Effects of Caffeine on Cerebral Blood Flow

Cardiovascular System Clinical Trial

Official title:

Effects of Caffeine on Cerebral Blood Flow in Clinically Healthy Young People

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05866848
• Other study ID #: CCBF
• Status: Completed
• Phase: N/A
• Start date: May 1, 2021
• Est. completion date: June 1, 2021

Study information

• Verified date: May 2023
• Source: Escola Superior de Tecnologia da Saúde de Coimbra
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The goal of this clinical trial is to evaluate in clinically healthy young people if:

• after caffeine ingestion, there are variations in blood velocity of the middle cerebral arteries (VMCA),

• this variation is dependent on the administered dose.

Transcranial Doppler ultrasonography was used to record blood VMCA in three groups of 15 clinically healthy young adults each - no caffeine, low caffeine (45 mg) and high caffeine group (120 mg). Transcranial Doppler ultrasonography provided simultaneous bilateral VMCA measurements while subjects performed functional tests (hyperventilation and hypoventilation orders) and three cognitive activities (Test 1, short-term remembering, Test 2, solving a vocabulary problem, and Test 3, solving a math problem) each in 31-second tests with 1-minute rest between them. Participants were assessed before and 30 minutes after caffeine ingestion.

Description:

Were used in the study, Capsules dosed with 45mg and 120 mg of anhydrous caffeine and flour capsules as a placebo. In the preparation of the capsules, a semi-automatic capsulator No. 0 (Capsunorm® by Tecnyfarma®) were used, colorless hard gelatin capsules No. 0 by Acopharma® and anhydrous caffeine (Biochem®, C.A.S. 58-08-2).

Viasys Sonara transcranial Doppler unit and a 2 MHz probe were used to sample the middle cerebral artery at depths of 60 millimeters, using emission doppler pulsed performing spectral analysis in real time. Two probes (bilaterally) of 2MHz were placed at a depth between 55 and 60 mm, thus making it possible to analyse both middle cerebral arteries simultaneously.

Each participant was asked not to ingest caffeine and exercise vigorously for at least 12 hours before the assessment. In the case of smokers, they were also asked not to smoke for at least 2 hours before the evaluation. The laboratory had medium luminosity, silent and controlled temperature (23º/24ºC). To avoid inter-observer errors, all examinations were performed by the same investigator who was not aware of what dose was/had been administered to the participant.

Subjects were tested while seated in a reclining chair located in a dimly lit, sound-attenuated room and performed the activities with their eyes closed.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 45
• Est. completion date: June 1, 2021
• Est. primary completion date: June 1, 2021
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 30 Years

Eligibility

Inclusion Criteria:

• clinically healthy young people

Exclusion Criteria:

• Individuals with hypertension, high cholesterol, diabetes, arrhythmias, carotid sinus syndrome, severe carotid stenosis and who were in an unstable clinical situation.

Related Conditions & MeSH terms

• Cardiovascular System

Intervention

Other:
• Placebo
Flour capsules as a placebo.
• Anhydrous caffeine (45mg)
Capsules dosed with 45mg of anhydrous caffeine.
• Anhydrous caffeine (120mg)
Capsules dosed with 120mg of anhydrous caffeine.

Locations

Country	Name	City	State
Portugal	Coimbra Health School	Coimbra

Sponsors (1)

Lead Sponsor	Collaborator
Escola Superior de Tecnologia da Saúde de Coimbra

Country where clinical trial is conducted

Portugal, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Changes in Mean Velocity (Basal)	Changes in Mean Velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Mean Velocity (Hypoventilation)	By performing Hypoventilation, changes in Mean Velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Mean Velocity (Hyperventilation)	By performing Hyperventilation, changes in Mean Velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Mean Velocity (Short-term memory test)	With short-term memory test, changes in Mean Velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Mean Velocity (Vocabulary problem)	With solving vocabulary problems, changes in Mean Velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Mean Velocity (Math problem.)	With solving math problems, changes in Mean Velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Peak systolic velocity (Basal)	Changes in Mean Velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Peak systolic velocity (Hypoventilation)	By performing Hypoventilation, changes in Peak systolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Peak systolic velocity (Hyperventilation)	By performing Hyperventilation, changes in Peak systolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Peak systolic velocity (Short-term memory test)	With short-term memory test, changes in Peak systolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Peak systolic velocity (Vocabulary problems)	With solving vocabulary problems, changes in Peak systolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Peak systolic velocity (Math problems)	With solving math problems, changes in Peak systolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Vend-diastolic velocity (Basal)	Changes in Mean Velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Vend-diastolic velocity (Hypoventilation)	By performing Hypoventilation, changes in Vend-diastolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Vend-diastolic velocity (Hyperventilation)	By performing Hyperventilation, changes in Vend-diastolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Vend-diastolic velocity (Short-term memory test)	With short-term memory test, changes in Vend-diastolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Vend-diastolic velocity (Vocabulary problems)	With solving vocabulary problems, changes in Vend-diastolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Primary	Changes in Vend-diastolic velocity (Math problems)	With solving math problems, changes in Vend-diastolic velocity, measure in m/s from baseline to 30 minutes after caffeine ingestion.	30 minutes
Secondary	Changes in Heart Rate (Basal)	Changes in Heart Rate, measure in bpm from baseline to 30 minutes after caffeine ingestion.	30 minutes
Secondary	Changes in Heart Rate (Hypoventilation)	By performing Hypoventilation, changes in Heart Rate, measure in bpm from baseline to 30 minutes after caffeine ingestion.	30 minutes
Secondary	Changes in Heart Rate (Hyperventilation)	By performing Hyperventilation, changes in Heart Rate, measure in bpm from baseline to 30 minutes after caffeine ingestion.	30 minutes
Secondary	Changes in Heart Rate (Short-term memory test)	With short-term memory test, changes in Heart Rate, measure in bpm from baseline to 30 minutes after caffeine ingestion.	30 minutes
Secondary	Changes in Heart Rate (Vocabulary problems)	With solving vocabulary problems, changes in Heart Rate, measure in bpm from baseline to 30 minutes after caffeine ingestion.	30 minutes
Secondary	Changes in Heart Rate (Math problems)	With solving math problems, changes in Heart Rate, measure in bpm from baseline to 30 minutes after caffeine ingestion.	30 minutes