Global prevalence of hidradenitis suppurativa and geographical variation—systematic review and meta-analysis

Background There is a significant variation in the reported prevalence of hidradenitis suppurativa (HS), ranging from 0.03–4%. We hypothesized that this significant variation may be due to different prevalence rates of HS according to geographical location as well as sex. Objective We aimed to perform a meta-analysis to determine pooled overall prevalence of HS, prevalence stratified according to geographical region and sex. Materials and methods A systematic review was performed by searching Ovid Medline, PubMed, Cochrane Library, DARE, and Embase, from inception to August 2018. A systematic review and meta-analysis was performed according to PRISMA guidelines. A meta-analysis of proportions was performed to determined pooled prevalence rates, with meta-regression based on geographic region. Prevalence in males versus females was also performed according to region. Results The overall pooled prevalence rate was 0.3% (0.2–0.6%) based on 118,760,093 HS cases available. Subgroup analysis demonstrated prevalence differences, with the highest being in Europe 0.8% (0.5–1.3%), compared to the USA 0.2% (0.1–0.4%), Asia-Pacific 0.2% (0.01–2.2%), and South America 0.2% (0.01–0.9%). Prevalence in males was lower compared to females in the USA (OR 0.403, 95% CI 0.37–0.439, P < 0.001) as well as in Europe (OR 0.635, 95% CI 0.397–1.015, P = 0.08) but not in the Asia-Pacific region (OR 0.936, 95% CI 0.319–2.751, P = 0.78). Conclusion Prevalence of HS varies significantly according to the geographical population. This variation is likely attributed to different ethnicity distributions amongst different continents. Level of evidence III