在银屑病患者中,记录的银屑病性关节炎患病率因研究设计不同而存在广泛差异。据观察,医院临床患者的患病率最高,反映更严重病例存在转诊偏倚。社区银屑病队列中的患病率要低得多,为 10% 以下。在最近一项采用新 CASPAR(银屑病性关节炎分类)标准的基于社区的研究中,银屑病性关节炎的 20 年累积发病率为 7.5%。[4]Wilson FC, Icen M, Crowson CS, et al. Incidence and clinical predictors of psoriatic arthritis in patients with psoriasis: a population-based study. Arthritis Rheum. 2009;61:233-239.http://www.ncbi.nlm.nih.gov/pubmed/19177544?tool=bestpractice.com41% 的关节炎病例已确诊合并银屑病。银屑病发作后,发展成关节炎的时间在 7 年左右[4]Wilson FC, Icen M, Crowson CS, et al. Incidence and clinical predictors of psoriatic arthritis in patients with psoriasis: a population-based study. Arthritis Rheum. 2009;61:233-239.http://www.ncbi.nlm.nih.gov/pubmed/19177544?tool=bestpractice.com
银屑病性关节炎的发病率可能在升高。在基于人群的一般性研究中,对性别和年龄修正后,每 100,000 人中发病率从 1970 年至 1979 年间的 3.6(95% 置信区间,2.9~5.2)上升到 1990 年至 2000 年间的 9.8(95% 置信空间,7.7~11.9)。[5]Wilson FC, Icen M, Crowson CS, et al. Time trends in epidemiology and characteristics of psoriatic arthritis over 3 decades: a population-based study. J Rheumatol. 2009;36:361-367.http://www.ncbi.nlm.nih.gov/pubmed/19208565?tool=bestpractice.com 该观察结果可反映银屑病的真实增长情况,也反映了较轻度类型银屑病性关节炎的更佳确证。[5]Wilson FC, Icen M, Crowson CS, et al. Time trends in epidemiology and characteristics of psoriatic arthritis over 3 decades: a population-based study. J Rheumatol. 2009;36:361-367.http://www.ncbi.nlm.nih.gov/pubmed/19208565?tool=bestpractice.com
虽然观察发现银屑病性关节炎在男性中更早发病,但是男性和女性的发病率相同。在女性中,银屑病性关节炎的发病率会在 60 岁时达到峰值,反映在女性中皮肤病的发病率在特定年龄上升。据推测,性激素影响性别差异。[4]Wilson FC, Icen M, Crowson CS, et al. Incidence and clinical predictors of psoriatic arthritis in patients with psoriasis: a population-based study. Arthritis Rheum. 2009;61:233-239.http://www.ncbi.nlm.nih.gov/pubmed/19177544?tool=bestpractice.com[5]Wilson FC, Icen M, Crowson CS, et al. Time trends in epidemiology and characteristics of psoriatic arthritis over 3 decades: a population-based study. J Rheumatol. 2009;36:361-367.http://www.ncbi.nlm.nih.gov/pubmed/19208565?tool=bestpractice.com