Impact of cataract surgery on income in rural Southern China: the SUCCESS randomised controlled trial

Abstract

Abstract Purpose Visual impairment from cataract is closely associated with low income, but trial evidence regarding impact of surgery on income is lacking. We investigated whether cataract surgery could increase personal income. Methods This is a two-arm, parallel-group, open-label, randomised controlled trial (ClinicalTrials.gov, NCT03020056). Persons aged ≥50 years in rural Guangdong, China, with best-corrected visual acuity < 6/19 in both eyes due to cataract were randomly assigned (1:1) to receive surgery within four weeks (intervention group), or one year later (control). 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 years, 61.0% women) randomly assigned to intervention (n=146) or control (n=146),12 intervention group participants (8.22%) and one control (0.68%) did not receive the allocated intervention. By study closeout, 18 participants (6.16%) were lost to follow-up. Mean one-year intervention group income increase (USD2469 to 3588; change: USD1119) was significantly larger than for controls (USD2258 to 2052; change: USD-206), a between-group difference of USD1325 (relative increase 54.0%, 95% Confidence Interval [CI]: USD739 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 biological plausibility of the result.