Androgenetic alopecia affects between 50 and 80% of Caucasian men. A rule of thumb is for men in their thirties, 30% have androgenetic alopecia. For men in their forties, 40% have alopecia and so on until 80% of men are affected when 80 or more years old. Different ethnic backgrounds have different susceptibility levels towards the development of androgenetic alopecia. The Chinese male population has a similar progressive increase in those affected with advance in age but in total baldness is much less common compared to Caucasian males. The numbers of Chinese males affected by androgenetic alopecia is approximately half that of Caucasian males. American Indians and African Americans also have a lower incidence of androgenetic alopecia compared to Caucasians. These frequency differences between races suggests genetic predisposition is important in pattern baldness susceptibility.
