The association of cooking fuels with cataract among adults aged 50 years and older in low- and middle-income countries: Results from the WHO Study on global AGEing and adult health (SAGE)

Reducing household air pollution and protecting eye health are essential to achieve the Sustainable Development Goals (SDGs). There is contradictory evidence about the association between cooking fuels and cataract among adults aged 50 years and older. WHO Study on global AGEing and adult health (SAGE) was conducted in six low- and middle-income countries (LMICs). We used propensity-score method (inverse probability of weighting) and logistic regression to examine the association between cooking fuels and self-reported cataract. Odds ratio (OR) estimates and 95% confidence intervals (CIs) were calculated. Overall, use of unclean fuels was associated with an adjusted OR of cataract of 1.42 (95%CIs, 1.29-1.56). In subgroup analysis, unclean cooking fuels increased 1.71 (95%CI, 1.46-2.01) and 1.53 (95%CI, 1.30-1.79) times the risk of cataract in India and China, respectively, whereas no association was found in other countries. In gender-stratified analyses, unclean fuel use was associated with a 1.27 (95%CI, 1.13-1.44) times risk for males and 1.67 (95%CI, 1.44-1.94) times risk for females. Higher cataract risk attributed to unclean fuels was observed among those aged over 60 (1.45; 95%CI, 1.28-1.64) than people aged under 60 (1.39; 95%CI, 1.20-1.62). OR was higher in rural area (1.74; 95%CI, 1.51-2.00) than urban area (1.24; 95%CI, 1.09-1.41). Our results indicate that unclean fuels may be associated with self-reported cataract, but it varied among different LMICs. Higher risk was found in females, people older than 60 years old and those who live in rural areas. The result of this study provides useful information to support transition to clean household energy and eye health promotion in LMICs. Greater efforts should be taken to protect vulnerable populations.