Risk of Parkinson's disease in glaucoma patients: a systematic review and meta-analysis.

Objective: To conduct a systematic review and meta-analysis to evaluate the relationship between glaucoma and the risk of Parkinson's disease.

Methods: A systematic search of databases including MEDLINE, EMBASE, and CINAHL were conducted. Grey literature search, including Dissertations and Theses databases and conference abstracts, was performed. Duplicates were removed, and two independent reviewers conducted the screening. We included any primary observational studies that examined the relationship between glaucoma and Parkinson's disease. Study characteristics along with relevant outcome measurements such as hazard ratio (HR), odds ratio (OR), and prevalence were extracted. Meta-analysis using STATA 15.0 was performed, and the presence of heterogeneity was determined using statistics, -test, and -value.

Results: A total of 746 citations were found through the databases and grey literature searches. After screening, five studies met the inclusion criteria, and three studies were included in the meta-analysis. There was a non-significant hazard of developing Parkinson's disease (Hazard Ratio = 1.13, 95% CI: [0.99, 1.29]) in patients with glaucoma compared to controls.

Discussion: The hazard of developing Parkinson's disease was non-significantly different for those with glaucoma compared to controls; however, there were not enough studies available to draw definitive conclusions.