Comprehensive Update on Multiple Sclerosis-Associated Uveitis and New Epidemiological Insights from the United Kingdom.

Multiple sclerosis (MS)-associated uveitis is characterised most frequently by bilateral intermediate uveitis with peripheral vascular leakage or panuveitis. The interesting association between these autoimmune diseases, which develop in two immune-privileged sites, places some undifferentiated uveitis patients at heightened risk of demyelination and clinical MS precipitation from the use of licensed anti-tumour necrosis factor α (TNFα) biologic therapy. However, their association may also open novel treatment avenues, considering the rapidly expanding arsenal of highly effective MS disease-modifying therapies. Here, we offer new data on MS-uveitis from the first national population-representative matched case-control and cohort study, using IQVIA medical research data (IMRD-UK), a primary care database of 11 million people. Amongst 25 thousand uveitis cases, patients with (any) uveitis are nearly three times more likely than matched controls to develop MS by 15 years follow-up (adjusted Hazard 2.7 (95% CI 2.1-3.6, p < 0.001)), but the proportion of MS-uveitis is low overall (0.72%, 180/24,895 uveitis cases). What tools might enhance MS risk stratification in uveitis patients in the future? In this comprehensive narrative review, we summarise primary observational data informing our epidemiological understanding of the association between MS and uveitis, and its variable clinical presentations, to highlight the state of play, and the important questions that remain in MS-uveitis.