Original ContributionCardiovascular responses to energy drinks in a healthy population: The C-energy study☆,☆☆
Introduction
Energy drinks are beverages containing caffeine and other herbal supplements such as Panax ginseng, guarana, and other vitamin and minerals. Each manufacturer of these drinks has their own proprietary blend of additives; ingredients are listed on the label but volumes or percentages of each are not. These drinks are marketed as an aid to improve athletic performance, enhance concentration, and increase energy and weight loss [1], [2]. The first energy drink was introduced in the United States in 1997 [3] and by 2016, sales are expected to reach $52 billion [4]. Reported emergency department visits secondary to energy drinks skyrocketed from just over 1000 in 2005 to more than 20,000 in 2011 [4], [5]. Most often, these visits are due to a cardiac issue ranging from rapid heart rate, palpitations, myocardial infarction, stroke, and even cardiac arrest [6], [7], [8], [9], [10]. Recent studies have demonstrated that energy drink consumption may lead to altered platelet aggregation [11], [12] altered endothelial function [12] increased systolic blood pressure and prolonged QTc intervals [6], [13], [14], [15], suggesting a cardiovascular response that may lead to these pathologies.
Studies to date, have examined the electrocardiogram (ECG) at incremental periods of time post energy drink consumption. We hypothesized that ECG changes may occur at different time periods which could lead to cardiac pathologies and conditions after the consumption of an energy drink. Little is known about the possible mechanisms seen in patients who develop serious cardiovascular conditions associated with energy drink consumption. As a first step to better understand the cardiac response to energy drink consumption, we conducted the C-Energy study (Cardiovascular rEspoNses to EneRGy drinks in a healthy population) to determine if energy drinks alter: blood pressure, electrolytes (magnesium, potassium, calcium), activated bleeding time, and/or the ECG measured with 12-lead ECG Holter.
Section snippets
Methods
This was a prospective observational study to examine cardiovascular responses to energy drink consumption in healthy subjects 18–40 years old who were not energy drink naïve. Subjects were excluded if they were on any prescription medications, pregnant, or had known cardiovascular, hepatic, or endocrine diseases. Prior to recruitment, approval from the local institutional review board was obtained and patients provided written informed consent.
Patients were enrolled Monday–Friday in a research
Results
Fourteen subjects were recruited (mean age 28.6 years; range 15), and twelve (86%) were male. All subjects completed the protocol with no adverse events. Systolic blood pressures (baseline = 132, ± 7.83; PC = 151, ± 11.21; P = .001) (Table 1). QTc intervals (baseline = 423, ± 22.74; PC = 503, ± 24.56; P < .001) (Table 2); magnesium levels (baseline 2.04, ± 0.09; PC = 2.13, ± 0.15; P = .05); and calcium levels (baseline = 9.31, ± .28; PC = 9.52, ± .22; P = .018) significantly increased from baseline (Table 3). While
Discussion
Energy drinks contain added caffeine and other supplements that provide additional amounts of caffeine and other nervous system stimulating properties. Caffeine is a central nervous system stimulant routinely consumed as coffee or tea. When consumed in high doses, this chemical becomes toxic and can result in seizures and even death [16], [17], [18]. Besides added caffeine, another supplement added to many energy drinks is Panax ginseng purported to improve alertness and memory. Several studies
Conclusions
This study in healthy subjects demonstrates that energy drink consumption alters repolarization of the cardiac cycle possibly predisposing consumers to aLQTS, increased blood pressure, and electrolyte alterations. Because these physiological responses can lead to arrhythmias and other abnormal cardiac responses, it becomes important that emergency room personnel assess for energy drink toxicity and recognize these potential life-threatening consequences. Additional studies with larger samples
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Cited by (37)
Emerging risk factors for QT interval prolongation and torsades de pointes
2022, Torsades de PointesAcute effects of energy drink on hemodynamic and electrophysiologic parameters in habitual and non-habitual caffeine consumers
2021, Clinical Nutrition ESPENCitation Excerpt :Many studies investigate the effect of these beverages on human body which are not known exactly. For instance, Kozik et al. [6] reported that energy drinks caused an increase in systolic blood pressure (SBP), an alteration in electrolyte balances and hence repolarization anomalies, which could lead to arrhythmia and other abnormal cardiac events. Similarly, Shah et al. [7] reported a significant increase in SBP and a decrease in PR interval with respect to control after energy drink consumption, and Grasser et al. [8] showed increased heart rate (HR) following energy drink consumption.
Beware Energy Drinks: A Case of a Toxic Triad Syndrome in a Diabetic Patient With Nonalcoholic Fatty Liver Disease
2019, American Journal of the Medical SciencesRisk assessment of energy drinks with focus on cardiovascular parameters and energy drink consumption in Europe
2019, Food and Chemical ToxicologyCitation Excerpt :No robust conclusions can be drawn for higher acute intakes (more than 1 L ED), for children and adolescents and for chronic consumption, since there are no data available. ED consumption of 1 L resulted in significant prolongations of the QTc interval in three out of the four studies analyzing this endpoint in adults (Basrai et al., 2019; Kozik et al., 2016; Shah et al., 2016c), an effect which was not observed with moderate ED drinking. One study, which was conducted in the USA, observed enhanced QTc intervals in healthy young adults, which can be defined as serious (Kozik et al., 2016) and could therefore represent a potential health risk.
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Research activities were performed at Dignity Health-St. Joseph's Medical Center, Stockton CA
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This was a non-funded study. No authors have any conflicts of interest to report.