Please use this identifier to cite or link to this item:
Title: Caffeine intake is associated with pupil dilation and enhanced accommodation
Authors: Abokyi, S 
Owusu-Mensah, J
Osei, KA
Issue Date: 2017
Publisher: Nature Publishing Group
Source: Eye, 2017, v. 31, no. 4, p. 615-619 How to cite?
Journal: Eye 
Abstract: Purpose It is purported that caffeine, an autonomic stimulant, affects visual performance. This study sought to assess whether caffeine intake was associated with changes in pupil size and/or amplitude of accommodation. Patients and methods A double-masked, crossover study was conducted in 50 healthy subjects of age range 19 to 25 years. Subjects were randomized to treatments such that subjects consumed either 250 mg caffeine drink or vehicle on separate days. Amplitude of accommodation was measured by the push-up technique, and pupil size using a millimeter ruler fixed to a slit lamp biomicroscope in dim illumination (5 lux). Amplitude of accommodation and pupil size were taken at baseline, and at 30, 60 and 90 min time points post treatment. Repeated measures one-way ANOVA and paired t-test were used in analyzing data. Results Amplitude of accommodation and pupil size after caffeine intake were significantly greater than vehicle (P<0.001) at each time point. Consumption of the caffeine beverage was associated with significant increases in amplitude of accommodation and pupil size with time (P<0.001). Amplitude of accommodation rose from 12.4 (+/- 2.2 D) at baseline to 15.8 (+/- 2.6 D) at 90 min. Similarly, pupil size increased from 3.4 (+/- 0.4 mm) at baseline to 4.5 (+/- 0.72 mm) at 90 min. Consumption of vehicle was not associated with increase in amplitude of accommodation or pupil size with time. Conclusion Pupil size and accommodation are affected after ingestion of caffeine. This study suggests caffeine may have some influence on visual functions.
ISSN: 0950-222X
EISSN: 1476-5454
DOI: 10.1038/eye.2016.288
Appears in Collections:Journal/Magazine Article

View full-text via PolyU eLinks SFX Query
Show full item record


Last Week
Last month
Citations as of Dec 13, 2018

Page view(s)

Last Week
Last month
Citations as of Dec 9, 2018

Google ScholarTM



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.