High Blood Pressure and Intraocular Pressure: A Mendelian Randomization Study

Area of Science:

• Ophthalmology
• Cardiovascular Research
• Genetics

Background:

• Blood pressure (BP) and intraocular pressure (IOP) are associated, but causality remains unclear.
• Glaucoma is a leading cause of blindness, and IOP is a major risk factor.
• Understanding the BP-IOP-glaucoma relationship can inform clinical practice and disease prevention.

Purpose of the Study:

• To determine if blood pressure causally influences intraocular pressure.
• To assess the causal effect of blood pressure on primary open-angle glaucoma (POAG) risk.

Main Methods:

• Utilized genome-wide association study (GWAS) data to identify single nucleotide polymorphisms (SNPs) associated with BP.
• Employed Mendelian randomization (MR) analyses to investigate causal relationships between BP, IOP, and POAG.
• Analyzed data from a large cohort with measured corneal-compensated IOP (IOPcc) and published GWAS summary statistics for POAG.

Main Results:

• Observational analyses showed a positive association between BP traits and IOPcc.
• Mendelian randomization analyses did not support a significant causal effect of BP on IOPcc.
• MR analyses also found no evidence of a causal effect of BP on the risk of POAG.

Conclusions:

• The causal effect of blood pressure on intraocular pressure and glaucoma risk appears to be modest or absent.
• Pleiotropic effects of SNPs associated with BP may complicate the interpretation of MR analyses.
• Further investigation is warranted to fully elucidate the complex interplay between BP, IOP, and glaucoma.