MALE PATERN BALDNESS

BY PROF BARRY STEVENS

As medical/scientific research continues, current opinion as expressed herein may change. Man is almost totally hair covered. Lanugo hair covers the foetus until the seventh month whereupon it is lost. Postnatal hair is usually Vellus and Terminal. Vellus hair is capable of change at puberty.

Terminal hair is the subject of this paper. Throughout the ages of man, hair loss has been little understood. Research is progressively adding to our understanding of this complex vexatious problem which affects approx. 65% of caucasoid males and approx. 45% of caucasoid women by the age of 55 years.

Currently we are evidencing treatments with lasers, Minoxidil, and too many ‘snake oil cures’ to list here. With the exception of hair follicle redistribution surgery (which has its limitations) no reliable treatments have been marketed.

Androgenetic and Androgenic Alopecias share a common factor – each is androgen related. The former is genetically inspired, the latter is acquired. Some recent reliable research into AGA comes from EHRS, I incorporate some of their findings in this paper.

Androgenetic alopecia (AGA) is associated with the androgen dihydrotestosterone (5-alpha -DHT) which is the principle pathogen affecting androgen-sensitive hair follicles. It is apparent that individuals possessing enzyme type 2 steroid 5 alpha-reductase tend to develop AGA. Individuals who lack it tend not to develop AGA.

AGA can therefore be categorised as a DHT (dihydrotestosterone) mediated process characterised by the inexorable miniaturization of androgen sensitive follicles. AGA treatment aims therefore to stop or reverse the process of follicle miniaturisation.

This may in theory be accomplished by preventing the formation of DHT via the drug Finasteride (Propecia) or by modulating DHT-binding to the androgen receptor with drugs e.g. Cyproterone Acetate. However it has been demonstrated that other enzymes e.g. Aromatase and 3 alpha -hydoxysteroid-dehydrogenase may also be involved in the local metabolism of DHT.

Aromatase which has been found in epithelial follicular tissue should diminish the quantity of intra-follicular testosterone available for conversion into DHT.

3 alpha -hydoxysteroid-dehydrogenase found to be present in the dermal papilla actually accelerates DHT dependent hair follicle activity (scalp hair loss and secondary sexual body hair increase).

Is it possible therefore that AGA may respond to increased levels of Aromatase and decreased levels of 3 alpha-hydoxysteroid-dehydrogenase. Further research is required.

Treatments

Medical treatments currently available:

We accept that testosterone conversion to DHT by steroid 5 alphareductase plays a crucial role in AGA and Prostatomegaly. Research has shown that specific substances e.g. synthetic finasteride and dutasteride inhibit the conversion and may promote hair growth.

We are conscious that 5 alpha-reductase inhibiting drugs were found to potentially cause deformities in the male foetus of breeding mice so may be unsuitable as a treatment for AGA in males who may be fathering children.

Whereas some current opinion suggests that abstention from the drug for a period of approximately three months will negate any risk, opinion amongst some prospective patients is one of concern. Can we also ignore the possibility of long-term side effects – as yet unknown!

Surgical

Hair follicles cease to regenerate hairs due to androgenic (endocrine changes) or androgenetic (inherited androgen related factors). Rarely is this associated with hat wearing, circulatory or vitamin deficiency. Men and women are affected.

Female pattern loss may commence as a single coin-sized thinning patch in a central position just behind the fringe area. This thinning may extend to inculcate much of the scalp. One in five women will probably experience some degree of hair thinning associated with illness, ageing, hormonal changes after menopause or heredity. Wigs may be an answer. Topical prescription drugs may assist, but rarely is lost hair replaced-naturally.

Hair restoration surgery offers one possible solution. The best candidates for this procedure are sufferers of scalp damage and androgenic or androgenetic alopecia. The procedure involves the redistribution of an individual’s hair bearing follicles from safe ‘donor’ sites at the occiput to the balding regions. A skilled specialist surgeon can produce remarkable results dependent upon the availability of adequate numbers of donor follicles.

Techniques used: e.g. scalp reduction, micro-grafts (containing a single hair) and mini-grafts (containing two or three hairs), flaps and tissueexpansion. More than one technique may be employed during a procedure. As suitability to each technique depends on individual circumstances, one to one advice is essential

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