Cardiovascular Effects of Energy Drinks in Familial Long QT Syndrome: A Randomized Cross-Over Study

Belinda Gray; Jodie Ingles; Caroline Medi; Timothy Driscoll; Christopher Semsarian

doi:10.1016/j.ijcard.2016.12.019

Cardiovascular Effects of Energy Drinks in Familial Long QT Syndrome: A Randomized Cross-Over Study

Int J Cardiol. 2017 Mar 15:231:150-154. doi: 10.1016/j.ijcard.2016.12.019.

Authors

Belinda Gray¹, Jodie Ingles², Caroline Medi³, Timothy Driscoll⁴, Christopher Semsarian⁵

Affiliations

¹ Department of Cardiology, Royal Prince Alfred Hospital, NSW, Australia; Sydney Medical School, University of Sydney, NSW, Australia; Agnes Ginges Centre for Molecular Cardiology, Centenary Institute, NSW, Australia. Electronic address: b.gray@centenary.org.au.
² Department of Cardiology, Royal Prince Alfred Hospital, NSW, Australia; Sydney Medical School, University of Sydney, NSW, Australia; Agnes Ginges Centre for Molecular Cardiology, Centenary Institute, NSW, Australia. Electronic address: j.ingles@centenary.org.au.
³ Department of Cardiology, Royal Prince Alfred Hospital, NSW, Australia; Sydney Medical School, University of Sydney, NSW, Australia; Agnes Ginges Centre for Molecular Cardiology, Centenary Institute, NSW, Australia. Electronic address: c.medi@centenary.org.au.
⁴ School of Public Health, University of Sydney, NSW, Australia. Electronic address: tim.driscoll@sydney.edu.au.
⁵ Department of Cardiology, Royal Prince Alfred Hospital, NSW, Australia; Sydney Medical School, University of Sydney, NSW, Australia; Agnes Ginges Centre for Molecular Cardiology, Centenary Institute, NSW, Australia. Electronic address: c.semsarian@centenary.org.au.

PMID: 28189188
DOI: 10.1016/j.ijcard.2016.12.019

Abstract

Background: Caffeinated energy drinks may trigger serious cardiac effects. The aim of this study was to determine the cardiovascular effects of caffeinated energy drink consumption in patients with familial long QT syndrome (LQTS).

Methods and results: From 2014-2016, 24 LQTS patients aged 16-50 years were recruited to a randomized, double-blind, cross-over study of energy drink (ED) versus control (CD) with participants acting as their own controls (one week washout). The primary study outcome was an increase in corrected QT interval (QTc) by >20ms. Secondary outcomes were changes in systolic and diastolic blood pressure. In 24 patients with LQTS (no dropout), mean age was 29±9 years, 13/24 (54%) were female, and 8/24 (33%) were probands. Intention to treat analysis revealed no significant change in QTc with ED compared with CD (12±28ms vs 16±27ms, 3% vs 4%, p=0.71). The systolic and diastolic blood pressure significantly increased with ED compared to CD (peak change 7±16mmHg vs 1±16mmHg, 6% vs 0.8%, p=0.046 and 8±10 vs 2±9mmHg, 11% vs 3% p=0.01 respectively). These changes correlated with significant increases in serum caffeine (14.6±11.3 vs 0.5±0.1μmol/L, p<0.001) and serum taurine (737±199 vs -59±22μmol/L, p<0.001). There were three patients with dangerous QTc prolongation of ≥50ms following energy drink consumption.

Conclusion: Caffeinated energy drinks have significant haemodynamic effects in patients with LQTS, especifically an acute increase in blood pressure. Since dangerous QTc prolongation was seen in some LQTS patients, we recommend caution in young patients with LQTS consuming energy drinks.

Keywords: Long QT syndrome; energy drinks.

Publication types

Randomized Controlled Trial

MeSH terms

Adolescent
Adult
Blood Pressure / drug effects*
Caffeine / blood
Cross-Over Studies
Diastole / drug effects
Double-Blind Method
Electrocardiography*
Energy Drinks / adverse effects*
Female
Heart Conduction System / drug effects*
Heart Conduction System / physiopathology
Heart Rate / drug effects*
Humans
Long QT Syndrome / blood
Long QT Syndrome / physiopathology*
Male
Middle Aged
Risk Factors
Systole / drug effects
Taurine / blood
Young Adult

Substances

Taurine
Caffeine