Vogt-Koyanagi-Harada disease frequency around the globe: a systematic review and meta-analysis

Vogt-Koyanagi-Harada (VKH) disease has been historically associated with specific ethnic groups, suggesting an underlying susceptibility. Prior to this study, no meta-analysis had synthesized the global epidemiology of VKH, and therefore, information on its geographic distribution remained incomplete. The present study aims to determine the global distribution of VKH disease diagnosis in individuals presenting with uveitis.

A systematic review and meta-analysis of quantitative studies published between 2001 and 2025 in PubMed, SciELO, and LILACS was conducted following PRISMA-P guidelines. Case reports were excluded. Risk of bias was assessed using the Murad assessment tool for case series. A random-effects model was used to pool frequency estimates with 95% confidence intervals and prediction intervals.

Of 7153 articles identified, 258 studies were analyzed, spanning six continents and 44 countries. The estimated frequency of VKH among uveitis cases was 5.11% (CI:4.31-5.90%; PI: 0.00-15.18%) overall, with predominance of females. When subgrouped into pediatric and adult populations, the estimated frequency was 2.43% (CI:1.83-3.02%; PI: 0.00-6.38%) and 6.15% (CI:4.06-8.24%; PI: 0.00-19.77%), respectively. Frequencies varied across regions, with higher rates reported in Southeast Asia, East Asia, and Africa, and lower rates in North America, Europe, and Oceania. Regarding the quality evaluation, most studies were considered as medium-high quality (162/169, 96%).

This systematic review and meta-analysis support the existence of geographical differences in VKH disease expression and the need for additional epidemiological research, particularly in underrepresented regions. These findings should be interpreted in the context of methodological heterogeneity and potential publication and geographic bias.