Plasma sex hormone-binding globulin and androgen levels in the management of hirsute patients.

Hirsutism in women is a manifestation of excessive androgen action. This may be due to excessive exposure, or to increased sensitivity, of peripheral tissues to androgens. The present study was undertaken to estimate the percentage of hirsute patients with hyperandrogenaemia and to examine the effect of correction of hyperandrogenaemia on the clinical presentation. Plasma testosterone, dihydrotestosterone, sex hormone-binding globulin (SHBG) and androstenedione were determined in 58 hirsute patients before and following 3 months therapy with dexamethasone, 0.5 mg nocte. Testosterone expressed as a function of SHBG (testosterone/SHBG) provides an index of the non-protein bound testosterone fraction. Plasma levels of androstenedione were significantly elevated in 28% of hirsute patients, testosterone in 31% and testosterone/SHBG was elevated in 52%. Five per cent of patients had an elevated androstenedione value together with a normal testosterone/SHBG value. A subgroup of 13 hirsute patients with oligomenorrhoea had significantly higher values for androstenedione and testosterone/SHBG than eumenorrhoeic hirsute patients, and plasma testosterone, androstenedione and testosterone/SHBG values were more frequently elevated. In hirsute patients dexamethasone therapy resulted in suppression of plasma testosterone and androstenedione values, a significant increase in plasma SHBG and a marked fall in testosterone/SHBG. Following treatment with dexamethasone hyperandrogenaemia was corrected in 64% of hirsute patients, a decrease in the rate of hair growth or a resumption of a normal menstrual pattern occurred in 70% and concordant hormonal and clinical changes occurred in 79% of patients. These observations indicate that the testosterone/SHBG ratio is a sensitive index of hyperandrogenaemia, the correction of which is associated with clinical improvement.