to explore the effect of sodium intake on the coffee-induced increase in blood pressure
ID
Source
Brief title
Condition
- Vascular hypertensive disorders
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
response to coffee intake of blood pressure Dinamap and Nexfin) and cardiac
output (Pulse contour method applied to continuous blood pressure signal that
is measured at the finger using Nexfin)
Secondary outcome
sodium and creatinine excretion in urine; plasma caffeine concentration before
and 2 hours after intake of 2 cups of coffee
Background summary
Caffeine intake increases blood pressure acutely, an effect that deminishes
over time when coffee is used regularly. This effect is likely to be caused by
antagonism of the vasodilator action of endogenous adenosine. Recently, high
sosium intake has been shown to augment the vasodilator action of adenosine in
animals. We hypothesize that high sodium intake also augments the blod pressure
response to caffeine. If true, the current epidemiological data base on the
cardiovascular safety of caffeine consumption needs to readressed taking into
account the modifying role of sodium intake.
Study objective
to explore the effect of sodium intake on the coffee-induced increase in blood
pressure
Study design
Non-blinded randomized cross-over design.
Intervention
All volunteers will use a high (6 gram/24 hours) and low (12 gram/24 hours)
sodium chloride diet (in random order; 5 days on each diet, both periods
separated by at least 4 days). At the end of each period, 24 hour urine is
collected to assess sodium excretion. Volunteers will abstain from caffeine
containing beverages, alcohol and nicotine for at least 24 hours. The blood
pressure response to two cups of caffeine containting coffee, prepared
according to standardized procedures, will be measured. Venous blood is sampled
before and two hours after coffee administration to measure caffeine
concentration.
Study burden and risks
No relevant risk is anticipated
Postbus 9101
6500 HB Nijmegen
NL
Postbus 9101
6500 HB Nijmegen
NL
Listed location countries
Age
Inclusion criteria
Signed informed consent.
At least 18 years of age.
Exclusion criteria
Use of any medication or recreational drugs (exept oral anticonception in female participants)
Hypertension (defined as SBP > 140 mmHg and/or DBP > 90 mmHg as measured after at least 5 minutes in supine position by standard auscultatory measurements)
Difference in blood pressure between the two arms of 10 mmHg or more (systolic)
Alcohol consumption > 2 units/day
Any cardiovascular abnormality as detected during routine history and physical examination.
BMI > 25
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL39999.091.12 |