Biochemical characteristics and risk factors for insulin resistance at different levels of obesity.

OBJECTIVE

To establish the biochemical characteristics of nonobese, overweight, and obese children as well as to determine the risk factors associated with insulin resistance in nonobese children and with non-insulin resistance in obese children in the age strata of 6 to 11 years.

METHODS

A total of 3512 healthy children were enrolled in a cross-sectional study. In the absence of obesity, fasting hyperinsulinemia and hypertriglyceridemia defined nonobese, insulin-resistant (NO-IR) children. In the absence of metabolic abnormalities of fasting insulin and triglycerides levels, obese children were defined as obese, not insulin-resistant (O-NIR) children.

RESULTS

The gender- and age-adjusted prevalence of NO-IR and O-NIR was 6.6% and 21.3%, respectively. In the age-, gender-, and birth weight-adjusted analysis, family history of hypertension (FHH) in both maternal and paternal branches (odds ratio [OR]: 1.514; 95% confidence interval [CI]: 1.2-3.9; P = .04) was associated with NO-IR children. In the analysis adjusted by gender, age, waist circumference (WC), BMI, FHH, and family history of diabetes, high birth weight was associated with NO-IR children (OR: 1.319; 95% CI: 1.2-2.1; P = .04). Finally, in the gender-, age-, family history-, and birth weight-adjusted analysis, a WC lower than the 95th percentile was associated with a lower odds of insulin resistance among obese children (OR: 0.96; 95% CI: 0.91-0.98; P < .0005).

CONCLUSIONS

FHH and high birth weight are associated with NO-IR children, and a low WC is associated with lower odds of O-IR children.