Advanced Search

Study Preview



Study Title and Description

The effect of caffeine on dilated cerebral circulation and on diagnostic CO2 reactivity testing.



Key Questions Addressed
1 For [population], is caffeine intake above [exposure dose], compared to intakes [exposure dose] or less, associated with adverse effects on cardiovascular outcomes?
  • Comments Comments (
    0
    ) |

Primary Publication Information
  • Comments Comments (
    0
    ) |
TitleData
Title The effect of caffeine on dilated cerebral circulation and on diagnostic CO2 reactivity testing.
Author M Blaha,V Benes,CM Douville,DW Newell,
Country
Year 2007
Numbers

Secondary Publication Information
There are currently no secondary publications defined for this study.


Extraction Form: Cardiovascular Design
Design Details
Question... Follow Up Answer Follow-up Answer
What outcome is being evaluated in this paper? Cardiovascular
  • Comments Comments (
    0
    ) |
What is the objective of the study (as reported by the authors)? The aim of this study was to investigate the effect of caffeine on dilated cerebral circulation and to determine if these vessels are still able to constrict as a consequence of caffeine stimulation.
  • Comments Comments (
    0
    ) |
Provide a general description of the methods as reported by the authors. Information should be extracted based on relevance to the SR (i.e., caffeine related methods) Subjects Seventeen healthy adult volunteers (7 male and 10 female) with no history of cerebrovascular diseases, participated in this study. Their ages were between 25 and 59 years (mean 39.9 +/- 8.7). They were advised not to drink coffee or caffeine-containing beverages for 6 h prior to the test. Hemodynamics Measurement A headband was placed on the subject’s head, allowing a secure attachment of a left and right 2.0 mHz pulsed wave Doppler transducer over the temporal bone windows. Velocities (time averaged maximum or Vmean) from both middle cerebral arteries were continuously monitored at a depth providing the best signal (50–55 mm) using TCD equipment (MultidopX, DWL, Sipplingen, Germany) and standard vessel identification criteria. Non-invasive blood pressure and heart rate were recorded with a pneumatic cuff (CBM-7000, ColinCorp., San Antonio, TX, USA). End-tidal CO2 concentration was measured with a CO2 analyzer (Datex 223, Puritan-Bennett Corp., MA, USA). Testing Protocol The vasomotor reactivity was measured for each subject. Thereafter, the subject was asked to drink 350 mL of drip coffee, which contained 300 mg of caffeine. A repeat measurement of vasomotor reactivity was done 30 minutes after coffee ingestion. The dose of caffeine in drip coffee was measured by high pressure liquid chromatography (HPLC). Statistical Analysis Data were reported as mean +/- standard deviation (SD) and the changes in velocity in the middle cerebral artery (VMCA) were calculated as differences from the baseline values. Data evaluation was carried out by standard techniques (paired t -test) and a value of p < 0.05 was assumed to be significant.
  • Comments Comments (
    0
    ) |
How many outcome-specific endpoints are evaluated? 3
  • Comments Comments (
    0
    ) |
What is the (or one of the) endpoint(s) evaluated? (Each endpoint listed separately) Blood pressure (SBP and DBP)
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately). 2 Heart rate
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately).3 Cerebral bold flow (velocity of middle cerebral artery [VMCA])
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately).4
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately).5
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately).6
  • Comments Comments (
    0
    ) |
Clinical, physiological, other Physiological
  • Comments Comments (
    0
    ) |
What is the study design? Controlled Trial
  • Comments Comments (
    0
    ) |
Randomized or Non-Randomized? NCT
  • Comments Comments (
    0
    ) |
What were the diagnostics or methods used to measure the outcome? Objective
  • Comments Comments (
    0
    ) |
Optional: Name of Method or short description Velocities (time averaged maximum or Vmean) from both middle cerebral arteries were continuously monitored at a depth providing the best signal (50–55 mm) using TCD equipment (MultidopX, DWL, Sipplingen, Germany) and standard vessel identification criteria. Non-invasive blood pressure and heart rate were recorded with a pneumatic cuff (CBM-7000, ColinCorp., San Antonio, TX, USA).
  • Comments Comments (
    0
    ) |
Caffeine (general) Caffeine (general)
  • Comments Comments (
    0
    ) |
Coffee, Chocolate, energy drink, gum, medicine/supplement, soda, tea, other? Coffee
  • Comments Comments (
    0
    ) |
Measured or self reported? Measured
  • Comments Comments (
    0
    ) |
Children, adolescents, adults, or pregnant included? Adults
  • Comments Comments (
    0
    ) |
What was the reference, comparison, or control group(s)? (e.g. high vs low consumption, number of cups, etc.) Baseline measurements prior to coffee consumption
  • Comments Comments (
    0
    ) |
What were the listed confounders or modifying factors as stated by the authors? (e.g. multi-variable components of models.  Copy from methods) end-tidal CO2 concentration
  • Comments Comments (
    0
    ) |
What conflicts of interest were reported? No information provided
  • Comments Comments (
    0
    ) |
Refid 17346975
  • Comments Comments (
    0
    ) |
What were the sources of funding? This work was partially supported by the Grant Agency of the Ministry of Health of the Czech Republic: NR/8264-3.
  • Comments Comments (
    0
    ) |




Results & Comparisons

No Results found.