Predictors of Patterns of Alcohol-Related Blackouts Over Time in Youth From the Collaborative Study of the Genetics of Alcoholism: The Roles of Genetics and Cannabis

A longitudinal study of the relationship between alcohol-related blackouts and attenuated structural brain development

PURPOSE

Alcohol-related blackouts (ARBs) are common in adolescents and emerging adults. ARBs may also be indicative of persistent, alcohol-related neurocognitive changes. This study explored ARBs as a predictor of altered structural brain development and associated cognitive correlates.

METHODS

Longitudinal growth curve modeling estimated trajectories of brain volume across 6 years in participants from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study (n = 800, 213 with lifetime ARB history). While controlling for demographics and overall alcohol use, ARB history was analyzed as a predictor of brain volume growth in regions associated with alcohol-related cognitive change. Post hoc analyses examined whether ARBs moderated relationships between brain morphology and cognition.

RESULTS

ARBs significantly predicted attenuated development of fusiform gyrus and hippocampal volume at unique timepoints compared to overall alcohol use. Alcohol use without ARBs significantly predicted attenuated fusiform and hippocampal growth at earlier and later timepoints, respectively. Despite altered development in regions associated with memory, ARBs did not significantly moderate relationships between brain volume and cognitive performance.

CONCLUSION

ARBs and overall alcohol use predicted altered brain development in the fusiform gyrus and hippocampus at different timepoints, suggesting ARBs represent a unique marker of neurocognitive risk in younger drinkers.

Latent Trajectories of Persistence of Cannabis Use Across Four Decades in 329 Men From the San Diego Prospective Study

OBJECTIVE

These analyses use data from a 40-year prospective study to extend information into the sixth and seventh decades of life regarding latent trajectory classes of cannabis use and predictors of those classes.

METHOD

Data from the San Diego Prospective Study were analyzed for 329 men of European and Hispanic ethnicity who had used cannabis at about age 23 at study entry (Time 1) and who were interviewed about every 5 years through about age 60 to 70. Latent classes of cannabis use trajectories were evaluated using latent class growth analyses, baseline predictors of class membership were determined, and significant predictors of each class were established using logistic regression analyses.

RESULTS

Four latent classes were identified ranging from 12.5% with cannabis use at every follow-up to 25.8% with no use after Time 1. Eight of 14 Time 1 predictors differed significantly across the trajectory classes, including five (age, marital status, religious identity, intensity of cannabis use, and sensation seeking) that significantly contributed to regression analyses when all significant predictors were considered together.

DISCUSSION

Forty-two percent of participants continued using cannabis long-term, including one in eight who used it at every follow-up. Predictors of continued use and identification of those most likely to stop required gathering information on a range of demographic, prior substance use, and personality characteristics.

CONCLUSIONS

Considering the potential enhanced dangers of cannabis use in later life, the high rate of continued use over four decades implies that clinicians should ask all older patients about recent cannabis use, especially if they had used it in their 20s.

Associations between blackout drinking and self-reported everyday cognition among young adults

INTRODUCTION

Blackout drinking, or alcohol-induced memory loss during at least some part of a drinking occasion, is common among young adults and associated with negative alcohol-related consequences. One potential unique effect of blackout drinking episodes could be prolonged, general difficulties forming new memories through impairments in encoding, storage, or retrieval. The current study examined preliminary associations between blackout drinking and self-reported everyday cognitive functioning (i.e., memory lapses, non-memory cognitive difficulties, cognitive concerns) among a sample of young adults. We also examined the moderating role of key factors linked to blackout drinking: gender and frequent simultaneous alcohol and cannabis use.

METHODS

Participants (N = 479; 53% women) were aged 18-30 who reported past-year blackout drinking. Participants completed an online survey through Qualtrics Panels.

RESULTS

More frequent blackout experiences were found to be significantly related to more memory lapses, more non-memory cognitive difficulties, and more cognitive concerns even after controlling for typical alcohol use behavior. Men and individuals reporting frequent simultaneous use indicated stronger relationships between blackout drinking frequency and cognitive outcomes.

DISCUSSION AND CONCLUSIONS

Findings add to the growing body of literature supporting the uniquely hazardous effects of blackout drinking and identify individuals at heightened risk of harms. Given that associations between blackout drinking frequency and everyday cognitive functioning were identified even among a young adult sample suggests that blackout drinking may be a risky behavior that links to poorer cognitive functioning.

Prevalence and correlates of alcohol-induced blackout in a diverse sample of veterans

BACKGROUND

Alcohol-induced blackouts have been associated concurrently and prospectively with alcohol-related harm. Although rates of heavy drinking among military samples tend to be comparable or higher than rates among civilian samples, the prevalence and correlates of blackout in the military population are understudied.

METHODS

Veterans (N = 241, 29% female, 39% Black) reported on their alcohol consumption and mental health as part of a larger health-related study among veterans. In this secondary analysis, we tested theoretically and empirically informed predictors (gender, drinking quantity, and other drug use) and consequences [depression, posttraumatic stress disorder (PTSD)] of alcohol-induced blackout. Given the diversity of the sample, potential roles of racial/ethnic discrimination and drinking to cope in alcohol-induced blackout were also tested.

RESULTS

Past-year prevalence of alcohol-induced blackout was 53% among veterans who drank alcohol and 68% among those who screened positive for hazardous drinking. Everyday experience of racial discrimination was the strongest concurrent predictor of alcohol-induced blackout. Drinking quantity and use of other drugs were significant correlates only in bivariate models. Controlling for gender, race, drinking quantity, other drug use, and discrimination, blackout frequency was significantly associated with symptoms of depression, but not symptoms of PTSD. Both blackout and racial discrimination were associated with drinking to cope.

CONCLUSIONS

The prevalence and correlates of alcohol-induced blackout among veterans are largely consistent with those documented in civilian and young adult populations. Among racially diverse groups, racial discrimination may be more strongly associated with mental health symptoms than alcohol consumption or acute alcohol consequences such as blackout.

Past year high-intensity drinking moderates the association between simultaneous alcohol and marijuana use and blackout frequency among college students

Objective: The role of simultaneous alcohol and marijuana (SAM) use in the experience of blackouts among college students is unclear. To clarify discrepancies, the current study evaluated whether the association between SAM user status and blackouts was moderated by high-intensity drinking (HID). Participants and Methods: College students (N = 1,224; 63.7% female) reported on their past year experiences of blackout, marijuana use, SAM use, and HID (i.e., drinking at least twice the binge threshold). Results: SAM users had more past year blackouts than non-SAM users, but this effect was only significant among SAM users who had engaged in HID in the past year (nonbinge: F(5,37) = 0.50, p = 0.49; binge: F(5,138) = 0.23, p = 0.63; HID: F(5,328) = 4.52, p = 0.03). Conclusions: Effects of SAM user status on the experience of alcohol-related blackouts may be limited to individuals who engage in HID.

Polysubstance Use Patterns among Outpatients Undergoing Substance Use Disorder Treatment: A Latent Class Analysis

Substance Use Disorders (SUDs) pose significant challenges to both individuals and society at large. The primary focus of existing research with clinical SUD populations has been on individual substances, but research is required to better understand the profiles of individuals who use different substances simultaneously. The purpose of the current study was, therefore, to identify patterns of use among subjects (n = 1025) who reported using multiple substances by adopting a Latent Class Analysis (LCA) methodology. The Addiction Severity Index (ASI-lite) was included as a measure of substance misuse, we performed LCA to identify patterns of substance use through the administration of the ASI-Lite. Responses were collected from the following substances: alcohol, cannabis/cannabinoids, opioids and heroin, and cocaine. Results identified two latent classes: (1) alcohol use dominant, and (2) poly-abuser use dominants. Class 1 represented 60.0% of the sample and refers to individuals with the dominant use of alcohol, of those a higher proportion (47%) reported low-frequency use (1 to 7 days per month) and 26% reported a frequency of use of 24 to 30 days per month. Furthermore, 18% used alcohol in combination with cocaine. Class 2 represents 40.0% of the sample. This class is characterized by low-frequency and high-frequency users of several substances. The results obtained highlight the importance of deepening the study of the concomitant use of substances in individuals with SUDs to better understand the health risk of the combined use of two or more substances.

A Longitudinal Examination of Alcohol-Related Blackouts as a Predictor of Changes in Learning, Memory, and Executive Function in Adolescents

INTRODUCTION

In adolescents, the relationship between alcohol-related blackouts (ARBs) and distinct cognitive changes lasting beyond intoxication is unclear. We examined ARBs as a predictor of persistent changes in the development of learning, memory, and executive function in participants from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study.

METHODS

Descriptive analyses of the NCANDA sample (N = 831, 50.9% female, 12-21 years at baseline) identified ARB patterns within participants with an ARB history (n = 106). Latent growth curve modeling evaluated ARB-related performance changes on four neuropsychological measures across five years, excluding baseline data to reduce the magnitude of practice effects over time (n = 790). Measures included the Penn Conditional Exclusion Test (PCET), Penn Letter N-back Test (PLBT), Penn Facial Memory Test immediate (PFMT_i), and delayed (PFMT_d) recognition trials, and the Rey Complex Figure Test copy (RCFT_c), immediate recall (RCFT_i), and delayed recall (RCFT_d) trials. Multivariate models were fit for raw accuracy scores from each measure, with ARB history (i.e., presence of past-year ARBs) as the main independent variable. Age, sex, race, socioeconomic status, assessment site, and alcohol use (i.e., past-year frequency) were included as covariates. Interaction effects between ARB history and alcohol use frequency were tested.

RESULTS

By year five, 16% of participants had experienced at least one ARB (59% of whom reported > 1 ARB and 57% of whom had an ARB lasting > 1 h). After controlling for demographics and alcohol use, ARB history predicted attenuated PFMT_d performance growth at year one. Interaction effects between ARB history and alcohol use frequency predicted attenuated PFMT_d performance growth at years one and two. ARB history predicted attenuated RCFT_i and RCFT_d performance growth by year four, but not PCET or PLBT performance over time. By contrast, greater past-year alcohol use predicted attenuated PFMT_i and PFMT_d performance growth between years two and four in adolescents without an ARB history.

CONCLUSION

We found that ARBs predict distinct, lasting changes in learning and memory for visual information, with results suggesting that the developing brain is vulnerable to ARBs during adolescence and emerging adulthood.

Trajectories of alcohol-induced blackouts in adolescence: early risk factors and alcohol use disorder outcomes in early adulthood

BACKGROUND AND AIMS

Experience of alcohol-induced memory blackouts in adolescence may be an important risk factor for later harms. This longitudinal study (i) modelled trajectories of alcohol-related blackouts throughout adolescence, (ii) explored early-adolescent predictors of blackout trajectories and (iii) examined the association between blackout trajectories and alcohol use disorder (AUD) symptoms.

DESIGN

Longitudinal study in which data from six annual surveys of a longitudinal cohort of Australian adolescents were used to model latent class growth trajectories of blackouts, adjusting for alcohol consumption frequency and typical quantity. Regression models were used to determine whether parent, child and peer factors at baseline (mean age = 12.9) predicted profiles of blackout trajectory membership and whether blackout trajectories predicted meeting criteria for AUD in early adulthood (mean age = 19.8).

SETTING AND PARTICIPANTS

Australian adolescents (n = 1821; mean age = 13.9-18.8 years).

MEASUREMENTS

Alcohol-related blackouts, alcohol consumption frequency, typical consumption quantity and DSM-5 AUD in early adulthood were all self-reported.

FINDINGS

We identified a three-class solution: delayed alcohol initiation, rare blackouts (n = 701; 38.5%); early initiation, rare blackouts (n = 869; 47.7%); and early initiation, increasing blackouts (n = 251; 13.8%). Female sex was associated with increased risk of early initiation, increasing blackouts relative to delayed initiation, rare blackouts [relative risk ratio (RRR) = 3.90; 99.5% confidence interval (CI) = 1.96, 7.76] and relative to early initiation, rare blackouts (RRR = 2.89; 99.5% CI = 1.42, 5.87). Early initiation, rare blackouts [odds ratio (OR) = 1.96; 99.5% CI = 1.17, 3.29] and early initiation, increasing blackouts (OR = 4.93; 99.5% CI = 2.32, 10.48) were each associated with increased odds of meeting criteria for AUD in early adulthood relative to delayed initiation, rare blackouts. Early initiation, increasing blackouts was associated with increased odds of meeting criteria for AUD in early adulthood relative to early initiation, rare blackouts (OR = 2.51; 99.5% CI = 1.18, 5.38).

CONCLUSIONS

Females in Australia appear to be at higher risk of adolescent alcohol-related blackouts independent of alcohol consumption levels and age of initiation. Alcohol-related blackouts may be associated with later alcohol use disorder.

Intentions and motives to experience alcohol-induced blackout among young adults in college

Blackouts are typically considered a negative consequence of alcohol use. Yet some college students report consuming alcohol with the intention of blacking out. This study examined intentions and motives for blackout drinking among young adults in college. College students with a past-year history of blackout (N = 350, 56% female, 73% White) completed an anonymous online survey. Descriptive statistics were used to examine the incidence of blackout intentions, and individuals who did and did not report future blackout intentions were then compared on drinking patterns, depressive symptoms, social norms, and outcome expectancies. Overall, 135 participants (39%) reported consuming alcohol in the past 30 days with the intention of losing memory of the night's events, and 107 (31%) reported blackout intentions in the next 30 days. When asked (via open text box) to indicate their motives for past blackout intentions, the majority of participants provided responses that fit with coping, social, or enhancement drinking motives. A larger proportion of men than women reported blackout intentions. As a group, those reporting future blackout intentions reported heavier, more frequent, and more problematic drinking, as well as more symptoms of depression and more positive (but not negative) outcome expectancies. A substantial subset of college students reporting a blackout in the past year also endorsed intentions to experience a blackout in the next 30 days. Given strong associations between intentions and subsequent behavior, interventions targeting blackout styles of drinking are warranted. The extent to which "blackout" drinking motives differ from traditional drinking motives is unclear. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

The Search for Contributors to Low Rates of Recognition of Paternal Alcohol Use Disorders in Offspring From the San Diego Prospective Study

BACKGROUND

The most efficient approach for establishing family histories (FHs) asks informants about disorders in their relatives (a Family History Method [FHM]). However, FHMs underestimate family diagnoses. We evaluated if accuracies of young adult offspring report of their father's alcohol use disorders (AUDs) related to the age, sex, education, and/or substance-related patterns/problems of either the young adult informants or their AUD fathers.

METHODS

Data from the San Diego Prospective Study (SDPS), a multigenerational 35-year investigation, compared father/offspring pairs where the proband father's alcohol problems were correctly (Group 1) or incorrectly (Group 2) noted by offspring. In the key analysis, Group 1 versus 2 results were entered into bootstrapped backward logistic regression analyses predicting Group 1 membership.

RESULTS

Five proband and one offspring characteristic were associated with correct identification of their father's alcohol problems. None of these related to age, education, or sex. Characteristics associated with correct FHM diagnoses included the father's FH of AUDs, self-report of drinking despite social/interpersonal or physical/psychological alcohol-related problems, spending much time related to alcohol, and his having a religious preference. The single offspring item predicting correct identification of the father's problems was the number of DSM alcohol problems of the offspring.

CONCLUSIONS

In the SDPS, FHM sensitivity was most closely related to the father's drinking characteristics, not the offspring characteristics. While unique aspects of SDPS families potentially limit generalizability of results, the data demonstrate how the FHM can offer important initial steps in the search for genetically related AUD risks in a subset of families.

Identifying subtypes of cannabis users based on simultaneous polysubstance use

BACKGROUND

Cannabis use patterns vary considerably, with many users reporting simultaneous and non-simultaneous use (co-use) of other substances. Despite this, little research has examined the extent to which subtypes of cannabis users may be identified based on their simultaneous and co-use behaviors.

METHODS

The sample consisted of adult Australian twins and siblings who reported lifetime cannabis use (n = 2590). A latent class analysis was conducted to determine subtypes of cannabis users based on five indicators of substance co-use and simultaneous use. Adolescent correlates (age of substance initiation and conduct disorder) and adult correlates (substance use/disorder and depression) of class membership were assessed. Twin similarity for class membership was also examined.

RESULTS

Four subtypes of users were identified: 1) alcohol co-users, 2) simultaneous alcohol users, 3) simultaneous tobacco users, and 4) simultaneous alcohol, tobacco, and drug users. Compared to co-users of alcohol, simultaneous alcohol users were at increased risk for alcohol problems. Patterns of use that involved simultaneous tobacco and cannabis use (i.e., simultaneous tobacco users and simultaneous alcohol, tobacco, and drug users) were associated with the most problematic outcomes, including substance use and disorder. There was evidence for genetic influences (12-58%) on cannabis use patterns, with higher concordance for latent class membership among monozygotic compared to dizygotic twins (χ2 (1) = 7.19, p = 0.007).

CONCLUSIONS

The current study identified four classes of cannabis users at varying degrees of risk. Results suggest that simultaneous tobacco and cannabis use may be especially associated with deleterious outcomes.

Individual and Social Factors Related to Trajectories of Blackouts among Underage Drinkers in the Emergency Department

AIMS

Alcohol-related blackouts can result in acute injuries and other negative outcomes. Among underage risky drinkers, we examined longitudinal trajectories of blackout frequency following an emergency department (ED) visit, and identified baseline characteristics associated with blackout trajectory membership.

METHODS

Participants (ages 14-20; N = 836) attending an ED who screened positive for risky drinking and enrolled in a randomized-controlled trial of brief alcohol interventions were assessed at baseline, 3-, 6-, and 12-months. We used group-based trajectory modeling to determine characteristic trajectories of blackout frequency over 12-months in relation to baseline characteristics: demographics, substance use, delinquency, depression/anxiety symptoms, sexual assault, dating violence, and peer and sibling influences.

RESULTS

We identified four groups: No/Low blackouts (n = 248; 29.7%), Declining blackouts (n = 92; 11.0%), Moderate blackouts (n = 337; 40.3%) and High blackouts (n = 159; 19.0%); group membership did not differ based on intervention receipt. In adjusted analyses, compared to the No/Low group all other groups had higher odds of having an alcohol-related baseline ED visit. Female sex, alcohol consumption, prescription drug misuse, sexual assault while incapacitated due to substances, and negative peer influences were positively associated with membership in the High group; College/Greek life involvement was also highest. Negative peer influences and being in high school (vs. College/Greek life) also distinguished the Moderate group.

CONCLUSION

Blackout frequency was largely stable over time and riskier trajectories were marked by risk factors such as negative peer influences and college/Greek life involvement. Findings may inform targeted interventions, particularly for women who were in higher risk trajectories.

Replication of factors related to blackout incidence in U.S. high school students: A brief report

Alcohol-related blackouts are a common, yet serious consequence that can result from heavy alcohol intake. This study tested a model examining whether factors identified in related samples (i.e., adolescents residing in the U.K. and U.S. college students) predicted blackouts in community-dwelling U.S. high school youth. Participants from a Northeastern U.S. high school with prior alcohol use (M_age = 16.0 years; 48.2% male, 78.0% White) completed a paper-and-pencil assessment including measures of demographics, alcohol and other substance use, externalizing behaviors, and injunctive norms about risky drinking behaviors. Hierarchical logistic regression examined which factors identified for U.K. residing adolescents (Block 1) replicated in the U.S. sample, and whether factors identified in samples of U.S. college students added additional explained variance (Block 2). Blackouts were reported by 35.6% of students. Regression results indicated that two variables previously identified in adolescents, female gender (OR = 3.26) and increased alcohol use (OR = 1.27) were associated with blackouts. College student risk factors of drinking game (DG) participation and, to a lesser degree injunctive norms for passing out, emerged as additional risk factors (ORs = 2.85 and 1.32, respectively), with the final model explaining 39% of the variance in blackouts. This study advances our understanding of blackouts in younger drinkers and identifies the importance of addressing blackouts within the context of intervention programming that addresses cognitions and high risk drinking practices like DGs.

A Critical Review of Methods and Results in the Search for Genetic Contributors to Alcohol Sensitivity

Attributes of alcohol sensitivity are present before alcohol use disorders (AUDs) develop, they predict those adverse alcohol outcomes, are familial in nature, and many are heritable. Whether measured by alcohol challenges or retrospective reports of numbers of drinks required for effects, alcohol sensitivity reflects multiple phenotypes, including low levels of alcohol response and alcohol-related stimulation. Identification of genes that contribute to alcohol sensitivity could help identify individuals carrying risks for AUDs through their alcohol responses for whom early intervention might mitigate their vulnerability. Such genes could also improve understanding of biological underpinnings of AUDs, which could lead to new treatment approaches. However, the existing literature points to a wide range of genetic mechanisms that might contribute to alcohol responses, and few such genetic findings have been widely replicated. This critical review describes the potential impact of the diverse methods used to study sensitivity on the diversity of genetic findings that have been reported, places the genetic variants mentioned in the literature into broader categories rather than isolated results, and offers suggestions regarding how to advance the field by interpreting findings in light of the methods used to select research subjects and to measure alcohol sensitivity. To date, the most promising results have been for GABA, glutamate, opioid, dopamine, serotonin, and cholinergic system genes. The more gene variants that can be identified as contributors to sensitivity the better future gene screening platforms or polygenic scores are likely to be.

Alcohol-induced blackouts, subjective intoxication, and motivation to decrease drinking: Prospective examination of the transition out of college

OBJECTIVE

We prospectively examined whether subjective intoxication serves as a risk factor for experiencing alcohol-induced blackouts. We then examined whether subjective intoxication and/or blackouts predicted motivation to decrease their drinking, and whether this motivation to change would promote future changes in drinking behavior.

METHOD

Participants (N=1854, 62.1% female, 53.2% Caucasian, M_age=21.8) were recruited the summer prior to matriculating into a large, public university to complete a 6-year longitudinal study. Self-reported motivation to decrease their drinking behavior, their frequency of blackouts, quantity of alcohol consumption, and subjective intoxication (i.e., feeling drunk) were assessed annually during the transition out of college (Years 4-6).

RESULTS

In a cross-lagged model, subjective intoxication (i.e., feeling drunk) prospectively predicted experiencing blackouts (p<0.001). Controlling for both objective (e.g., quantity) and subjective intoxication, blackouts at Year 4 predicted greater motivation to decrease drinking behavior at Year 5 (p<0.01), but this motivation did not predict less quantity of alcohol use by Year 6 (p=0.076).

CONCLUSIONS

Subjective intoxication is a robust predictor of blackouts across time. Additionally, blackouts are modest, developmentally-limited predictors of motivation to change drinking behavior, but blackouts do not predict future behavior change.

Drinking Status Between Ages 50 and 55 for Men From the San Diego Prospective Study Who Developed DSM-IV Alcohol Abuse or Dependence in Prior Follow-Ups

OBJECTIVE

Although alcohol use disorders (AUDs) are prevalent among older individuals, few studies have examined the course and predictors of AUDs from their onset into the person's 50s. This study describes the AUD course from ages 50 to 55 in participants who developed AUDs according to criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), during the San Diego Prospective Study (SDPS).

METHOD

Among the 397 university students in the SDPS who were followed about every 5 years from age 20 (before AUD onset), 165 developed AUDs, 156 of whom were interviewed at age 55. Age 50-55 outcomes were compared regarding age 20-50 characteristics. Variables that differed significantly across outcome groups were evaluated using binary logistic regression analyses predicting each outcome type.

RESULTS

Between ages 50 and 55, 16% had low-risk drinking, 36% had high-risk drinking, 38% met DSM-5 AUD criteria, and 10% were abstinent. Baseline predictors of outcome at ages 50-55 included earlier low levels of response to alcohol predicting DSM-5 AUDs and abstinence, higher drinking frequency predicting DSM-5 diagnoses and lower predicting low-risk drinking, higher participation in treatment and/or self-help groups predicting abstinence and lower predicting DSM-5 AUDs, later ages of AUD onset predicting high-risk drinking, and cannabis use disorders predicting abstinent outcomes.

CONCLUSIONS

Despite the high functioning of these men, few were abstinent or maintained low-risk drinking during the recent 5 years, and 38% met DSM-5 AUD criteria. The data may be helpful to both clinicians and researchers predicting the future course of AUDs in their older patients and research participants.

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.

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.