The Impact of Caffeine on Brachial Endothelial Function in Healthy Subjects and in Patients With Ischemic Heart Disease
- Registration Number
- NCT00564824
- Lead Sponsor
- Sheba Medical Center
- Brief Summary
Prior work (Chris, M. et al, Clinical Science 2005; 109, 55-60) has demonstrated that drinking a cup of coffee (80-100 mg of caffeine) an hour before endothelium-dependent FMD (flow-mediated dilatation) of the brachial artery, effects endothelial function in healthy adults subjects.
This effect might be attributed to caffeine, given that decaffeinated coffee (\<2 mg of caffeine) was not associated with any change in endothelial performance.
In the current study we intend to further examine the impact of caffeine on brachial endothelial function among healthy subjects \& in patients with proven ischemic heart disease.
- Detailed Description
Background:
Prior work (Chris, M. et al, Clinical Science 2005; 109, 55-60) has demonstrated that drinking a cup of coffee (80-100 mg of caffeine) an hour before endothelium-dependent FMD (flow-mediated dilatation) of the brachial artery, effects endothelial function in healthy adults subjects.
This effect might be attributed to caffeine, given that decaffeinated coffee (\<2 mg of caffeine) was not associated with any change in endothelial performance.
In the current study we intend to further examine the impact of caffeine on brachial endothelial function among healthy subjects \& in patients with proven ischemic heart disease.
Aim:
To evaluate the impact of 200 mg caffeine tablet intake (equivalent to 2 cups of coffee), compared to placebo on brachial endothelial function in healthy subjects \& in patients with proven ischemic heart disease.
Methods:
1. Patients will be invited for two endothelial function tests 1 week apart.
2. ECG, heart rate \& blood pressure will be recorded at rest prior to each test.
3. Following overnight fasting and discontinuation of all medications for ≥ 12 hours and absence of \> 48 hour caffeine consumption, patients will receive 200 mg of caffeine tablets or placebo, in a double-blind, cross-over study design. An hour later the patient will undergo endothelium-dependent flow-mediated dilation (FMD) and endothelium-independent, nitroglycerin (NTG)-mediated vasodilation will be assessed non-invasively in the brachial artery, using a high resolution (15 MHz) linear array ultrasound.
4. Prior to and after the FMD, blood will be drawn to test caffeine levels, adiponectin, CBC, electrolytes, CRP and lipids.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 80
- Patients with documented ischemic heart disease
- Healthy subjects who are not heavy regular coffee drinkers
- Patients with unstable angina pectoris
- Patients with acute or chronic heart failure
- Patients with cardiac arrhythmia
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Placebo Placebo Patients with prior history of coronary artery disease (CAD) (myocardial infarction, cerebrovascular accident, coronary angioplasty, S/p CABG operation) who will be given on the first day either caffeine of placebo tablet and 1-2 hours thereafter a brachial artery endothelial function testing (BRT) will be assessed for measuring the FMD. After 1 week the patients will come for a second BRT on placebo/caffeine tablets. If the patient received caffeine tablet the first BRT, he will be receiving placebo tablet the second week, however, if the patient received placebo the first BRT, a caffeine tablet will be given prior to the second BRT. CAD patients Caffeine Patients with prior history of coronary artery disease (CAD) (myocardial infarction, cerebrovascular accident, coronary angioplasty, S/p CABG operation) who will be given on the first day either caffeine of placebo tablet and 1-2 hours thereafter a brachial artery endothelial function testing (BRT) will be assessed for measuring the FMD. After 1 week the patients will come for a second BRT on placebo/caffeine tablets. If the patient received caffeine tablet the first BRT, he will be receiving placebo tablet the second week, however, if the patient received placebo the first BRT, a caffeine tablet will be given prior to the second BRT.
- Primary Outcome Measures
Name Time Method Flow-mediated dilation (FMD) as surrogate of brachial artery endothelial function 1-2 hours post caffeine (or placebo)
- Secondary Outcome Measures
Name Time Method Markers of inflammation such as hs-CRP, Il6, homocysteine, serum caffeine level 1-2 hours post caffeine or placebo
Trial Locations
- Locations (1)
Heart Institute, Chaim Sheba Medical Center
🇮🇱Tel Hashomer, Israel