Epidemiology of melasma in Brazilian patients: a multicenter study

Melasma is an acquired, irregularly patterned, light to dark-brown hypermelanosis, with symmetric distribution mostly over the face. The aim of this study was to evaluate clinical characteristics and factors related to melasma in Brazilian patients.This was a cross-sectional, multicenter study performed in Brazil. Investigators examined and questioned 953 patients over 18 years of age on clinical characteristics and other factors related to their melasma.Melasma was more prevalent in women (97.5%) and in Fitzpatrick skin phototypes II (12.8%), III (36.3%), and IV (39.7%). Skin phototypes II and III and family history of melasma had early onset of the disorder when compared with skin phototypes IV, V, and VI (P<0.0001). Similar results were also observed when these same groups were compared with the absence of family history (P<0.0001). Extra-facial melasma was more frequent in postmenopausal women compared with those who were not experiencing menopause (14.2% vs. 3.5%, P<0.0001).Data suggested that the age of melasma onset are related to skin phototypes and family history. Additionally, extra-facial melasma was more common in menopausal women. This is the first study on the epidemiology of melasma in Brazil involving a large sample of the population. These data can be a source of new relevant research on the cause and development of melasma.