PLASMA-FREE ANDROGEN PATTERNS IN HIRSUTE WOMEN AND THEIR DIAGNOSTIC IMPLICATIONS

The 24-hour pattern of plasma total and free testosterone and other 17β-hydroxysteroids has been characterized in six women with moderately severe male-pattern hirsutism. Four distinct plasma androgen patterns were identified: (1) total and free plasma testosterone levels were elevated 80 per cent or more of the time, (2) the free plasma testosterone level was constantly elevated, whereas total testosterone was in the high-normal range, (3) plasma free androgens were undergoing marked phasic fluctuations around the upper limits of normal such that sampling blood for multiple androgens and/or at multiple intervals was necessary to disclose the hyperandrogenic state, and (4) plasma free androgens fluctuated within the normal range. The variation of the plasma androgens was suggestive of intermittent and independent episodes of adrenal and ovarian androgen production. Because of these fluctuations, a single plasma testosterone level was not necessarily representative of the average concentration over a 24-hour period. For example, the 95 per cent confidence limits are such that a single plasma testosterone level may fall within only 38 per cent of the 24-hour mean. The best short-term estimate of the average daily testosterone level is the mean of hourly determinations over a 3-hour period; the 95 per cent confidence limits of this figure are within 18 per cent of the 24-hour mean. Nevertheless, this 3-hour sampling protocol would not haue detected the subtle hyperandrogenic state present in two patients unless androgens other than free testosterone (e.g., free 17β-hydroxysteroids) were measured in the same plasma specimens. © 1979.