Premature adrenarche

Adrenarche is the puberty of the adrenal gland. The descriptive term "pubar che" indicates the appearance of pubic hair, which may be accompanied by ax illary hair. This process is considered premature if it occurs before age 8 yr in girls and 9 yr in boys. The chief hormonal products of adrenarche ar e DHEA and DHEAS. The well-documented evolution of adrenarche in primates a nd men is incompatible with either a neutral or harmful role for DHEA and i mplies most likely a positive role for some aspects of young adult pubertal maturation and developmental maturation. Premature adrenarche has no adver se effects on the onset and progression of gonadarche and/or final height. Mechanisms for initiation of adrenal androgen secretion at adrenarche are s till not well understood. Maturational increases in 17-hydroxylase and 17,2 0-lyase are seen together with a lower activity of 3 beta -hydroxysteroid d ehydrogenase (3 beta -HSD). There is good evidence that the zona reticulari s is the source of adrenal androgens. Adrenarche and gonadarche are regulat ed differently. Although premature adrenarche has been thought to be a beni gn, normal variant of puberty, our findings indicate that, for certain girl s, premature adrenarche represents an early clinical feature of syndrome X (obesity, hypertension, dyslipidemia, insulin resistance). Perhaps the earl y identification of these patients will permit early therapy, such as lifes tyle changes, including dietary and activity level intervention. As insulin resistance is an underlying feature of premature adrenarche, it seems rati onal to assess the efficacy and safety of using insulin-sensitizing agents to treat these individuals. In the absence of controlled longitudinal studi es, the cross-sectional data available from our studies suggest that premat ure pubarche driven by premature adrenarche and hyperinsulinemia may preced e the development of ovarian hyperandrogenism, and this sequence may have a n early origin with low birth weight serving as a marker. Premature adrenar che may thus be a forerunner of syndrome X in some girls. (C) 2001, Editric e Kurtis.