Impact of cataract surgery on depression and cognitive function: Systematic review and meta-analysis

Importance: In elderly people, visual impairment is associated with depressive symptoms and cognitive decline. However, the impact of cataract surgery on depression and cognitive impairment is still controversial. Background: To evaluate the effect of cataract surgery on depression and cognitive status in the elderly. Design: This study was a meta-analysis. Participants: Patients with age-related cataract who underwent cataract surgery were recruited for this study. Methods: A literature search was performed on PubMed, Scopus and Web of Science. Data were extracted from selected studies by two independent reviewers. The pooled standardized mean difference (SDM) was estimated using a random-effects model. Heterogeneity was evaluated using the Q and I2 tests. Multiple sensitivity analyses and assessment of publication bias were performed. Main outcome measures: The main outcome was a report of a measure of depression or cognitive impairment before and after surgery. Results: Sixteen studies were included: 14 of them reported data on depression and 9 of them on cognitive function. Depression significantly decreased after surgery (SDM = 0.460; 95% CI: 0.223-0.697; P < .001). In six controlled studies, the reduction of depression was higher in the surgery group than in the control group (SDM = 0.161; 95% CI: 0.027-0.295; P = .019). Cognitive function significantly improved after surgery (SDM = 0.254; 95% CI: 0.120-0.388; P < .001). In four controlled studies, the improvement of cognitive function was higher in the surgery group than in the control group (SDM = 0.188; 95% CI: 0.002-0.374; P = .048). Results were stable after sensitivity analyses. Conclusions and relevance: This meta-analysis provides evidence that cataract surgery has a positive effect on depression and cognitive function in the elderly.