Educational Disparities in Distribution of Cardiovascular Risk Factors and Quality of Care in Korean Adults: Korean National Health and Nutrition Survey IV

Educational Disparities in Risk for Metabolic Syndrome

BACKGROUND

The objective of this study was to evaluate the relationship between educational level as a surrogate marker of socioeconomic status and the risk of developing metabolic syndrome (MetS).

METHODS

Study subjects were 1915 Korean adults (1193 women and 722 men) who participated in a cohort study. Educational level was categorized into two groups: (1) high education (more than 12 years of education), and (2) low education (less than 12 years of education). MetS was defined according to diagnostic criteria of the National Cholesterol Education Program (NCEP-III) and the International Diabetes Federation (IDF). Multiple logistic regression analysis and Cox proportional hazard analysis were performed to evaluate cross-sectional and prospective association between MetS or MetS components and educational level after adjusting for covariates.

RESULTS

The overall prevalence of MetS at baseline was 15.0% in women and 20.4% in men. Incidence of MetS over 4.52 years was 16.6 per 1000 person-year in women and 27.6 per 1000 person-year in men. The prevalence and incidence of MetS were higher in the low educational group than those in the high educational group in both sexes. At baseline, the risk of MetS (odds ratio [OR]: 1.63, 95% confidence interval [CI]: 1.05-2.53 for NCEP criteria; OR: 2.30, 95% CI: 1.41-3.76 for IDF criteria) and abdominal obesity (OR: 2.62, 95% CI: 1.75-3.93) were higher in less educated women compared with those in more educated women. In men, there was no association between Mets or MetS components and educational level. Over 4.6 years of follow-up, the risk of developing MetS in women in the low education group (hazard ratio [HR]: 1.95, 95% CI: 1.12-3.50 for NCEP criteria; HR: 2.36, 95% CI: 1.14-4.86 for IDF criteria) was significantly higher than that in the high education group. In men, low education significantly increased the risk of developing impaired fasting glucose (HR: 1.95, 95% CI: 1.12-3.40).

CONCLUSION

An inverse association between educational level and MetS was found in Korean women, suggesting that socioeconomic disparities might increase the risk of MetS development, especially in women.

Indicators of abdominal size relative to height associated with sex, age, socioeconomic position and ancestry among US adults

BACKGROUND/OBJECTIVES

The supine sagittal abdominal diameter (SAD) and standing waist circumference (WC) describe abdominal size. The SAD/height ratio (SADHtR) or WC/height ratio (WHtR) may better identify cardiometabolic disorders than BMI (weight/height2), but population-based distributions of SADHtR and WHtR are not widely available. Abdominal adiposity may differ by sociodemographic characteristics.

SUBJECTS/METHODS

Anthropometry, including SAD by sliding-beam caliper, was performed on 9894 non-pregnant adults ≥20 years in the US National Health and Nutrition Examination Surveys of 2011-2014. Applying survey design factors and sampling weights, we estimated nationally representative SADHtR and WHtR distributions by sex, age, educational attainment, and four ancestral groups.

RESULTS

The median (10th percentile, 90th percentile) for men's SADHtR was 0.130 (0.103, 0.165) and WHtR 0.569 (0.467, 0.690). For women, median SADHtR was 0.132 (0.102, 0.175) and WHtR 0.586 (0.473, 0.738). Medians for SADHtR and WHtR increased steadily through age 79. The median BMI, however, reached maximum values at ages 40-49 (men) or 60-69 (women) and then declined. Low educational attainment, adjusted for age and ancestry, was associated with elevated SADHtR more strongly than elevated BMI. While non-Hispanic Asians had substantially lower BMI compared to all other ancestral groups (adjusted for sex, age and education), their relative reductions in SADHtR and WHtR, were less marked.

CONCLUSIONS

These cross-sectional data are consistent with monotonically increasing abdominal adipose tissue through the years of adulthood but decreasing mass in non-abdominal regions beyond middle age. They suggest also that visceral adipose tissue, estimated by SADHtR, expands differentially in association with low socioeconomic position. Insofar as Asians have lower BMIs than other populations, employing abdominal indicators may attenuate the adiposity differences reported between ancestral groups. Documenting the distribution and sociodemographic features of SADHtR and WHtR supports the clinical and epidemiologic adoption of these adiposity indicators.