Effect of caffeine on vessel density in healthy subjects assessed with optical coherence tomography angiography

Abstract

Purpose : Caffeine is a readily available and regularly used neurostimulant with effects on systemic vasculature. There is limited data on the effects on retinal vasculature with some reports indicating vessel constriction. We aim to evaluate if caffeine alters the macular vascular density of the superficial capillary plexus (SCP) on optical coherence tomography angiography (OCTA).

Methods : This IRB-approved study prospectively recruited healthy, low caffeine users who consumed, on average, less than 136 mg of caffeine daily. We analyzed 22 eyes from 11 individuals between the ages of 18 and 40, with no preexisting ocular conditions. Baseline 3x3mm and 6x6mm OCTA scans centered on the fovea as well as 6x6mm scans centered on the optic nerve head (ONH) were obtained. Participants were then given a 200mg caffeine pill. Scans were repeated at 60 and 120 minutes after caffeine administration. All images were analyzed with the Advanced Retina Imaging (ARI) network software (Carl Zeiss Meditec, Dublin, CA) superficial perfusion density algorithm for vascular density (VD) defined as the total area of perfused vasculature in a region of measurement. Ordinary one-way ANOVA of each group was performed using GraphPad Prism Version 9.3.0.

Results : Mean age was 24.6 +/- 4.6 years and 82.2% were females. For the 3x3 mm scans, the VD was 31.55%, 31.57%, and 32.06% at baseline, 60, and 120 minutes respectively (p=0.9993 and p=0.7933). For the 6x6 mm scans, the VD was 38.16%, 39.09%, and 39.04% at baseline, 60, and 120 minutes respectively (p=0.7300 and p=0.7546). For the ONH scans, the VD was 41.06%, 39.74%, and 41.44% at baseline, 60, and 120 minutes respectively (p=0.5649 and p=0.9498).

Conclusions : Our results indicate no change in the SCP vessel density after 200 mg caffeine. Larger placebo-controlled studies are needed to confirm this finding.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.