To evaluate racial/ethnic and sex differences in the relationship between metabolic syndrome (MetS) diagnosis and fasting insulin among adolescents.
We analyzed data from the National Health and Nutrition Evaluation Survey 1999–2008 for 3,693 non-Hispanic-white, non-Hispanic-black and Hispanic adolescents (12–19y). We used linear regression to evaluate differences in fasting insulin between those with and without an adolescent adaptation of ATPIII-MetS in a sex- and race/ethnicity-specific basis.
Females had higher insulin levels than males and non-Hispanic blacks and Hispanics had higher levels than non-Hispanic whites. Adolescents with MetS had higher insulin levels than those without MetS. The difference in insulin levels between those with and without MetS was greater among non-Hispanic blacks compared with non-Hispanic whites (p<0.05) but not Hispanics (p=0.10). The sensitivity of MetS for detecting elevated insulin levels was lower among non-Hispanic blacks and females compared with other ethnicities and males, respectively. Correlations between insulin and individual MetS components were similar among ethnicities.
MetS diagnosis performed more poorly in predicting elevated insulin levels among non-Hispanic blacks and among females. These data support the hypothesis that non-Hispanic blacks do not meet current criteria for MetS until they have reached a more advanced degree of insulin resistance.
Metabolic syndrome; ethnicity; insulin resistance; adolescents
The metabolic syndrome (MetS) concept is widely used in public health and clinical settings without an agreed pathophysiology. We have re-examined the MetS in terms of body fuels, so as to provide a coherent cross-cultural pathogenesis.
National Health and Nutrition Examination Survey (NHANES 2001-2) with n = 2254 and Taiwanese National Health Interview Survey (NHIS) sub-set for hypertension, hyperglycemia and hyperlipidemia assessment (TwSHHH 2002), n = 5786, were used to compare different ethnicities according to NCEP-ATPIII (NCEP-tw) criteria for METS. Exploratory factor analysis (EFA) using principal components (PC) was employed to differentiate and unify MetS components across four ethnicities, gender, age-strata, and urban-rural settings.
The first two factors from the PC analysis (PCA) accounted for from 55.2% (non-Hispanic white) to 63.7% (Taiwanese) of the variance. Rotated factor loadings showed that the six MetS components provided three clusters: the impaired energy regulation (IER) components (waist circumference, WC, fasting triglycerides, TG, and fasting plasma glucose, FPG), systolic and diastolic blood pressures (BPs), and HDL-cholesterol, where the IER components accounted for 25-26% of total variance of MetS components. For the three US ethnic subgroups, factor 1 was mainly determined by IER and HDL-cholesterol, and factor 2 was related to the BP components. For Taiwanese, IER was determinant for both factors, and BPs and HDL-cholesterol were related to factors 1 and 2 respectively.
There is a MetS core which unifies populations. It comprises WC, TG and FPG as a core, IER, which may be expressed and modulated in various second order ways.
Whereas it is known that the metabolic syndrome (MetS) has a paradoxically lower prevalence in non–Hispanic black adolescents than in non–Hispanic whites or Hispanics, the relative severity of MetS by race/ethnicity is unknown. Inflammation, indicated by high-sensitivity C-reactive protein (hsCRP), is a key factor linking MetS to cardiovascular disease and type 2 diabetes. Our goal was to determine whether elevations of hsCRP vary by race/ethnicity among adolescents with MetS.
RESEARCH DESIGN AND METHODS
We used the National Health and Nutrition Examination Survey (1999–2008) and evaluated adolescents (age 12–19 years) using a pediatric/adolescent adaptation of the ATP III definition of MetS. We used linear regression to evaluate the interaction between MetS status and ethnicity with respect to hsCRP concentration.
For male and female adolescents, MetS was associated with elevated hsCRP levels compared with adolescents without MetS. However, the elevation in hsCRP between adolescents with and without MetS was greater in non–Hispanic blacks compared with that in non–Hispanic whites (P = 0.04) but not that in Hispanics (P = 0.18). hsCRP concentrations correlated with individual MetS components similarly among all ethnicities. In an evaluation of adolescents diagnosed with MetS, non–Hispanic blacks had higher BMI and more hypertension than other ethnicities but there were no other racial/ethnic differences in the features of MetS.
Non–Hispanic black adolescents have a greater differential in hsCRP between those with and those without MetS than the differential in non–Hispanic whites but not that in Hispanics. Therefore, even though MetS has a low prevalence in non–Hispanic blacks, MetS is a particularly good indicator of inflammation in non–Hispanic black adolescents.
Among adolescents uric acid is associated with insulin resistance, hypertension and the metabolic syndrome (MetS) and in adults high uric acid levels are an independent risk factor for cardiovascular disease and diabetes.
Determine whether the relationship of uric acid with MetS varies in adolescents by race/ethnicity and gender.
We used linear regression to evaluate associations between uric acid and other MetS-associated clinical and laboratory measures among 3,296 non-Hispanic-white, non-Hispanic-black and Hispanic adolescents age 12–19y participating in the National Health and Nutrition Evaluation Survey (1999–2006).
Overall, non-Hispanic-white males and females had the highest uric acid levels among the three racial/ethnic groups. In each racial/ethnic group there were higher uric acid levels for those adolescents with vs. without MetS. However, the extent of the MetS-related increase in uric acid level varied by race and gender. Among males, MetS was associated with the greatest increases in uric acid among non-Hispanic whites. However, among females, the MetS-related increase in uric acid was greatest among non-whites. Non-Hispanic-white females exhibited the lowest degrees of correlation between levels of uric acid and MetS-associated variables. Uric acid levels did not correlate with insulin levels in non-Hispanic-white females.
These data suggest the relationship between uric acid and MetS varies by race/ethnicity and gender. In particular, non-Hispanic-white males exhibit a strong relationship and non-Hispanic-white females exhibit a relatively poor correlation between uric acid and MetS-related factors. These data may have implications for the use of uric acid as a marker of future risk among adolescents.
obesity; insulin resistance; hypertension
Background. Metabolic syndrome (MetS) includes five chronic disease risk factors which doubles the risk of CVD and increases the risk of diabetes fivefold. Objective. To determine the prevalence of MetS and its risk factors in Canadians (12–79 y) and to compare the dietary intake in Canadians with MetS and without MetS. Subjects and Methods. Cycle 1 of Canadian health measures survey, CHMS data, 2007–2009, was used. To identify MetS cases, the most recent criteria were used for adults and adolescents. Ethnical cut points for waist measurement were applied for adults. Results and Conclusion. The prevalence of MetS among 12–79 y Canadians was 18.31% with the lowest prevalence in adolescents (3.50%). Using ethnical cut points to define abdominal obesity increased the prevalence of MetS by 0.5% in adults. The most prevalent defining component of MetS in Canadians identified with MetS was abdominal obesity. Reduced HDL-C was equally prevalent among adolescents. Canadians with MetS consumed significantly more diet soft drinks, but less dairy products, dietary fat, and sugar-sweetened beverages compared to Canadians without MetS. Known cases of diabetes with MetS had healthier beverage choices compared to individuals without the diagnosis of diabetes, indicating adherence to nutrition recommendations.
Rationale: Metabolic syndrome (MetS) affects 4 to 10% of adolescents. Risk factors include overweight, male sex, and Hispanic ethnicity. Although sleep-disordered breathing (SDB) has been implicated as a risk factor for MetS in adults, its association with SDB in adolescents is unknown.
Objectives: To define the association of SDB with MetS in adolescents.
Methods: Standardized measurements of SDB, anthropometry and bioassays, were made in 270 adolescents, aged 13.6 ± 0.7 years. MetS was identified if threshold levels were exceeded in three of five areas: waist circumference, blood pressure, triglyceride level, high-density lipoprotein cholesterol level, and glucose levels.
Measurements and Main Results: Although 70% of children with SDB (apnea–hypopnea index ⩾ 5) were overweight and 59% had MetS, 16% of children without SDB had MetS. Twenty-five percent of those with MetS had SDB. After adjusting for age, race, sex, and preterm status, children with SDB had a 6.49 (95% confidence interval, 2.52, 16.70) increased odds of MetS compared with children without SDB. Indices of SDB stress associated with MetS included respiratory event frequency, degree of oxygen desaturation, and sleep efficiency. Analyses of individual metabolic parameters showed that, after adjustment for body mass index, SDB was associated with systolic and diastolic blood pressure, low-density lipoprotein cholesterol, and fasting insulin levels.
Conclusions: A majority of adolescents with SDB are overweight and meet criteria for MetS. The close association between MetS and SDB and their putative interacting pathophysiologies suggests a need to develop screening, prevention, and treatment strategies for both disorders in high-risk, overweight adolescents.
sleep apnea; metabolic syndrome; obesity
Information on the distribution of Metabolic syndrome (MetS) and its combinations by urban/rural areas in lower-middle income countries has been limited. It is not clear how the various combinations of MetS components varied by urban/rural population and if particular combinations of MetS are more common. This study aimed to estimate the prevalence of MetS and combinations of MetS components according to sex and urban/rural areas from a nationally representative sample of Thai adults.
Data from the fourth National Health Examination Survey of 19,256 Thai adults aged 20 years and over were analyzed. MetS was defined using the harmonized criteria of six international expert groups with Asian-specific cut-point for waist circumference.
The prevalence of MetS was 23.2% among adults aged ≥ 20 years (19.5% in men and 26.8% in women). Among men, the prevalence of MetS in urban was higher than those in rural areas (23.1% vs 17.9%, P < 0.05), but among women, the prevalence was higher in rural areas (27.9% vs 24.5%, P < 0.05). Overall, an individual component of low high density lipoprotein (HDL) and hypertriglyceridemia were more common in rural areas, while obesity, high blood pressure and hyperglycemia were more common in urban areas. The most common combination of MetS components in men was the clustering of low HDL, hypertriglyceridemia, and high blood pressure (urban: 3.4% vs. rural: 3.9%, adjusted OR 0.9, 95%CI 0.7, 1.1). Among women, the most common combination was the clustering of obesity, low HDL, and hypertriglyceridemia (urban: 3.9% vs rural: 5.9%, adjusted OR 0.8, 95%CI 0.6, 0.9), followed by the clustering of these three components with high blood pressure (urban: 3.1% vs. rural 4.5%, adjusted OR 0.8, 95%CI 0.7, 0.9).
Metabolic syndrome affects both urban and rural population with different pattern of MetS combinations. Dyslipidemia and obesity were the most common components among women in rural areas, hence, interventions to prevent and control these factors should be strengthened.
The metabolic syndrome (MetS) is a risk factor for diabetes, stroke, myocardial infarction, and increased mortality, and has been associated with cognition in some populations. We hypothesized that MetS would be associated with lower Mini-Mental State Examination (MMSE) scores in a multi-ethnic population, and that MetS is a better predictor of cognition than its individual components or diabetes.
We conducted a cross-sectional analysis among 3,150 stroke-free participants. MetS was defined by the modified National Cholesterol Education Program guidelines-Adult Treatment Panel III (NCEP-ATPIII) criteria. Linear regression and polytomous logistic regression estimated the association between MMSE score and MetS, its individual components, diabetes, and inflammatory biomarkers.
MetS was inversely associated with MMSE score (unadjusted β = −0.67; 95% CI −0.92, −0.41). Adjusting for potential confounders, MetS was associated with lower MMSE score (adjusted β = −0.24; 95% CI −0.47, −0.01), but its individual components and diabetes were not. Those with MetS were more likely to have an MMSE score of <18 than a score of ≥24 (adjusted OR = 1.94; 95% CI 1.26, 3.01). There was an interaction between MetS and race-ethnicity, such that MetS was associated with lower MMSE score among non-Hispanic whites and Hispanics but not non-Hispanic blacks.
MetS was associated with lower cognition in a multi-ethnic population. Further studies of the effect of MetS on cognition are warranted, and should account for demographic differences.
Cognitive performance; Cognitive impairment; Vascular dementia; Vascular cognitive impairment; Cerebrovascular disorders; Metabolic syndrome
Aim. At present, little data exist about incidence and the risk factors associated with metabolic syndrome (MetS) in patients with type 2 diabetes mellitus (T2DM). The objectives of present study were to assess the incidence and risk factors of MetS in people with T2DM. Methods. During the mean (SD) follow-up period of 11.7 (4.8) years, 3,047 patients with T2DM and free of MetS at baseline have been examined to determine incidence and predictors of progression to MetS. A modified the National Cholesterol Education Program—Adult Treatment Panel III definition with body mass index (BMI) instead of waist circumference was used for the MetS. Results. The prevalence of MetS was 63.2% (95% CI: 62.3, 64.1). The incidence of MetS was 28.5 (95% CI: 26.8, 30.2) (25.9 men and 30.9 women) per 1,000 patient-years based on 35,677 patient-years of follow-up. Multivariate analysis revealed that higher BMI and education, lower HbA1c and treatment with oral agent or insulin were associated with MetS. Conclusion. These are the first estimate of incidence and risk factors of MetS in patients with T2DM in Iran. These findings showed that the natural course of MetS is dynamic. The clinical management of patients with T2DM will contribute significantly to MetS prevention.
This study tests hypotheses of one-, two-, three-, and four-factor models of metabolic syndrome (MetS) components and assesses the consistency and fit of the factor models ten years later using confirmatory factor analysis in a large biracial sample of men and women.
Using data from the baseline and year-10 exams of the Coronary Artery Risk Development in Young Adults Study, confirmatory factor analysis was performed overall and for race-sex specific groups for one-, two-, three-, and four-factor MetS models in 3,403 White and Black, men and women at baseline and 2,532, ten years later. Metabolic risk variables used in the factor analysis were insulin resistance (HOMA-IR), fasting glucose, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, systolic and diastolic blood pressure, waist circumference, waist-hip ratio, triceps skin-folds, and uric acid.
Three- and four-factor models of MetS achieved excellent fits of the data, ranging from 0.92 to 0.96, for race-sex specific models and from the baseline to year-10 exams.
The results suggest that MetS factors are consistent across time and race-sex groups. When investigating the MetS, it is necessary to evaluate race-sex groups.
Metabolic Syndrome; Factor Analysis; CARDIA
Evaluation of metabolic syndrome (MetS) characteristics across an age spectrum from childhood to adulthood has been limited by a lack of consistent MetS criteria for children and adults and by a lack of adjustment for environmental factors. We used the pediatric and adult International Diabetes Federation (IDF) criteria to determine whether gender- and race-specific differences in MetS and its components are present in adolescents as in adults after adjustment for socioeconomic status (SES) and lifestyle factors.
Waist circumference, blood pressure, triglycerides, HDL cholesterol, and fasting glucose measures were obtained from 3,100 adolescent (12-19y) and 3,419 adult (20-69y) non-Hispanic white, non-Hispanic black, and Mexican-American participants of the 1999-2006 National Health and Nutrition Examination Surveys. We compared odds of having MetS and its components across racial/ethnic groups by age group, while adjusting for income, education, physical activity and diet quality.
After adjusting for possible confounding influences of SES and lifestyle, non-Hispanic-black adolescent males exhibited a lower odds of MetS and multiple components (abdominal obesity, hypertriglyceridemia, low HDL, hyperglycemia) compared to non-Hispanic-white and Mexican-American adolescents. Compared to non-Hispanic white adolescent males, Mexican-American adolescent males had less hypertension. There were no differences in MetS prevalence among adolescent females, though non-Hispanic-black girls exhibited less hypertriglyceridemia.
Racial/ethnicity-specific differences in MetS and its components are present in both adolescence and adulthood, even after adjusting for environmental factors. These data help strengthen arguments for developing racial/ethnic-specific MetS criteria to better identify individuals at risk for future cardiovascular disease.
metabolic syndrome; adolescence; insulin; race
South Asia is home to one of the largest population of people with metabolic syndrome (MetS). The prevalence of MetS in South Asians varies according to region, extent of urbanization, lifestyle patterns, and socioeconomic/cultural factors. Recent data show that about one-third of the urban population in large cities in India has the MetS. All classical risk factors comprising the MetS are prevalent in Asian Indians residing in India. The higher risk in this ethnic population necessitated a lowering of the cut-off values of the risk factors to identify and intervene for the MetS to prevent diabetes and cardiovascular disease. Some pharmacological and nonpharmacological interventions are underway in MetS to assess the efficacy in preventing the diabetes and cardiovascular disease in this ethnic population.
Metabolic syndrome; South Asians; prediabetes
To compare the use of GHb and fasting plasma glucose (FPG) to define the metabolic syndrome (MetS).
RESEARCH DESIGN AND METHODS
Data from the U.S. National Health and Nutrition Examination Survey 1999–2006 were used. MetS was defined using the consensus criteria in 2009. Raised blood glucose was defined as either FPG ≥100 mg/dl (5.6 mmol/l) or GHb ≥5.7%.
In 2003–2006, there was 91.3% agreement between GHb and FPG when either was used to define MetS. The agreement was good irrespective of age, sex, race/ethnicity, BMI, and diabetes status (≥87.4%). Similar results were found in 1999–2002. Among subjects without diabetes, only the use of GHb alone, but not FPG, resulted in significant association with cardiovascular diseases (odds ratio 1.45, P = 0.005).
Using GHb instead of FPG to define MetS is feasible. It also identifies individuals with increased cardiovascular risk.
Background. The NCEP metabolic syndrome (MetS) is a combination of dichotomized interrelated risk factors from predominantly Caucasian populations. We propose a continuous MetS score based on principal component analysis (PCA) of the same risk factors in a multiethnic cohort and compare prediction of incident CVD events with NCEP MetS definition. Additionally, we replicated these analyses in the Health, Aging, and Body composition (Health ABC) study cohort. Methods and Results. We performed PCA of the MetS elements (waist circumference, HDL, TG, fasting blood glucose, SBP, and DBP) in 2610 Caucasian Americans, 801 Chinese Americans, 1875 African Americans, and 1494 Hispanic Americans in the multiethnic study of atherosclerosis (MESA) cohort. We selected the first principal component as a continuous MetS score (MetS-PC). Cox proportional hazards models were used to examine the association between MetS-PC and 5.5 years of CVD events (n = 377) adjusting for age, gender, race, smoking and LDL-C, overall and by ethnicity. To facilitate comparison of MetS-PC with the binary NCEP definition, a MetS-PC cut point was chosen to yield the same 37% prevalence of MetS as the NCEP definition (37%) in the MESA cohort. Hazard ratio (HR) for CVD events were estimated using the NCEP and Mets-PC-derived binary definitions. In Cox proportional models, the HR (95% CI) for CVD events for 1-SD (standard deviation) of MetS-PC was 1.71 (1.54–1.90) (P < 0.0001) overall after adjusting for potential confounders, and for each ethnicity, HRs were: Caucasian, 1.64 (1.39–1.94), Chinese, 1.39 (1.06–1.83), African, 1.67 (1.37–2.02), and Hispanic, 2.10 (1.66-2.65). Finally, when binary definitions were compared, HR for CVD events was 2.34 (1.91–2.87) for MetS-PC versus 1.79 (1.46–2.20) for NCEP MetS. In the Health ABC cohort, in a fully adjusted model, MetS-PC per 1-SD (Health ABC) remained associated with CVD events (HR = 1.21, 95%CI 1.12–1.32) overall, and for each ethnicity, Caucasian (HR = 1.24, 95%CI 1.12–1.39) and African Americans (HR = 1.16, 95%CI 1.01–1.32). Finally, when using a binary definition of MetS-PC (cut point 0.505) designed to match the NCEP definition in terms of prevalence in the Health ABC cohort (35%), the fully adjusted HR for CVD events was 1.39, 95%CI 1.17–1.64 compared with 1.46, 95%CI 1.23–1.72 using the NCEP definition. Conclusion. MetS-PC is a continuous measure of metabolic syndrome and was a better predictor of CVD events overall and in individual ethnicities. Additionally, a binary MetS-PC definition was better than the NCEP MetS definition in predicting incident CVD events in the MESA cohort, but this superiority was not evident in the Health ABC cohort.
To evaluate whether in hypertensive patients the risk of cardiovascular disease is greater in association with the metabolic syndrome (MetS) or the sum of its individual components.
RESEARCH DESIGN AND METHODS
Cox regression analysis models were developed to assess the influence of age, sex, ethnicity, and the individual components of MetS on risk associated with the MetS (using several definitions) of coronary outcomes, stroke, and all-cause mortality.
MetS was significantly associated with coronary outcomes, stroke, and all-cause mortality after adjusting for age, sex, and ethnicity. However, when the model was further adjusted for the individual components, MetS was associated with significantly increased risk of stroke (hazard ratio 1.34 [95% CI 1.07–1.68]) and all-cause mortality (1.35 [1.16–1.58]) but not coronary outcomes (fatal coronary heart disease plus nonfatal myocardial infarction 1.16 [0.95–1.43] and total coronary events 1.06 [0.91–1.24]).
MetS, independent of its individual components, is associated with increased risk of stroke and all-cause mortality but not coronary outcomes.
The metabolic changes present in the metabolic syndrome (MetS) have been associated with increased risk of pancreatic and colon cancers; however, there is little information about the association between MetS and cervical cancer risk. We performed a case-control study using data from the National Health and Nutrition Examination Survey (NHANES) between 1999–2010. We identified women 21 years of age and older, of which an estimated 585,924 (2.3% of the sample) self-reported a history of cervical cancer (cases). About half (48.6%) of cases and 33.2% of controls met criteria for MetS. Logistic regression analysis showed increased odds of history of cervical cancer among women with MetS (OR = 1.9; 95% CI 1.06, 3.42; P value ≤ 0.05) for the risk of history of cervical cancer among women with MetS while adjusting for other known risk factors (high number of lifetime sexual partners, multiparty, history of hormonal contraceptive use, and history of smoking) (AOR = 1.82; 95% CI 1.02, 3.26; P value ≤ 0.05). In this US surveyed population we found increased odds of history of cervical cancer among subjects with MetS.
Background and aims
Metabolic syndrome (MetS) comprises central obesity, insulin resistance, hypertension and dyslipidemia, interrelated metabolic risk factors for diabetes and cardiovascular disease. A state of low-grade systemic inflammation may underlie this constellation of risk factors. Chronic inflammatory conditions, such as periodontal disease, may contribute to systemic inflammation and development of MetS. This study examines the association of periodontitis with MetS with and without consideration of systemic inflammatory status.
The association of alveolar bone loss (none/slight vs moderate/severe) determined from panoramic radiographs and MetS parameters were analyzed using logistic regression, adjusting for age, sex, ethnicity, and smoking in 112 men and 78 women (mean±SD age 56.7±13.3 and 60.0±12.1, respectively) participating in the Baltimore Longitudinal Study of Aging.
Participants with radiographic evidence of moderate to advanced alveolar bone loss were significantly more likely to have MetS than those with minimal or no bone loss (OR 2.61, 95% CI 1.1–6.1, p<0.05). No significant differences in systemic inflammation were found between periodontal groups.
The association of alveolar bone loss to MetS is consistent with the hypothesis that destructive periodontal disease may contribute to the development of MetS and elevations in systemic inflammation. Longitudinal studies are necessary to clarify the role of periodontal disease in the development of MetS and conditions associated with chronic inflammation.
Inflammation; metabolic syndrome; obesity; periodontal disease; periodontitis
Obesity is closely associated with chronic diseases such as hypertension, type 2 diabetes mellitus (T2DM), and dyslipidemia. We analyzed the optimal obesity index cut-off values for metabolic syndrome (MetS), and identified the obesity index that is more closely associated with these chronic diseases, in a population of northern Chinese.
We surveyed 8940 adults (age, 20–74 years) living in northern China for chronic diseases. Receiver operating characteristics (ROC) analysis, relative risk, and multivariate regression were used to develop an appropriate index and optimal cut-off values for MetS and obesity-related chronic diseases.
Waist circumference (WC) and body mass index (BMI) were good markers for MetS, WC was a good marker for T2DM and dyslipidemia, and BMI was a good marker for hypertension. The optimal BMI cut-off value of MetS was 24 kg/m2, and the optimal WC cut-offs were 86 cm and 78 cm in men and women, respectively. Relative risk regression models showed that BMI was associated with hypertension, T2DM, and hypertriglyceridemia and a higher prevalence ratio (PR) for hypertension: 2.35 (95% CI, 2.18–2.50). WC was associated with T2DM, hypertension, and hypertriglyceridemia, with PRs of 2.05 (1.63–2.55) for T2DM and 2.47 (2.04–2.85) for hypertriglyceridemia. In multivariate regression models, the standardized regression coefficients (SRCs) of BMI were greater for SBP and DBP, and the SRC of WC was greater for fasting blood glucose, 2-hour postload blood glucose, triglyceride, and total cholesterol.
Our analysis of a population of northern Chinese indicates that the optimal cut-off values for MetS are WCs of 86 cm in men and 78 cm in women and a BMI of 24 kg/m2 in both sexes. BMI was strongly associated with hypertension, while WC was strongly associated with T2DM and dyslipidemia.
obesity; chronic disease; cut-off value
The proposed waist-to-height ratio (WHtR) cut-off of 0.5 is less optimal for cardiometabolic risk screening in children in many settings. The purpose of this study was to determine the optimal WHtR for children from South Africa, and investigate variations by gender, ethnicity and residence in the achieved value.
Metabolic syndrome (MetS) components were measured in 1272 randomly selected learners, aged 10–16 years, comprising of 446 black Africans, 696 mixed-ancestry and 130 Caucasians. The Youden’s index and the closest-top-left (CTL) point approaches were used to derive WHtR cut-offs for diagnosing any two MetS components, excluding the waist circumference.
The two approaches yielded similar cut-off in girls, 0.465 (sensitivity 50.0, specificity 69.5), but two different values in boys, 0.455 (42.9, 88.4) and 0.425 (60.3, 67.7) based on the Youden’s index and the CTL point, respectively. Furthermore, WHtR cut-off values derived differed substantially amongst the regions and ethnic groups investigated, whereby the highest cut-off was observed in semi-rural and white children, respectively, Youden’s index0.505 (31.6, 87.1) and CTL point 0.475 (44.4, 75.9).
The WHtR cut-off of 0.5 is less accurate for screening cardiovascular risk in South African children. The optimal value in this setting is likely gender and ethnicity-specific and sensitive to urbanization.
This study was designed to investigate the correlations of knee osteoarthritis (OA) with metabolic syndrome (MetS) and MetS parameters in Korean subjects.
This study included data from 270 subjects with knee OA and 1964 control subjects with a mean age of 54.56 (SD 11.53) years taken from the Korean National Health and Nutritional Examination Survey (KNHANES) 2008. Multivariate logistic regression analysis was conducted to examine possible associations for knee OA with MetS and MetS parameters.
MetS was shown to be associated with an increased risk of knee OA in female subjects in unadjusted analysis (OR 1.798, 95% CI 1.392, 2.322), but this significance disappeared when adjusted for confounding factors (OR 1.117, 95% CI 0.805, 1.550). No significant association between MetS and knee OA was found in male subjects. Among parameters of MetS, only high waist circumference (WC) in female subjects was significantly associated with an increased prevalence of knee OA, even after adjusting for confounding factors, while no other significant associations were found in both male and female subjects.
We found that WC was associated with knee OA in female subjects, but neither MetS nor any parameters thereof were shown to be associated with knee OA in the Korean subjects of this study. Although we found no relationship between a pre-inflammatory state of MetS and knee OA, we believe further investigation of this relationship in various aspects is warranted, as MetS may also be a risk factor for complications in knee OA related procedures.
Metabolic syndrome; Knee; Osteoarthritis
Background. Bisphenol A (BPA) is detected in the urine of >95% of US adults. Recent evidence from population-based studies suggests that BPA is associated with individual components for metabolic syndrome (MetS). However, no previous study has examined the direct association between BPA and MetS. Methods. We examined 2,104 participants from the National Health and Nutrition Examination Survey 2003–2008. The main outcome was the presence of MetS (n = 741). Results. Increasing levels of urinary BPA were positively associated with MetS, independent of confounders such as age, gender, race/ethnicity, smoking, alcohol intake, physical activity, and urinary creatinine. Compared to tertile 1 (referent), the multivariable adjusted odds ratio (95% confidence interval) of MetS in tertile 3 was 1.51 (1.07–2.12); P-trend was 0.02. Conclusions. Urinary BPA levels are positively associated with MetS, in a representative sample of US adults and independent of traditional risk factors for MetS. Future, prospective studies are needed to confirm our findings.
Metabolic syndrome (MetS) is an established concept. However, it is characterized by a number of different definitions as well as different cut-off points (COPs) for waist circumference (WC) and different modes for incorporating WC into the diagnostic criteria.
Abdominal ultrasonography was performed in 2,333 subjects who also underwent comprehensive medical examinations between April and July 2006. The odds ratios for the number of MetS components were calculated by taking central obesity status into account and considering concurrent fatty liver as an independent variable. We compared the areas under the receiver operating characteristic (ROC) curves for fatty liver and MetS using several MetS criteria.
Regardless of the WC criterion selected, we observed a strong linear trend for an association (trend P < 0.0001) between MetS and the number of components. The odds ratio (OR) of subjects without central obesity but with all three MetS components was 9.69 (95% confidence interval 3.11–30.2) in men and 55.3 (6.34–483) in women. The COP for the largest area under the curve in men and women was ≥82 cm (OR 0.701) and ≥77 cm (OR 0.699), respectively, when WC was considered as a component. When WC distribution is taken into consideration, practical and appropriate COPs should be ≥85 cm for men and ≥80 cm for women.
We suggest that a WC of ≥85 cm for men and ≥80 cm for women would be optimal COPs for the central obesity criteria in the Japanese population. In addition, central obesity should be incorporated as a component of MetS rather than an essential requirement for the diagnosis of MetS.
Central obesity; Diagnostic criteria; Metabolic syndrome; ROC curve
Current smoking is associated with type 2 diabetes mellitus and impaired glucose tolerance but its association with the metabolic syndrome (metS), particularly with sufficiently sampled African American representation, has not been clearly established.
To assess whether a) metS is associated with smoking; b) any increased risk of metS among smokers is independent of body mass index (BMI) compared with non-smokers; c) smoking status is differentially associated with the metS and its components across different ethnic groups.
Cross sectional analysis of the Multi-Ethnic Study of Atherosclerosis (MESA) a community population-based sample free of cardiovascular disease.
Current smokers (N = 769) had higher risk of metS (odds ratio [OR, 95% confidence interval]: 1.4, 1.1-1.7) versus never (reference, N = 2981) and former smokers (1.0, 0.8-1.1, N = 2163) and for metS components: high waist circumference (WC) (OR:1.9, 1.2-2.1), low high density lipoprotein cholesterol (HDL-C) (1.5, 1.3-1.8), elevated plasma triglycerides (TG) (OR:1.4, 1.2-1.7) as well as high C-reactive protein (CRP, an inflammatory marker) concentration (OR: 1.6,1.3-2.0) compared to never and former smokers after adjustment for BMI. A smoking status by ethnicity interaction occurred such that African American current and former smokers had greater likelihood of low HDL-C than White counterparts.
This study found that smoking is associated with the metS and despite the lower BMI of current smokers the prevalence of low HDL-C, elevated TG and CRP is higher among them than among non-smokers. African Americans generally have higher HDL-C than Whites but smoking wipes out this advantage.
Multi-Ethnic Study of Atherosclerosis (MESA) ClinicalTrials.gov Identifier: NCT00005487
Metabolic syndrome; Smoking; Ethnic groups; Body mass index
In 2001 the National Cholesterol Education Program (NCEP) provided a categorical definition for metabolic syndrome (c-MetS). We studied the extent to which two ethnic groups, Blacks and Whites were affected by c-MetS. The groups were members of the Hypertension Genetic Epidemiology Network (HyperGEN), a part of the Family Blood Pressure Program, supported by the NHLBI. Although the c-MetS definition is of special interest in particular to the clinicians, the quantitative latent traits of the metabolic syndrome (MetS) are also important in order to gain further understanding of its etiology. In this study, quantitative evaluation of the MetS latent traits (q-MetS) was based on the statistical multivariate method factor analysis (FA).
The prevalence of the c-MetS was 34% in Blacks and 39% in Whites. c-MetS showed predominance of obesity, hypertension, and dyslipidemia. Three and four factor domains were identified through FA, classified as "Obesity," "Blood pressure," "Lipids," and "Central obesity." They explained approximately 60% of the variance in the 11 original variables. Two factors classified as "Obesity" and "Central Obesity" overlapped when FA was performed without rotation. All four factors in FA with Varimax rotation were consistent between Blacks and Whites, between genders and also after excluding type 2 diabetes (T2D) participants. Fasting insulin (INS) associated mainly with obesity and lipids factors.
MetS in the HyperGEN study has a compound phenotype with separate domains for obesity, blood pressure, and lipids. Obesity and its relationship to lipids and insulin is clearly the dominant factor in MetS. Linkage analysis on factor scores for components of MetS, in familial studies such as HyperGEN, can assist in understanding the genetic pathways for MetS and their interactions with the environment, as a first step in identifying the underlying pathophysiological causes of this syndrome.
OBJECTIVE: To describe the association between intima-media thickness (IMT) and metabolic syndrome (MetS) and to examine if the addition of IMT to a traditional MetS definition adds value to the assessment of predicted cardiovascular disease (CVD) risk in a large multiethnic population.
PARTICIPANTS AND METHODS: In this cross-sectional study, carotid IMT was measured in 2268 men and women as part of a wellness physical examination between August 1, 2000, and October 1, 2001. The wellness examination included a fasting lipid panel, physical examination, and medical history. Mean IMT was described by sex, ethnicity, and the MetS. Predicted risk for CVD was determined with IMT as a component of the diagnostic criteria for MetS.
RESULTS: Intima-media thickness increased with each additional component of the MetS, increasing from 0.516 mm for 0 components to 0.688 mm for 4 or more components (P<.001). In each ethnic group (non-Hispanic whites, blacks, Hispanics, and Asians), those with the MetS had higher mean IMT (increased by 0.084 mm to 0.134 mm) than those without MetS. The addition of IMT as a “new” component in the diagnosis of MetS allowed us to identify 78 (3.4%) participants who were not previously diagnosed as having MetS but who had a high 10-year estimated risk of MetS as measured by the Framingham risk score (11.67%).
CONCLUSION: The addition of IMT to the traditional criteria for the diagnosis of the MetS may help identify individuals who otherwise would not have been identified to be at high risk of CVD.
This article describes the association between intima-media thickness and metabolic syndrome and concludes that the addition of intima-media thickness to the traditional criteria for the diagnosis of the metabolic syndrome may help identify individuals who otherwise would not have been identified to be at high risk of cardiovascular disease.