Effects of caffeine on blood flow in glaucoma patients and healthy individuals

Acute Changes in Optic Nerve Head (ONH) and Macular Blood Flow After Caffeine Consumption in Glaucoma Patients and Healthy Subjects: A Quantitative Optic Coherence Tomography Angiography (OCTA) Study

Not applicable Interventional Wills Eye · NCT03675412

This study tests how drinking caffeine affects blood flow in the eyes of people with glaucoma and healthy individuals.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment80 (estimated)
Ages18 Years to 90 Years
SexAll
SponsorWills Eye Academic / other
Locations1 site (Philadelphia, Pennsylvania)
Trial IDNCT03675412 on ClinicalTrials.gov

What this trial studies

This study investigates how caffeine consumption affects blood flow in the eyes of glaucoma patients and healthy subjects. Participants will ingest a 200 milligram caffeine tablet, and their peripapillary and macular blood flow will be assessed using optical coherence tomography angiography (OCTA) scans before and after caffeine intake. The study aims to understand the acute changes in blood flow, which may have implications for glaucoma management. By utilizing a non-invasive imaging technique, researchers hope to gather valuable data on the vascular effects of caffeine.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18 to 90 with a diagnosis of primary open angle glaucoma or healthy individuals without eye disease.

Not a fit: Patients with significant ocular or systemic diseases that could affect OCTA results or those with certain eye conditions will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide insights into how caffeine affects ocular blood flow, potentially influencing treatment strategies for glaucoma.

How similar studies have performed: While caffeine's effects on ocular blood flow have been studied, this specific approach using OCTA in glaucoma patients is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* age 18 to 90 years
* diagnosis of primary open angle glaucoma (Mild, Moderate and Advanced)
* healthy subjects with no eye disease

Exclusion Criteria:

* Diseases, ophthalmic or systemic, that are likely to affect OCTA results
* greater than moderate cataract
* nystagmus
* inability to look at target
* macular degeneration other than mild drusen or pigmentary changes
* diabetic retinopathy
* neovascular glaucoma or non-glaucoma optic neuropathies
* current macular edema, prior laser to retina, inflammatory retinopathy or choroidopathy
* keratoconus, corneal ectasia, central corneal scarring
* rheumatologic diseases or Raynaud's phenomena
* pregnant and lactating women
* mental illness or alcohol addiction
* pre-existing bladder symptoms, cardiac disease or sleep disorder
* refractive spherical diopter greater than 5 or cylinder greater than 3
* possible tolerance to caffeine (drinking more than 1 cup coffee per day).

Where this trial is running

Philadelphia, Pennsylvania

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Glaucoma, Primary Open AnglePrimary Open Angle GlaucomaOptical Coherence Tomography AngiographyCaffeineMacular Blood FlowPeripapillary Blood Flow
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.