Race and gender disparities in nutrient intake are not related to metabolic syndrome in 20- to 59-year-old US adults

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.

Racial/ethnic differences in the prevalence and incidence of metabolic syndrome in high-income countries: a protocol for a systematic review

BACKGROUND

Metabolic syndrome is a constellation of various cardiovascular and type 2 diabetes risk factors, such as abdominal obesity, atherogenic dyslipidemia, high blood pressure, and high blood glucose, but its prevalence varies widely by geographical region, sex, and race/ethnicity. The objective of this study is to examine the prevalence and incidence of metabolic syndrome among adults of different racial/ethnic origins in high-income countries.

METHODS

We designed and registered a study protocol for a systematic review of descriptive epidemiological data. Observational studies (e.g., cross sectional and cohort studies) reporting morbidity data of metabolic syndrome and conducted in a wide range of adult people (e.g., different racial/ethnic origins, including migrants) will be included. The primary outcome will be the prevalence and incidence of metabolic syndrome. Secondary outcomes will be the prevalence and incidence of individual components of metabolic syndrome (e.g., abdominal obesity, dyslipidemia, high blood pressure, and high blood glucose). Literature searches will be conducted in several electronic databases (from inception onwards), including MEDLINE, Web of Science Core Collection (Science Citation Index and Social Science Citation Index), CINAHL, and Cochrane Library. Two investigators will independently screen all reference titles, abstracts, and full-text articles. The methodological quality (or potential bias) of selected studies will be appraised using an appropriate tool. Our results will be described narratively. Random-effects meta-analysis will be conducted, if feasible and appropriate. Additional analyses will be conducted to explore the potential sources of heterogeneity.

CONCLUSION

This systematic review will identify, evaluate, and integrate prevalence and incidence data of metabolic syndrome, with focus on racial/ethnic differences in high-income countries. We anticipate our findings may guide policy formulation and identify knowledge gaps in the literature that future research should address.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42020157189.

Metabolic syndrome (MetS) and associated factors in middle-aged women: a cross-sectional study in Northeast Brazil

We determined the prevalence of Metabolic Syndrome (MetS) and associated factors in 419 women (aged 40 to 65 years) in Northeast Brazil in a cross-sectional study conducted from April to November 2013. We defined MetS using the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) criteria. Socio-demographic variables, reproductive factors, lifestyle factors, anthropometrics, body composition, quality of life, and physical performance were assessed for their associations. We constructed multivariate Poisson regression models to estimate prevalence rate ratios (PRR) and 95% confidence intervals (CI). We identified 275 (65.6%) cases of MetS. The three most prevalent indicators were obesity (73.5%), reduced high-density lipoprotein level (63.0%), and elevated blood pressure (60.9%). In the final adjusted model, black race (PR 1.30, 95% CI: 1.07-1.57), lower grip strength/body mass index (PR 1.31, 95% CI: 1.15-1.50), and low estradiol levels (PR 1.17, 95% CI: 1.00-1.35) were associated with MetS. MetS is a long-term threat to the health of middle-aged women and a potential public health burden. These results may help in developing health promotion strategies to prevent morbidity and mortality associated with MetS in this vulnerable population.

VITAMIN DEFICIENCY AND INSULIN RESISTANCE IN NONDIABETIC OBESE PATIENTS

OBJECTIVE

Obese people may have nutritional deficiencies, although they are exposed to excessive food intake. We aim to assess relationship of vitamin D, B12, and folic acid levels and dietary vitamin intake and insulin resistance in obese people.

DESIGN

This case-control study was performed at the obesity outpatient clinics between March 2014 and April 2015.

SUBJECTS AND METHODS

We included 304 non-diabetic obese subjects in patient group and 150 normal weight individuals in control group. Patients were questioned in detail about their food intake.

RESULTS

Mean age of obese patients was 37.3±10.1 years, the mean duration of obesity was 7.9±5.4 years, and the percentage of female patients was 65.8%. Mean vitamin D, B12, and folic acid levels were significantly lower in patients than in controls. Vitamin D deficiency (<20 ng/mL) in 69.7%, vitamin B12 deficiency (<200 pg/mL) in 13.5%, and folic acid deficiency (<4 ng/mL) was found in 14.2% of the patients. BMI negatively correlated with vitamin D, B12, and folic acid levels. B12 levels negatively correlated with duration of obesity. Insulin resistance was found in 55.9% of patients and HOMA-IR levels negatively correlated with vitamin D and B12 levels. While dietary vitamin D and folic acid intakes were inadequate in all of patients, only 28.3% of patients had inadequate vitamin B12 intake. There was no relation between vitamin levels and dietary vitamin intakes.

CONCLUSIONS

The study reveals that vitamin D, B12, and folic acid levels were low and poor vitamin D and B12 status were associated with insulin resistance in nondiabetic obese patients.