Regional variation in the incidence of pseudo-exfoliation in the Andhra Pradesh Eye Disease Study (APEDS)

Background To report the 15-year incidence rate of pseudo-exfoliation (PXF), PXF glaucoma and regional variation among rural participants in the Andhra Pradesh Eye Disease Study (APEDS) III. Methods This population-based longitudinal study was carried out at three rural study sites. Individuals of all ages who participated at baseline with a mean 15-year follow-up visit were included. Detailed Comprehensive ophthalmic examination was performed on all participants. The main outcome measure was development of PXF during the follow-up period in participants who were phakic in one or both eyes without PXF at baseline. Results Among 5395 participants, 5108 (94.6%) met the inclusion criteria. There were 93 (1.82%; 95% confidence interval (CI), 1.47-2.22) cases of incident PXF. Their median baseline age (1st, 3rd quartiles) was 51 (44, 59) years and the male: female ratio was 1.3:1. There was no case of incident PXF in participants aged <30 years at baseline. The incidence rate per 100 person years (95% CI) among all ages and those aged >= 30 years at baseline was 1.73 (1.64-1.82) and 3.73 (3.53-3.93), respectively. PXF material was located on iris as well as anterior surface of lens and it was often bilateral. Participants living in two study sites and increasing age were associated with the incidence of PXF. The 15-year incidence of PXF glaucoma (95% CI) in participants >= 30 years of age at baseline was 0.33% (0.14-0.66). Conclusion There is significant regional variation in incidence of PXF in south India which warrants further investigation.