The short term effects of coffee and caffeine on the cardiovascular and autonomic nervous systems
Completed
- Conditions
- Cardiovascular and autonomic nervous system functioningNervous System DiseasesAutonomic nervous system
- Registration Number
- ISRCTN11339389
- Lead Sponsor
- niversity of Westminster (UK)
- Brief Summary
Not available
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- Completed
- Sex
- All
- Target Recruitment
- 105
Inclusion Criteria
1. Voluntary recruits from the students, staff and associates of the University of Westminster
2. Non-medicated
3. Normotensive
4. Aged 18 to 63 years, either sex
5. Habitual caffeine users (consumption of tea or coffee on a daily basis) or non caffeine users (less than 3 servings per week)
Model 4 only:
6. Regular cyclists
Exclusion Criteria
1. Pregnant and breast feeding women
2. Hypertensive (blood pressure greater than 140/90 mmHg)
3. Users of prescribed medicines
For models 1 and 2:
4. Smokers
Study & Design
- Study Type
- Interventional
- Study Design
- Not specified
- Primary Outcome Measures
Name Time Method Pre-planned comparisons to placebo conditions:<br>1. The cardiovascular parameters derived from the Finometer recordings of the finger pulse contour (www.finapres.com): systolic, diastolic and mean blood pressure, heart rate, ejection time, diastolic interval, dp/dt, DPTI, SPTI, DPTI/SPTI, ejection time, stroke volume, cardiac output, total peripheral resistance, aortic impedance and arterial compliance<br>2. Breathing rate<br><br>Timepoints:<br>Model 1: recording 30 and 60 minutes after intervention; test session 15 minutes<br>Model 2: constant recording for 40 minutes after intervention
- Secondary Outcome Measures
Name Time Method 1. Pre planned comparisons of intervention effects in different postures<br>2. Variability analysis of Finometer derived cardiovascular parameters as appropriate in a post experimental analysis<br>3. Dosage relationships<br><br>Timepoints:<br>Model 1: recording 30 and 60 minutes after intervention; test session 15 minutes<br>Model 2: constant recording for 40 minutes after intervention