Is there an association between cataract surgery and age-related macular degeneration? Data from three population-based studies

PURPOSE: To determine whether cataract surgery is associated with an increased prevalence of age-related macular degeneration (AMD) in three independent population-based data sets. DESIGN: Cross-sectional study. METHODS: Data were used from the Salisbury Eye Evaluation (2,520 subjects from Salisbury, Maryland, aged 65 to 84 years), the Proyecto VER (4,774 Hispanic subjects from Arizona aged 40 years and older), and the Baltimore Eye Survey (4,396 subjects from Baltimore, Maryland, aged 40 and older). The main outcome measure was AMD as determined by retinal photographs or clinical examination. RESULTS: A history of cataract surgery was associated with an increased prevalence of late AMD in all three data sets after adjusting for age, race, sex, and smoking, but odds ratios (OR) were not individually statistically significant. The OR for the combined analysis was 1.7 (95% confidence interval: 1.1-2.6). Having a severe cataract in the eye was also associated with a slightly higher prevalence of late AMD, although the combined OR was not statistically significant (OR = 1.4; 95% confidence interval, 0.8%-2.4). Overall, increasing time since cataract surgery was not associated with late AMD. CONCLUSIONS: A history of cataract surgery may be associated with an increased prevalence of late AMD. However, having a severe cataract in the eye may also be associated with a higher prevalence of late AMD. Additional research is needed to investigate whether a causal relationship exists between cataract surgery and AMD or whether this relationship is due to residual confounding or bias.