The Effects of Caffeinated Coffee on Intraocular Pressure

Massachusetts Eye and Ear Infirmary112 enrolled

Overview

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.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Masking

DOUBLE

Enrollment

112

Conditions

Primary Open Angle Glaucoma

Interventions

Caffeinated Coffee

Eligibility

Sex: ALLMin age: 40 YearsMax age: 89 YearsHealthy volunteers:

Medical Language ↔ Plain English

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

Outcomes

Primary Outcomes

Change in Intraocular Pressure at 60 Minutes

At the caffeinated coffee visit: Change in intraocular pressure at 60 minutes = intraocular pressure at 60 minutes post caffeinated coffee ingestion minus intraocular pressure at baseline prior to caffeinated coffee ingestion At the decaffeinated coffee visit: Change in intraocular pressure at 60 minutes = intraocular pressure at 60 minutes post decaffeinated coffee ingestion minus intraocular pressure at baseline prior to decaffeinated coffee ingestion

Time frame: Prior to coffee ingestion (baseline), 60 minutes post coffee ingestion

Change in Intraocular Pressure at 90 Minutes

At the caffeinated coffee visit: Change in intraocular pressure at 90 minutes = intraocular pressure at 90 minutes post caffeinated coffee ingestion minus intraocular pressure at baseline prior to caffeinated coffee ingestion At the decaffeinated coffee visit: Change in intraocular pressure at 90 minutes = intraocular pressure at 90 minutes post decaffeinated coffee ingestion minus intraocular pressure at baseline prior to decaffeinated coffee ingestion

Time frame: Prior to coffee ingestion (baseline), 90 minutes post coffee ingestion