Prevalence of Epilepsy among Cataract Patients

Purpose: To evaluate the prevalence of epilepsy among patients undergoing cataract surgery. Design: A retrospective observational case control study. Methods: We calculated the prevalence of epilepsy among all the patients older than 50 years who underwent cataract surgery (years 2000-2007, n = 12,984) in a district of the largest health maintenance organization in Israel (the Central District of Clalit Health Services) and among 25,968 age and gender matched controls. The database was screened for epilepsy by integrating the clinical and ancillary work-up as well as the drug regimen. The use of anti-epileptic drugs (AEDs) was evaluated among the cataract patients and the controls. The main outcome measure was the prevalence of epilepsy and antiepileptic medical treatment among patients undergoing cataract surgery versus controls. Results: No difference was found in demographics among the groups including age, gender, marriage status, socioeconomic class and living place between the study and control groups (except for patients origin). Epilepsy was found to be significantly more prevalent in patients undergoing cataract surgery. The odds ratio (OR) was 1.3 (95% confidence interval (CI): 1.1-1.6): 1.4 in men (95% CI: 1.1-1.9) and 1.2 in women (95% CI: 1.0-1.6). AEDs, particularly clonazepam (OR = 1.5, 95% CI: 1.1-2.1) and carbamazepine (OR = 1.4, 95% CI: 1.05-1.8), were also used more by cataract patients. Multivariate logistic regression analysis revealed a significant association between cataract surgery and epilepsy (OR 1.26, p < 0.001) as well as diabetes (OR 1.38, p < 0.001), arterial hypertension (OR 1.26, p < 0.001), smoking (OR 1.22, p < 0.001), hyperlipidemia (OR 1.12, p < 0.001), and Ashkenazi origin (OR 0.85, p < 0.001). Conclusions: Epilepsy is associated with the presence of cataract. Various hypotheses may explain this finding, including a cataractogenic role of AEDs.