Six-year incidence and baseline risk factors for pseudoexfoliation in a south Indian population: The chennai eye disease incidence study

Objective To estimate the 6-year incidence of pseudoexfoliation and its risk factors in a South Indian population. Design Longitudinal population-based study. Participants Subjects 40 years of age or older without pseudoexfoliation at baseline. Methods Participants were examined at baseline and after a 6-year interval. The presence of pseudoexfoliation was looked for after pupillary dilation in either or both eyes at 1 or more locations. Glaucoma was defined using the International Society of Geographical and Epidemiological Ophthalmology Classification. Logistic regression was performed to identify the baseline risk factors that could predict the incident pseudoexfoliation. Main Outcome Measures Six-year incidence, associated risk factors, and rural-versus-urban differences. Results From the study cohort of 4228 subjects, 87 subjects (male-to-female ratio, 48:39; rural-to-urban ratio, 69:18) demonstrated incident pseudoexfoliation (2.03%; 95% confidence interval [CI], 1.6-2.5; rural: -2.86%; 95% CI, 1.6-2.5; urban: 0.96%; 95% CI, 0.5-1.4). Pseudoexfoliation was associated with glaucoma in 1 subject (1.1%), with primary angle-closure suspicion in 10 subjects (11.5%), and with ocular hypertension in 2 subjects (2.2%). Significant predictive baseline risk factors were older age (P < 0.001), rural residence (P < 0.001), illiteracy (P = 0.02), pseudophakia (P = 0.04), and nuclear cataract (P = 0.05). With reference to the 40-to-49-year age group, the risk of incidence increased from 4.7 (95% CI, 2.4-9.4) for the 50-to-59-year age group to 12.9 (95% CI, 6.1-27.2) for 70 years of age and older group. Conclusions In 6 years, pseudoexfoliation developed in 2.03% of the population. Rural and urban incidence was significantly different.