Association between nontraditional risk factors and metabolic syndrome in indigenous Argentinean schoolchildren

Whether apolipoproteins (Apos) are better cardiovascular disease (CVD) markers than metabolic syndrome (MS) is widely debated. Measurement of Apo B is standardized, simple, and inexpensive and does not require fasting. The aim of this study was to compare the ability of nontraditional CVD markers such as Apo B, Apo B/Apo A, non-high-density lipoprotein cholesterol (HDL-C), vitamin D, and homeostasis model assessment of insulin resistance (HOMA-IR) to identify children with MS.

A cross-sectional study of 355 Argentinean Koya schoolchildren (166 boys) 9.6±2.3 years old was performed in November 2011. Anthropometric measures, blood pressure, Tanner stages, and serum levels of glucose, lipids, insulin, Apo A, Apo B, and vitamin D were measured.

The prevalence of overweight/obesity was 10.7% (n=38), and that of underweight was 14.6% (n=52) using Centers for Disease Control and Prevention criteria. The prevalence of central obesity was 10.9% (38/355), high triglycerides was 11.1% (39/355), low HDL-C was 44.9% (158/355), hypertension was 12.8% (45/355), hyperglycemia was 0.3% (1/355), and MS was 4.2% (15/355). Several multiple logistic regression analyses showed that MS was significantly associated with HOMA-IR (odds ratio [OR], 3.6 [95% confidence interval (CI) 1.51-8.52]), non-HDL-C (OR, 1.03 [95% CI 1.007-1.049]), Apo B (OR, 1.06 [95% CI 1.03-1.09]), and Apo B/Apo A (OR, 78.3 [95% CI 3.67-1,674.4]) adjusted for age and gender. Furthermore, the areas under the receiver operator characteristic curves were as follows: Apo B, 0.77 (95% CI 0.63-0.90); Apo B/Apo A, 0.76 (95% CI 0.63-0.88); non-HDL-C, 0.72 (95% CI 0.57-0.85); and HOMA-IR, 0.69 (95% CI 0.49-0.90). These values indicate that these variables were acceptable predictors for MS.

This is the first study of nontraditional markers in South American Indian children. MS was associated with multiple nontraditional markers of future CVD risk such as non-HDL-C, Apo B, and Apo B/Apo A. However, Apo B was the best predictor for MS, suggesting that it could be used as a risk marker of future CVD in this community.