Leptin and adiponectin are two representative adipocytokines. Leptin increases, but adiponectin decreases, with obesity and insulin resistance. We aimed to study the relationship between the leptin/adiponectin ratio and insulin resistance in healthy children.

Seventy-seven healthy children (36 boys and 41 girls) were enrolled in this study. Anthropometric measurements were performed, and the percentage of weight for height (%WFH) was calculated in each subject. Fasting plasma levels of glucose, insulin, leptin, adiponectin, testosterone, estradiol, and sex-hormone binding globulin (SHBG) were measured. The free androgen index (FAI) was used as a representative of testosterone bioactivity. The homeostasis model assessment was used to estimate the degree of insulin resistance (HOMA-IR).

In the boys, HOMA-IR was significantly correlated with age, pubertal stage, free androgen index (FAI), leptin, and the leptin/adiponectin ratio. HOMA-IR was also significantly related to age, percentage of weight for height (%WFH), pubertal stage, estradiol, leptin, and the leptin/adiponectin ratio in girls. The leptin/adiponectin ratio was independently related to HOMA-IR after adjusting for age, %WFH, and FAI in the boys ( P <0.05). The leptin/adiponectin ratio was not independently related to HOMA-IR after adjusting for age, %WFH, and estradiol in girls.

In non-obese healthy children, the leptin/adiponectin ratio was significantly correlated with insulin resistance. The leptin/adiponectin ratio was independently related to insulin resistance even after adjusting for age, degree of obesity, and androgen levels in healthy boys.