LAUSR

The European Cardiac Arrhythmia Society (ECAS) recently undertook an extensive and critical review of the literature of the cardiovascular events possibly associated with the growing use of energy drinks [1]. These products have been available in the USA since 1997 [2] for “Red Bull®” and 2002 for “Monster®.”. These two brands cover the preponderance of the US and worldwide markets. The other brands include “Rockstar®,” “Full Throttle®,” “Amp®,” and “Buffalo®” to name just a few of the commonly available products. The use of energy drinks is particularly popular among children and young adults ranging 18 to 34 years which is the age range that the manufacturers target [3]. The aggressive marketing campaigns and the sponsoring of various sports by manufacturers may explain the impressive growth of energy drinks, especially among young individuals. In Europe, energy drinks were first marketed in Germany in 1997 and in France in 2008. The growth of the US market has exceeded 240% between 2004 and 2009 [4]. In Italy, a survey in the years 2012 and 2013 showed that 22% of medical students declared that they were regular users of energy drinks [5]. Manufacturers claim that these non-alcoholic beverages have stimulating properties, improving physical performance and cognitive activities. The main ingredient of energy drinks is caffeine and its content varies within each brand. The average of 80 mg for Red Bull® is comparable to 1 espresso coffee whereas each can of Monster® contains 160 mg. Other varieties include “5-h shot” containing 200 mg of caffeine or even “10-h shot” with 420 mg of caffeine. This dose represents the maximum recommended daily dose for an adult and is excessive in children, adolescents, and young adults. Aside from caffeine, energy drinks may contain carbohydrates such as glucose; sucrose (although sugar free versions are available) vitamins B2, B8, B12; ginseng; yohimbine; kola-nut; guarana; and yerba mate. Notably, the latter two components also contain significant amounts of caffeine. A dose of 200-mg caffeine (3 mg/kg body weight for a 70-kg adult) achieves a maximum plasma concentration 30–60 min after administration. Caffeine is metabolized by the liver into xanthines, has a half-life ranging from 2 to 12 h, and is excreted through the kidney. Large interindividual variability in the absorption and metabolism of caffeine has been reported. While caffeine doses above 400 mg are known to be a possible cause of cardiovascular complications in adults, there is no agreed-upon safe dose, in children. Adolescents and young adults consume more than one can of energy drinks over a short time period not infrequently combined with alcohol. Consumption of high-dose caffeine may be associated with habituation and withdrawal symptoms that include anxiety, psychosis, and alteration of sleep pattern. An increased risk of addiction to other drugs by use of energy drink has also been reported. [6] In our review, we found 8 cases of out-of-hospital cardiac arrest in which energy drinks were strongly implicated as a possible cause (Table 1). Of these, two were fatal [7] (cases 2 and 5). A 25-year-old woman with mitral valve prolapse developed intractable ventricular fibrillation after consumption of a drink of a guarana and ginseng beverage rich in caffeine [8]. The patient died despite resuscitative efforts. A 28-year-old man was admitted to emergency room with ventricular tachycardia which was terminated by cardioversion. The patient died on hospital day 3. The patient consumed 3 cans of 250-mL energy drink 5 h before a basketball match [7]. Another case of cardiac arrest occurred in a 28-year-old motocross rider (case 3, Table 1) with ventricular fibrillation that was successfully terminated. This occurred after he consumed 7–8 cans of caffeinated energy drinks prior to his collapse [9]. He had the clinical and biological signs of associated acute myocardial infarction. The coronary * Samuel Lévy [email protected]