve or develop new programs to reduce MS and metabolic disorders, by making changes in some habits, such as physical activities, because there were differences in metabolic disorders related to the presence of MS.

The Role of Energy Intake on Fitness-Adjusted Racial/Ethnic Differences in Central Adiposity Using Quantile Regression.

BACKGROUND: Energy intake (EI) is suggested to be associated with adiposity and may explain previously observed fitness-adjusted racial disparities in waist circumference (WC). OBJECTIVE: The purpose of this study was to comprehensively evaluate the role of EI on the fitness-adjusted racial/ethnic disparities in WC in a nationally representative sample of females using quantile regression. METHODS: Our sample consisted of 3874 female participants (aged 12 to 49 years) from the 1999-2004 National Health and Nutrition Examination Survey. The role of EI was assessed in separate analyses via estimation using a 24-hour dietary recall (DR) and the Institute of Medicine total daily energy expenditure equations. Age-stratified quantile regression models were used to estimate the differences in WC between minority groups and non-Hispanic (NH) white, adjusting for EI, CRF, age, and height. RESULTS: Results from the quantile regression analyses adjusting for EI via DR showed significant differences in WC between NH black and NH white at the 25th-90th WC percentiles (5.9-11.1 cm) for females 20-49 and at the 90th WC percentile (10.1 cm) for females 16-19. For females 12-15, no significant differences were observed between NH black and NH white. Analyses adjusting for EI via IOM showed significant differences in WC between NH black and NH white only for females aged 20-49 years, at the 50th and 75th percentile (1.7-3.6 cm). Compared to NH White, Mexican American females, in all age groups, tended to have significantly greater WC. CONCLUSIONS: These results highlight the importance of rigor in energy intake assessments, suggesting that EI, if adequately assessed, may explain a substantial part of the racial/ethnic differences in WC between NH black and NH white females. Additionally, the observed persistence of estimated differences in WC with advancing age suggests other factors (e.g., hormones) may play a role.

Visceral fat is associated with the racial differences in liver fat between black and white adolescent boys with obesity.

OBJECTIVE: We examined whether racial differences in liver fat are associated with the differences in abdominal fat distribution or cardiorespiratory fitness (CRF). METHODS: Participants included 57 black and white obese boys (12-18 years). Total and abdominal fat was measured by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging, respectively. CRF was measured using a maximal graded treadmill test with the use of standard open-circuit spirometry techniques until volitional fatigue. Liver fat was measured using a 3T proton magnetic resonance spectroscopy. Fatty liver was defined as having liver fat ≥5%. RESULTS: In the sample, 16.1% of black boys and 30.8% of white boys had fatty liver. Liver fat was associated (P ≤ .05) with body mass index (BMI) percentile (r = 0.28), total fat (r = 0.31), waist circumference (r = 0.38), visceral fat (r = 0.62), abdominal subcutaneous adipose tissue (r = 0.30), and CRF (r = -0.27) adjusting for age and race. White boys had greater liver fat than black boys with adjustment for age and differences in BMI percentile or CRF, but not with waist circumference or visceral fat (P > .05). In a model with age, ethnicity, total body fat, fat-free mass, visceral fat, abdominal subcutaneous fat, and CRF, visceral fat was the only factor to be independently associated with increased odds of having fatty liver (OR = 1.12; 95% CI: 1.04-1.21; P = .003). CONCLUSION: The racial disparities in liver fat between obese black vs white adolescents are explained, in part, by differences in visceral fat.

[Educational inequality in the occurrence of abdominal obesity according to gender and color/race: the Pro-Health Study, 1999-2001 and 2011-2012]. / Desigualdade educacional na ocorrência de obesidade abdominal por gênero e cor/raça: Estudo Pró-Saúde, 1999-2001 e 2011-2012.

Cross-sectional data from the Pro-Health Study in 1999-2001 and 2011-2012 revealed important gender and color/race differences in the size and variation across time in educational inequalities related to abdominal obesity. Probability of obesity increased steadily in women (independently of color/race) and men (brown/black) with less schooling. These gradients were quantified according to the relative index of inequality (RII). Over the course of the decade, there was a reduction in inequality in brown/black women (ΔRII: 0.5; 95%CI: 0.2-1.1), underlying a relatively higher increase in the prevalence of abdominal obesity in women with more schooling. RII was stable in white women and brown/black men, indicating a similar increase in the prevalence of abdominal obesity in educational subgroups. The association between schooling and abdominal obesity was affected by the multiple interaction of socio-demographic factors. Our results recommend joint stratification by gender and color/race in the study of socioeconomic inequalities related to abdominal obesity.

Desigualdade educacional na ocorrência de obesidade abdominal por gênero e cor/raça: Estudo Pró-Saúde, 1999-2001 e 2011-2012 / Educational inequality in the occurrence of abdominal obesity according to gender and color/race: the Pro-Health Study, 1999-2001 and 2011-2012 / Desigualdad educacional en la ocurrencia de la obesidad abdominal por género y color/raza: Estudio Pro-Salud, 1999-2001 e 2011-2012

Resumo Análise de dados seccionais do Estudo Pró-Saúde (1999-2001 e 2011-2012) revelou importante diferença de gênero e cor/raça na magnitude e variação temporal da desigualdade educacional na obesidade abdominal. Probabilidade de estar obeso foi gradativamente maior em mulheres (independentemente de cor/raça) e homens (pardos/pretos) menos escolarizados. Tais gradientes foram quantificados pelo índice relativo de desigualdade (IRD). Ao longo da década, observou-se redução da desigualdade em mulheres pardas/pretas (ΔIRD: 0,5; IC95%: 0,2-1,1), subjacente ao relativo aumento da prevalência de obesidade abdominal entre as mais escolarizadas. Houve estabilidade do IRD em mulheres brancas e homens pardos/pretos, indicando crescimento similar da prevalência de obesidade abdominal nos subgrupos educacionais. Associação da escolaridade com a ocorrência de obesidade abdominal sofreu interação múltipla de fatores sociodemográficos. Nossos resultados encorajam a estratificação conjunta por gênero e cor/raça no estudo das desigualdades socioeconômicas na ocorrência da obesidade abdominal.

Abstract Cross-sectional data from the Pro-Health Study in 1999-2001 and 2011-2012 revealed important gender and color/race differences in the size and variation across time in educational inequalities related to abdominal obesity. Probability of obesity increased steadily in women (independently of color/race) and men (brown/black) with less schooling. These gradients were quantified according to the relative index of inequality (RII). Over the course of the decade, there was a reduction in inequality in brown/black women (ΔRII: 0.5; 95%CI: 0.2-1.1), underlying a relatively higher increase in the prevalence of abdominal obesity in women with more schooling. RII was stable in white women and brown/black men, indicating a similar increase in the prevalence of abdominal obesity in educational subgroups. The association between schooling and abdominal obesity was affected by the multiple interaction of socio-demographic factors. Our results recommend joint stratification by gender and color/race in the study of socioeconomic inequalities related to abdominal obesity.

Resumen Los análisis de datos seccionales del Estudio Pro-Salud durante los períodos 1999-2001 y 2011-2012 reveló una importante diferencia de género y color/raza en la magnitud y variación temporal de la desigualdad educacional en la obesidad abdominal. La probabilidad de estar obeso fue gradualmente mayor en mujeres (independiente de color/raza) y hombres (mulatos/negros) menos escolarizados. Tales gradientes fueron cuantificados por el índice relativo de desigualdad (IRD). A lo largo de la década, se observó una reducción de la desigualdad en mujeres mulatas/negras (ΔIRD: 0,5; IC95%: 0,2-1,1), subyacente al aumento relativamente mayor de la prevalencia de obesidad abdominal entre las más escolarizadas. Hubo estabilidad del IRD en mujeres blancas y hombres mulatos/negros, indicando crecimiento similar de la prevalencia de obesidad abdominal en los subgrupos educacionales. Asociación de la escolaridad con la ocurrencia de obesidad abdominal sufrió una interacción múltiple de factores sociodemográficos. Nuestros resultados muestran la estratificación conjunta por género y color/raza en el estudio de las desigualdades socioeconómicas en el ámbito de la obesidad abdominal.

Ethnic disparities in general and abdominal adiposity at school age: a multiethnic population-based cohort study in the Netherlands.

BACKGROUND/AIMS: Ethnic differences in obesity prevalence have been reported. We examined ethnic differences in general and abdominal fat distribution in school-age children and the influence of parental prepregnancy, pregnancy, and childhood factors on these differences. METHODS: We performed a multiethnic population-based prospective cohort study among 5,244 children with information about prepregnancy factors, pregnancy, and childhood factors. At the age of 6 years, the BMI, total fat mass, android/gynoid fat mass ratio, and preperitoneal fat mass were assessed via dual-energy X-ray absorptiometry and abdominal ultrasound. RESULTS: The overweight and obesity prevalences among Dutch children were 10.0 and 2.1%, respectively. Higher prevalences were observed among Cape Verdean (21.0 and 10.3%), Dutch Antillean (18.4 and 13.8%), Moroccan (20.6 and 7.7%), Surinamese-Creole (13.4 and 7.7%), Surinamese-Hindustani (12.3 and 6.2%), and Turkish (23.8 and 12.0%) children. In the models adjusted for age and sex only, Moroccan, Surinamese-Hindustani, and Turkish children had a higher total fat mass than Dutch children, whereas Surinamese-Creole children had a lower total fat mass. Compared to Dutch children, the android/gynoid fat mass ratio was higher in Moroccan, Surinamese-Hindustani, and Turkish children, whereas the preperitoneal fat mass was higher among Dutch Antillean, Moroccan, Surinamese-Hindustani, and Turkish children (all p < 0.05). Prepregnancy factors explained up to 73% of these differences. In addition to prepregnancy factors, pregnancy factors explained up to 34% of the differences. Childhood factors did not significantly explain these associations. CONCLUSIONS: All ethnic minority groups had higher risks of overweight and obesity than Dutch children. Moroccan, Surinamese-Hindustani, and Turkish children also had an adverse body fat profile. Prepregnancy and pregnancy might be critical periods for preventive strategies focused on the reduction of ethnic disparities in childhood adiposity.

Ethnic differences in prevalence of general obesity and abdominal obesity among low-income rural Kazakh and Uyghur adults in far western China and implications in preventive public health.

BACKGROUND: The global pandemic of obesity has become a disastrous public health issue that needs urgent attention. Previous studies have concentrated in high-income urban settings and few cover low-income rural settings especially nomadic residents in mountain areas. This study focused on low-income rural and nomadic minority people residing in China's far west and investigated their prevalence and ethnic differences of obesity. METHODS: A questionnaire-based survey and physical examination of 8,036 individuals were conducted during 2009-2010, using stratified cluster random sampling method in nomadic Kazakhs and rural Uyghur residents (≥ 18 years old) in 18 villages, Xinjiang, China, about 4,407 km away from capital Beijing. Obesity was defined by BMI and WC. RESULTS: The overall prevalence of general and abdominal obesity in Kazakh adults were 18.3% and 60.0%, respectively and in Uyghur, 7.6% and 54.5%, respectively. Female's prevalence of obesity was higher than male's for general obesity (45-54 age group in Uyghur, P = 0.041) and abdominal obesity (≥ 55 years in Kazakhs, P(55 ∼) = 0.010, P(65 ∼) = 0.001; and ≥ 18 years in Uyghurs, P<0.001). Kazakh's prevalence of obesity was higher than Uyghur's (general obesity: ≥ 35 years, P<0.001; abdominal obesity: ≥ 25 years in males and ≥ 65 years in females, P<0.01). The prevalence of obesity increased after 18 years old and subsequently decreased after 55 years old. Meat consumption, older age, and female gender had a higher risk of obesity in these two minorities. CONCLUSIONS: Both general and abdominal obesity were common in rural ethnic Kazakhs and Uyghurs. The prevalence rates were different in these two minorities depending on ethnicity, gender, and age. Kazakhs, females and elderly people may be prioritized in prevention of obesity in western China. Because of cost-effectiveness in measuring BMI and WC, we recommend that BMI and WC be integrated into local preventive policies in public health toward screening obesity and related diseases in low-income rural minorities.

Abdominal adiposity and family income-to-poverty ratio in American women.

OBJECTIVE: We examined (a) secular changes in abdominal fat accumulation (AFA) and family income-to-poverty ratio (PIR) across race/ethnicity, education and age in Mexican (MA), non-Hispanic Whites (NHW), non-Hispanic Black (NHB), and (b) association between PIR and AFA among American women. METHODS: Data (n = 9787) from 2001-2002 to 2009-2010 NHANES were used. Rates of AFA and poverty by race/ethnic, age and education categories were determined across study time points. Subjects with low and medium PIR values were classified as poor. Linear trends in AFA and PIR were evaluated. Study time-specific odds ratios (OR) from logistic regression models were used to estimate risk of AFA due to low to medium PIR. Statistical adjustments were made for race/ethnicity, education, age, and marital status. RESULTS: Increased trends in low to medium PIR and AFA in MA, NHW, and NHB American women were observed between 2001 and 2010. Poor women had much higher prevalence of AFA compared to richer women. For each of the studied periods, medium and low PIR were each associated with increased odds of AFA. The association between poverty and AFA was weakest in 2001-2002 (OR = 1.49, 95% CI: 1.05-2.11) compared to 2009-2010 (OR = 1.64, 95% CI: 1.21-2.22). Compared to NHW, being of MA and NHB race/ethnicity was also each associated with increased odds of AFA, controlling for other independent variables. CONCLUSIONS: Increase in poverty and AFA, and positive association between decreased PIR and increased odds of AFA were observed in the period between 2001 and 2010 in MA, NHW, and NHB American women. A robust economic policy designed to alleviate poverty may be an important means of reducing the trajectory of AFA in American women.

Ethnic-immigrant disparities in total and abdominal obesity in the US.

OBJECTIVES: To examine sex-specific disparities in total and abdominal obesity prevalence across 6 ethnic-immigrant groups and explore whether the observed differences were attributable to diet and physical activity (PA). METHODS: Data were from 4331 respondents age 18-64 from the 2003-2006 National Health and Nutrition Examination Survey. Sex-specific multiple logistic regression analyses were performed. RESULTS: Regardless of race-ethnicity, immigrants exhibited lower prevalence of total and abdominal obesity than natives. Among the US-born, Whites had the lowest total obesity prevalence followed by Hispanics and then Blacks; but racial-ethnic disparities for immigrants were different. In abdominal obesity, US-born white men had the highest prevalence. PA helped explain some ethnic-immigrant disparities. CONCLUSIONS: Complex interactions of sex by race-ethnicity and nativity exist for obesity prevalence.

Clinical importance of assessment of type 2 diabetes mellitus with visceral obesity. A Japanese perspective.

Type 2 diabetes mellitus (T2DM) is a complex heterogeneous group of metabolic disorders including hyperglycemia and impaired insulin action and/or insulin secretion. Obesity T2DM has become a serious problem in Japan as in Western countries, with over-eating and physical inactivity. Obese Asians have mild degree of adiposity, compared with Western subjects. Unlike total body fat, body fat distribution, especially excess accumulation of visceral fat, correlates with various diabetogenic, atherogenic, prothrombotic and proinflammatory metabolic abnormalities, which increase the risk of atherosclerotic cardiovascular disease (ACVD). Obese patients with T2DM have poor glycemic control with disordered eating behaviors, and complications of hypertension and dyslipidemia, leading to ACVD. The major therapies in obese T2DM, hyperinsulinemia and low insulin sensitivity, available for weight loss, especially visceral fat reduction, include caloric restriction, physical activity and behavior modification. On the other hand, the major therapies in non-obese T2DM with insufficient insulin secretion, are insulin-secretory agents and injectable insulin. For clinically meaningful prevention/reduction in the rate of future ACVD in T2DM, it may be important to stratify T2DM subjects into those with and without visceral obesity and design specific management protocols for each group.

Ethnic and gender disparities in adolescent obesity and elevated systolic blood pressure in a rural US population.

A cross-sectional study was conducted to assess the prevalence of overweight, obesity, and elevated systolic blood pressure (SBP) in ethnically diverse adolescents (1064 males; 974 females; 13-17 years) in a rural community. Prevalence of overweight was 20.4% in females and 17.5% in males. In contrast, the prevalence of obesity was 29.4% in males and 14.5% in females. African American males had the highest prevalence of obesity (33.3%) compared with non-Hispanic whites (26.3%). Prevalence of elevated SBP was higher than pre-elevated SBP in males regardless of race/ethnicity, but not in females. Obese females had 4-fold and 9-fold greater odds of developing pre-elevated SBP and elevated SBP, respectively, than their normal weight cohorts. Prevalence of obesity is almost twice that of overweight in males in our rural population suggesting that adolescent males from disadvantaged, rural populations are potentially at a greater risk for metabolic disorders than those in major metropolitan areas.

Allostatic load is associated with chronic conditions in the Boston Puerto Rican Health Study.

Puerto Ricans living in the United States mainland present multiple disparities in prevalence of chronic diseases, relative to other racial and ethnic groups. Allostatic load (AL), or the cumulative wear and tear of physiological responses to stressors such as major life events, social and environmental burden, has been proposed as a possible mechanism for the inequalities observed in minority groups, but has not been studied in Puerto Ricans. The aim of this study was to determine the association of AL to six chronic diseases (abdominal obesity, hypertension, diabetes, and self-reported cardiovascular disease (CVD), arthritis and cancer) in Puerto Ricans, and to contrast AL to metabolic syndrome (MetS). Participants of the Boston Puerto Rican Health Study (n=1116, ages 45-75 years) underwent a home-based interview, where questionnaires were completed and biological samples collected. A summary definition of AL was constructed using clinically-defined cutoffs and medication use for 10 physiological parameters in different body systems. Logistic regression models were run to determine associations between AL score and disease status, controlling for age, sex, smoking, alcohol use, physical activity, total fat intake and energy intake. Parallel models were also run with MetS score replacing AL. We found that increasing categories of AL score were significantly associated with abdominal obesity, hypertension, diabetes and self-reported cardiovascular disease (CVD) and arthritis, but not with self-reported cancer. The strength of associations of AL with all conditions, except diabetes and cancer, was similar to or larger than those of MetS score. In conclusion, Puerto Rican older adults experienced physiological dysregulation that was associated with increased odds of chronic conditions. AL was more strongly associated with most conditions, compared to MetS, suggesting that this cumulative measure may be a better predictor of disease. These results have prospective research implications for Puerto Ricans and other ethnic groups.

Assessment of total and central adiposity in Canadian Aboriginal children and their Caucasian peers.

OBJECTIVE: Although Aboriginal children seem to be more susceptible to developing obesity and metabolic disorders than other ethnic groups in Canada, few studies have examined adiposity comprehensively in this population. The purpose of this study was to assess total and central adiposity in Canadian Aboriginal and Caucasian children matched by age, gender and maturity. METHODS: A total of 212 Aboriginal and 204 Caucasian children (8-17 years) were recruited. Heights, weights and waist circumferences were measured and classified using international standards. Dual energy x-ray absorptiometry (DXA) indicated relative total body and trunk fatness. Age of peak height velocity was predicted from somatic growth. Descriptives with independent t-tests and Chi-square analyses were run to detect ethnic differences. ANCOVA was used to assess differences in total body and trunk fatness (covariates height, chronological age and biological age) in girls and boys separately. RESULTS: Overweight/obesity and central adiposity were more prevalent in Aboriginal children compared with Caucasian children (p < 0.05). Ethnic differences in total body and trunk fatness were also significant, with Aboriginal girls and boys presenting, on average, 5.4% and 6.0% more total body fatness and 7.6% and 8.3% more trunk fatness, than Caucasian girls and boys, respectively (p < 0.01). CONCLUSION: Canadian Aboriginal children have greater prevalence of overweight/obesity and central adiposity, and higher relative total body fatness and trunk fatness than their Caucasian peers, which may predispose them to cardiovascular and metabolic disorders at a very young age. Longitudinal research is needed to confirm the associated health risks in this population.

Gender and ethnic differences in arterial compliance in patients with intermittent claudication.

OBJECTIVE: To assess the gender and ethnic differences in arterial compliance in patients with intermittent claudication. METHODS: A total of 114 patients participated, including 38 Caucasian men, 32 Caucasian women, 16 African American men, and 28 African American women. Patients were assessed on large artery elasticity index (LAEI), small artery elasticity index (SAEI), age, weight, body mass index, ankle-brachial index (ABI), smoking status, and metabolic syndrome components. RESULTS: Group differences were found for LAEI (P = .042), SAEI (P = .019), body mass index (P = .020), prevalence of elevated fasting glucose (P = .001), and prevalence of abdominal obesity (P = .025). Significant covariates for LAEI included age (P = .0002) and elevated triglycerides (P = .0719). LAEI (units = 10 mL x mm Hg) adjusted for age and triglycerides was 39% lower (P = .0005) in African Americans (11.4 +/- .90; mean +/- SE) than in Caucasians (15.8 +/- 0.72), whereas no significant difference (P = .7904) existed between men (13.8 +/- 0.81) and women (13.5 +/- 0.79). Significant covariates for SAEI included age (P = .0001), abdominal obesity (P = .0030), and elevated blood pressure (P = .0067). SAEI (units = 100 mL x mm Hg) adjusted for age, abdominal obesity, and elevated blood pressure was 32% lower (P = .0007) in African-Americans (2.8 +/- 0.3) than in Caucasians 4.1 +/- 0.2), and was 18% lower (P = .0442) in women (3.1 +/- 0.2) than in men (3.8 +/- 0.2). CONCLUSION: African American patients with intermittent claudication have more impaired macrovascular and microvascular function than Caucasian patients, and women have more impaired microvascular function than men. These ethnic and gender differences in arterial compliance are evident even though ABI was similar among groups, suggesting that arterial compliance provides unique information to quantify vascular impairment in patients with intermittent claudication.

Life-course socio-economic factors, skin colour and abdominal obesity in adulthood in a Brazilian birth cohort.

OBJECTIVE: Obesity is an increasingly prevalent nutritional disorder throughout the world. In particular, abdominal obesity is associated with cardiovascular and metabolic risk. The present study aimed to evaluate the effects of skin colour and life-course socio-economic indicators on waist circumference (WC), hip circumference (HC) and waist:hip ratio (WHR) in young adults. DESIGN: Population-based birth cohort study. Individuals born in 1982 in Pelotas (southern Brazil) were visited on a number of occasions from birth to age 23-24 years. A sample of the cohort was sought in 2006 and 972 individuals were located. The analysis was restricted to individuals with complete data available (442 males, 414 females). RESULTS: In men, family income at birth and in 2004-5 were positively associated with WC and HC, but not with WHR. Regardless of current income, men born to wealthier families had larger WC and HC as adults. Skin colour was not associated with any of the outcomes. In women, early poverty was associated with smaller HC, and current poverty with larger WC. Poverty at any age thus led to higher WHR. Black women had larger WC and HC than white women, but there were no differences in WHR. All the associations were partially mediated by education and behavioural variables. CONCLUSIONS: The effects of early socio-economic position on WC and HC persist even after adjustment for adult socio-economic position, highlighting the importance of interventions during the first years of life.

Association of serum leptin levels with homeostasis model assessment-estimated insulin resistance and metabolic syndrome: the key role of central obesity.

BACKGROUND: Leptin is correlated with several features of metabolic syndrome; however, possible confounders (eg, obesity) of this association are not known. This study evaluated the relationship between leptin, metabolic syndrome, and insulin resistance in an Iranian population and further investigated whether this relationship is confounded by obesity or central obesity. METHODS: A total of 387 participants (18-65 years old) who referred to a large university general hospital for routine health examinations were categorized into 2 groups with (n = 130) and without (n = 257) metabolic syndrome. Fasting plasma glucose, insulin, lipids, and leptin levels were measured and the homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. RESULTS: Age- and sex-adjusted leptin levels were significantly higher in patients with than those without metabolic syndrome (29.62 +/- 1.67 vs. 18.50 +/- 1.21 ng/mL, P < 0.001). After adjustment for age, sex, and body mass index (BMI), leptin values were significantly correlated with HOMA-IR (P < 0.001), metabolic syndrome, and its components (P < 0.05). After adjustment for waist circumference, however, these associations were no longer statistically significant. CONCLUSIONS: We demonstrated that high leptin levels are associated with insulin resistance and metabolic syndrome independent of BMI but these associations are significantly mediated through the effects of central obesity.