ALDH2*2 is associated with a decreased likelihood of alcohol-induced blackouts in Asian American college students

Associations of ADH1B and ALDH2 genotypes and alcohol flushing with drinking history, withdrawal symptoms, and ICD-10 criteria in Japanese alcohol-dependent men

OBJECTIVES

Given the high prevalence of fast-metabolizing alcohol dehydrogenase-1B*2 (ADH1B*2) and inactive aldehyde dehydrogenase-2*2 (ALDH2*2) alleles in East Asians, we evaluated how the ADH1B/ALDH2 genotypes and alcohol flushing might affect the development of alcohol dependence (AD).

METHODS

We evaluated how the ADH1B/ALDH2 genotypes and self-reported alcohol flushing affected history of drinking events and withdrawal symptoms and ICD-10 criteria in 4116 Japanese AD men.

RESULTS

The ADH1B*1/*1 group and ALDH2*1/*1 group were 1-5 years younger than the ADH1B*2(+) and ALDH2*1/*2 groups, respectively, for all of the ages at onset of habitual drinking, blackouts, daytime drinking, uncontrolled drinking, withdrawal symptoms, and first treatment for AD, and the current age. Blackouts were more common in the ADH1B*1/*1 group and ALDH2*1/*1 group. Daytime drinking, uncontrolled drinking, and withdrawal symptoms, such as hand tremor, sweating, convulsions, and delirium tremens/hallucinations were more common in the ADH1B*1/*1 group. The ADH1B*1/*1 was positively associated with the ICD-10 criteria for 'tolerance' and 'withdrawal symptoms'. The ADH1B*1/*1 group and ALDH2*1/*2 group had a larger ICD-10 score. Never flushing was reported by 91.7% and 35.2% of the ALDH2*1/*1 and ALDH2*1/*2 carriers, respectively. After a 1-2-year delay in the onset of habitual drinking in the former-/current-flushing group, no differences in the ages of the aforementioned drinking milestones were found according to the flushing status.

CONCLUSION

The ADH1B*1/*1 and ALDH2*1/*1 accelerated the development of drinking events and withdrawal symptoms in Japanese AD patients. ICD-10 score was larger in the ADH1B*1/*1 group and ALDH2*1/*2 group. The effects of alcohol flushing on drinking events were limited.

Psychosocial Motivators for Moderate Drinking among Young Asian Flushers in Singapore

Asians are more susceptible to alcohol flush syndrome and its associated health risks because they are genetically predisposed towards it. Guided by the theory of planned behaviour, this research examined the psychosocial factors associated with moderate alcohol consumption, in order to inform the development of a health campaign targeting young Asian "flushers" in Singapore. We employed a mixed-method design comprising an online survey and focus group discussions. The survey results identified perceived behavioural control as the most salient belief associated with moderate drinking intentions, particularly for Asian flushers. Although Asian flushers had more positive attitudes towards, and perceived behavioural control about drinking in moderation, they were more likely to consider that their peers disapprove of such a practice, compared to non-flushers. Additionally, Asian flushers did not consider themselves as having a higher risk of long-term health effects from alcohol consumption than non-Flushers despite their actual high-risk status. Focus group findings suggest that young Asian flushers have poor knowledge of, and skills associated with moderate drinking, in addition to feeling self-imposed social pressure. The study findings provide practical insights into bridging the information gap on Asian flush and promoting Asian flushers' drinking in moderation.

Primary Reason for Drinking Among Current, Former, and Never Flushing College Students

Alcohol consumption among individuals who experience a flushing response (reddening of the face, nausea, dizziness, headache, anxiety, and increased heartbeat) can result in serious health problems. However, studies on reasons for drinking among flushers, especially in the college context, are limited. Thus, this study investigated the association between primary reason for drinking and alcohol use among a nationally representative sample of current, former, and never flushing college students. The aim was to measure whether college students with current or former experience of facial flushing have different primary reasons for drinking compared to students with no experience of facial flushing. We surveyed and analyzed the data of 4590 students in a nationally representative sample of 82 colleges in South Korea. Multiple regression analysis was used to identify the association between primary reason for drinking and alcohol intake. Alcohol intake was measured using the Alcohol Use Disorders Identification Test (AUDIT). Among 1537 current (33.5%), 152 former (3.3%), and 2901 (63.2%) never flushers, mean AUDIT scores were 7.715 ± 5.434, 11.039 ± 6.405, and 10.465 ± 5.779, respectively. Current flushers had significantly higher AUDIT scores when drinking for pleasure (β = 2.696, p < 0.0001) or stress/depression (β = 2.578, p < 0.0001). Primary reasons for drinking were not associated with alcohol intake for former flushers. Never flushers had significantly higher AUDIT scores when drinking for pleasure (β = 2.696, p < 0.0001), stress/depression (β = 2.578, p < 0.0001), or boredom (β = 0.740, p = 0.029) than peer pressure. Our results suggest that former and never flushers consume higher amounts of alcohol on average than never flushers. For current flushers, drinking for pleasure or stress/depression may increase alcohol intake, while for never flushers, drinking for pleasure, stress/depression, as well as boredom may have the same effect.

Alcohol-related blackouts among college students: impact of low level of response to alcohol, ethnicity, sex, and environmental characteristics

Objective:

To explore how a genetically-influenced characteristic (the level of response to alcohol [LR]), ethnicity, and sex relate to environmental and attitudinal characteristics (peer drinking [PEER], drinking to cope [COPE], and alcohol expectancies [EXPECT]) regarding future alcohol-related blackouts (ARBs).

Methods:

Structural equation models (SEMs) were used to evaluate how baseline variables related to ARB patterns in 462 college students over 55 weeks. Data were extracted from a longitudinal study of heavy drinking and its consequences at a U.S. university.

Results:

In the SEM analysis, female sex and Asian ethnicity directly predicted future ARBs (beta weights 0.10 and -0.11, respectively), while all other variables had indirect impacts on ARBs through alcohol quantities (beta weights ~ 0.23 for European American ethnicity and low LR, 0.21 for cannabis use and COPE, and 0.44 for PEER). Alcohol quantities then related to ARBs with beta = 0.44. The SEM explained 23% of the variance.

Conclusion:

These data may be useful in identifying college students who are more likely to experience future ARBs over a 1-year period. They enhance our understanding of whether the relationships of predictors to ARBs are direct or mediated through baseline drinking patterns, information that may be useful in prevention strategies for ARBs.

How Social Reactions to Alcohol-Related Facial Flushing Are Affected by Gender, Relationship, and Drinking Purposes: Implications for Education to Reduce Aerodigestive Cancer Risks

Alcohol-related facial flushing is a sign of compromised alcohol metabolism and increased risk of certain cancers. This project examined how facial flushing might be used to reduce alcohol use to lower cancer risks. Interviews with Chinese university students identified gender, friendship, and drinking purpose as important variables related to whether someone would encourage a person who flushes when drinking alcohol to stop or reduce their drinking. A questionnaire was developed that incorporated these variables into 24 drinking scenarios in which someone flushed while drinking. Students responded whether they would (a) encourage the flusher to stop or drink less; (b) do nothing while wishing they could; or (c) do nothing because there was no need. Analysis of survey responses from 2912 university students showed a three-way interaction of the variables and implied that the probability students will intervene when a drinker flushes was highest when the flusher was a female, a close friend, and the drinking purpose was for fun and lowest if the flusher was a male, the friendship was general, and the drinking purpose was risky. The results provide important details about the social factors affecting how other people respond to a person who flushes when drinking alcohol. This information is useful for those considering ways to reduce and prevent aerodigestive cancers through education and information programs.

Alcohol-related blackouts across 55 weeks of college: Effects of European-American ethnicity, female sex, and low level of response to alcohol

BACKGROUND

While high blood alcohol concentrations (BACs) are required for alcohol-related blackouts (ARBs), additional characteristics also contribute to the risk, including a person's ethnicity, sex, and phenotypes relating to heavier drinking. Few prospective studies of ARBs have evaluated how these additional characteristics interact.

METHOD

Data regarding 398 European American (EA), Asian and Hispanic students were extracted from a 55-week prospective study of different approaches to decrease heavy drinking among college freshmen. Information on past month ARB frequency was determined at 8 assessments. While controlling for the prior month maximum BAC and active education vs. control group assignment, the patterns and intensities of ARBs over time across ethnic groups were evaluated with ANOVA at each follow-up for the full sample, and then separately by sex and then by low vs. high levels of response to alcohol status (LR). The overall pattern of ARBs over time was evaluated with a 3 ethnic groups by 2 sexes by 2 LR status by 8 time points mixed-design ANOVA.

RESULTS

Higher rates of ARBs over time were associated with EA ethnicity, female sex and a low LR to alcohol, with the ethnic differences in ARBs most robust in females and drinkers with high LRs. Participation in education programs aimed at heavy drinking was associated with decreases in ARBs.

CONCLUSIONS

The data indicate that in addition to BACs achieved, propensities toward ARBs relate to complex interactions between additional risk factors, including ethnicity, sex, and LR status.

Alcohol-Induced Blackouts: A Review of Recent Clinical Research with Practical Implications and Recommendations for Future Studies

BACKGROUND

Alcohol-induced blackouts, or memory loss for all or portions of events that occurred during a drinking episode, are reported by approximately 50% of drinkers and are associated with a wide range of negative consequences, including injury and death. As such, identifying the factors that contribute to and result from alcohol-induced blackouts is critical in developing effective prevention programs. Here, we provide an updated review (2010 to 2015) of clinical research focused on alcohol-induced blackouts, outline practical and clinical implications, and provide recommendations for future research.

METHODS

A comprehensive, systematic literature review was conducted to examine all articles published between January 2010 through August 2015 that focused on vulnerabilities, consequences, and possible mechanisms for alcohol-induced blackouts.

RESULTS

Twenty-six studies reported on alcohol-induced blackouts. Fifteen studies examined prevalence and/or predictors of alcohol-induced blackouts. Six publications described the consequences of alcohol-induced blackouts, and 5 studies explored potential cognitive and neurobiological mechanisms underlying alcohol-induced blackouts.

CONCLUSIONS

Recent research on alcohol-induced blackouts suggests that individual differences, not just alcohol consumption, increase the likelihood of experiencing an alcohol-induced blackout, and the consequences of alcohol-induced blackouts extend beyond the consequences related to the drinking episode to include psychiatric symptoms and neurobiological abnormalities. Prospective studies and a standardized assessment of alcohol-induced blackouts are needed to fully characterize factors associated with alcohol-induced blackouts and to improve prevention strategies.

Effects of ALDH2∗2 on alcohol problem trajectories of Asian American college students

The variant aldehyde dehydrogenase allele, ALDH2∗2, consistently has been associated with protection against alcohol dependence, but the mechanism underlying this process is not known. This study examined growth trajectories of alcohol consumption (frequency, average quantity, binge drinking, maximum drinks) and problems over the college years and then tested whether the ALDH2 genotype mediated or moderated the relationship between alcohol consumption and problems. Asian American college students (N = 433) reported on their drinking behavior in their first year of college and then annually for 3 consecutive years. Alcohol consumption and problems increased over the college years for both those with and without ALDH2∗2, but having an ALDH2∗2 allele was associated with less of an increase in problems over time. A mediation model was supported, with ALDH2∗2 group differences in problems fully accounted for by differences in frequency of binge drinking. Findings also supported a moderation hypothesis: All four alcohol consumption variables were significant predictors of subsequent alcohol problems, but these relationships were not as strong in those with ALDH2∗2 as in those without ALDH2∗2. Our findings suggest that the interplay between ALDH2∗2 and drinking-related problems is complex, involving both mediation and moderation processes that reduce the likelihood of developing problems via reduction of heavy drinking as well as by altering the relationship between alcohol consumption and problems. Results of this longitudinal study provide evidence that what seems like a relatively straightforward effect of a diminished ability to metabolize alcohol on drinking behavior is actually dependent on behavior and developmental stage.

The educational potential of alcohol-related flushing among Chinese young people

Aim: This paper describes Chinese university students' understanding of the meaning of the alcohol-related flushing response and how they reacted to their own and someone else's flushing in a group drinking situation. Method: The researcher surveyed 530 Chinese university students about their understanding of flushing and their perception of how people respond to a person who visibly flushes while drinking alcohol. Findings: Most students did not know about the physiological cause of flushing. There were significant gender differences in both reactions to and perception of responses to a person who flushes. There was no direct relationship between flushing and drinking behaviour.

CONCLUSIONS

This description of flushing behaviour and responses to a flushing person is discussed in terms of educational opportunities to change behaviours that could reduce the cancer related risks of this visibly at-risk group.

Development of a real-time repeated-measures assessment protocol to capture change over the course of a drinking episode

AIMS

We report on the development of a real-time assessment protocol that allows researchers to assess change in BrAC, alcohol responses, behaviors, and contexts over the course of a drinking event.

METHOD

We designed a web application that uses timed text messages (adjusted based on consumption pattern) containing links to our website to obtain real-time participant reports; camera and location features were also incorporated into the protocol. We used a transdermal alcohol sensor device along with software we designed to convert transdermal data into estimated BrAC. Thirty-two college students completed a laboratory session followed by a 2-week field trial.

RESULTS

Results for the web application indicated we were able to create an effective tool for obtaining repeated measures real-time drinking data. Participants were willing to monitor their drinking behavior with the web application, and this did not appear to strongly affect drinking behavior during, or 6 weeks following, the field trial. Results for the transdermal device highlighted the willingness of participants to wear the device despite some discomfort, but technical difficulties resulted in limited valid data.

CONCLUSION

The development of this protocol makes it possible to capture detailed assessment of change over the course of naturalistic drinking episodes.

Use of protective behavioral strategies and reduced alcohol risk: examining the moderating effects of mental health, gender, and race

Recent research indicates that protective behavioral strategies (PBS)-previously established as effective self-regulating tools for reducing alcohol risk among college students-may be especially useful for students with poor mental health, who are shown to be at heightened risk for alcohol-related harm. The current study examined the moderating influence of mental health (depression and anxiety severity), gender, and race (White, Asian) in the relationship between PBS use and alcohol-related negative consequences. Participants were 1,782 undergraduate students from two West Coast universities who reported past-month incidence of heavy episodic drinking (HED). Students reported on their drinking, experience of alcohol-related consequences, use of PBS, and depression and anxiety symptomatology. Overall, results demonstrated that among participants experiencing depression or anxiety, greater PBS utilization was associated with significantly lower levels of alcohol-related consequences, even after controlling for drinking and other predictors. However, findings also revealed important distinctions in the potential effectiveness of PBS by depression/anxiety severity and racial-gender subgroup, such that Asian men with poor mental health appeared to garner unique and substantial benefit (i.e., lesser consequences) from increased PBS use. Further, PBS were found to offer substantial protective benefit for White females, irrespective of mental health. This study points to the potential for targeted PBS-specific skills training and interventions to minimize alcohol-related risks faced by the growing subpopulation of college students experiencing psychological distress, and further highlights important race and gender differentials.

Prevention for college students who suffer alcohol-induced blackouts could deter high-cost emergency department visits

Fifty percent of college students who drink report alcohol-induced blackouts, and alcohol abusers in general put a heavy burden on the medical care system. Using data drawn from a randomized, controlled alcohol intervention trial at five university sites, our study quantified the costs of visits to emergency departments by college students who experienced blackouts from drinking alcohol. Of 954 students in the study, 52 percent of males and 50 percent of females at the outset of the study had experienced an alcohol-induced blackout in the past year. Of 404 emergency department visits among the study participants over a two-year observation period, about one in eight were associated with blackout drinking. Injuries ranged from broken bones to head and brain injuries requiring computed tomography. We calculate that on a large university campus having more than 40,000 students, blackout-associated emergency department visit costs would range from $469,000 to $546,000 per year. We conclude that blackouts are a strong predictor of emergency department visits for college drinkers and that prevention efforts aimed at students with a history of blackouts might reduce injuries and emergency department costs.

Social meaning of alcohol-related flushing among university students in China

This study explored drinking patterns, alcohol-related flushing, and ways students themselves and other people respond to flushing in drinking situations. Of 1080 Chinese undergraduate university students given the survey questionnaire, 725 (67.1%) returned the completed surveys. Eighty percent of the students were drinkers (93% of males and 69% of females); 68% of the drinkers were flushers. Most of the students (59.3%) said flushing had no special meaning, that is, would ignore flushing; 54% of the flushers said they could keep drinking "but less" when they flush; 27% of the students said that a flushing person should stop drinking; however, if the flushing person is a girl, 89% of the students said the girl should drink less or stop. If the flushing person was a boy, 61% of students said he should drink less or stop. The data do suggest gender differences in the understanding of and social reaction to alcohol-related flushing, and these differences raise interesting questions as to how flushing acts as a potential protective factor against alcohol misuse.

The role of acetaldehyde in human psychomotor function: a double-blind placebo-controlled crossover study

BACKGROUND

Acetaldehyde, the first product of ethanol metabolization, is a biologically active compound, but the behavioral properties of acetaldehyde in humans are largely undefined. We investigated the acute effects of both alcohol and acetaldehyde on psychomotor functions related to automobile driving skills.

METHODS

Twenty-four men were selected through genotyping; one-half had the ALDH2*1/*1 (active form) genotype and one-half had the ALDH2*1/*2 (inactive form) genotype. In a double-blind placebo-controlled crossover design, each subject was administered one of the following doses of alcohol: .25 g/kg, .5 g/kg, or .75 g/kg or a placebo in four trials that took place at 1-week intervals. Blood ethanol concentration (BEC) and blood acetaldehyde concentration (BAAC) were measured nine times, and psychomotor function tests (critical flicker fusion threshold, choice reaction time, compensatory tracking task, and digit symbol substitution test) were assessed seven times in total over 4 hours after study drug ingestion.

RESULTS

After the consumption of alcohol, BEC was comparable in the two subject groups, whereas BAAC was significantly higher in subjects with ALDH2 *1/*2 than in those with ALDH2 *1/*1. The psychomotor performance of subjects with ALDH2*1/*2 was significantly poorer than that of subjects with ALDH2*1/*1. Significant correlations between psychomotor performance and both BEC and BAAC were observed. However, in the linear regression analysis, BAAC significantly predicted poorer psychomotor performance, whereas BEC was not associated with any measure of psychomotor function.

CONCLUSIONS

Acetaldehyde might be more important than alcohol in determining the effects on human psychomotor function and skills.