尽管 PLE 是最常见的光照性皮肤病,但缺乏患病率和发病率的数据,主要是由于仅有一小部分受影响的人群在出现症状时咨询医生。在美国,一般人群中的患病率为 10%,[15]Morison WL, Stern RS. Polymorphous light eruption: a common reaction uncommonly recognized. Acta Derm Venereol. 1982;62:237-240.http://www.ncbi.nlm.nih.gov/pubmed/6179365?tool=bestpractice.com 而 26% 的接受光敏性疾病评估的患者被诊断为 PLE。 [16]Fotiades J, Soter NA, Lim HW. Results of evaluation of 203 patients for photosensitivity in a 7.3-year period. J Am Acad Dermatol. 1995;33:597-602.http://www.ncbi.nlm.nih.gov/pubmed/7673491?tool=bestpractice.com但是,在最近一项对 2220 名皮肤病患者进行的回顾性研究中,41.1% 的白人患者被诊断为 PLE。[17]Kerr HA, Lim HW. Photodermatoses in African Americans: a retrospective analysis of 135 patients over a 7-year period. J Am Acad Dermatol. 2007;57:638-643.http://www.ncbi.nlm.nih.gov/pubmed/17630044?tool=bestpractice.com女性似乎更常受到影响(女性与男性的比率为 2:1),但尚不清楚这是否是由于报告偏差或遗传易感性。[1]Holzle E, Plewig G, von Kries R, et al. Polymorphous light eruption. J Invest Dermatol. 1987;88(3 Suppl):32s-38s.http://www.ncbi.nlm.nih.gov/pubmed/3819473?tool=bestpractice.com[9]Berg M. Epidemiological studies of the influence of sunlight on the skin. Photodermatology. 1989;6:80-84.http://www.ncbi.nlm.nih.gov/pubmed/2748434?tool=bestpractice.com[18]Aubin F. Why is polymorphous light eruption so common in young women? Arch Dermatol Res. 2004;296:240-241.http://www.ncbi.nlm.nih.gov/pubmed/15349790?tool=bestpractice.com[19]Millard TP, Bataille V, Snieder H, et al. The heritability of polymorphic light eruption. J Invest Dermatol. 2000;115:467-470.http://www.jidonline.org/article/S0022-202X%2815%2940996-0/fulltexthttp://www.ncbi.nlm.nih.gov/pubmed/10951285?tool=bestpractice.com[20]McGregor JM, Grabczynska S, Vaughan R, et al. Genetic modeling of abnormal photosensitivity in families with polymorphic light eruption and actinic prurigo. J Invest Dermatol. 2000;115:471-476.http://www.jidonline.org/article/S0022-202X%2815%2940997-2/fulltexthttp://www.ncbi.nlm.nih.gov/pubmed/10951286?tool=bestpractice.com通常情况下,青少年或青年更常受影响;但是所有年龄组均可受到影响,因为 PLE 往往定期复发,并持续多年。[1]Holzle E, Plewig G, von Kries R, et al. Polymorphous light eruption. J Invest Dermatol. 1987;88(3 Suppl):32s-38s.http://www.ncbi.nlm.nih.gov/pubmed/3819473?tool=bestpractice.com[8]Guarrera M, Micalizzi C, Rebora A. Heterogeneity of polymorphous light eruption: a study of 105 patients. Arch Dermatol. 1993;129:1060-1061.http://www.ncbi.nlm.nih.gov/pubmed/8352615?tool=bestpractice.com
虽然该病似乎更常见于有白皙皮肤类型的人群,但一些研究也报告在有较深色皮肤类型的人群(包括非裔美国人)中有高发病率。[16]Fotiades J, Soter NA, Lim HW. Results of evaluation of 203 patients for photosensitivity in a 7.3-year period. J Am Acad Dermatol. 1995;33:597-602.http://www.ncbi.nlm.nih.gov/pubmed/7673491?tool=bestpractice.com[17]Kerr HA, Lim HW. Photodermatoses in African Americans: a retrospective analysis of 135 patients over a 7-year period. J Am Acad Dermatol. 2007;57:638-643.http://www.ncbi.nlm.nih.gov/pubmed/17630044?tool=bestpractice.com[21]Nakamura M, Henderson M, Jacobsen G, et al. Comparison of photodermatoses in African-Americans and Caucasians: a follow-up study. Photodermatol Photoimmunol Photomed. 2014;30:231-236.http://www.ncbi.nlm.nih.gov/pubmed/24118606?tool=bestpractice.com 北欧比南欧的发病率更高,可能是由于浅色皮肤类型、高光敏性和潜在遗传易感性。[19]Millard TP, Bataille V, Snieder H, et al. The heritability of polymorphic light eruption. J Invest Dermatol. 2000;115:467-470.http://www.jidonline.org/article/S0022-202X%2815%2940996-0/fulltexthttp://www.ncbi.nlm.nih.gov/pubmed/10951285?tool=bestpractice.com[20]McGregor JM, Grabczynska S, Vaughan R, et al. Genetic modeling of abnormal photosensitivity in families with polymorphic light eruption and actinic prurigo. J Invest Dermatol. 2000;115:471-476.http://www.jidonline.org/article/S0022-202X%2815%2940997-2/fulltexthttp://www.ncbi.nlm.nih.gov/pubmed/10951286?tool=bestpractice.com[22]Ros AM, Wennersten G. Current aspects of polymorphous light eruptions in Sweden. Photodermatology. 1986;3:298-302.http://www.ncbi.nlm.nih.gov/pubmed/3547354?tool=bestpractice.com在诸如澳大利亚之类的国家中,白种人群 PLE 的发病率也较高,与在北欧的发病率近似。[23]Pao C, Norris PG, Corbett M, et al. Polymorphic light eruption: prevalence in Australia and England. Br J Dermatol. 1994;130:62-64.http://www.ncbi.nlm.nih.gov/pubmed/8305319?tool=bestpractice.com