title: Cardiovascular responses to energy drinks in a healthy population: The C-energy study.
abstract: BACKGROUND
  Energy drink consumption has increased significantly over the past decade and is associated with greater than 20,000 emergency department visits per year. Most often these visits are due to cardiovascular complaints ranging from palpitations to cardiac arrest.
  
  
  OBJECTIVE
  To determine if energy drinks alter; blood pressure, electrolytes, activated bleeding time (ACT), and/or cardiac responses measured with a 12-lead electrocardiographic (ECG) Holter.
  
  
  METHODS
  Continuous ECG data was collected for five hours (30 minutes baseline and 4 hours post consumption [PC]). Subjects consumed 32 ounces of energy drink within one hour and data (vital signs and blood samples) was collected throughout the study period. Paired students t-test and a corresponding non-parametric test (Wilcoxon signed rank) were used for analysis of the data.
  
  
  RESULTS
  Fourteen healthy young subjects were recruited (mean age 28.6 years). Systolic blood pressure (baseline=132, ±7.83; PC=151, ±11.21; P=.001); QTc interval (baseline=423, ±22.74; PC=503, ±24.56; P<.001); magnesium level (baseline 2.04, ± 0.09; PC=2.13, ±0.15; P=.05); and calcium level (baseline=9.31, ±.28; PC=9.52, ±.22; P=.018) significantly increased from baseline. While potassium and ACT fluctuated (some subjects increased their levels while others decreased) these changes were not significant. Eight of the fourteen subjects (57%) developed a QTc >500 milliseconds PC. Other T-wave changes were noted in 9/14 (64.3%) subjects PC.
  
  
  CONCLUSIONS
  Energy drinks increased systolic blood pressure, altered electrolytes, and resulted in repolarization abnormalities. These physiological responses can lead to arrhythmias and other abnormal cardiac responses highlighting the importance that emergency room personnel assess for energy drink consumption and potential toxicity.
authors.affiliation: St. Joseph's Medical Center, Stockton CA -Clinical Research Department. Electronic address: teri.kozik@dignityhealth.org.
authors.forename: Teri M
authors.initials: TM
authors.lastname: Kozik
authors.affiliation: University of the Pacific, Stockton, CA.
authors.forename: Sachin
authors.initials: S
authors.lastname: Shah
authors.affiliation: Univeristy of the Pacific, Stockton, CA.
authors.forename: Mouchumi
authors.initials: M
authors.lastname: Bhattacharyya
authors.affiliation: St. Joseph's Medical Center, Stockton CA -Clinical Research Department.
authors.forename: Teresa T
authors.initials: TT
authors.lastname: Franklin
authors.affiliation: St. Joseph's Medical Center, Stockton CA -Clinical Research Department.
authors.forename: Therese Farrell
authors.initials: TF
authors.lastname: Connolly
authors.affiliation: St. Joseph's Medical Center - Director of Electrophysiology.
authors.forename: Walter
authors.initials: W
authors.lastname: Chien
authors.affiliation: St. Joseph's Medical Center - Director of Cardiology.
authors.forename: George S
authors.initials: GS
authors.lastname: Charos
authors.affiliation: University of California at San Francisco (UCSF), Department of Physiological Nursing.
authors.forename: Michele M
authors.initials: MM
authors.lastname: Pelter
mesh_terms: D000293:Adolescent; D000328:Adult; D001794:Blood Pressure / Q000502:physiology*; D015716:Electrocardiography, Ambulatory; D004573:Electrolytes / Q000097:blood; D061215:Energy Drinks / Q000009:adverse effects*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D004573:Electrolytes
keywords: Electrocardiography; Energy drink; Long QT syndrome; Repolarization; Supplements