Place-based exposure and cataract risk in the Beaver Dam cohort.

According to the Centers for Disease Control and Prevention, with an aging U.S. population an estimated 30 million people will be diagnosed with cataract by 2020. Several modifiable risk factors have been identified for nuclear cataract, cortical cataract, and posterior subcapsular cataract (PSC), including smoking, diabetes, and steroid medications. In the study described here, the authors evaluated residential location as a potential proxy of risk factors for cataracts in the Beaver Dam Eye Study cohort established in 1987. Cataract risk was calculated using general estimating equation modeling to account for correlation between eyes. Fifteen-year cumulative incidence rates were calculated for each type of cataract by eye. Of the 4926 study participants, 3253 seen at the baseline examination were included in the analyses. Compared to urban residents, the odds ratio (95% confidence interval) for rural participants' risk of cortical, nuclear, and PSC was 0.92 (0.73, 1.16), 0.85 (0.69, 1.06), and 0.71 (0.48, 1.05), respectively, adjusting for age, sex, educational status, and smoking status. The lowest cumulative incidences were for those living in rural areas, compared to edge or urban areas for all three types of cataracts.