Vitamin D status and premature adrenarche.

BACKGROUND

Vitamin D, an important factor in calcium-phosphate homeostasis, has recently been suggested to play an important role in the pathogenesis of numerous chronic conditions such as hyperandrogenism. The aim of this study was to investigate the relationship between vitamin D status and premature adrenarche (PA).

METHODS

A total of 71 girls with PA and 52 healthy girls, as the control group, were recruited. Axillary and/or pubic hair development before the age of 8 years was defined as PA. Bone age and anthropometric measures including height, weight, and body mass index (BMI) were obtained. 25-Hydroxyvitamin D (25(OH)D), fasting plasma glucose and insulin were measured. Vitamin D insufficiency was defined as <20 ng/mL.

RESULTS

The PA patients had older bone age, higher BMI standard deviation score, homeostasis model of assessment-insulin resistance (HOMA-IR), and androgen but lower 25(OH)D than the control group. HOMA-IR and dehydroepiandrosterone sulfate were also higher in PA patients with vitamin D insufficiency compared with those with normal vitamin D. There was a negative correlation between 25(OH)D and HOMA-IR.

CONCLUSION

Low vitamin D is associated with PA; and insulin resistance may be a factor in this association.