Is androgenic alopecia a result of endocrine effects on the vasculature?

Androgenic alopecia is a condition of concern for many patients. Though much has been learned about this condition, the exact pathophysiological mechanism is yet to be established. Currently most study concerning androgenic alopecia has focused on the effects of androgens on the pilosebaceous unit itself. An area of study that has received considerably less attention is that of androgens inducing baldness by indirect effects, that is, effects on tissues other than the pilosebaceous unit. In this paper, the author offers a novel hypothesis in which androgenic hair loss is mediated via the effects of androgens on the vasculature supplying the scalp. In this new hypothesis androgens effect anatomical changes in the vasculature of susceptible individuals, resulting in an environment in which hair growth is hindered and eventually ceases. The author discusses past studies demonstrating the effects of androgens on vessels and how these effects may relate to anatomical changes in the vasculature leading to hair loss. Also included is a discussion on future experimentation to test this new hypothesis.