Abstract
Purpose: :
Smoking has been shown to be a risk factor for age-related macular degeneration and has been associated with a poor prognosis in inflammatory diseases. In uveitis, recent studies suggest that smoking is a risk factor for the development of complications in specific types of uveitis, but there is need for further studies on the association between smoking and all types of uveitis. The goal of this study was to determine whether or not past or current smoking was associated with the development of uveitis.
Methods: :
This was a retrospective, case-control, medical record review of all uveitis patients seen at the University of California San Francisco (USCF) Proctor Foundation eye clinic between 2004 and 2008. The control group included 270 randomly selected charts of non-uveitis patients seen in the UCSF comprehensive eye clinic within the same time period. Smoking history is routinely collected on new ophthalmology patients, and only records that had smoking history recorded (current smoker, past smoker, or never smoked) were included in the study. Information on race, age, and ocular diagnosis was also collected. The data was analyzed using Stata 9.2 software comparing dichotomous outcomes with a Fisher's exact test and risk factor analysis with a multivariate logistic regression analysis. Institutional review board approval was obtained prior to beginning this study.
Results: :
Of the 565 uveitis patients seen at UCSF between 2004 and 2008 with smoking data recorded, 205 (36.3%) reported a past or current history of smoking. Of the 270 randomly selected non-uveitis eye clinic patients seen at UCSF in the same time period, 61 (22.6%) reported a past or current history of smoking. This difference in proportions was statistically significant (P < 0.001). The mean age of uveitis patients was significantly younger (45 years) than the mean age of non-uveitis comprehensive eye clinic patients (54 years), P<0.001. A multivariate logistic regression analysis predicting uveitis as the outcome using smoking as a predictor while adjusting for age, sex and race, demonstrated that past or current smoking was associated with a 2.4-fold increased odds of having uveitis (95% CI 1.7 to 3.4, P < 0.001). Each 10-year increase in age was associated with a reduced risk of uveitis (OR 0.75, 95% CI 0.69 to 0.82, P < 0.001). There was a trend towards female sex being associated with a 1.3-fold increased odds of uveitis (95% CI 1.7 to 3.4, P = 0.06).
Keywords: autoimmune disease • uveitis-clinical/animal model • inflammation