35372 Skin type and efficacy of laser treatment for androgenic alopecia

Abstract

Introduction and methods: The use of low light laser therapy to treat androgenic alopecia is a promising modality to restore hair growth. However, the effect of skin color on the hair growth response to laser therapy has not been systematically explored in the literature. The objective of this study is to systematically assess, through a comprehensive literature search of the MEDLINE database, whether skin type data was collected in clinical trials and analyzed in each study and to determine if we can determine an effect. Results: 8/21 studies have defined inclusion criteria as Fitzpatrick skin type I-IV. 13/21 do not mention skin type or color in their study. No studies mentioned effects on darker skin types, Fitzpatrick skin type V-VI. Of the 8 studies, only 3 looked statistically at effect of Fitzpatrick skin on laser efficacy, with 2 showing no effect and 1 showing a significant positive effect with darker skin types having faster rate of hair growth. Conclusions: There are not enough data to conclude whether skin type effects laser induced hair growth in androgenic alopecia. The studies are severely lacking in sample size. One showed a potential effect. Importantly, there are no data on black or brown skin colors. Development of optimal laser irradiating parameters through the prediction of personalized absorbance based on skin color measurement could help control side effects of laser therapy and allow clinicians to calculate individualized settings that are less risky and more beneficial to diverse set of patients.