Eyes with the highest IOPs and lowest diastolic BPs exhibited the fastest rates of structural progression. Photo: Getty Images.

Although perfusion pressure has been reported as a risk factor for the development and progression of glaucoma in many prognostic studies, this approach is flawed statistically due to the inseparability of blood pressure (BP) and intraocular pressure (IOP) in the determination of perfusion pressure. A recent study published in JAMA Ophthalmology explored the association of baseline BP measures with subsequent macular structural rates of change in a cohort of eyes with central or moderate to advanced glaucoma damage at baseline. They found that lower diastolic BP with higher IOP was associated with faster rates of change of ganglion cell complex (GCC) thinning.1

The cohort included 105 eyes from 105 patients with moderate to advanced glaucoma. The mean age, 10-2 visual field mean deviation and follow-up time were 66.9, -8.3dB and 3.6 years, respectively, and 67 patients were female. The racial and ethnic makeup of the cohort was 14.3% African American, 21.9% Asian, 11.4% Hispanic and 52.4% Caucasian based on patient self-report.

In multivariable analyses, female sex, history of taking systemic antihypertensive BP medications, higher IOP, thicker central corneal thickness, shorter axial length, higher contrast sensitivity at 12 cycles per degree and higher baseline 10-2 visual field mean deviation were associated with faster GCC thinning. Lower diastolic BP was associated with faster rates of GCC thinning at higher IOPs. For IOPs of 8mm Hg and 16mm Hg (10% and 90% quantiles, respectively), every 10mm Hg-lower increment of diastolic BP was associated with 0.011μm/year slower and -0.130μm/year faster rates of GCC thinning, respectively.

Because of these findings, the researchers noted, “Evaluating and addressing diastolic BP could be considered as a therapeutic measure in patients with glaucoma if supported by appropriate clinical trials.”

“Cardiovascular risk assessment and treatment of patients with glaucoma in conjunction with their internist may be indicated to optimize BP in these patients,” they wrote in their paper.1

A commentary also published in JAMA Ophthalmology highlighted, “For patients with treated systemic hypertension, avoiding nocturnal dosing of their antihypertensive agents may be a start.”

“Collaboration with patients’ primary care physicians to discourage overly aggressive treatment may be of benefit both with respect to glaucoma progression and mitigation of other drug-related adverse effects,” the author wrote in his commentary. “Continued research should focus on characterizing specific subsets of patients at greatest risk for progression driven by lower diastolic BP.”2

1. Mohammadzadeh V, Su E, Mohammadi M, et al. Association of blood pressure with rates of macular ganglion cell complex thinning in patients with glaucoma. JAMA Ophthalmol. February 9, 2023. [Epub ahead of print].

2. Tanna AP. Blood pressure and glaucoma—a complex relationship. JAMA Ophthalmol. February 9, 2023. [Epub ahead of print].