Using data from the Gutenberg Health Study, researchers examined the effect of systemic anti-hypertensive medications on IOP.

This population-based, prospective cohort study included 13,527 patients who were on a wide range of cardiovascular medications: peripheral vasodilators, diuretics, β-blockers (overall, selective, and non-selective), calcium channel blockers, renin–angiotensin blockers (overall, ACE inhibitors and angiotensin-receptor blockers), nitrates, other antihypertensive medications, aspirin, and statins.

IOP was measured using a non-contact tonometer. Any patient on topical IOP-lowering medications or with a history of any ocular surgery was excluded.

A multivariate analysis found no statistically significant association between the use of oral anti-hypertensive medications and IOP in non-glaucomatous patients.

Specifically, in contrast to prior studies, the authors found no association between β-blockers and lower IOP, though there was a slight trend towards lower IOP in patients on non-selective β-blockers. There was also no statistically significant association between ACE inhibitors and IOP.

This study was limited by its observational design. The primary aim of the original study, the Gutenberg Health Study, was to study cardiovascular health, not effects of medications on IOP. Researchers did not study the effects of oral β-blockers in conjunction with topical IOP-lowering β-blockers or other IOP-lowering medications.

It has long been believed that oral β-blockers lower IOP, and some physicians avoid topical β-blockers in patients on oral medications, feeling there won't be much benefit. While IOP lowering may occur in the short term with oral β-blockers, this long-term study indicates that oral medications do not have an affect on IOP. As a result, physicians may elect to use topical β-blockers more in this population.