Mixing alcohol and energy drinks: Acute subjective effects in a double-blinded randomized controlled trial

Abstract

Abstract Mixing alcohol and energy drinks: acute subjective effects in a double-blinded randomized controlled trial. Degree project in medicine Author: Mikis Tsagarakis Institute of Neuroscience and Physiology BACKGROUND The mix of alcohol and energy drinks has been linked to various mental and physical problems, such as underestimation of degree of alcohol intoxication, alcohol addiction, risk taking behavior and physical injury. Students report that they combine energy drink with alcohol to mask the sedating effects of alcohol. Complete understanding about the effects of the mix are still to be explained and one way to approach this question could be to investigate the acute subjective effects in a controlled environment. AIM We wanted to investigate whether we could find any details in the subjective effects that might provide a clue to some of the observed behavioral effects of alcohol mixed with energy drinks using the Biphasic alcohol effects scale (BAES) and the Profile of mood states (POMS), two instruments designed to measure different subjective states. MATERIALS AND METHODS This study was conducted as a double-blind randomized controlled trial. A total of 61 subjects were randomized to one of the following four treatments; 1. Placebo, 2. Energy drink, 3. Placebo + alcohol, 4. Energy drink + alcohol. To investigate the subjective effects of alcohol and energy drinks, we used BAES and POMS, two widely used questionnaires designed to measure different aspects of subjective mood states. Both questionnaires were completed three times each to look for any differences between the treatment groups; at baseline before consumption, at 20 minutes and at 60 minutes. 5 RESULTS A significantly higher score for alcohol compared to placebo was revealed on BAES ‘stimulation’ at 20 minutes and on POMS ‘confusion’ at 60 minutes. A significantly higher score for alcohol compared to placebo was revealed on BAES ‘sedation’ both at 20 and 60 minutes. No measurements were significant for energy drink alone. A higher score with a significant interaction effect between alcohol and energy drink was revealed for BAES ‘sedation’ at 60 minutes. DISCUSSION AND CONCLUSIONS As expected BAES was able to measure the stimulative and sedative effects of alcohol. POMS was only significant on ‘confusion’ and we conclude that POMS bring no additional information over BAES when measuring the acute effects of alcohol or energy drink. No measurements were significant for energy drink alone and under our experimental conditions it is questionable whether energy drink has any subjective effects at all. An interaction effect of the mix was revealed on BAES ‘sedation’ where subjects who received the mix reported higher score on this item. This result stand in contradiction to the reason why students drink the mix and we speculate that there is a discrepancy of how individuals report the mood-altering effects of the mix depending on when they report it. The result could explain how individuals underestimate the level of intoxication, which in turn might lead to an increased intake of alcohol and in the end a high-risk behavior. With this knowledge, it is important for people who consume alcohol in combination with energy drink to be aware of the plausible risk of the combination and that the effects are not certainly what the drinker often expects.