The effectiveness of finasteride and dutasteride used for 3 years in women with androgenetic alopecia

Abstract

Background: The effectiveness of finasteride and dutasteride in women with androgenetic alopecia has been the subject of debate. Aim: To evaluate the effectiveness of finasteride and dutasteride on hair loss in women with androgenetic alopecia over a period of 3 years. Methods: From a database containing systematically retrieved data on 3500 women treated for androgenetic alopecia between 2002 and 2012 with finasteride 1.25 mg or dutasteride 0.15 mg, a random sample stratified for age and type of medication was taken to yield 30 women in two age categories: below and above 50 years, and for both medications. Hair thickness of the three thinnest hairs was measured from standardized microscopic images at three sites of the scalp at the start of the treatment and after 3 years of continuous medication intake. The macroscopic images were evaluated independently by three European dermatologists/hair experts. The diagnostic task was to identify the image displaying superior density of the hair. Results: Both age categories showed a statistically significant increase in hair thickness from baseline over the 3‑year period for finasteride and dutasteride (signed rank test, P = 0.02). Hair thickness increase was observed in 49 (81.7%) women in the finasteride group and in 50 (83.3%) women in the dutasteride group. On average, the number of post-treatment images rated as displaying superior density was 124 (68.9%) in the finasteride group, and 118 (65.6%) in the dutasteride group. Dutasteride performed statistically significantly better than finasteride in the age category below 50 years at the central and vertex sites of the scalp. Conclusions: Finasteride 1.25 mg and dutasteride 0.15 mg given daily for 3 years effectively increased hair thickness and arrested further deterioration in women with androgenetic alopecia.