Impact of Cataract Surgery on Income in Rural Southern China: The SUCCESS Randomized Controlled Trial

Abstract

Purpose: Visual impairment from cataracts is closely associated with low income, but trial evidence regarding the impact of surgery on income is lacking. We investigated whether cataract surgery could increase personal income. Design: A 2-arm, parallel-group, open-label, randomized controlled trial (ClinicalTrials.gov, NCT03020056). Methods: Persons aged 50 years or older in rural Guangdong, China, with best-corrected visual acuity <6/19 in both eyes due to cataracts were randomly assigned (1:1) to receive surgery within 4 weeks (intervention group), or 1 year later (control group). All participants were interviewed at baseline and end-line regarding demographic characteristics, income, and quality of life. Results: Among the 292 eligible persons (5.40%, mean age = 74.0 y, 61.0% women) randomly assigned to intervention (n = 146) or control (n = 146) groups, 12 participants (8.22%) in the intervention group and 1 (0.68%) in the control did not receive the allocated intervention. By study closeout, 18 participants (6.16%) were lost to follow-up. The mean 1-year income increase of the intervention group ($2469–$3588; change = $1119) was significantly larger than that of the controls ($2258–$2052; change = $–206), a between-group difference of $1325 (relative increase = 54.0%; 95% CI = $739 to $1911; P < 0.001). In multivariable modeling, intervention group membership was associated with greater income increase (β = 1143.2; 95% CI = 582.0 to 1704.3; P < 0.001). Greater improvement in best-corrected visual acuity was associated with income increase in univariable modeling (β = 1626.9; 95% CI = 1083.6 to 2170.1; P < 0.001). Conclusions: Cataract surgery substantially increases personal income in rural China, offering a strategy for poverty alleviation. The strong association between increased income and change in visual acuity enhances the biological plausibility of the result.