Like diabetes, hypertension rates in the United States and worldwide have exploded. In fact, researchers estimate that 1.3 billion people worldwide suffer from it.1 For most primary care physicians, this is fairly easily handled by encouraging the patient to make lifestyle changes to control their blood pressure (BP), as well as prescribing BP-lowering medications. But, for eye care clinicians, lowering BP can have a dangerous side effect: elevated risk for glaucoma. Although it is weak, researchers point to a significant positive relationship between systemic blood pressure and intraocular pressure (IOP). “The relationship between glaucoma and systemic hypertension is multifaceted and often puzzling,” reads a new report, published in the Journal of Glaucoma.2

Part of that puzzle involves narrowing in on precisely what that relationship is. The authors relied on population-based studies, prospective longitudinal studies and randomized clinical trials to organize “evidence that lower systemic BP and lower ocular perfusion pressure are associated with greater glaucoma prevalence and a higher rate of glaucoma progression.” However, they are careful not to imply that treating systemic hypertension increases the risk of glaucoma.

Glaucoma specialist James Fanelli, OD, says that this research is more evidence to support the idea that optometrists “should consider systemic blood pressure a modifiable risk factor for both glaucoma development and glaucoma progression.”

But it isn’t a simple see-saw effect in which one goes up, causing the other to go down. One of the major findings of the research shows that “extreme falls in nighttime—but not daytime—systolic and diastolic blood pressure were significantly associated with a higher prevalence of glaucomatous optic neuropathy.”

Dr. Fanelli adds that patients should avoid taking BP medications at night, as a nocturnal drop in BP is often when IOP tends to increase.

Due to the nuanced nature of BP and IOP, the authors recommend a closer relationship between eye care and primary care physicians for patients straddling the hypertension-glaucoma risk.

“ODs don't interact with internal medicine and family practice and the medical community as a whole enough,” Dr. Fanelli adds. “We need to comanage and take an active role. It needs to be done all the time, effectively, competently and smoothly.”

1. Bloch MJ. Worldwide prevalence of hypertension exceeds 1.3 billion. J American Society of Hypertension: JASH. 2016;10(10):753-4.
2. De Moraes C, Cioffi G, Weinreb R, Liebmann J. Perspective: new recommendations for the treatment of systemic hypertension and their potential implications for glaucoma management. J Glaucoma. May 10, 2018. [Epub ahead of print].