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Acute effects of coffee on QT interval in healthy subjects

Silvio Buscemi1, Alessandro Mattina, Maria Rosaria Tranchina

  • 1Department of Medicina Interna, Malattie Cardiovascolari e NefroUrologiche, Faculty of Medicine, University of Palermo, Italy. silbus@tin.it

Nutrition Journal
|February 4, 2011
PubMed

Insights

Caffeinated and decaffeinated coffee did not significantly alter the corrected QT interval, a measure of heart repolarization, in healthy adults. This suggests coffee consumption may not acutely impact left ventricular repolarization despite previous findings on endothelial function.

Area of Science:

  • Cardiology
  • Vascular Physiology
  • Pharmacology

Background:

  • Coronary endothelial function is crucial for diastolic ventricular relaxation and influences the electrocardiographic QT interval.
  • Flow-mediated dilation (FMD) in the brachial artery assesses endothelial function and predicts cardiovascular events.
  • Coffee's acute effects on FMD are debated, with some studies suggesting caffeinated coffee (CC) decreases FMD and decaffeinated coffee (DC) increases it.

Purpose of the Study:

  • To investigate the acute effects of CC and DC ingestion on the QT interval in healthy adults.
  • To determine if coffee consumption influences left ventricular repolarization.
  • To clarify the cardiovascular impact of coffee consumption.

Main Methods:

  • A randomized, double-blind, crossover study design was employed.
  • Participants included 19 males and 21 females.
  • The QT interval was measured in the hour following CC or DC ingestion.

Main Results:

  • Systolic and diastolic blood pressure were higher after CC ingestion.
  • Heart rate significantly increased 30 minutes after CC ingestion.
  • A significant increase in QT duration was observed one hour after DC ingestion, but not after CC. Corrected QT interval showed no significant changes after either coffee type.

Conclusions:

  • Neither CC nor DC appears to induce significant unfavorable acute changes in left ventricular repolarization in healthy individuals.
  • Despite influencing FMD, coffee's acute impact on the QT interval is not significant.
  • Further research is needed to understand coffee's effects in patients with cardiovascular diseases.

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