Differential cataract blindness by sex in India: Evidence from two large national surveys

Aims: Women suffer disproportionately more from cataract blindness compared to males in low- and middle-income countries. Two large population-based surveys have been undertaken in India at an interval of 7 years and data from these surveys provided an opportunity to assess the trends in gender differentials in cataract blindness. Materials and Methods: Data were extracted from the surveys to discern sex differences in cataract blindness. Multivariate analysis was performed to adjust for confounders and their impact on gender differences in cataract blindness. Blindness was defined as presenting vision < 20/400 in the better eye, and a cataract blind person was defined as a blind person where the principal cause of loss of vision was cataract. Results: Prevalence of cataract blindness was higher in females compared to males in both surveys. The odds of cataract blindness for females did not change over time as observed in the surveys (1999-2001 and 2006-2007). Adjusted odds ratio from logistic regression analysis revealed that females continued to be at a higher risk of cataract blindness. Conclusions: Sex differences continued in India in relation to cataract blindness despite the gains made by the national program.