Effects of caffeine on intraocular pressure are subject to tolerance: a comparative study between low and high caffeine consumers
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Caffeine has a well-established effect on intraocular pressure (IOP) and ocular perfusion pressure (OPP); however, the possible differences between low- and high-caffeine consumers remain unknown.
In this placebo-controlled, double-blind, and balanced crossover study, 40 healthy individuals were divided in low- (n = 21) and high (n = 19)-caffeine consumers, according to their daily caffeine consumption. All participants ingested either caffeine (4 mg/kg) or placebo, and IOP and OPP were measured after 30, 60, and 90 min of ingesting caffeine or placebo. Subjective feelings of arousal were also obtained.
Caffeine induced an acute IOP rise (p < 0.001, ƞp2 = 0.408), whereas habitual caffeine demonstrated a mediating effect on the IOP changes induced by caffeine intake, with high-caffeine consumers showing a less accentuated IOP rise in comparison to low-caffeine consumers. The greatest IOP change induced by caffeine intake was reached after 90 min from capsule ingestion, being more accentuated for the low-caffeine consumers (+ 3.4 mmHg) than for the high-caffeine consumers (+ 1.2 mmHg). Consequently, the participants reported higher levels of perceived arousal after ingesting caffeine in comparison to placebo (p = 0.002, ƞp2 = 0.222); however, similar responses were given by high- and low-caffeine consumers (p = 0.256). Our data did not reveal any effect of caffeine consumption on OPP (p = 0.304).
These results suggest that IOP responsiveness to caffeine ingestion is subject to tolerance, which could have important implication in the management of glaucoma. This finding may be due to alterations in the adenosine receptor system caused by chronic caffeine consumption. Future studies are needed to assess if these findings are also applicable to patients with glaucoma.
KeywordsCaffeine Intraocular pressure Ocular perfusion pressure
The authors thank to all the participants who selflessly collaborated in this research.
Compliance with ethical standards
The experimental protocol followed the guidelines of the Declaration of Helsinki, and it was approved by the University of Granada Institutional Review Board (IRB approval, 438/CEIH/2017).
Conflict of interest
The authors declare that they have no conflicts of interest.
- Agnifili L, Mastropasqua R, Frezzotti P, Fasanella V, Motolese I, Pedrotti E, Iorio AD, Mattei PA, Motolese E, Mastropasqua L (2015) Circadian intraocular pressure patterns in healthy subjects , primary open angle and normal tension glaucoma patients with a contact lens sensor. Acta Ophthalmol 93:14–21. https://doi.org/10.1111/aos.12408 CrossRefGoogle Scholar
- Armstrong RA (2013) Statistical guidelines for the analysis of data obtained from one or both eyes. 7–14. https://doi.org/10.1111/opo.12009
- Chan MPY, Grossi CM, Khawaja AP, Yip JL, Khaw KT, Patel PJ, Khaw PT, Morgan JE, Vernon SA, Foster PJ, UK Biobank Eye and Vision Consortium (2016) Associations with intraocular pressure in a large cohort: results from the UK Biobank. Ophthalmology 123:771–782. https://doi.org/10.1016/j.ophtha.2015.11.031 CrossRefGoogle Scholar
- Corti R, Binggeli C, Sudano I, Spieker L, Hänseler E, Ruschitzka F, Chaplin WF, Lüscher TF, Noll G (2002) Coffee acutely increases sympathetic nerve activity and blood pressure independently of caffeine content role of habitual versus nonhabitual drinking. Circulation 106:2935–2940. https://doi.org/10.1161/01.CIR.0000046228.97025.3A CrossRefGoogle Scholar
- Grosso G, Micek A, Godos J, Sciacca S, Pajak A, Martínez-González MA, Giovannucci EL, Galvano F (2016) Coffee consumption and risk of all-cause, cardiovascular, and cancer mortality in smokers and non-smokers: a dose-response meta-analysis. Eur J Epidemiol 31:1191–1205. https://doi.org/10.1007/s10654-016-0202-2 CrossRefGoogle Scholar
- Grosso G, Godos J, Galvano F, Giovannucci EL (2017) Coffee, caffeine, and health outcomes: an umbrella review. Annu Rev Nutr 37:131–156. https://doi.org/10.1146/annurev-nutr-071816-064941 CrossRefGoogle Scholar
- Hoddes E, Zarcone V, Dement W (1972) Development and use of Stanford Sleepiness Scale (SSS). Psychophysiology 9:150Google Scholar
- Ismail A, Bhatti MS, Faye I, Lu CK, Laude A, Tang TB (2018) Pulse waveform analysis on temporal changes in ocular blood flow due to caffeine intake: a comparative study between habitual and non-habitual groups. Graefes Arch Clin Exp Ophthalmol 256:1711–1721. https://doi.org/10.1007/s00417-018-4030-9 CrossRefGoogle Scholar
- Jiwani AZ, Rhee DJ, Brauner SC, Gardiner MF, Chen TC, Shen LQ, Chen SH, Grosskreutz CL, Chang KK, Kloek CE, Greenstein SH, Borboli-Gerogiannis S, Pasquale DL, Chaudhry S, Loomis S, Wiggs JL, Pasquale LR, Turalba AV (2012) Effects of caffeinated coffee consumption on intraocular pressure, ocular perfusion pressure, and ocular pulse amplitude: a randomized controlled trial. Eye 26:1122–1130. https://doi.org/10.1038/eye.2012.113 CrossRefGoogle Scholar
- National Health and Medical Research Council (2010) Guidelines for the screening, prognosis, diagnosis, management and prevention of glaucoma. Commonwealth of Australia, Canberra. http://www.nhmrc.gov.au/publications/synopses/cp113syn.htm. Accessed June 2011
- van der Valk R, Webers CA, Schouten JS, Zeegers MP, Hendrikse F, Prins MH (2005) Intraocular pressure–lowering effects of all commonly used glaucoma drugs: a meta-analysis of randomized clinical trials. Ophthalmology 112(7):1177–1185Google Scholar