The prevalence of melasma in the general population remains unknown. However, it has been reported for some specific populations: for example, in Latin-American women the prevalence was found to be 8.8%, and in pregnant women up to 50%, and it is considered to be the third most common pigmentary disorder in African-Americans.[1]Ball Arefiev KL, Hantash BM. Advances in the treatment of melasma: a review of the recent literature. Dermatol Surg. 2012 Jul;38(7 Pt 1):971-84.
http://www.ncbi.nlm.nih.gov/pubmed/22583339?tool=bestpractice.com
[5]Werlinger KD, Guevara IL, González CM, et al. Prevalence of self-diagnosed melasma among premenopausal Latino women in Dallas and Fort Worth, Tex. Arch Dermatol. 2007 Mar;143(3):424-5.
http://www.ncbi.nlm.nih.gov/pubmed/17372115?tool=bestpractice.com
[6]Rajaratnam R, Halpern J, Salim A, et al. Interventions for melasma. Cochrane Database Syst Rev. 2010;(7):CD003583.
http://www.ncbi.nlm.nih.gov/pubmed/20614435?tool=bestpractice.com
Overall, melasma is seen more commonly in people of Asian, Hispanic, and African-American descent.[6]Rajaratnam R, Halpern J, Salim A, et al. Interventions for melasma. Cochrane Database Syst Rev. 2010;(7):CD003583.
http://www.ncbi.nlm.nih.gov/pubmed/20614435?tool=bestpractice.com
The condition is seen most commonly in women (who account for approximately 90% of people with melasma), particularly those with darker skin (Fitzpatrick type III, IV, V, or VI).[7]Hexsel D, Lacerda DA, Cavalcante AS, et al. Epidemiology of melasma in Brazilian patients: a multicenter study. Int J Dermatol. 2014 Apr;53(4):440-4.
https://www.doi.org/10.1111/j.1365-4632.2012.05748.x
http://www.ncbi.nlm.nih.gov/pubmed/23967822?tool=bestpractice.com
[8]Achar A, Rathi SK. Melasma: a clinico-epidemiological study of 312 cases. Indian J Dermatol. 2011 Jul;56(4):380-2.
https://www.doi.org/10.4103/0019-5154.84722
http://www.ncbi.nlm.nih.gov/pubmed/21965843?tool=bestpractice.com
[9]Goh CL, Dlova CN. A retrospective study on the clinical presentation and treatment outcome of melasma in a tertiary dermatological referral centre in Singapore. Singapore Med J. 1999 Jul;40(7):455-8.
http://www.ncbi.nlm.nih.gov/pubmed/10560271?tool=bestpractice.com
Ultraviolet (UV) light intensifies this hyperpigmentation; melasma is therefore seen more frequently in people who live in areas of intense UV radiation, and it occurs most commonly in the summer.[2]Victor FC, Gelber J, Rao B. Melasma: a review. J Cutan Med Surg. 2004 Mar-Apr;8(2):97-102.
http://www.ncbi.nlm.nih.gov/pubmed/15685388?tool=bestpractice.com
The age of onset is between 20 and 29 years in 50% of patients.[10]Guinot C, Cheffai S, Latreille J, et al. Aggravating factors for melasma: a prospective study in 197 Tunisian patients. J Eur Acad Dermatol Venereol. 2010 Sep;24(9):1060-9.
http://www.ncbi.nlm.nih.gov/pubmed/20202051?tool=bestpractice.com