The prevalence and risk factors for age-related macular degeneration in rural-urban India, Sankara Nethralaya Rural-Urban Age-related Macular degeneration study, Report No. 1

Purpose To report the age-and gender-adjusted prevalence rates of early and late age-related maculopathy (ARM) and associated risk factors in rural and urban Indian population. Methods A population-based cross-sectional study was carried out in South India between 2009 and 2011. Of the 6617 subjects >= 60 years enumerated ones, 5495 (83.04%) participated in the eye examination. A detailed history including data on demographic, socioeconomic, and ocular history was obtained. Participants underwent detailed ophthalmic evaluation including 30 degrees 3-field photograph as per Age-Related Eye Disease Study protocol. The ARM was graded according to the International ARM Epidemiological Study Group. Results Age-and gender-adjusted prevalence of early ARM was 20.91% (20.86-20.94) in the rural population and 16.37% (16.32-16.42) in the urban population. Similarly, the prevalence of late ARM was 2.26% (2.24-2.29) and 2.32% (2.29-2.34) in the rural and urban population, respectively. In both rural and urban populations, risk factors that were related to both early and late ARM were age, per year increase (OR, range 1.00-1.08); middle socioeconomic status (OR, range 1.05-1.83); and smokeless tobacco (OR, range 1.11-2.21). Protective factor in both was the presence of diabetes mellitus in all ARM (OR, range 0.34-0.83). Risk factors, only in the rural arm, were female gender (OR, range 1.06-1.64), past smoker (OR, 1.14), and serum low-density lipoprotein cholesterol level (OR, 1.03). Conclusions The study reports smokessless tobacco as a risk factor for both early and late ARM and identified a higher prevalence of early ARM in the rural population compared with urban population.