Cigarette smoking as a risk factor for uveitis

Purpose: To determine the association between tobacco smoking history and uveitis.

Design: Retrospective, case-control study.

Participants: A total of 564 patients with ocular inflammation seen in the Proctor Foundation uveitis clinic between 2002 and 2009, and 564 randomly selected patients seen in the comprehensive eye clinic within the same time period.

Methods: A retrospective medical record review of all cases and controls.

Main outcome measures: A logistic regression analysis was conducted with ocular inflammation as the main outcome variable and smoking as the main predictor variable, while adjusting for age, gender, race, and median income.

Results: The odds of a smoker having ocular inflammation were 2.2-fold that of a patient who had never smoked (95% confidence interval [CI], 1.7-3.0; P<0.001). All anatomic subtypes of uveitis were associated with a positive smoking history, with odds ratios (ORs) of 1.7 (95% CI, 1.2-2.4; P = 0.002) for anterior uveitis, 2.7 (95% CI, 1.4-5.6; P = 0.005) for intermediate uveitis, 3.2 (95% CI, 1.3-7.9; P = 0.014) for posterior uveitis, and 3.9 (95% CI, 2.4-6.1; P<0.001) for panuveitis. In patients with panuveitis and cystoid macular edema (CME), the OR was 8.0 (95% CI, 3.3-19.5; P<0.001) compared with 3.1 (95% CI, 1.8-5.2; P<0.001) for patients without CME. Patients with intermediate uveitis and CME also had a higher OR (OR 8.4; 95% CI, 2.5-28.8; P = 0.001) compared with patients without CME (OR 1.5; 95% CI, 0.6-3.8; P = 0.342). Patients with a smoking history were at greater odds of having infectious uveitis (OR 4.5; 95% CI, 2.3-9.0; P<0.001) than noninfectious uveitis (OR 2.1; 95% CI, 1.6-2.8; P<0.001), although both were associated with smoking.

Conclusions: A history of smoking is significantly associated with all anatomic subtypes of uveitis and infectious uveitis. The association was greater in patients with intermediate uveitis and panuveitis with CME compared with those without CME. In view of the known risks of smoking, these findings, if replicated, would give an additional reason to recommend smoking cessation in patients with uveitis.