General Insight About Androgenetic Alopecia

Abstract

Background: Thinning of the hair usually begins between the ages of 12 and 40 years in both genders and approximately half the population expresses this trait to some degree before the age of 50. Ordinary, male pattern baldness as a rule begins with expanded fronto-temporal recession then mid-frontal retreat. A round territory on the vertex much of the time takes after as the thickness of hair diminishments over the lifted vertex hair. Androgenetic alopecia occurs in all populations but the prevelance is highest in Caucasians. Caucasian males are four-times more likely to develop AGA than males of African origin. Approximately 30% of Caucasian men are affected by 30 years of age, and at least 50% by 50 years of age .There is scant published information on frequency of balding in African men. Clinically, hairs from the frontal area to the vertex of the scalp become thin and short vellus hairs, resulting in a receding frontal hairline and hair loss in the vertex. In contrast to telogen effluvium, pattern hair loss is a characteristic of androgenetic alopecia. In men with androgenetic alopecia, the gradual replacement of long, pigmented, terminal hairs on the scalp by short, pale, vellus hairs normally occurs in a relatively precise pattern. Hamilton graded this progression from type 1, pre-pubertal scalp with terminal hair on the forehead and all over the scalp, through gradual regression of the frontal hairline and thinning on the vertex, to type VII where the bald areas became fully coalesced to leave hair only around the back and sides of the head. Norwood modified Hamilton’s classification, including variations for the middle grades. In a few occasions, some men create diffuse decreasing of the vertex hair with upkeep of the frontal hairline with an example which looks like the Ludwig pattern of hair loss seen within ladies.