More Insight Into Link Between Uveitis, Cataract

Almost half of patients with treated uveitis underwent cataract surgery during a median follow-up of 7 years, according to a secondary analysis of a randomized trial.

The analysis of 125 eyes in 74 patients showed a 43% cumulative incidence of cataract surgery with no evidence of a plateau. A year after surgery, best corrected visual acuity (BCVA) had improved by 4.8 ETDRS (Early Treatment of Diabetic Retinopathy Study) lines to a median 20/25 vision.

Risk factors for cataract surgery included older age, use of topical corticosteroids, and use of glaucoma medication, along with a possible trend for history of anterior chamber inflammation, reported Douglas Jabs, MD, of the Johns Hopkins Bloomberg School of Public Health in Baltimore, and co-authors in the American Journal of Ophthalmology.

“Our data suggest a substantial and ongoing incidence of cataract surgery among patients with intermediate, posterior, and panuveitides treated with systemic therapy,” the authors concluded in a pre-proof of the article. “The results also suggest favorable visual acuity results after cataract surgery among these patients … The primary limitation on visual acuity results after cataract surgery appears to be chorioretinal disease or damage.”

The results added to a substantial evidence base regarding the relationship between uveitis and cataract. Cataracts are a recognized complication of uveitis and appear to be more common in patients with anterior uveitides. Data from retrospective studies have suggested a cataract surgery incidence in patients with uveitis of 6-9% per person-year and 5-9% per eye-year, the authors noted.

The risks posed by uveitides can extend to cataract surgical procedures, as well. A recent study from New Zealand examined the frequency of additional intraoperative procedures, intraoperative and postoperative complications, and postoperative visual outcomes and complications in 471 eyes of 371 patients who underwent cataract surgery necessitated by uveitis.

The most common additional procedures in that study were posterior synechiae peel (32.3%) and vision blue (18.1%). Intraoperative complications occurred infrequently (6.8% of eyes), and the most common postoperative complication was uveitis flare (56.5%). Postoperative cystoid macular edema occurred in about 10% of eyes. By 12 months, 80% of eyes had 20/50 vision or better.

The authors concluded, “Careful monitoring is important as complications can be unpredictable and occur later than expected.”

Jabs and coauthors examined the incidence of cataract surgery and risk factors for surgery in patients with uveitis treated with systemic corticosteroids and immunosuppression in the MUST trial and its follow-up study. The primary outcomes of the analysis were incidence of cataract surgery and visual acuity after surgery.

Of the 125 eyes included in the analysis, 34% had uveitis with anterior chamber inflammation, anterior/intermediate uveitis (12%), or panuveitis (22%). Additionally, 39% of eyes were being treated with topical corticosteroids, and 9% of eyes were being treated with glaucoma medications to lower intraocular pressure. One-fourth of the eyes had macular edema at baseline, and 60% had some degree of cataract formation. The median baseline BCVA was 20/32.

The 43% cumulative incidence of cataract surgery at 7 years was consistent with previous estimates from retrospective studies. Although the incidence curve did not plateau, the highest incidence appeared to be in the first 2 years after randomization.

Multivariate analysis of time-varying factors identified three statistically significant risk factors for cataract surgery:

• Age over 50: HR 2.86, 95% CI 1.52-5.42 (P=0.001)
• Use of topical corticosteroids: HR 3.13, 95% CI 1.42-6.94 (P=0.005)
• Use of glaucoma medication: HR 2.75, 95% CI 1.38-5.47 (P=0.004)

Prior anterior chamber inflammation conferred a numerically increased risk of cataract surgery (HR 1.90, 95% CI 0.95-3.84, P=0.07), as did treatment with prednisone doses greater than 7.5 mg/day (HR 1.36, 95% CI 0.69-2.71, P=0.37).

Postoperative visual acuity remained relatively stable for most eyes and did not change significantly over time, the authors stated. Improvement in visual acuity was greater for eyes that had worse preoperative vision.