The association of lower ocular perfusion pressure with glaucoma severity independent of intraocular pressure

Purpose: To investigate the relationship between systemic hypertension, ocular perfusion pressure (OPP), and intraocular pressure (IOP) with glaucoma severity, with a secondary analysis on the impact of antihypertensive medication. Design: Cross-sectional observational study. Methods: A total of 75 patients (75 eyes) with primary open-angle glaucoma (POAG) were included. One eye per patient was randomly selected for analysis. All participants underwent comprehensive ophthalmic examination and a single time-point systemic blood pressure (BP) measurement. Data on antihypertensive medication usage were also collected. Glaucoma was staged as early, moderate, or advanced. Key variables included systolic/diastolic blood pressure (SBP/DBP), mean arterial pressure (MAP), IOP, and estimated OPP. Analysis of variance and Pearson’s correlation were used. A sub-group analysis compared hemodynamic parameters between patients on antihypertensive medication and those who were not. Results: The mean age was 53.99 ± 6.53 years. While mean IOP did not differ significantly across glaucoma stages ( P = 0.71), mean OPP (57.59 to 50.65 mmHg), diastolic perfusion pressure (DPP), DBP, and MAP all decreased significantly with increasing glaucoma severity ( P < 0.001). In a sub-group analysis, patients on antihypertensive medication ( n = 42) had a significantly lower mean OPP (53.21 ± 5.98 mmHg) compared to those not on medication (57.85 ± 5.89 mmHg; P = 0.002), despite having similar in-office SBP. Conclusions: Lower OPP, DPP, DBP, and MAP were significantly associated with advanced glaucoma severity. Patients on antihypertensive medication had lower mean OPP, suggesting they may be at higher risk for perfusion-related damage not captured by in hospital BP readings. This highlights the importance of considering the hemodynamic effects of medication in glaucoma management.