Reference of serum insulin level and prevalence of insulin resistance of Korean children and adolescents

Objective

This study was to examine the distribution of insulin and homeostasis model assessment of insulin resistance (HOMA-IR) and decide insulin resistance cut off of Korean children and adolescents.

Research Design and Methods

Data from 2,716 subjects (1,421 male, 1,295 female; age range, 10-20 years) in Korea National Health and Nutrition Examination Survey IV (2007–2009) were evaluated. The reference values of insulin and HOMA-IR of normal weight subjects were made according to sex, age and weight status. Insulin resistance was defined as HOMA-IR > 95 percentile. The odds ratios of metabolic syndrome and its components were assessed based on insulin resistance state.

Results

Insulin and HOMA-IR values appear to peak at age 13-14 years in male and age 12-13 years in female subjects. Female had lower fasting glucose and higher insulin (P = 0.049) than male. Thus, HOMA-IR between sex was not different (P = 0.257). Overweight and obese subjects had higher HOMA-IR compared with subjects of normal weight (3.83 [95% CI 3.64–4.02], 5.16 [95% CI 4.70–5.62], and 2.66 [2.62–2.71], respectively). The prevalence of insulin resistance in total subjects was 9.7% (male; 10.9 %, vs. female; 8.6 %). The prevalence of insulin resistance in normal-weight, overweight and obese subjects were 4.7%, 25.6%, and 47.1% respectively. Subject with insulin resistance had more metabolic syndrome (odds ratios, 18.33 [95% CI 9.62–34.94]) and its components.

Conclusions

Insulin and HOMA-IR values vary depending on sex, age, and weight status. Obesity is the most important risk factor for insulin resistance, but number of insulin resistance subject in normal-weight subject were compatible to those. This information may be useful in not only Korean but also Asian planning programs for the prevention of type 2 diabetes from childhood.