DECREASED INSULIN SENSITIVITY IN PREPUBERTAL GIRLS WITH PREMATURE ADRENARCHE AND ACANTHOSIS NIGRICANS

Benign premature adrenarche (PA) is the term used to refer to girls wi th the early development of pubic hair before the age of 8 yr and is c haracterized by mild hyperandrogenism. Hyperandrogenism in adult women is often not as benign and has been associated with insulin resistanc e, acanthosis nigricans (AN), and the polycystic ovary syndrome. We ha ve seen a group of young girls with PA who have also been found to hav e AN. The purpose of this study was to determine whether there are any clinical and biochemical differences in those girls with PA with and without AN. Twelve girls with PA were divided into two groups at the t ime of evaluation: group I, those without AN (n = 5); and group II, th ose with AN (n = 7). Adrenal androgen levels were determined in all su bjects by a 60-min AGTH stimulation test. Insulin sensitivity was meas ured by the frequently sampled iv glucose tolerance test with tolbutam ide and was assessed using the modified minimal model. Mean chronologi cal age, bone age, and weight for length index were similar in the two groups. The baseline and stimulated levels of adrenal androgens were also not significantly different between the two groups. The group I g irls (without AN) had an insulin sensitivity index of 6.75 +/- 1.31, w hich was in the normal prepubertal range. This was significantly diffe rent from that in group II (with AN), who had an insulin sensitivity i ndex of 3.69 +/- 1.29. Therefore, many girls with premature adrenarche can have AN and decreased insulin sensitivity. Whether these girls ha ve a truly benign course or are at risk of ovarian dysfunction or carb ohydrate intolerance needs to be assessed.