Cognitive Trajectory Before and After Cataract Surgery: A Population-Based Approach.

Background: Cataract surgery is the most common surgical procedure performed for older US adults. Cataracts are associated with poor cognition and higher rates of dementia, but whether cataract surgery improves cognition for US older adults is not known. We examined the relationship between cataract surgery and long-term change in cognition in the Health and Retirement Study, a population-based study of older US adults linked with Medicare billing data.

Methods: We analyzed community-dwelling participants who underwent cataract surgery between 2000 and 2018, propensity-matched on age, sex, education (four levels), diabetes status (four levels), pre-procedural latent cognition, vision impairment, and interview timing and mode to older adults who did not have cataract surgery during the study period. Cataract surgery date was ascertained using Medicare billing data. We calculated latent value of cognition using biennial self/proxy cognitive assessments, and used linear mixed effects models adjusting for demographic and health factors to model cognition from 5 years before, to 5 years after, cataract surgery (or a simulated event, for controls). The primary measure was difference-in-differences estimate of latent cognition comparing the year prior, to the year after, cataract surgery or a simulated event.

Results: We analyzed 4384 older adults who underwent cataract surgery and 4384 matched controls (mean [SD] age 76.1 [6.8] years, 62.0% women, 83.9% non-Hispanic white). Across the first postoperative year, cataract surgical participants declined 0.002 (-0.002 to 0.006) units faster than nonsurgical controls (p = 0.37), equivalent to 8 (-10 to 26) days more cognitive aging. Post hoc subgroup analyses also found no difference in cognition for groups stratified by pre-procedural latent cognition (i.e., normal vs. cognitively impaired) or vision (i.e., vision-impaired vs. intact).

Conclusion: Under typical United States practice, cataract surgery for older patients was not significantly associated with cognitive improvement or decline in the year after, compared with the year before, surgery.