Relationship Between Cataract Surgery and Mortality in Elderly Patients with Cataract: Nationwide Population-based Cohort Study in South Korea

Abstract There were a few studies showing conflicting findings with regard to the relationship between cataract surgery and all-cause mortality. It is uncertain whether cataract surgery could affect all-cause and cause-specific mortality in the Korean elderly population. We aim to investigate the relationship between cataract surgery and all-cause and cause-specific mortality in Korean elderly patients with cataract using the Korean National Health Insurance Service-Senior cohort database. Elderly patients (≥60 years) diagnosed with cataract from 2002 through 2012 were included. The baseline characteristics included demographics, and systemic and ocular comorbidities. Adjusted cox regression models with time-varying covariate for cataract surgery were used to assess the relationship between cataract surgery and mortality. The study cohort included 241,062 patients, of whom 127,491 were in the cataract surgery group and 113,121 were in the cataract diagnosis group. The incidence of all-cause mortality was 3.62 deaths/100 person-years and 3.19 deaths/100 person-years in the cataract surgery and cataract diagnosis groups, respectively. Cataract surgery was associated with a decreased hazard of all-cause mortality after adjusting for demographics, and systemic and ocular comorbidities (hazard ratio [HR],0.93;P<0.001). Protective association was noted between cataract surgery and mortality from vascular (HR,0.92;P<0.001) or neurologic (HR,0.64;P<0.001) causes in the adjusted model. Patients with cataract who were 85 years of age and older, women, those who had lower income and a Charlson comorbidity index score of 5 or more, or those without glaucoma revealed the largest reductions in mortality hazards resulting from cataract surgery. Further studies are needed to investigate the mechanisms underlying the relationship between cataract surgery and mortality.