The Effects of Caffeinated Coffee on Intraocular Pressure

The Effects of Caffeinated Coffee on Intraocular Pressure

High intraocular pressure (IOP) is a known risk factor for developing primary open-angle glaucoma (POAG). There is controversy in the literature regarding the degree to which caffeine influences IOP, with some studies reporting minimal changes in IOP while others report up to 4 mmHg increases. To date there are no double-masked randomized controlled trials that examine acute caffeinated coffee's effects on IOP in patients with or at risk for primary open-angle glaucoma. The investigators aim to better understand the relationship between acute caffeinated coffee (vs decaffeinate coffee) consumption and IOP in a double-masked, crossover randomized controlled clinical trial.

Inclusion Criteria:

• 40-89 yrs
• POAG for cases or no forms of glaucoma for controls
• Willingness to drink coffee
• Consent signed

Exclusion Criteria:

• Age less than 40 or greater than 89 yrs
• all forms of glaucoma other than POAG
• any condition inappropriate for tonometry (ie corneal disease, LASIK)
• unable or unwilling to give consent
• unable or unwilling to drink coffee
• pregnancy