Risks of relapse in patients with acute anterior uveitis.

Aim: To quantify the rate of recurrence of acute anterior uveitis (AAU), and evaluate the influence of associated risk factors.

Methods: We retrospectively reviewed the case notes of 185 patients with acute anterior uveitis, from their time of presentation to August 2001. The time to the first three recurrences of AAU from the onset of the disease was recorded, as well as the site of recurrence. Information regarding risk factors (for example (HLA-B27) status, spondyloarthropathy (SpA), family history of AAU/SpA and history of non-specific joint pain) were also collected.

Results: Patients were followed up until their third relapse, or up to the censoring date (August 2001) if less than three relapses had occurred. The median length of follow-up was 35 months. One hundred and twenty-two patients (66%) developed at least one relapse and 67 (36%) had three or more relapses. Kaplan-Meier estimate of median interval between disease onset and the first relapse was 24 months 95% CI (16 to 34) and between the first and second relapse was 14 months 95% CI (9 to 22), and was 15 months 95% CI (10 to 25) months between the second and third relapse. Using Cox regression only the number of previous relapses was significantly associated with the risk of AAU recurrence. There was no significant association between other reported risk factors and the risk of relapse, and neither did any risk factor significantly modify the association between previous relapses and AAU recurrence (p>0.066 for all interactions). There was a borderline significant difference in survival according to the laterality pattern of recurrences (ipsilateral, alternate, or bilateral) with a slightly greater than expected number of events in those with bilateral recurrence (p = 0.048).

Conclusion: Patients with previous relapse(s) of AAU have a greater risk of AAU recurrence compared to those at disease onset but the risk of recurrence appears not to increase in a dose-response manner with increasing number of previous relapses. Demographic and extraocular features do not appear to influence the rate, or risk of recurrence of AAU.