Polycystic ovary syndrome and the androgen-insulin connection.

The association of hyperandrogenism, insulin resistance, and polycystic ovarian disease is well established. The accompanying hyperinsulinemia results in acanthosis nigricans, an epiphenomenon of this syndrome. The knowledge that states of insulin resistance of diverse causes are associated with ovarian hyperandrogenism makes the argument for insulin-driven ovarian androgen secretion compelling. However, equally compelling evidence suggests that hyperandrogenism may contribute to insulin resistance and hyperinsulinemia. The irreconcilable differences between these two hypotheses have resulted in an array of contradictory studies. In this article a unified concept of polycystic ovary syndrome and its androgen-insulin connection is proposed. The hypothesis incorporates the role of hyperinsulinemia in the androgen excess observed (and vice versa); the key to this connection is the androgen-dependent change in regional body fat distribution and its metabolic consequence. The pathophysiologic features of polycystic ovary syndrome, which has important clinical sequelae, deserve further consideration.