Poverty and blindness: an intervention study to assess the impact of cataract surgery on poverty
- 1Department of Epidemiology and Public Health, London School of Hygiene & Tropical Medicine, London, UK
- 2Department of Infectious and Tropical Disease, London School of Hygiene & Tropical Medicine, London, UK
- 3Cataract Foundation of the Philippines, Bacolod, the Philippines
- 4Child Sight Foundation, Dhaka, Bangladesh
Objective
To assess the association between poverty and visually impairing cataract, and the impact of cataract surgery on alleviating poverty.
Setting
Centres in Kenya, Bangladesh and the Philippines. Baseline assessment was in 2005–2006, with follow-up one year later.
Participants
We recruited 596 cases and 481 controls, aged ≥50 years. Cases had visual acuity (VA) ≤3/36 in the better eye due to cataract. Controls were age-sex-community-matched to cases with normal vision (VA≥6/18). Controls and most cases (65%) were recruited through population-based surveys, with additional cases (35%) identified through population case finding. 413 cases underwent cataract surgery. At follow-up, we re-interviewed 345 operated cases and 552 controls.
Main outcome measures
Poverty was measured through: (1) per capita household expenditure (PCE), (2) household assets and (3) household self-rated wealth.
Results
At baseline, operated cases were significantly more likely than controls to be in the lowest quartile of PCE in Kenya (OR 3.5, 95% CI 1.1 to 11.2), Bangladesh (3.0, 1.5 to 6.1) and the Philippines (4.4, 1.9 to 10.3), with a significant dose–response relationship across quartiles of PCE. The pattern was similar for assets and self-rated wealth. At follow-up, PCE had increased significantly among the operated cases in all countries, but not among the controls. Operated cases were no longer more likely than controls to be in the lowest category of PCE in Kenya and the Philippines, and the association in Bangladesh was weakened (2.0, 1.0 to 4.0). Operated cases remained poorer than controls in terms of assets and self rated wealth, although the association was weaker than at baseline.
Conclusion
The Cataract Impact Study provides evidence that cases with cataract are poorer than controls, and that operating on the cataract may help to alleviate poverty.
