Desire to Drink Alcohol is Enhanced with High Caffeine Energy Drink Mixers

Alcohol Versus Combined Alcohol and Energy Drinks Consumption: risk behaviours and consumption patterns among European students

INTRODUCTION

Recent research found that mixing energy drinks with alcohol (AmED) could be more risky than drinking alcohol alone. Our aim was to compare rates of risk behaviours in consumers AmED versus exclusive alcohol drinkers, matching them based on their drinking frequency.

METHODS

Data about sixteen-year-old students who reported the number occasions on which they had drunk AmED or alcohol only in the preceding 12 months (n = 32,848) were drawn from the 2019 ESPAD study. After matching for consumption frequency, the sample consisted of 22,370 students (11,185 AmED consumers and 11,185 exclusive alcohol drinkers). Key predictors comprised substance use, other individual risk behaviours and family characteristics (parental regulation, monitoring and caring).

RESULTS

The multivariate analysis showed significantly higher odds of being AmED consumers compared to exclusive alcohol drinkers in the majority of the investigated risk behaviours, including: daily tobacco smoking, illicit drug use, heavy episodic drinking, truancy at school, engaging in physical fights and serious arguments, having troubles with the police and having unprotected sexual intercourse. Instead, lower odds were found for reporting high parents' educational level, medium and low family economic status, perceived possibility to freely talk about problems to family members, spending free time reading books or other hobbies.

CONCLUSIONS

Our study shows that, given the same consumption frequency in the past year, AmED consumers typically reported higher associations with risk-taking behaviours compared to exclusive alcohol drinkers. These findings advance past research that failed to control for the frequency of AmED use versus exclusive alcohol consumption.

Caffeine consumption and onset of alcohol use among early adolescents

Preventing or delaying the onset of alcohol use among children and youth is an important public health goal. One possible factor in alcohol use onset among early adolescents is caffeine. The aim of this study was to assess the possible contribution of caffeine to the onset of alcohol use during early adolescence. We used data from the Young Mountaineer Health Study Cohort. Survey data were collected from 1349 (response rate: 80.7%) 6th grade students (mean age at baseline 11.5 years) in 20 middle schools in West Virginia during the fall of 2020, and again approximately 6 months later in spring of 2021. We limited our analyses to students reporting never having used any form of alcohol at baseline. Logistic regression was employed in multivariable analyses and both Odds Ratios and Relative Risks reported. At follow-up, almost 14% of participants reported having consumed alcohol at least once and 57% used caffeine of 100 mg + daily. In multivariable analyses we controlled for social and behavioral variables known to impact tobacco use. Caffeine use was operationalized as a three-level factor: no use, <100 mg per day, and 100 + mg per day, with the latter being the approximate equivalent of the minimum of a typical cup of coffee or can of energy drink. Caffeine use of 100 mg + per day was significantly related to alcohol use at 6-months follow-up (OR: 1.79, RR: 1.56, p = .037). We conclude that caffeine consumption among 11-12-year-old adolescents may be a factor in early onset of alcohol use.

Effect of simultaneous coffee/caffeine and ethanol administration on sperm quality and reproductive hormones: an experimental study in Sprague Dawley rats

Chronic alcohol or coffee/caffeine consumption has been associated with negative effects on male reproductive system. The present study evaluated the possible interaction (combination treatment) of coffee/caffeine and alcohol and its resultant consequence on sperm parameters in rats. Ten groups of adult Sprague Dawley rats (n = 5 per group) were orally gavaged with different quantities of coffee (≈5, 10, and 20 mg/kg caffeine); 30% v/v ethanol (0.5, 1, and 2 g/kg); coffee + ethanol or vehicle (distilled water) daily for 60 days. Sperm parameters, serum sex hormone levels, together with antioxidants and lipid peroxidation status of testis homogenate were evaluated. Single and combined administration of coffee/caffeine and ethanol caused a reduction in sperm count dose-dependently (p = 0.0002), but this effect was highest in the combined treatment. Sperm viability, motility, and morphology were unaffected by coffee or ethanol administration, but the combination produced detrimental effects on them. While changes in follicle stimulating hormone were not significant, testosterone and luteinizing hormone levels were decreased significantly and dose-dependently in all experimental groups (p < 0.05-0.0001). This effect was most pronounced in the groups that received the combination. Testicular superoxide dismutase and catalase activities, and reduced glutathione and malondiadehye (MDA) levels were not affected by coffee/caffeine, but ethanol decreased (p < 0.05) the antioxidants and elevated MDA levels mostly at 2 g/kg. The combination reduced (p < 0.0001) the antioxidants and increased MDA levels in testis homogenates at all doses. Combination of coffee/caffeine and ethanol potentiates their detrimental effects on sperm quality and reproductive hormones via reduction in testicular antioxidants activities and elevation of lipid peroxidation in rats.

Effects of Caffeine and Caffeinated Beverages in Children, Adolescents and Young Adults: Short Review

The prevalence of ED consumption has increased over the past 10–15 years. Studies describing the effects of caffeine and caffeinated beverages show confusing results, so it seems important to regularly summarize the available facts, and in more detail. By a thorough analysis of more than 156 scientific papers, the authors describe the molecular background of absorption, as well as the positive and negative effects of different dosages of caffeine, just like its effects in physical activity and performance. ED and EDwA consumption is a regular habit of not only adults, but nowadays even of children and adolescents. There are no safe dosages described of caffeine or ED consumption for children. There are no positive short- or long-term effects of these compounds/products concerning developing brain functions, psycho-motor functions, or social development. Instead, there are many unpleasant side effects, and symptoms of regular or higher-dose ED consumption, especially at younger ages. This mini review describes many details of these unpleasant side effects, their severity, and motivations for consuming these compounds/products. In a quantitative research in Hungary (10–26 years, mean age: 15.6 ± 3.8 y, 1459 subjects, randomly chosen population), a survey based on a questionnaire asking people about their ED consumption habits was conducted. According to the data, 81.8% of the participants consumed EDs at least once, and 63.3% tried several products of the kind. A positive correlation was found between age and consumption (p < 0.001). The results show that a high proportion of this group often consumed EDwA, in many cases leading to harmful side-effects of caffeine overdose. In a sample of Hungarian high school and college students (17–26 years), ED consumption matched the international data, and only 19.7% of respondents did not use EDs at all (had never tasted an ED in their life).

Short-term consumption of alcohol (vodka) mixed with energy drink (AMED) attenuated alcohol-induced cerebral capillary disturbances and neuroinflammation in adult wild-type mice

Background: The ingestion of combinatory Alcohol Mixed with Energy Drink (AMED) beverages continues to increase markedly, particularly among young adults. Some studies suggest detrimental health effects related to the combination of alcohol with energy drink formulations; however, the consumption of AMED has not been investigated in context of the cerebral microvasculature or neuroinflammation. We hypothesized that cerebral capillary integrity and glial cells are particularly vulnerable to the combination of AMED.Methods:12-week old wild-type C57BL/6J mice were orally gavaged with either vehicle (water), alcohol (vodka), an energy drink (Mother^TM), or a combination AMED, daily for five days. Thereafter, mice were sacrificed, blood alcohol concentrations were analysed and cryosections of brain specimens were subjected to confocal immunofluorescent analysis for measures of cerebral capillary integrity via immunoglobulin G (IgG), and markers of neuroinflammation, ionized-calcium-binding-adaptor-molecule 1 (Iba1) and Glial-Fibrillary-Acidic-Protein (GFAP). Proinflammatory cytokines, IL-2, IL-17A, IFN-ϒ, and anti-inflammatory cytokines, IL-4, IL-6 and IL-10, were also measured in serum.Results: Consistent with previous studies, cerebral capillary dysfunction and astroglial cell activation were markedly greater in the alcohol-only group (AO); however, the AO-induced effects were profoundly attenuated with the AMED combination. Mice maintained on AO and AMED interventions exhibited a moderate increase in microglial recruitment. There were no significant changes in pro-inflammatory nor anti-inflammatory cytokines in ED or AMED treated mice.Conclusion: This study suggests that paradoxically the acute detrimental effects of alcohol on cerebral capillary integrity and astrogliosis are counteracted with the co-provision of an ED, rich in caffeine and taurine and containing B-group vitamins.

Caffeine increases alcohol self-administration, an effect that is independent of dopamine D2 receptor function

The rising popularity of alcohol mixed with energy drinks (AmEDs) has become a significant public health concern, with AmED users reporting higher levels of alcohol intake than non-AmED users. One mechanism proposed to explain this heightened level of alcohol intake in AmED users is that the high levels of caffeine found in energy drinks may increase the positive reinforcing properties of alcohol, an effect that may be dependent on interactions between adenosine receptor signaling pathways and the dopamine D₂ receptor. Therefore, the purpose of the current study was to confirm whether caffeine does increase the positive reinforcing effects of alcohol using both fixed ratio (FR) and progressive ratio (PR) designs, and to investigate a potential role of the dopamine D₂ receptor to caffeine-induced increases in alcohol self-administration. Male Long-Evans rats were trained to self-administer a sweetened alcohol solution (10% v/v alcohol + 2% w/v sucrose) on an FR2 schedule of reinforcement, and the effects of caffeine (0, 5, 10, and 20 mg/kg, i. p. [intraperitoneally]) on the maintenance of alcohol self-administration and alcohol break point were examined. Parallel experiments in rats trained to self-administer sucrose (0.8% w/v) were conducted to determine whether caffeine's reinforcement-enhancing effects extended to a non-drug reinforcer. Caffeine pretreatment (5-10 mg/kg) significantly increased sweetened alcohol self-administration and motivation for a sweetened alcohol reinforcer. However, similar increases in self-administration of a non-drug reinforcer were not observed. Contrary to our hypothesis, the D₂ receptor antagonist eticlopride did not block a caffeine-induced increase in sweetened alcohol self-administration, nor did it alter caffeine-induced increases in motivation for a sweetened alcohol reinforcer. Taken together, these results support the hypothesis that caffeine increases the positive reinforcing effects of alcohol, which may explain caffeine-induced increases in alcohol intake. However, the reinforcement-enhancing effects of caffeine appear to be independent of D₂ receptor function.

Gender differences in driving control of young alcohol-impaired drivers

BACKGROUND

Male and female drivers exhibit different degrees of vehicle control while driving under the influence of alcohol. However, this interaction between alcohol and gender is understudied. The present study examined the effects of different alcohol levels on the driving control of male and female drivers with the help of driving simulator experiments in heterogeneous traffic conditions.

METHOD

Forty young drivers (20 males and 20 females) completed simulated driving at four Blood Alcohol Concentration (BAC) levels: 0% (control), 0.03%, 0.05% and 0.08%. Driving impairment in vehicle control was measured in terms of average speed, acceleration variability and reaction time of drivers. Repeated-measures ANOVA tests were conducted and regression models were developed for male and female drivers to quantify the effects of BAC levels and driver characteristics on the driving control measures.

RESULTS

Significant effects of gender were observed for average speed (p <  0.001) and acceleration variability (p = 0.015) but not for reaction time of drivers (p =  0.891). Further, the effect of BAC was significant in all the three measures of vehicle control (p <  0.001). Driving control improved with increasing age of male drivers while caffeine consumption was observed as an alcohol-antagonizing factor in female drivers.

CONCLUSION

The findings suggest that vehicle control of female drivers is more likely to get affected even at low BAC levels, providing evidence that they belong to critical section of driving community in terms of alcohol-related impairment. The findings may help in discouraging drinking and driving among male and female drivers.

Supplemental taurine during adolescence and early adulthood has sex-specific effects on cognition, behavior and neurotransmitter levels in C57BL/6J mice dependent on exposure window

The mammalian brain goes through final maturation during late adolescence and early adulthood with sex differences in timing. The key cellular processes, including changes in neurotransmitter receptor density and synaptic pruning, make this age uniquely vulnerable to neurotoxic insults. Teenagers and young adults are the major consumers of energy drinks, which contain high levels of taurine and caffeine. Taurine is one of the most abundant amino acids in the central nervous system, but the effects of supplemental taurine consumption during adolescence has not been well studied. We conducted an initial short-term exposure study with 0.12% taurine in drinking water and a long-term exposure dose-response study using 0.06 and 0.12% taurine in male and female C57BL/6J mice. We examined a broad range of cognitive functions and behaviors and measured neurotransmitter levels. We found no significant differences in anxiety, open field locomotor activity, or sensorimotor gating. However, we found impairments in novel object recognition and sex differences in Morris water maze. When taurine treatment stopped before behavioral experiments began, male mice had significant impairments in spatial learning and memory. In the dose-response study when taurine treatment continued throughout behavioral experiments, females had significant impairments. We also found sex differences in neurotransmitter levels with females having higher levels of glutamate, DOPAC and 5-HIAA. We conclude that both females and males are at risk from excess taurine consumption during final brain maturation.

Use of Alcohol Mixed with Energy Drinks Increases the Prevalence of Driving Violations among Brazilian Truck Drivers

Background: The use of alcohol mixed with energy drinks (AmED) has been reported to be associated with a variety of unsafe driving practices. Truck drivers are vulnerable to driving violations, particularly because of their engagement in drug use. The use of AmED among these professionals remains unknown. Aim: To estimate the prevalence of AmED use and its association with driving violations among truck drivers. Methods: 684 drivers were recruited in Sao Paulo, Brazil. The use of drugs was reported. Drivers were split into three groups: (a) alcohol abstainers (AA); (b) alcohol-only users (AO); and (c) users of AmED. Intergroup comparisons were performed by polynomial logistic regression (the reference category was AO). We also performed Poisson regression analysis to obtain the prevalence ratio; the significance level was stipulated at 5%. Results: The prevalence of drivers reporting the use of AmED was 16.8%. Users of AmED (a) were younger, (b) were less experienced drivers, (c) had a heavier pattern of alcohol use, (d) used illicit drugs more frequently, and (e) had poorer sleep quality than AO subjects. A higher prevalence of drivers who had arguments or fights while driving (PR = 1.71) and of drivers who drove unbelted (PR = 1.66) ingested AmED than of AO subjects. Conclusions/importance: The use of AmED increased the prevalence of driving violations beyond the risks commonly attributed to alcohol use. We suggest additional investments in preventative measures based on the beverage category and a revision of the work organization of truck drivers to reduce their health and social risks.

Rewarding and aversive doses of caffeine alter activity but not conditioned place preference induced by ethanol in DBA/2J mice

Increases in the consumption of ethanol and caffeine have been attributed to increased subjective feelings of intoxication and pleasure from the combination. Previous studies have shown that caffeine can be rewarding at low doses and aversive at high doses, although these findings are at times inconsistent between studies using comparable doses. Similarly, studies investigating the rewarding effects of ethanol and caffeine combinations have yielded mixed results. To address this issue, the present experiments were designed to investigate the rewarding effects of caffeine, as well as of caffeine + ethanol combinations. Male DBA/2J mice were exposed to an unbiased conditioned place preference (CPP) procedure with various doses of caffeine (1, 3, 10, 30 mg/kg) and ethanol (1, 2 g/kg), as well as various conditioning trial durations (5, 30, 60 min). Caffeine dose-dependently increased locomotor activity during conditioning, and produced a biphasic effect on place conditioning. Specifically, a low dose of caffeine (3 mg/kg) produced place preference, while a high dose (30 mg/kg) produced place aversion. When combined with alcohol, caffeine dose-dependently increased ethanol's stimulatory effect. However, the addition of caffeine had no effect on ethanol place preference, as there were no differences in the strength of place preference between mice conditioned with ethanol alone, and mice conditioned with any combination of ethanol and caffeine. These studies add evidence for caffeine's biphasic effects while also emphasizing the importance of considering temporal and methodological parameters when using Pavlovian conditioning procedures to study drug combinations.

The association between caffeinated alcoholic beverages and the perpetration of intimate partner violence

Background: Problematic alcohol use is a recognized risk factor for intimate partner violence (IPV) perpetration.Objective: The use of caffeinated alcoholic beverages (CAB) appears to be associated with high-risk drinking behavior but the relationship between CAB use and IPV has yet to be explored.Methods: Sixty male and 40 female married or dating participants responded to an online survey including measures of past-year alcohol use and partner violence.Results: Logistic regression analyses revealed that CAB users were significantly more likely to perpetrate physical assault and partner injury after controlling for age, sex, ethnicity, income, and heavy alcohol use. The relationship between CAB use and perpetration of sexual coercion was better accounted for by heavy alcohol use.Conclusion: Results from the current study suggest that there exists an independent link between CAB use and partner violence perpetration.

Alcohol Mixed with Energy Drinks (AmED) and Negative Alcohol-Related Consequences among South Korean College Students

Consumption of alcohol mixed with energy drinks (AmED) has been associated with various alcohol-related consequences among college students. However, more information is required to assess how this relationship is affected by sociodemographic and environmental factors. This paper investigates the association between AmED consumption and negative alcohol-related consequences while (1) stratifying AmED users by sex, (2) examining a range of outcomes specific to the college context (e.g., missing class), and (3) controlling for drinking frequency and amount. We surveyed and analyzed the data of 4592 students in a nationally representative sample of 82 colleges in South Korea. Multiple linear regression analysis was used to identify the association between AmED use and a number of alcohol-related consequences (ranging from a score of 0–12) while adjusting for covariates, including drinking frequency and intake per drinking session. Of our study population, 22.0% of alcohol-consuming men and 13.4% of alcohol-consuming women reported AmED consumption in the past 12 months. AmED users experienced a greater number of alcohol-related consequences (e.g., missing class, engaging in unplanned sexual activity) than non-AmED users (men β: 0.804, p ≤ 0.0001; women β: 0.522, p ≤ 0.0001). Male AmED users consuming alcohol once a month (β: 1.155, p ≤ 0.0001) and female users consuming less than once a month (β: 1.019, p ≤ 0.0001) experienced the greatest number of consequences compared to non-users, as did AmED users consuming 3–4 drinks per drinking session (men β: 1.012, p ≤ 0.0001; women β: 0.993, p ≤ 0.0001). Our findings reveal that both male and female college students who consume AmED experience a greater number of negative alcohol-related consequences than those who do not. Rather than high-risk drinkers, moderate drinkers who consume alcohol infrequently and/or in low amounts may experience more consequences when consumers of AmED.

Intensity of Energy Drink Use Plus Alcohol Predict Risky Health Behaviours among University Students in the Caribbean

The relationship between energy drink (ED) use and risky behaviours has not been explored in the Caribbean, where youth risky behaviours are prevalent. This paper examines the relationship between ED use and risky behaviours and the moderating effect of gender among 1994 undergraduate students in Trinidad and Tobago. Analyses examined the association between ED use and risky behaviours, and the significant predictors of risky behaviours. Analysis of variance determined whether there were differences in risky behaviours between those who used only alcohol or EDs, both alcohol and EDs, alcohol mixed with EDs and neither alcohol nor EDs; and the difference between those with high and low intensity of ED use. In both males and females current use of energy drinks was positively associated with harmful substance use, risky sexual behaviours, and risky non-sexual behaviours, more strongly for males. The strongest predictor of risky behaviours was gender. Males consuming both alcohol and EDs, independently or mixed, were most likely to have risky behaviours. Consistent with previous reports, harmful alcohol use and other risk taking health behaviours appear to be predicted by a combination of high intensity use of EDs and alcohol. In countries like Trinidad and Tobago where violence, alcohol use disorders, STI/HIV infection and teenaged pregnancy are prevalent, the assessment of consumption of EDs and alcohol may be an important potential predictor of health compromising behaviours.

Alcohol mixed with energy drink use during young adulthood

AIMS

Alcohol mixed with energy drink (AmED) use is associated with negative consequences including hazardous alcohol use and driving under the influence. While many studies have focused on correlates of AmED use among college samples, very few have examined patterns of AmED use during adolescence and young adulthood within the general population. Accordingly, the purpose of this study is to assess age differences in AmED use among a national sample of respondents aged 18 to 30.

METHODS

The data for this study come from the Monitoring the Future panel study from 2012 to 2015. The sample consists of 2222 respondents between the ages of 18 and 30. Multiple logistic regression using generalized estimating equations (GEE) was used to model past-year AmED prevalence across age and other covariates.

RESULTS

Nearly half (45.0%) of respondents indicated past-year AmED use at some point during the study period. The lowest prevalence rates were found at age 18 (25.9%) and the highest prevalence rates at age 21/22 (43.5%). GEE analyses indicated a statistically significant positive linear and negative quadratic trend with respect to the association between age of respondent and past-year AmED use. Namely, peak use occurred in early young adulthood (age 21/22 and 23/24) and then declined, reaching 32.0% by age 29/30. College attendance and several substance use behaviors at age 18 moderated these linear and quadratic age trends.

CONCLUSIONS

AmED use peaked rapidly in early young adulthood and declined into later young adulthood. Substance use during adolescence was associated with a higher incidence of AmED use across all young adult ages and a slower decline of AmED use after age 21/22. Several sociodemographic factors were associated with AmED use, particularly college attendance at the age of 21/22.

Differential development of acute tolerance may explain heightened rates of impaired driving after consumption of alcohol mixed with energy drinks versus alcohol alone

Consumers of alcohol mixed with energy drinks (AmED) are more likely to drive while impaired when compared to alcohol alone consumers. In addition, acute tolerance to the internal cues of feelings of intoxication is known to contribute to maladaptive decisions to drive while impaired. Therefore, the purpose of this study was to determine whether there is differential development of acute tolerance for AmED versus alcohol alone for ratings of willingness to drive after alcohol consumption. Social drinkers (n = 12) attended 4 separate sessions where they received alcohol and energy drinks, alone and in combination. The development of acute tolerance to alcohol was assessed for several objective (a computerized cued go/no-go reaction time task) and subjective measures at matched breath alcohol concentrations (BrACs) for the ascending and descending limbs of the BrAC curve. The results indicated that alcohol administration decreased willingness to drive ratings. Acute tolerance was observed in the AmED dose condition for only the willingness to drive ratings that were significantly higher on the descending versus ascending test. Alcohol-induced impairments of the computer task performance did not exhibit any acute tolerance. Therefore, the differential development of acute tolerance may explain why many studies observe higher rates of impaired driving for AmED consumers compared to alcohol alone consumers. Because drunk driving is a major public health concern, alcohol consumers should be warned that the use of energy drink mixers with alcohol could lead to a false sense of security in one's ability to drive after drinking. (PsycINFO Database Record

Alcohol mixed with energy drink (AMED): A critical review and meta-analysis

The purpose of this systematic review and meta-analysis was to critically review the (1) prevalence of alcohol mixed with energy drink (AMED) consumption, (2) motives for AMED consumption, (3) correlates of AMED consumption, and (4) whether AMED consumption has an impact on (a) alcohol consumption, (b) subjective intoxication, and (c) risk-taking behavior. Overall a minority of the population consumes AMED, typically infrequently. Motives for AMED consumption are predominantly hedonistic and social. Meta-analyses revealed that AMED consumers drink significantly more alcohol than alcohol-only (AO) consumers. Within-subject comparisons restricted to AMED consumers revealed that alcohol consumption does not significantly differ between typical AMED and AO occasions. On past month heaviest drinking occasions, AMED users consume significantly less alcohol on AMED occasions when compared to AO occasions. AMED consumers experience significantly fewer negative consequences and risk-taking behavior on AMED occasions compared with AO occasions. Meta-analyses of subjective intoxication studies suggest that AMED consumption does not differentially affect subjective intoxication when compared to AO consumption. In conclusion, when compared to AO consumption, mixing alcohol with energy drink does not affect subjective intoxication and seems unlikely to increase total alcohol consumption, associated risk-taking behavior, nor other negative alcohol-related consequences. Further research may be necessary to fully reveal the effects of AMED.

Behavioral effects of the combined use of alcohol and energy drinks on alcohol hangover in an experimental mice model

In last few years it has been a significant increase in the consumption of alcohol combined with energy drink. The aim of this work was to study the effect of this mixture in motor and affective behaviors during an alcohol hangover episode. Male Swiss mice received one of the following treatments: saline + sucrose; saline + energy drink; ethanol + sucrose; ethanol + energy drink. Ethanol dose was 3.8 g/kg BW (i.p.) and energy drink dose was 18 ml/kg BW (gavage) at ZT1 (8 am) (ZT: Zeitgeber time; ZT0: 7 am; lights on). The behavioral tests used were tight rope test to determine motor coordination; hanging wire test to study muscular strength; elevated plus maze and open field tests to evaluate anxiety like-behavior and locomotor activity. Tests were carried out at basal point that matched with lights onset and every 6 h up to 18 h after treatments. Hangover onset was established at ZT7 when blood alcohol concentration (BAC) was almost zero. Our results showed that the mixture of alcohol and energy drink altered significantly motor skills. Specifically, a significant decrease was observed in the performance of the animals in the tightrope and hanging wire tests in groups treated with the mixture of alcohol and energy drink. A significant impairment in the anxiety-like behavior was observed mainly at the beginning of alcohol hangover. These findings suggest that energy drink added to alcohol extends motor disabilities observed during an alcohol hangover episode in comparison with animals that received alcohol alone.

Taurine, caffeine, and energy drinks: Reviewing the risks to the adolescent brain

Energy drinks are emerging as a major component of the beverage market with sales projected to top $60 billion globally in the next five years. Energy drinks contain a variety of ingredients, but many of the top-selling brands include high doses of caffeine and the amino acid taurine. Energy drink consumption by children has raised concerns, due to potential caffeine toxicity. An additional risk has been noted among college-aged consumers of energy drinks who appear at higher risk of over-consumption of alcohol when the two drinks are consumed together. The differential and combinatorial effects of caffeine and taurine on the developing brain are reviewed here with an emphasis on the adolescent brain, which is still maturing. Key data from animal studies are summarized to highlight both reported benefits and adverse effects reported following acute and chronic exposures. The data suggest that age is an important factor in both caffeine and taurine toxicity. Although the aged or diseased brain might benefit from taurine or caffeine supplementation, it appears that adolescents are not likely to benefit from supplementation and may, in fact, suffer ill effects from chronic ingestion of high doses. Additional work is needed though to address gaps in our understanding of how taurine affects females, since the majority of animal studies focused exclusively on male subjects.

Alcohol-Induced Impairment of Balance is Antagonized by Energy Drinks

BACKGROUND

The acute administration of alcohol reliably impairs balance and motor coordination. While it is common for consumers to ingest alcohol with other stimulant drugs (e.g., caffeine, nicotine), little is known whether prototypical alcohol-induced balance impairments are altered by stimulant drugs. The purpose of this study was to examine whether the coadministration of a high-caffeine energy drink with alcohol can antagonize expected alcohol-induced increases in body sway.

METHODS

Sixteen social drinkers (of equal gender) participated in 4 separate double-blind dose administration sessions that involved consumption of alcohol and energy drinks, alone and in combination. Following dose administration, participants completed automated assessments of balance stability (both eyes open and eyes closed) measured using the Biosway Portable Balance System. Participants completed several subjective measures including self-reported ratings of sedation, stimulation, fatigue, and impairment. Blood pressure and pulse rate were recorded repeatedly.

RESULTS

The acute administration of alcohol increased body sway, and the coadministration of energy drinks antagonized this impairment. When participants closed their eyes, alcohol-induced body sway was similar whether or not energy drinks were ingested. While alcohol administration increased ratings of sedation and fatigue, energy drink administration increased ratings of stimulation and reduced ratings of fatigue. Modest increases in systolic and diastolic blood pressure following energy drink administration were also observed.

CONCLUSIONS

Visual assessment of balance impairment is frequently used to indicate that an individual has consumed too much alcohol (e.g., as part of police-standardized field sobriety testing or by a bartender assessing when someone should no longer be served more alcohol). The current findings suggest that energy drinks can antagonize alcohol-induced increases in body sway, indicating that future work is needed to determine whether this observation regarding neuromotor functioning applies to alcohol in combination with all types of stimulant drugs.

Energy Drink and Alcohol mixed Energy Drink use among high school adolescents: Association with risk taking behavior, social characteristics

PURPOSE

The aims of the study were to: a) examine the prevalence of energy drink (ED) and alcohol mixed with energy drink (AmED) consumption; b) investigate the relationships between ED and AmED with alcohol, binge drinking and drugs accounting for at risk behaviors among a representative sample of Italian adolescents.

METHODS

A representative sample of 30,588 Italian high school students, aged 15-19years, was studied. Binary and multivariate logistic regression analyses were performed to determine the independent association of the potential predictors' characteristics with the ED and AmED drinking during the last year.

RESULTS

Respectively 41.4% and 23.2% of respondents reported drinking EDs and AmEDs in the last year. Multivariate analysis revealed that consumption of EDs and AmEDs during the last year were significantly associated with daily smoking, binge drinking, use of cannabis and other psychotropic drugs. Among life habits and risky behaviors the following were positively associated: going out with friends for fun, participating in sports, experiencing physical fights/accidents or injury, engaging in sexual intercourse without protection and being involved in accidents while driving.

CONCLUSIONS

This study demonstrates the popularity of ED and AmED consumption among the Italian school population aged 15-19years old: 4 out of 10 students consumed EDs in the last year and 2 out of 10 AmED. Multivariate analysis highlighted the association with illicit drug consumption and harming behaviors, confirming that consumption of EDs and AmEDs is a compelling issue especially during adolescence, as it can effect health as well as risk taking behaviors.

The Safety of Ingested Caffeine: A Comprehensive Review

Caffeine is the most widely consumed psychoactive drug in the world. Natural sources of caffeine include coffee, tea, and chocolate. Synthetic caffeine is also added to products to promote arousal, alertness, energy, and elevated mood. Over the past decade, the introduction of new caffeine-containing food products, as well as changes in consumption patterns of the more traditional sources of caffeine, has increased scrutiny by health authorities and regulatory bodies about the overall consumption of caffeine and its potential cumulative effects on behavior and physiology. Of particular concern is the rate of caffeine intake among populations potentially vulnerable to the negative effects of caffeine consumption: pregnant and lactating women, children and adolescents, young adults, and people with underlying heart or other health conditions, such as mental illness. Here, we review the research into the safety and safe doses of ingested caffeine in healthy and in vulnerable populations. We report that, for healthy adults, caffeine consumption is relatively safe, but that for some vulnerable populations, caffeine consumption could be harmful, including impairments in cardiovascular function, sleep, and substance use. We also identified several gaps in the literature on which we based recommendations for the future of caffeine research.

Intoxication-Related Alcohol Mixed with Energy Drink Expectancies Scale: Initial Development and Validation

BACKGROUND

Young adult use of alcohol mixed with energy drinks (AmEDs) has been linked with elevated risks of a constellation of problem behaviors. These risks may be conditioned by expectancies regarding the effects of caffeine in conjunction with alcohol consumption. The aim of this study was to describe the construction and psychometric evaluation of the Intoxication-Related AmED Expectancies Scale (AmED_EXPI), 15 self-report items measuring beliefs about how the experience of AmED intoxication differs from the experience of noncaffeinated alcohol (NCA) intoxication.

METHODS

Scale development and testing were conducted using data from a U.S. national sample of 3,105 adolescents and emerging adults aged 13 to 25. Exploratory and confirmatory factor analyses were conducted to evaluate the factor structure and establish factor invariance across gender, age, and prior experience with AmED use. Cross-sectional and longitudinal analyses examining correlates of AmED use were used to assess construct and predictive validity.

RESULTS

In confirmatory factor analyses, fit indices for the hypothesized 4-factor structure (i.e., Intoxication Management [IM], Alertness [AL], Sociability [SO], and Jitters [JT]) revealed a moderately good fit to the data. Together, these factors accounted for 75.3% of total variance. The factor structure was stable across male/female, teen/young adult, and AmED experience/no experience subgroups. The resultant unit-weighted subscales showed strong internal consistency and satisfactory convergent validity. Baseline scores on the IM, SO, and JT subscales predicted changes in AmED use over a subsequent 3-month period.

CONCLUSIONS

The AmED_EXPI appears to be a reliable and valid tool for measuring expectancies about the effects of caffeine during alcohol intoxication.

Time-dependent interacting effects of caffeine, diazepam, and ethanol on zebrafish behaviour

Zebrafish have become a popular animal model for behavioural pharmacology due to their small size, rapid development, and amenability to high throughput behavioural drug screens. Furthermore, water-soluble compounds can be administered via immersion of the fish in the drug solution, which provides a non-invasive drug delivery method. Numerous studies have demonstrated stimulant effects of alcohol. Diazepam and caffeine, on the other hand have been found to have inhibitory effect on locomotor activity in zebrafish. However, the time-dependent changes induced by these psychoactive drugs are rarely reported, and potential drug interactions have not been examined in zebrafish, despite the translational relevance of this question. In the current study, we examine time- and dose-dependent changes in zebrafish following exposure to caffeine, diazepam, and ethanol quantifying four different behavioural parameters over a 30min recording session. We subsequently analyze potential drug-drug interactions by co-administering the three drugs in different combinations. Our time-course and dose-response analyses for each of the three drugs represent so far the most detailed studies available serving as a foundation for future psychopharmacology experiments with zebrafish. Furthermore, we report significant interactions between the three drugs corroborating findings obtained with rodent models as well as in humans, providing translational relevance for the zebrafish model.

Effects of caffeine on alcohol reinforcement: beverage choice, self-administration, and subjective ratings

RATIONALE

Combining alcohol and caffeine is associated with increased alcohol consumption, but no prospective experimental studies have examined whether added caffeine increases alcohol consumption.

OBJECTIVES

This study examined how caffeine alters alcohol self-administration and subjective reinforcing effects in healthy adults.

METHODS

Thirty-one participants completed six double-blind alcohol self-administration sessions: three sessions with alcohol only (e.g., beverage A) and three sessions with alcohol and caffeine (e.g., beverage B). Participants chose which beverage to consume on a subsequent session (e.g., beverage A or B). The effects of caffeine on overall beverage choice, number of self-administered drinks, subjective ratings (e.g., Biphasic Alcohol Effects Scale), and psychomotor performance were examined.

RESULTS

A majority of participants (65%) chose to drink the alcohol beverage containing caffeine on their final self-administration session. Caffeine did not increase the number of self-administered drinks. Caffeine significantly increased stimulant effects, decreased sedative effects, and attenuated decreases in psychomotor performance attributable to alcohol. Relative to nonchoosers, caffeine choosers reported overall lower stimulant ratings and reported greater drinking behavior prior to the study.

CONCLUSIONS

Although caffeine did not increase the number of self-administered drinks, most participants chose the alcohol beverage containing caffeine. Given the differences in subjective ratings and pre-existing differences in self-reported alcohol consumption for caffeine choosers and nonchoosers, these data suggest that decreased stimulant effects of alcohol and heavier self-reported drinking may predict subsequent choice of combined caffeine and alcohol beverages. These predictors may identify individuals who would benefit from efforts to reduce risk behaviors associated with combining alcohol and caffeine.

Faster self-paced rate of drinking for alcohol mixed with energy drinks versus alcohol alone

The consumption of alcohol mixed with energy drinks (AmED) has been associated with higher rates of binge drinking and impaired driving when compared with alcohol alone. However, it remains unclear why the risks of use of AmED are heightened compared with alcohol alone even when the doses of alcohol consumed are similar. Therefore, the purpose of this laboratory study was to investigate if the rate of self-paced beverage consumption was faster for a dose of AmED versus alcohol alone using a double-blind, within-subjects, placebo-controlled study design. Participants (n = 16) of equal gender who were social drinkers attended 4 separate test sessions that involved consumption of alcohol (1.97 ml/kg vodka) and energy drinks, alone and in combination. On each test day, the dose assigned was divided into 10 cups. Participants were informed that they would have a 2-h period to consume the 10 drinks. After the self-paced drinking period, participants completed a cued go/no-go reaction time (RT) task and subjective ratings of stimulation and sedation. The results indicated that participants consumed the AmED dose significantly faster (by ∼16 min) than the alcohol dose. For the performance task, participants' mean RTs were slower in the alcohol conditions and faster in the energy-drink conditions. In conclusion, alcohol consumers should be made aware that rapid drinking might occur for AmED beverages, thus heightening alcohol-related safety risks. The fast rate of drinking may be related to the generalized speeding of responses after energy-drink consumption. (PsycINFO Database Record