Sasankadhar Reddy
Junior Resident, Department of Ophthalmology, Sri Devaraj Urs Medical College, Kolar, India
Chaitra MC
Professor, Department of Ophthalmology, Sri Devaraj Urs Medical College, Kolar, India.
Manohar Gowda
Assistant Professor, Department of General Medicine, Sri Devaraj Urs Medical College, Kolar, India
Background: Primary open-angle glaucoma (POAG) is a progressive optic neuropathy in which vascular factors, including systemic hypertension and ocular perfusion pressure (OPP), may contribute to glaucomatous damage. The relationship between essential hypertension, OPP, and glaucoma severity remains complex.
Objectives: To compare OPP between POAG patients with essential hypertension and normotensive POAG patients and to evaluate differences in structural and functional parameters of glaucoma severity between the groups.
Methods: This hospital-based case–control study included 84 patients with POAG attending the Department of Ophthalmology, R. L. Jalappa Hospital and Research Centre, Kolar, over one year. Participants were divided into two groups of 42 each based on hypertension status. Systemic blood pressure, intraocular pressure (IOP), and OPP were assessed. Glaucoma severity was evaluated using optic disc examination, Humphrey visual field analysis, and optical coherence tomography measurements of retinal nerve fibre layer (RNFL) and ganglion cell complex (GCC) thickness. Appropriate statistical tests were applied, with p<0.05 considered significant.
Results: Mean OPP was significantly higher in hypertensive patients than in normotensive patients (54.16 ± 5.15 versus 44.58 ± 4.04 mmHg; p<0.001), despite comparable IOP
(p=0.838). Hypertensive patients demonstrated significantly greater cup-to-disc ratios (p=0.036), reduced superior RNFL thickness (p=0.010), and reduced inferior GCC thickness (p=0.049). Although visual field mean deviation, pattern standard deviation, and visual field index indicated numerically greater functional impairment among hypertensive patients, these differences were not statistically significant.
Conclusion: Essential hypertension was associated with higher calculated OPP and greater structural glaucomatous abnormalities despite comparable IOP. Higher daytime OPP may not necessarily indicate protection against optic nerve damage. Assessment of systemic vascular factors alongside conventional glaucoma parameters may support comprehensive POAG management.
