Risk of Age-Related Macular Degeneration in Patients with Exfoliation Syndrome: The Utah Project on Exfoliation Syndrome (UPEXS)

Objective: To investigate any relationships between exfoliation syndrome or exfoliation glaucoma and age-related macular degeneration utilizing the Utah population database. Design: This was a retrospective, case–control cohort study. Subjects, Participants, and/or Controls: We identified 3405 patients diagnosed with exfoliation syndrome (XFS) or exfoliation glaucoma (XFG) during a dilated eye exam within the UHealth system from 1996 to 2021, whose dry or wet age-related macular degeneration (AMD) status was assessed. A population-based control pool of 257,714 UHealth patients with no XFS/XFG diagnosis and a dilated eye exam history from 1996 to 2021 was compiled, with its patients randomly selected and individually matched 3:1 to cases based on sex and age at index diagnosis of their respective case. Methods: A covariate analysis was performed of characteristics and risk factors associated with XFS/XFG, which included race/ethnicity, residence location, partner/marital status, and family history of XFS/XFG, obesity, tobacco use, alcohol use, osteoporosis/vitamin D deficiency, primary/essential hypertension, ocular hypertension, and cataract surgery. Main Outcome Measure: We studied the trends of non-exudative (dry) or exudative (wet) AMD in a large Utah population study of XFS/XFG patients and controls. Results: Of 3396 XFS/XFG patients, as well as 10,179 individually matched 3:1 control patients, 64% were female and the average age of XFS onset was 74.3 yrs. In a univariate model, we observed a very modest increased risk of wet AMD in XFS/XFG patients (odds ratio, OR = 1.14, 95% confidence interval (CI) 0.99–1.32), which did not achieve statistical significance (p = 0.07). After adjusting for the main effects of potential confounders, there was no greater presentation of AMD in XFS/XFG patients when compared with controls (dry AMD: OR = 0.94, 95% CI 0.85–1.05, p = 031; wet AMD: OR = 0.98, 95% CI 0.83–1.14, p = 0.76). In XFS/XFG patients compared to controls, the risk of having cataract surgery was elevated (OR = 2.39, 95% CI 2.18–2.62). However, after accounting for an interaction with AMD, XFS/XFG patients who underwent cataract surgery did not exhibit an increased risk of either dry or wet AMD (dry AMD: OR = 0.91, 95% CI 0.80–1.03; wet AMD: OR = 0.89, 95% CI 0.75–1.07). The risk of AMD in XFS/XFG patients vs. controls showed no association with osteoporosis/vitamin D deficiency for dry (OR 0.78 95% CI 0.66–0.92 p = 0.004) or wet AMD (OR = 0.72 95% CI 0.56–0.92 p = 0.01), while we found a borderline positive association with both dry and wet AMD if they had osteoporosis/vitamin D deficiency. Conclusion: Using the Utah Population Database, we found that a cataract surgery history significantly impacts the association between AMD and XFS, and that vitamin D deficiency/osteoporosis is a significant confounder of the association. However, no direct association between XFS and AMD was found in this study.