The endocrinology of baldness.

Abstract

The endocrinology of baldness Male pattern baldness, scientifically known as androgenetic alopecia (AGA), is a very common condition, universally prevalent, which progresses with aging. The loss of scalp hair of any degree both in men and women is a cause of considerable psychological distress associated with a loss of self-esteem and feelings of diminished self-image, resulting in introversion and depression. Particularly among men, the very manifest obviousness of baldness is often a source of major psychological anguish. Two clinical features of male baldness have been recognized: a predisposition to scalp hair loss inherited from the father or grandfather(s) and a negative connection of scalp hair loss with the testes. Eunuchs and pre-pubertally castrated men who fail to develop body hair have normal scalp hair which shows no sign of loss with age. However, castrates receiving lifelong replacement therapy with testosterone show scalp hair loss and various degrees of baldness. The complete restoration of body hair in eunuchs and castrates by the administration of testosterone established the notion that androgens are responsible for hair growth, but at the same time it revealed the hair loss effect of testosterone on scalp hair. 1 The paradox of a diametrically different action of a hormone on its receptors aroused much interest and initiated research into the dual effect of testosterone and into the investigation of this biological aberrance that has created an unwanted phenotypic manifestation which, because of its great prevalence, the psychological impact and the difficulties and cost of treatment, is an important medicosocial problem. This review is a discussion on the endocrine connections at the hormonal, molecular and genetic levels with male and female scalp hair loss and on the psychological effects. Also discussed is the theory that baldness may be an early prognostic marker of prostate cancer and cardiovascular disease. The psychological effecTs of baldness Head hair is an essential complimentary feature to the face in the composition of an individual’s physiognomy and, by virtue of its natural qualities and its capacity to be modeled artistically, contributes significantly to an individual’s self-perceived image as well as to the response of others. It is therefore only natural that hair loss to any degree will have a negative psychological impact on the quality of a person’s life. Several studies have documented the psychological distress caused by baldness and investigated its parameters.