Caffeine
Conditions
Keywords
coffee, caffeine, blood pressure, nutrigenetics, gene polymorphisms, Acute Cardiovascular and Neuropsychologic Effects
Brief summary
Cardiovascular and neuropsychologic effects of coffee are still debated. The precise mechanism underlying the actions of caffeine on the cardiovascular and neuropsychologic systems is incompletely understood and a considerable variability in the response to coffee drinking was observed, in part ascribable to a genetic trait. The aim of the study is to evaluate acute cardiovascular and neuropsychologic effects of coffee and explore whether such effects are influenced by the genetic asset of caffeine metabolism (by a polymorphisms of cytochrome P450 1A2), adenosine metabolism (by polymorphisms of adenosine receptor and adenosine monophosphate deaminase) or catecholamine receptors (by polymorphisms of adrenergic receptors).
Detailed description
Coffee is among the most widely consumed beverages worldwide. Despite the relationship between coffee consumption and the incidence of cardiovascular disease has been studied extensively, the effects of this drink on the cardiovascular apparatus and its role as a risk factor for coronary heart disease are still debated. Moreover, the effect of coffee on attention, sleep changes, anxiety and panic disorders was studied but a great variability was observed. Many of the known or suspected cardiovascular and neuropsychologic effects of coffee have been attributed to caffeine. The main mechanism of action of caffeine is to antagonize adenosine receptors; a secondary effect is the inhibition of phosphodiesterases, with the subsequent accumulation of cyclic adenosine monophosphate and a intensification of the effects of catecholamines. It is also well known that there is a considerable variability in the cardiovascular and neuropsychologic response to coffee drinking, explaining the inconsistency between different effects observed in the various studies. This variability may have a genetic basis. The aim of the study is to evaluate acute cardiovascular and neuropsychologic effects of coffee and explore whether such effects are influenced by the genetic asset of caffeine metabolism (by a polymorphisms of cytochrome P450 1A2), adenosine metabolism (by polymorphisms of adenosine receptor and adenosine monophosphate deaminase) or catecholamine receptors (by polymorphisms of adrenergic receptors).
Interventions
DIETARY_SUPPLEMENTCoffee
40 mL dose of a decaffeinated preparation spiked with the addition of caffeine, at a dose of 3 mg/kg
DIETARY_SUPPLEMENTDecaffeinated coffee
40 mL dose of decaffeinated coffee
Sponsors
Institute for Scientific Information on Coffee
Italian Istituto Nazionale Ricerche Cardiovascolari
G. d'Annunzio University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
MALE
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* Age between 18 and 40 years * Males (to avoid variation due to female hormonal cycle) * No known active ongoing disease (apparent good health) * Non-smokers (to avoid contributory effects of nicotine or other tobacco alkaloids to caffeine effects or tolerance) * Average coffee intake (not less than one cup/day and not greater than three cups/day)
Exclusion criteria
* Treatment with any drug with known activity on the adrenergic system * Hypertension * Therapy with sympathomimetic drugs, theophylline, alpha- or beta-blockers, any antihypertensive therapy * Body mass index (BMI) \> 30 kg/m2 (obesity) * BMI \< 18.5 kg/m2
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in platelet aggregation | From baseline to 30 minutes and 2 hours after coffee or decaffeinated alternatively | Light transmission aggregometry (LTA) induced by ADP and apinephrine. Platelet function analyzer (PFA) by collagen-ADP and collagen-epinephrine cartridges. |
| Change in cognitive tasks measures | From 30 minutes until 2 hours after coffee or decaffeinated alternatively | Low intensity task of focused attention and choice reaction times (Categorical Search Task). More demanding response interference tasks (Letter Flanker Task). Classic interference task (Stroop Test). |
| Change in blood pressure | From baseline until 2 hours after coffee or decaffeinated alternatively | — |
| Change in heart rate | From baseline until 2 hours after coffee or decaffeinated alternatively | — |
Secondary
| Measure | Time frame |
|---|---|
| Change in plasma caffeine concentration | From baseline to 30 minutes and 2 hours after coffee or decaffeinated alternatively |
| Change in plasma adrenaline and noradrenaline concentration | From baseline to 30 minutes and 2 hours after coffee or decaffeinated alternatively |
Countries
Italy
Outcome results
None listed