Gender and laterality affect recurrences of acute anterior uveitis

Aim: Acute anterior uveitis (AAU) associated with HLA-B27 or axial spondyloarthritis (axial SpA) is primarily unilateral and recurrent. We tested the hypotheses that disease laterality and gender affected recurrences of AAU. Methods: We studied 207 AAU subjects who were either HLA-B27 positive or had a verified history of axial SpA with documentation of the first uveitis episode. We recorded gender, laterality, duration, and time between episodes. Results: Of 207 subjects, 126 (60.9%) had axial spondyloarthritis. Of the 179 with known HLA-B27 status, 174 (97.2%) were HLA-B27 positive. The initial episode of AAU occurred slightly more often in the right eye, 109 (52.6%), than in the left, 91 (44.0%) or bilaterally, 7 (3.4%), but the difference between right and left was not significant (p=0.23). Interestingly, 69.4% of subsequent episodes occurred in the same eye affected previously (95% CI 59.3%, 78.3%, p=0.0001). In subjects with recurrent AAU, the probability of being disease-free for one year was 38.9% (95% CI 29.1%, 52.0%) using Kaplan-Meier estimates. Univariate analyses showed that male gender (p=0.03) and AAU which recurred in the same eye (p=0.04) was associated with a shorter time interval between episodes. Multivariate analysis by the Cox proportional hazards model showed similar results. Conclusions: The initial episode of unilateral AAU associated with HLA-B27 or axial SpA randomly affects either eye. Subsequent episodes occur more often in the same eye previously affected. Male gender and history of unilateral AAU in the same eye are associated with a shortened time interval between relapses.