Prevalence and clinical features of systemic diseases in Chinese patients with uveitis

Purpose Systemic diseases are frequently associated with uveitis but are often not recognised by clinicians. An estimate of the prevalence in a large-scale uveitis population is essential for understanding the epidemiological profile and may be helpful for clinical practice. Design A nationwide survey. Methods Data were obtained from a national database which included the registration of uveitis cases from 23 provinces, 5 autonomous regions and 4 municipalities across mainland China. The primary outcome was identification of a systemic disease associated with uveitis. Results From April 2008 through August 2018, 15 373 uveitis patients were included in the study. Males accounted for 52.9%, and the mean (SD) age of uveitis onset was 35.4 (15.9) years. After standardisation for age, the prevalence of systemic disease among patients with uveitis was 30.8% (95% CI, 30.1% to 31.6%). Vogt-Koyanagi-Harada disease (VKH; age-standardised prevalence, 12.7%; 95% CI, 12.1% to 13.2%), Behcet's disease (BD; 8.7%; 95% CI, 8.3% to 9.2%), ankylosing spondylitis (AS; 5.0%; 95% CI, 4.6% to 5.3%) and juvenile idiopathic arthritis (JIA; 1.2%; 95% CI, 1.0% to 1.3%) were the most common entities among 36 different forms of systemic diseases identified. The prevalence was significantly higher in males (37.0%; 95% CI, 36.0% to 38.1%) than in females (23.6%; 95% CI, 22.6% to 24.6%), and also higher in bilateral uveitis patients (41.2%; 95% CI, 40.2% to 42.2%) compared with unilateral cases (14.3%; 95% CI, 13.4% to 15.2%), and was highest in panuveitis (59.5%; 95% CI, 58.2% to 60.8%). Conclusion Approximately one third of uveitis patients in this nationwide survey have an associated systemic disease, whereby VKH, BD, AS and JIA are the most frequent entities seen in China.