Forskning

June 11, 2012

Effects of caffeinated coffee consumption on intraocular pressure, ocular perfusion pressure, and ocular pulse amplitude: a randomized controlled trial

A Z Jiwani et al, 2012, Effects of caffeinated coffee consumption on intraocular pressure, ocular perfusion pressure, and ocular pulse amplitude: a randomized controlled trial, Eye, published online ahead of print.

ABSTRACT
Purpose:  To examine the effects of caffeinated coffee consumption on intraocular pressure (IOP), ocular perfusion pressure (OPP), and ocular pulse amplitude  (OPA) in those with or at risk for primary open-angle glaucoma (POAG).

Methods:  We conducted a prospective, double-masked, crossover, randomized controlled trial with 106 subjects: 22 with high tension POAG, 18 with normal tension POAG, 20 with ocular hypertension, 21 POAG suspects, and 25 healthy participants. Subjects ingested either 237 ml of caffeinated (182mg caffeine) or decaffeinated (4mg caffeine) coffee for the first visit and the alternate beverage for the second visit. Blood pressure (BP) and pascal dynamic contour tonometer measurements of IOP, OPA, and heart rate were measured before and at 60 and 90 min after coffee ingestion per visit. OPP was calculated from BP and IOP measurements. Results were analysed using paired t-tests. Multivariable models assessed determinants of IOP, OPP, and OPA changes.

Results:  There were no significant differences in baseline IOP, OPP, and OPA between the caffeinated and decaffeinated visits. After caffeinated as compared with decaffeinated coffee ingestion, mean mmHg changes (±SD) in IOP, OPP, and OPA  were as follows: 0.99 (±1.52, P<0.0001), 1.57 (±6.40, P=0.0129), and 0.23 (±0.52, P<0.0001) at 60 min, respectively; and 1.06 (±1.67, P<0.0001), 1.26 (±6.23, P=0.0398), and 0.18 (±0.52, P=0.0006) at 90 min, respectively. Regression analyses revealed sporadic and inconsistent associations with IOP, OPP, and OPA changes.

Conclusion:  Consuming one cup of caffeinated coffee (182mg caffeine)statistically increases, but likely does not clinically impact, IOP and OPP in those with or at risk for POAG.