Coffee project - Version 1.0
Research type
Research Study
Full title
Effects of coffee ingestion on platelets function
IRAS ID
167965
Contact name
Amedeo Chiribiri
Contact email
Sponsor organisation
King's College London
Duration of Study in the UK
0 years, 4 months, 26 days
Research summary
Myocardial perfusion tests are used to assess the blood flow (perfusion) to the heart muscles (myocardium) to detect areas with poor blood flow which, if left untreated, could cause a heart attack. Perfusion imaging is usually performed by (single photon emission computed tomography) SPECT or (magnetic resonance imaging) MRI. The most frequently used stressor is a vasodilator agent (adenosine, regadenoson or dypiridamole). All vasodilatory agents in use act either directly or indirectly on adenosine coronary receptors A2 (subtype-A).
Caffeine is the most widely consumed stimulant drug in the world and it is present in a variety of forms (medications, coffee, tea, soft drinks and chocolate). Caffeine binds and inactivates adenosine receptors and, if ingested in the 24 hours preceding the perfusion scan, has the potential to cause false/negative results and to limit the diagnostic accuracy of the test.
In this study, we aim to see if adenosine has any effect on platelets. This might in future allow doctors to test the efficacy of the drug just by analysing a blood sample.
We plan to test small blood samples from the patient before the scan, immediately after the administration of adenosine, and, after the end of a clinical scan, 30 minutes after the patient consumes a cup of complimentary coffee. We hypothesise that measurements of the activity of adenosine A2 receptors found on platelets can be used to predict sensitivity of coronary A2 receptors to vasodilatatory agents. Platelets A2 receptors are similarly affected by caffeine, and induce an intracellular second messenger (cAMP) response which we will measure in blood samples.REC name
West Midlands - Coventry & Warwickshire Research Ethics Committee
REC reference
15/WM/0282
Date of REC Opinion
6 Oct 2015
REC opinion
Further Information Favourable Opinion