Risk factors for age-related macular degeneration: Updated systematic review and meta-analysis

Background: Age-related macular degeneration (AMD) is a leading cause of irreversible visual loss in the elderly population, affecting millions of the people worldwide. AMD has a substantial effect on quality of life in older individuals. Understanding and identifying risk factors are crucial for developing preventive strategies. Methods: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a comprehensive literature search across databases including PubMed, Scopus, and Web of Science up to January 28, 2024. Studies were selected using standardized inclusion and exclusion criteria, and the quality of the studies was assessed via the Newcastle Ottawa Scale. Meta-analysis was conducted using Review Manager software to pool the odds ratio (OR) of each included risk factors at the 95% confidence interval (CI). Results: Eighteen of the 2640 identified studies met the inclusion criteria for the meta-analysis. Older age compared to younger age, male gender compared to female gender, smoking, hypertension, cardiovascular diseases, and diabetes were statistically significant predictors for AMD occurrence, with ORs of 1.11 (95% CI = 1.06–1.15, P < .00001), 1.63 (95% CI = 1.13–2.35, P = .009), 1.86 (95% CI = 1.33–2.6, P = .0003), 1.24 (95% CI = 1.09–1.4, P = .0007), 1.44 (95% CI = 1.11–1.87, P = .006), and 1.44 (95% CI = 1.3–1.6, P < .00001), respectively. Other factors, such as body mass index, cerebrovascular diseases, cholesterol, and triglycerides, were not significantly associated with AMD. Conclusion: This updated meta-analysis highlights the significance of modifiable risk factors for AMD, including smoking, hypertension, cardiovascular diseases, and diabetes. Early identification of AMD accompanied by strategic management of these modifiable risk factors may preserve patients’ visual acuity without advancing to advanced stages.