Comparison of diagnostic criteria of the metabolic syndrome in 3 ethnic groups of Canada

Ethnic differences in metabolic syndrome in high-income countries: A systematic review and meta-analysis

This review aimed to systematically quantify the differences in Metabolic Syndrome (MetS) prevalence across various ethnic groups in high-income countries by sex, and to evaluate the overall prevalence trends from 1996 to 2022. We conducted a systematic literature review using MEDLINE, Web of Science Core Collection, CINAHL, and the Cochrane Library, focusing on studies about MetS prevalence among ethnic groups in high-income countries. We pooled 23 studies that used NCEP-ATP III criteria and included 147,756 healthy participants aged 18 and above. We calculated pooled prevalence estimates and 95% confidence intervals (CI) using both fixed-effect and random-effect intercept logistic regression models. Data were analysed for 3 periods: 1996-2005, 2006-2009, and 2010-2021. The pooled prevalence of MetS in high-income countries, based on the NCEP-ATP III criteria, was 27.4% over the studied period, showing an increase from 24.2% in 1996-2005 to 31.9% in 2010-2021, with men and women having similar rates. When stratified by ethnicity and sex, ethnic minority women experienced the highest prevalence at 31.7%, while ethnic majority women had the lowest at 22.7%. Notably, MetS was more prevalent in ethnic minority women than men. Among ethnic minorities, women had a higher prevalence of MetS than men, and the difference was highest in Asians (about 15 percentage points). Among women, the prevalence of MetS was highest in Asians (41.2%) and lowest in Blacks/Africans (26.7%). Among men, it was highest in indigenous minority groups (34.3%) and lowest among in Blacks/Africans (19.8%). MetS is increasing at an alarming rate in high-income countries, particularly among ethnic minority women. The burden of MetS could be effectively reduced by tailoring interventions according to ethnic variations and risk profiles.

The Metabolic Syndrome, a Human Disease

This review focuses on the question of metabolic syndrome (MS) being a complex, but essentially monophyletic, galaxy of associated diseases/disorders, or just a syndrome of related but rather independent pathologies. The human nature of MS (its exceptionality in Nature and its close interdependence with human action and evolution) is presented and discussed. The text also describes the close interdependence of its components, with special emphasis on the description of their interrelations (including their syndromic development and recruitment), as well as their consequences upon energy handling and partition. The main theories on MS's origin and development are presented in relation to hepatic steatosis, type 2 diabetes, and obesity, but encompass most of the MS components described so far. The differential effects of sex and its biological consequences are considered under the light of human social needs and evolution, which are also directly related to MS epidemiology, severity, and relations with senescence. The triggering and maintenance factors of MS are discussed, with especial emphasis on inflammation, a complex process affecting different levels of organization and which is a critical element for MS development. Inflammation is also related to the operation of connective tissue (including the adipose organ) and the widely studied and acknowledged influence of diet. The role of diet composition, including the transcendence of the anaplerotic maintenance of the Krebs cycle from dietary amino acid supply (and its timing), is developed in the context of testosterone and β-estradiol control of the insulin-glycaemia hepatic core system of carbohydrate-triacylglycerol energy handling. The high probability of MS acting as a unique complex biological control system (essentially monophyletic) is presented, together with additional perspectives/considerations on the treatment of this 'very' human disease.

Abdominal Obesity and Mobility Disability in Older Adults: A 4-Year Follow-Up the International Mobility in Aging Study

BACKGROUND

Abdominal obesity is related to the disability process in older adults, however, little is known about this relationship when adjusted for important confounders such as depression and physical performance measures in a diverse international aged population.

OBJECTIVES

To explore the longitudinal relationship between abdominal obesity and mobility disability controlling for physical performance and depression.

DESIGN AND SETTING

Longitudinal observational study using data from the International Mobility in Aging Study (IMIAS) Study.

PARTICIPANTS

1104 out of 2002 older adults aged 64-74 years old free of mobility disability at baseline (2012) and then reassessed in 2016.

MEASUREMENTS

Mobility disability was defined as reporting difficulty in walking 400 m or climbing stairs. Activities of daily living (ADL) disability was based on any self-reported difficulty in five mobility-related ADLs. Abdominal obesity was defined as waist circumference ≥ 88cm for women or ≥ 102 cm for men. Four meters gait speed, handgrip strength and depressive symptoms (CES-D) were assessed. Generalized Estimating Equations (GEE) and multinomial regressions were used to estimate associations between disability and abdominal obesity.

RESULTS

1104 free of disability participants were followed over 4 years, the mean age was 68.9 (±2.9) years among men and 68.7 (±2.6) years among women. Prevalence and incidence rates of mobility disability varied widely across research site and sex. The longitudinal associations between mobility disability and abdominal obesity remained significant even when adjusted by depressive symptoms, handgrip strength, gait speed, age, sex, education and research site. Participants with abdominal obesity had higher mobility disability (OR=1.68, 95% CI 1.23-1.76, p-value=0.01) and also increased risk for ADL disability (OR: 1.47, 95% CI 1.23-1.76, p-value=0.01). Abdominal obesity in baseline was also predictor of mobility disability in 2016 (OR: 1.93, 95% CI 1.17-3.17, p-value <0.01) but not for ADL disability (OR: 1.59, 95% CI 0.93-2.71, p-value =0.09) with accounting mortality.

CONCLUSION

Abdominal obesity is associated longitudinally and predicts mobility disability, even over a short period (4 years) in community-dwelling older adults from different epidemiological contexts.

Diet quality indices in relation to metabolic syndrome in an Indigenous Cree (Eeyouch) population in northern Québec, Canada

Objective

To assess associations between three diet quality indices and metabolic syndrome (MetS) in the Cree (Eeyouch) of northern Québec, Canada, as well as to evaluate their pertinence in this Indigenous context.

Design

The alternative-Healthy Eating Index 2010 (aHEI-2010), the Food Quality Score (FQS) and the contribution of ultra-processed products (UPP) to total daily dietary energy intake using the NOVA classification were calculated from 24 h food recalls. MetS was determined with the latest harmonized definition. Logistic regressions assessed the relationship between quintiles of dietary quality scores with MetS and its components.

Setting

Study sample from the 2005–2009 cross-sectional Nituuchischaayihititaau Aschii Environment-and-Health Study.

Subjects

Eeyouch (n 811) from seven James Bay communities (≥18 years old).

Results

MetS prevalence was 56·6 % with 95·4 % abdominal adiposity, 50·1 % elevated fasting plasma glucose, 43·4 % hypertension, 38·6 % elevated TAG and 44·5 % reduced HDL cholesterol. Comparing highest and lowest quintiles of scores, adjusted OR (95 % CI) of MetS was 0·70 (0·39, 1·08; P-trend=0·05) for aHEI-2010, 1·06 (0·63, 1·76; P-trend=0·87) for FQS and 1·90 (1·14, 3·17; P-trend=0·04) for the contribution of UPP to total daily dietary energy intake.

Conclusions

Although diet quality indices have been associated with cardiometabolic risk, only the dietary intake of UPP was significantly associated with MetS in the Eeyouch. Indices tailored to the food environment of northern communities are essential to further understand the impact of diet quality in this context.

Omega-3 polyunsaturated fatty acid profiles and relationship with cardiometabolic risk factors in Cree (Eeyouch) of Northern Québec

Background

n-3 long-chain polyunsaturated fatty acids (LC-PUFAs) from fish are known modulators of cardiometabolic risk factors.

Objective

To examine fatty acids (FAs) status and the relationship between n-3 LC-PUFA and cardiometabolic risk factors in Cree participants.

Design

We analyzed data from a cross-sectional study (n=829) conducted in Cree adults (aged 18–74 years) from 7 communities of the James Bay territory of Quebec (Canada) in 2005–2009. Sociodemographic, lifestyle, clinical and anthropometric data were collected. FAs were quantified in red blood cells (RBCs) under fasting conditions.

Results

A total of 89% of the participants were overweight (with 69% obesity), 33% had hypertriglyceridemia, 44% had low plasma HDL-c and 77% had fasting plasma insulin ≥90 pmol/l. Total n-3 PUFAs accounted for 6% of total FAs and were higher among older participants, while n-6 PUFAs accounted for 31% of total FAs and were higher among younger participants. According to the adjusted multiple linear regression models, n-3 LC-PUFA was associated (p<0.05) with higher total cholesterol, LDL-c and apo B-100, and was also associated (p<0.05) with lower blood glucose.

Conclusion

Overall, this study showed that n-3 LC-PUFA levels measured in the RBCs of the Cree adults are relatively low and tend towards lower levels among youth. These levels might be insufficient to offset the prevalence of cardiometabolic risk factors.

The hypertriglyceridemic-waist phenotype is associated with the Framingham risk score and subclinical atherosclerosis in Canadian Cree

BACKGROUND AND AIMS

For primary prevention of cardiovascular disease (CVD), Canadian guidelines recommend that asymptomatic Canadians with abdominal obesity undergo Framingham risk score (FRS) assessment, and that in Indigenous Peoples, indicators of metabolic syndrome also be used to identify at-risk individuals. The hypertriglyceridemic-waist phenotype (HTGW) has been proposed to be a surrogate marker of visceral obesity and a simple proxy measure for metabolic syndrome. The primary aim of this study was to evaluate whether the HTGW and the FRS associated with sub-clinical atherosclerosis.

METHODS AND RESULTS

Asymptomatic Cree participants in a cross-sectional study conducted 2005-2009 (n = 446, 18-81 y) were assessed for the HTGW using NCEP-ATP-III gender-specific-cutoffs (waist circumference: for men, ≥102 cm; for women ≥88 cm) and fasting triglycerides ≥1.7 mmol/L. Sub-clinical atherosclerosis was defined by the presence of a high sex-specific common-carotid-intimal-medial-wall-thickness (≥75th percentile). HTGW was present in 26.7% and a 10-y FRS greater than 10% was present in 18.8% of participants. The multivariate adjusted OR (95% CI) for sub-clinical atherosclerosis associated with an FRS greater than 10% was 4.10 (2.20-7.50) while that associated with the HTGW phenotype was 1.74 (95% CI 1.61-1.88) from a model including age, body mass index, alcohol consumption, FRS and the HTGW.

CONCLUSIONS

The HTGW phenotype is prevalent in the Cree. Our findings support further study on the utility of combining the HTGW with the FRS in the prediction of cardiovascular disease outcomes and in health screening and intervention programs among indigenous peoples.

Anthropometric parameters and their associations with cardio-metabolic risk in Chinese working population

BACKGROUND

There remains controversy regarding which of the anthropometric indicators best defines obesity. In this study, we compared the efficacy of using body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) in the diagnosis of obesity and assessed their associations with diabetes, hypertension, and dyslipidemia in an urban working population in China.

METHODS

Anthropometric measurements, blood pressure, plasma lipids, fasting and 2-hour plasma glucose (PG) levels by a 75 gram oral glucose tolerance test (OGTT) were obtained from 2603 working Chinese who had no history of cardiovascular diseases or diabetes. Cardio-metabolic risk factors including high blood pressure, dyslipidemia, and glucose intolerance were evaluated. The diagnoses of overweight and obesity were based on the WHO definitions with BMI for general obesity and WC and WHR for central obesity.

RESULTS

Based on BMI, WC and WHR, there were 31.3%, 16.6%, 35.2% of the studied subjects, respectively, being overweight and 2.0%, 5.6%, 9.2% being obese. Among women but not men, more overweight and obese subjects were diagnosed using WHR and WC. The number of cardio-metabolic risks was higher by WC criterion than BMI and WHR in the whole group (p <0.05) and female subjects (p <0.01). Comparing the three anthropometric indexes predicting hypertension, hyperglycemia, dyslipidemia and multiple cardio-metabolic risks, for women, it was WC having the largest areas under ROC curves (0.759, 0.746, 0.701 and 0.773 respectively); while in men, it was WC for hypertension, WHR for hyperglycemia, BMI for dyslipidemia and WC for multiple cardio-metabolic risks (areas under ROC curves were 0.658, 0.686, 0.618 and 0.695 respectively).

CONCLUSIONS

Among Chinese working population, the need of lower cutoff values to define overweight and obesity were observed. Central obesity indicator (WC) is the preferred measure to predict the presence of cardio-metabolic risk in Chinese female subjects.

Progression from metabolically benign to at-risk obesity in perimenopausal women: a longitudinal analysis of study of women across the nation (SWAN)

BACKGROUND

Little is known about the natural history of progression from a metabolically benign overweight/obese (MBO) to at-risk overweight/obese (ARO) phenotype. Improved understanding would help clinicians focus on controlling risk factors that predispose an obese individual to progression.

METHODS

Using discrete-time proportional hazard modeling on data from the Study of Women's Health Across the Nation (SWAN), we examined the incident progression from MBO (less than two metabolic syndrome abnormalities) to ARO (two or more metabolic syndrome abnormalities) and factors associated with progression over a 7-year period.

RESULTS

Of 866 MBO women at baseline, 43% progressed to the ARO phenotype. Compared with those who remained MBO, those who progressed had higher baseline BMI and a higher prevalence of cardiometabolic abnormalities (elevated glucose, triglycerides, blood pressure and low high-density lipoprotein cholesterol). In multivariable analyses, an increase in body mass index was associated with a modest increase in the risk of progression. Although all cardiometabolic abnormalities were associated with an increased risk, the baseline impaired fasting glucose showed the strongest association with the risk of progression [hazard ratio 3.24; 95% confidence interval 2.10, 4.92; P < .001]. Physical activity played a protective role in decreasing the risk of progression [hazard ratio 0.86; 95% confidence interval 0.80, 0.92; P < .001].

CONCLUSIONS

Increasing obesity and the presence of cardiometabolic abnormalities increase the risk of progression, whereas physical activity is the only lifestyle factor protective against progression from metabolically benign to the at-risk overweight/obese phenotype, a state that is unanimously associated with an elevated risk of cardiovascular morbidity and mortality.

Serum leptin is associated with metabolic syndrome in obese Mexican subjects

BACKGROUND

The metabolic syndrome (MetS) is a cluster of metabolic abnormalities including insulin resistance, dyslipidemia, high blood pressure, and abdominal adiposity. Obese patients develop leptin resistance, and an increased waist circumference (WC) due to deposition of abdominal fat. The aim of this study was to evaluate the association between circulating leptin levels and MetS among sample adult Mexican workers.

METHOD

A total of 204 workers aged 20-56 were evaluated. Anthropometric index, blood pressure, fasting plasma glucose, and lipid profile were measured by spectrophotometric methods. Fasting insulin and leptin were measured by inmunoenzimatic methods. Furthermore, homeostasis model assessment for insulin resistance (HOMA-IR) was calculated.

RESULTS

The prevalence of MetS according to the ATP-III criteria was 33.8% and leptin concentrations were 2.5 times higher in women than men. Subjects with MetS had higher levels of leptin (26.7 ± 13.7) compared with those without MetS (20.1 ± 13.9; P <0.001). Leptin increased significantly while BMI increased as well (normal 14.0 ± 8.9, overweight 22.7 ± 11.7 and obese 31.4 ± 14.6) in addition to other variables such as WC, HDL-C, insulin levels, and HOMA index. Each component of MetS was stratified by sex and submitted by linear regression with a 95% of accuracy. The 50% and 53% of the BMI is explained by the concentration of leptin in men and women, respectively (P < 0.001).

CONCLUSION

This study found that leptin was associated with the MetS, especially in obesity and insulin resistance, indicating a high risk for university workers to develop hypertension, DM2, and cardiovascular disease.

Household crowding is associated with higher allostatic load among the Inuit

BACKGROUND

Household crowding is an important problem in some aboriginal communities that is reaching particularly high levels among the circumpolar Inuit. Living in overcrowded conditions may endanger health via stress pathophysiology. This study examines whether higher household crowding is associated with stress-related physiological dysregulations among the Inuit.

METHODS

Cross-sectional data on 822 Inuit adults were taken from the 2004 Qanuippitaa? How are we? Nunavik Inuit Health Survey. Chronic stress was measured using the concept of allostatic load (AL) representing the multisystemic biological 'wear and tear' of chronic stress. A summary index of AL was constructed using 14 physiological indicators compiled into a traditional count-based index and a binary variable that contrasted people at risk on at least seven physiological indicators. Household crowding was measured using indicators of household size (total number of people and number of children per house) and overcrowding defined as more than one person per room. Data were analysed using weighted Generalised Estimating Equations controlling for participants' age, sex, income, diet and involvement in traditional activities.

RESULTS

Higher household crowding was significantly associated with elevated AL levels and with greater odds of being at risk on at least seven physiological indicators, especially among women and independently of individuals' characteristics.

CONCLUSIONS

This study demonstrates that household crowding is a source of chronic stress among the Inuit of Nunavik. Differential housing conditions are shown to be a marker of health inequalities among this population. Housing conditions are a critical public health issue in many aboriginal communities that must be investigated further to inform healthy and sustainable housing strategies.

Diabetes and related metabolic conditions in an aboriginal cree community of quebec, Canada

OBJECTIVE

We evaluated the prevalence of type 2 diabetes, obesity and metabolic syndrome according to International Diabetes Federation criteria in the First Nations Cree community of Mistissini, Quebec.

METHODS

A cross-sectional study of 172 adults was performed as part of a broader regional environmental study.

RESULTS

Type 2 diabetes, hyperinsulinemia and abdominal obesity were documented in 20%, 70% and 91% of participants, respectively. The prevalence of metabolic syndrome was 54%, with the main profile including abnormal plasma glucose levels (60%) associated with high triacylglycerol (40%). Women displayed the highest prevalence of abdominal obesity (99%). In both sexes, waist circumference was clearly associated with other metabolic parameters, such as blood glucose and lipid profile (p<0.0001). However, a significant proportion of the population (13%), especially women, showed high waist circumference with no metabolic disturbances.

CONCLUSION

Among the Cree population of Mistissini, the results suggest that the high prevalence of abdominal obesity occurs most frequently in women, and earlier in women than in men. Subsequent metabolic disturbances associated with metabolic syndrome develop with age, supporting the core role of abdominal obesity in the cascade of events leading to diabetes and cardiovascular disease.

Obesity is associated with insulin resistance and components of the metabolic syndrome in Lebanese adolescents

Background

Prevalence of metabolic syndrome (MS) in obese adolescents has been reported to range between 18–42%, depending on country of origin, thus suggesting an ethnic-based association between obesity and MS.

Aim

This study aims to investigate the magnitude of the association between obesity, insulin resistance and components of MS among adolescents in Lebanon.

Subjects and methods

The sample included 263 adolescents at 4^th and 5^th Tanner stages of puberty (104 obese; 78 overweight; 81 normal weight). Anthropometric, biochemical and blood pressure measurements were performed. Body fat was assessed using dual-energy X-ray absorptiometry.

Results

According to International Diabetes Federation criteria, MS was identified in 21.2% of obese, 3.8% of overweight and 1.2% of normal weight subjects. The most common metabolic abnormalities among subjects having MS were elevated waist circumference (96.2%), low HDL (96.2%) and hypertriglyceridemia (73.1%). Insulin resistance was identified in all subjects having MS. Regression analyses showed that percentage body fat, waist circumference and BMI were similar in their ability to predict the MS in this age group.

Conclusions

MS was identified in a substantial proportion of Lebanese obese adolescents, thus highlighting the importance of early screening for obesity-associated metabolic abnormalities and of developing successful multi-component interventions addressing adolescent obesity.

Hypertriglyceridemic waist: a simple clinical phenotype associated with coronary artery disease in women

The aim of the present study was to compare the ability of the hypertriglyceridemic waist phenotype and the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) clinical criteria to predict coronary artery disease (CAD) risk in a sample of women. We studied 254 women among whom the presence/absence of CAD was assessed by angiography. The hypertriglyceridemic waist phenotype was defined as having both a high waist circumference (≥85 cm) and increased fasting triglyceride levels (≥1.5 mmol/L), whereas the presence of at least 3 of the 5 NCEP-ATP III criteria was used as the "reference" screening approach to identify women with the features of the metabolic syndrome. Women with hypertriglyceridemic waist were characterized by higher adiposity indices as well as by a more disturbed fasting metabolic risk profile compared with women without this phenotype. Similar differences were observed when comparing the metabolic profile of women with vs without at least 3 of the NCEP-ATP III clinical criteria. Moreover, differences in the Framingham risk score were essentially similar when women were considered at low or high risk by either hypertriglyceridemic waist or by NCEP-ATP III clinical criteria (P < .0001). Finally, both clinical phenotypes were predictive of CAD (hypertriglyceridemic waist: relative odds ratio, 2.1; 95% confidence interval, 1.1-3.8; P = .02; NCEP-ATP III clinical criteria: relative odds ratio, 2.5; 95% confidence interval, 1.4-4.6; P < .003). These results suggest that hypertriglyceridemic waist is a simple screening tool to identify women with clustering metabolic abnormalities and at increased CAD risk.

A comparison of the metabolic response to abdominal obesity in two Canadian Inuit and First Nations population

Inuit and Cree populations are known for high obesity rates despite markedly different rates of type 2 diabetes (T2DM). To document this apparent discrepancy we evaluated the impact of body size parameters and fasting insulin (FI) on several T2DM risk factors among Inuit and Cree populations (Québec, Canada). A total of 1,104 adults (≥18 years) Inuit and Cree individuals participated in a cross-sectional investigation. Interestingly, across both genders, across all levels of waist circumference (WC), Inuit showed lower levels of FI (age-adjusted, P < 0.0001) and fasting glucose (P < 0.0001) than Cree individuals. In both groups, a comparison of multi-sample structural equation models confirmed the predominant influence of WC on other traditional risk factors, compared to BMI. A preponderant direct impact of WC was observed on blood pressure (BP) parameters (P < 0.0001), high-density lipoprotein cholesterol (HDL-C) (P < 0.0001), and FI (P < 0.0001). Fasting glucose level appear to be influenced by WC via FI in both ethnic groups (P < 0.0001), while triacylglycerol (TAG) level was predominantly impacted by WC via FI, but only in Cree individuals (P < 0.0001). The main ethnic difference found was the strength of the impact of WC on FI, which was considerably higher among the Cree (λ = 2.4, P < 0.0001) than the Inuit (λ = 1.8, P < 0.0001). These results confirm the predominant role of abdominal adiposity in the complex and tenuous links of different traditional T2DM determinants. However, the ethnic difference in the impact of abdominal obesity on insulin levels across all WCs needs to be explored further.

Prevalence of metabolic syndrome in the Canadian adult population

BACKGROUND

Metabolic syndrome refers to a constellation of conditions that increases a person's risk of diabetes and cardiovascular disease. We describe the prevalence of metabolic syndrome and its components in relation to sociodemographic factors in the Canadian adult population.

METHODS

We used data from cycle 1 of the Canadian Health Measures Survey, a cross-sectional survey of a representative sample of the population. We included data for respondents aged 18 years and older for whom fasting blood samples were available; pregnant women were excluded. We calculated weighted estimates of the prevalence of metabolic syndrome and its components in relation to age, sex, education level and income.

RESULTS

The estimated prevalence of metabolic syndrome was 19.1%. Age was the strongest predictor of the syndrome: 17.0% of participants 18-39 years old had metabolic syndrome, as compared with 39.0% of those 70-79 years. Abdominal obesity was the most common component of the syndrome (35.0%) and was more prevalent among women than among men (40.0% v. 29.1%; p=0.013). Men were more likely than women to have an elevated fasting glucose level (18.9% v. 13.6%; p=0.025) and hypertriglyceridemia (29.0% v. 20.0%; p=0.012). The prevalence of metabolic syndrome was higher among people in households with lower education and income levels.

INTERPRETATION

About one in five Canadian adults had metabolic syndrome. People at increased risk were those in households with lower education and income levels. The burden of abdominal obesity, low HDL (high-density lipoprotein) cholesterol and hypertriglyceridemia among young people was especially of concern, because the risk of cardiovascular disease increases with age.

Does sitting height ratio affect estimates of obesity prevalence among Canadian Inuit? Results from the 2007-2008 Inuit Health Survey

OBJECTIVES

High sitting height ratio (SHR) is a characteristic commonly associated with Inuit morphology. Inuit are described as having short leg lengths and high trunk-to-stature proportions such that cutoffs for obesity derived from European populations may not adequately describe thresholds of disease risk. Further, high SHR may help explain the reduced impact of BMI on metabolic risk factors among Inuit relative to comparison populations. This study investigates the relationship between SHR and body mass index (BMI) in Inuit.

METHODS

Subjects are 2,168 individuals (837 males and 1,331 females) from 36 Inuit communities in the Canadian Arctic. Mean age is 42.63 ± 14.86 years in males and 41.71 ± 14.83 years in females. We use linear regression to examine the association between age, sex, height, sitting height, SHR, waist circumference (WC), and BMI. We then evaluate the efficacy of the relative sitting height adjustment as a method of correcting observed BMI to a population-standardized SHR.

RESULTS

Mean BMI is significantly higher than among non-Inuit Canadians. Obesity prevalence is high, particularly among Inuit women. In the regression, only age and WC are significant predictors of BMI. While SHR is significantly greater than that of the US population, there is substantial agreement between overweight and obesity prevalence using observed and corrected BMI.

CONCLUSIONS

We find no consistent relationship between SHR and BMI and suggest the unique anthropometric and metabolic profile observed in Inuit arise from factors not yet delineated. More complex anthropometric and imaging studies in Inuit are needed.

Hypertriglyceridemic-waist phenotype and glucose intolerance among Canadian Inuit: the International Polar Year Inuit Health Survey for Adults 2007-2008

BACKGROUND

Inuit have not experienced an epidemic in type 2 diabetes mellitus, and it has been speculated that they may be protected from obesity's metabolic consequences. We conducted a population-based screening for diabetes among Inuit in the Canadian Arctic and evaluated the association of visceral adiposity with diabetes.

METHODS

A total of 36 communities participated in the International Polar Year Inuit Health Survey. Of the 2796 Inuit households approached, 1901 (68%) participated, with 2595 participants. Households were randomly selected, and adult residents were invited to participate. Assessments included anthropometry and fasting plasma lipids and glucose, and, because of survey logistics, only 32% of participants underwent a 75 g oral glucose tolerance test. We calculated weighted prevalence estimates of metabolic risk factors for all participants.

RESULTS

Participants' mean age was 43.3 years; 35% were obese, 43.8% had an at-risk waist, and 25% had an elevated triglyceride level. Diabetes was identified in 12.2% of participants aged 50 years and older and in 1.9% of those younger than 50 years. A hypertriglyceridemic-waist phenotype was a strong predictor of diabetes (odds ratio [OR] 8.6, 95% confidence interval [CI] 2.1-34.6) in analyses adjusted for age, sex, region, family history of diabetes, education and use of lipid-lowering medications.

INTERPRETATION

Metabolic risk factors were prevalent among Inuit. Our results suggest that Inuit are not protected from the metabolic consequences of obesity, and that their rate of diabetes prevalence is now comparable to that observed in the general Canadian population. Assessment of waist circumference and fasting triglyceride levels could represent an efficient means for identifying Inuit at high risk for diabetes.

Levels of organochlorines and lipids across pregnancy, delivery and postpartum periods in women from Northern Norway

The objective of this study was to investigate changes in the levels of common organochlorines (OCs) and lipids in maternal serum during and after pregnancy. A subset of 50 pregnant women from the North Norwegian Mother-and-Child Study was included in this study. Blood samples were collected during the 2(nd) trimester and postpartum (Day 3 and 6 weeks) in different regions of Northern Norway, and were analyzed for the Arctic Monitoring and Assessment Programme (AMAP) suite of OC contaminants. During the gestational period, both lipids and wet-weight OC levels peaked at birth and were the lowest at 6 weeks postpartum. When the OC concentrations were lipid-adjusted, this peaking was no longer evident. Wet-weight concentrations of OCs appear to be driven by the physiological lipid profiles and are interpreted to constitute biomarkers of lipidemia. It is suggested that this observation may have implications for the biomonitoring of individuals at risk of Type 2 diabetes. Both age and parity were strong predictors for the OCs measured, but no consistent association with body mass index (BMI) was evident. Independent of lipid-adjustment, all compounds were positively and significantly correlated with each other (within and across the three collection time periods). The peaking of OCs during pregnancy suggests that the period spanning the last weeks of the 3(rd) trimester and the early postpartum days constitutes an optimum sampling window purely from the analytical perspective.

Waist circumference has heterogeneous impact on development of diabetes in different populations: longitudinal comparative study between Australia and Iran

AIMS

Comparing waist circumference (WC) role in diabetes risk prediction and diagnosis of metabolic syndrome (MS) in different populations.

METHODS

Population-based samples from Australia (n=9026) and Iran (n=8259) were studied in 2000 and followed for approximately 4 years. Follow-up attendance was approximately 58% and mean age was 51 vs. 47. Pearson correlations calculated between WC and other MS components. ROC for the role of WC in the prediction of incident diabetes was used.

RESULTS

Prevalences of MS (48% vs. 28%), an increased WC (58.5% vs. 54.5%), low HDL-C (35% vs. 11.2%), high triglyceride (52.2% vs. 29.6%) were significantly higher in Iran. Fasting glucose >or=5.6mmol/L was higher in Australia (26% vs. 23%). Hypertension was no different ( approximately 38%). Pearson correlations between WC and other MS components were stronger in Australians: FPG (0.32 vs. 0.2), HDL (0.47 vs. 0.16), TG (0.38 vs. 0.30) and SBP (0.38 vs. 0.36). Among women, area under ROC curve for WC as a predictor for diabetes was significantly higher for Australians (0.76 vs. 0.68, p<0.001) with no difference among men (0.69 vs. 0.71, p=0.4).

CONCLUSION

WC was more strongly related to other components of MS in Australia. Association between WC and MS or incident diabetes varies between ethnicities.