Daily-level analysis of drinking intensity and acute physical consequences

Transdermal alcohol concentration features predict alcohol-induced blackouts in college students

BACKGROUND

Alcohol-induced blackouts (AIBs) are common in college students. Individuals with AIBs also experience acute and chronic alcohol-related consequences. Research suggests that how students drink is an important predictor of AIBs. We used transdermal alcohol concentration (TAC) sensors to measure biomarkers of increasing alcohol intoxication (rise rate, peak, and rise duration) in a sample of college students. We hypothesized that the TAC biomarkers would be positively associated with AIBs.

METHODS

Students were eligible to participate if they were aged 18-22 years, in their second or third year of college, reported drinking 4+ drinks on a typical Friday or Saturday, experienced ≥1 AIB in the past semester, owned an iPhone, and were willing to wear a sensor for 3 days each weekend. Students (N = 79, 55.7% female, 86.1% White, Mage = 20.1) wore TAC sensors and completed daily diaries over four consecutive weekends (89.9% completion rate). AIBs were assessed using the Alcohol-Induced Blackout Measure-2. Logistic multilevel models were conducted to test for main effects.

RESULTS

Days with faster TAC rise rates (OR = 2.69, 95% CI: 1.56, 5.90), higher peak TACs (OR = 2.93, 95% CI: 1.64, 7.11), and longer rise TAC durations (OR = 4.16, 95% CI: 2.08, 10.62) were associated with greater odds of experiencing an AIB.

CONCLUSIONS

In a sample of "risky" drinking college students, three TAC drinking features identified as being related to rising intoxication independently predicted the risk for daily AIBs. Our findings suggest that considering how an individual drinks (assessed using TAC biomarkers), rather than quantity alone, is important for assessing risk and has implications for efforts to reduce risk. Not only is speed of intoxication important for predicting AIBs, but the height of the peak intoxication and the time spent reaching the peak are important predictors, each with different implications for prevention.

Short-term changes in social role statuses across young adulthood and their relation to heavy drinking in a given month

Young adulthood is a developmental period during which individuals experience shifts in their social roles in various domains, which coincides with a period of time that is also high risk for lifetime peaks in alcohol use. The current study examined age-related changes in heavy episodic drinking (HED) and high-intensity drinking (HID) and associations with short-term (i.e., monthly) variation in young adults' social roles over a 2.5-year period in a community sample of young adults who reported past-year alcohol use (N = 778, baseline age range 18-23). Results showed probabilities of past-month HED and HID changed in a nonlinear fashion across ages 18-26 with greater probabilities of use at younger ages. Most participants did not report being in the same social role status every sampled month, underscoring the presence of short-term role variation. Living with parents and being in a serious romantic relationship in a given month were negatively associated with past-month HED. Living with parents in a given month was also negatively associated with past-month HID. Being a 4-year college student and being employed full-time in a given month were not significantly related to either outcome. Findings provided partial evidence that monthly statuses were associated with heavy drinking. Several avenues for future research are described in light of the findings.

Negative consequences associated with daily alcohol use as a nonlinear function of number of drinks in a daily diary study

INTRODUCTION

Drinking intensity among young adults is associated with greater negative alcohol-related consequences, but often studied using categorical drinking thresholds. This study examined how alcohol-related consequences varied as a continuous function of number of drinks consumed, without imposing thresholds, to identify drink ranges for which risk is greatest.

METHODS

Analyses included daily surveys from the Young Adult Daily Life study (2019-22) in which individuals reported drinking 1 or more alcoholic drinks (n=5219 days; 832 individuals). Time-varying effect models estimated total number of negative alcohol-related consequences and five individual consequences (hangover, drank more than planned, nausea/vomiting, did something embarrassing, blacked out) as a function of the number of drinks consumed among young adult males and females.

RESULTS

Often, increases in the number and prevalence of negative consequences were a nonlinear function of the number of drinks consumed. Females reported few negative consequences on 1-to-3-drink occasions but steep increases in consequences on 4-to-9-drink occasions. Among females, the prevalence of blacking out increased six-fold from 4-drink (3.4%; 95% CI=2.6,4.7) to 9-drink occasions (20.6%; 95% CI=16.1,26.1). Among males, the prevalence of some consequences, while not linear, increased across the full drink range. Blacking out among males increased from 9.6% (95% CI=6.2,14.7) on 10-drink occasions to 23.9% (95% CI=15.0,35.8) on 15-drink occasions.

CONCLUSIONS

Substantial heterogeneity is missed when typical drinking categories are used. In particular, variability in consequences across levels of the traditional binge drinking category suggests that important differences in risk may be missed when assessed as a uniform category.

A social media intervention for high-intensity drinking among emerging adults: a pilot randomized controlled trial

AIMS

High-intensity drinking (HID) is a pattern of risky drinking defined as at least 8 drinks (for women) or 10 drinks (for men) in a single episode. Individuals engaged in HID may be at greater risk for consequences, necessitating tailored interventions. Herein, we report the feasibility and acceptability of a social media-delivered 8-week intervention for emerging adults with recent HID.

METHODS

Using social media advertising, we recruited 102 emerging adults who reported past-month HID. Average age was 20.0 year-olds (SD = 2.0); 51.0% were male. Most identified as White (64.7%; 14.7% Black/African American, 13.7% multiracial) and 26.5% identified as Hispanic/Latinx. Participants were randomized to an 8-week intervention delivered via Snapchat by health coaches (N = 50) or to a control condition (psychoeducational website referral; N = 52). Follow-ups occurred at 2 and 4 months post-baseline.

RESULTS

The intervention was acceptable (85.1% liked it/liked it a lot) and there were high follow-up rates. Participants rated coaches as supportive (91.5%) and respectful (93.6%). Descriptively, helpfulness ratings were higher for non-alcohol-related content (e.g. stress; 59.6% very/extremely helpful) than alcohol-related content (40.4% very/extremely helpful). Regarding engagement, 86.0% engaged approximately weekly and 59.6% indicated they saved intervention snaps. Descriptive data showed reductions over time in several measures of alcohol consumption and consequences as well as cannabis-impaired driving and mental health symptoms.

CONCLUSIONS

This 8-week social media intervention for HID was feasible and acceptable among emerging adults, supporting the benefit of future testing in a fully powered trial.

High-intensity drinking and hours spent drinking

BACKGROUND

High-intensity drinking (HID) is associated with negative consequences, but it remains unclear whether a time qualifier (i.e., time spent drinking) is needed to identify individuals at highest risk. To improve the measurement and conceptualization of HID, we examined the utility of adding a time qualifier to define what constitutes an occasion of HID using repeated daily surveys in a sample of young adults.

METHODS

Participants were selected from a nationally representative sample of 12th-grade students in the United States who participated in the Monitoring the Future (MTF) study in Spring 2018. In 2019 and 2020, young adults (at modal ages 19-20) responded to annual and daily (14 consecutive days per year) online surveys about their alcohol use.

RESULTS

When we compared moderate drinking days (less than 4/5 drinks for women/men), binge drinking days (4-7/5-9 drinks), and HID days (8+/10+ drinks), HID days had the longest duration of drinking (5.2 h), highest peak estimated blood alcohol concentration (eBAC, 0.30%), and greatest drinking pace (2.58 drinks/h). HID was associated with a greater number of negative consequences than either moderate or binge drinking; adjusting for time spent drinking did not impact this interpretation. HID was reported on 10.9% of days; when defined as 8/10+ drinks in 4 h or 2 h, HID was reported on 4.8% and 1.0% of days, respectively. Nearly all differences in eBAC and negative consequences persisted across drinking intensity despite the introduction of time constraints.

CONCLUSIONS

HID days were characterized by both a longer time spent drinking and a more rapid pace of drinking. Adding a time qualifier to the definition of HID would restrict variability by only describing the minority of days and does not improve the distinctions among levels of risk.

Alcohol-induced blackouts among college student drinkers: A multilevel analysis

OBJECTIVE

To identify factors (manner of drinking, combined alcohol and other substance use, physiology) that are associated with alcohol-induced blackouts (AIBs) over and above estimated blood alcohol concentration (eBAC).

METHODS

Students (N = 462, 51.7 % female, 87.7 % White, M_age = 20.1) were assessed across 6 weekends via e-surveys (80-97 % response rate). eBAC was calculated using standard number of drinks, drinking duration, sex, and weight. Three-level multilevel models (days, weeks, persons) were conducted to test for main effects, controlling for eBAC.

RESULTS

Protective behavioral strategies (PBS) were associated with decreased odds of AIBs on the daily (OR = 0.64, 95 % CI: 0.53, 0.77), weekly (OR = 0.84, 95 % CI: 0.72, 0.98), and person-levels (OR = 0.62, 95 % CI: 0.51, 0.74). Combined cannabis with alcohol was associated with increased odds of AIBs on the weekly (OR = 2.13, 95 % CI 1.13, 4.07) and person-levels (OR = 3.56, 95 % CI 1.60, 7.93). People who more frequently played drinking games (OR = 1.41, 95 % CI: 1.12, 1.77), pregamed (OR = 1.55, 95 % CI: 1.19, 2.03), and showed higher tolerance (OR = 1.22, 95 % CI: 1.08, 1.37) showed increased risk of AIBs, over and above eBAC levels.

CONCLUSION

We identified a number of daily-, weekly-, and person-level factors that uniquely contribute to the prediction of AIBs even at equivalent eBACs. Many of these factors were behavioral, suggesting that they may serve as malleable prevention targets for AIBs in college student drinkers.

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.

Alcohol induces apoptosis and autophagy in microglia BV-2 cells

Alcohol (ethanol) has proven to be toxic to nearly all organs, with the brain being one of the principal targets. As one of the important components of the brain's blood-brain barrier (BBB) and central nervous system, the state of microglia may be associated with some symptoms of alcohol intoxication. In the present study, microglia BV-2 cells were exposed to various concentrations of alcohol for 3 or 12 h, imitating different stages of drunkenness after alcohol use, respectively. From the perspective of the autophagy-phagocytosis axis, our findings show that alcohol alters autophagy levels or promotes apoptosis in BV-2 cells. The current study adds to the understanding of the action mechanisms of alcohol neurotoxicity. We anticipate that this study will increase public awareness of alcohol's negative effects and contribute to the creation of novel alcoholism treatment approaches.

Initiation of and Escalation to High-Intensity Drinking in Young Adults

Importance

High-intensity drinking (HID) (≥10 drinks in a row) is associated with acute negative outcomes. Identifying factors associated with HID initiation in adolescence and how it is associated with young adulthood outcomes can inform screening and prevention.

Objective

To identify when individuals initiate HID and speed of escalation from first drink and first binge to first HID; characteristics associated with initiation and escalation; and whether these characteristics are associated with weekly alcohol consumption, HID frequency, and symptoms of alcohol use disorder at age 20 years.

Design, Setting, and Participants

This cohort study analyzed web-based survey data from respondents in the US who reported alcohol use in the past 30 days recruited from the 2018 12th grade Monitoring the Future study and surveyed again from February 14 through April 17, 2020, at modal age 20 years in the Young Adult Daily Life Study. Only respondents who reported HID by modal age 20 years were included in the analyses.

Exposures

Retrospective alcohol use initiation and self-reported alcohol use measures.

Main Outcomes and Measures

Key retrospective measures included year of initiation for alcohol, first binge (≥5 drinks), and HID (≥10 drinks). Measures at age 20 years included weekly alcohol consumption, HID frequency, and Alcohol Use Disorders Identification Test (AUDIT) scores. Covariates included biologic sex, race and ethnicity, parental college education, family history of alcohol problems, and college status. Descriptive statistics and multivariable regression models were used, and all analyses were weighted.

Results

Of the 451 participants with data eligible for analysis, 62.0% were male (38.0% female). On average, alcohol, binge, and HID were initiated during high school. Mean time of escalation from first drink to first HID was 1.9 (95% CI, 1.8-2.1) years and between first binge and first HID, 0.7 (95% CI, 0.6-0.8) years. Initiating HID by grade 11 (vs later) was associated with higher average weekly alcohol consumption (adjusted incidence rate ratio [aIRR], 1.40; 95% CI, 1.10-1.79]), HID frequency (aIRR, 2.01; 95% CI, 1.25-3.22]), and AUDIT score (adjusted odds ratio, 1.17; 95% CI, 1.02-1.34]) at age 20 years. Escalation from first binge to first HID in the same year (vs ≥1 year) was associated with higher HID frequency at age 20 years (aIRR, 1.66; 95% CI, 1.06-2.61).

Conclusions and Relevance

These findings suggest that understanding ages and patterns of HID initiation and escalation associated with particular risk may facilitate screening for adolescents and young adults.

Insomnia as a moderator of alcohol use and blackout: Potential role in acute physiological consequences

BACKGROUND

Alcohol-induced blackout is associated concurrently and prospectively with alcohol-related harm, including emergency room visits and sexual coercion. Although sleep has not been linked empirically to blackout, symptoms of insomnia have also been linked to memory impairment, in which case insomnia symptoms may compound alcohol's negative effects on memory. This study tested insomnia symptoms as a moderator of the association between heavy drinking and alcohol-induced blackout.

METHODS

Heavy-drinking young adults in college (N = 461, 69% female) completed assessments online from remote locations. Hierarchical linear regression was used to test a moderation model predicting blackout frequency. Logistic regression was used to test post hoc hypotheses.

RESULTS

In contrast to our main hypothesis, heavy drinking was more weakly (not more strongly) associated with blackout in the context of more severe insomnia. Post hoc analyses tested insomnia symptoms as a unique moderator of the association between heavy drinking and likelihood of acute physiological consequences of alcohol use (blackout, passing out, nausea/throwing up, and hangover). Insomnia severity at least marginally moderated the association between heavy drinking and 4 out of 5 physiological consequences of alcohol use, and only moderated the association between drinking and 1 of 19 remaining consequences.

CONCLUSIONS

Symptoms of insomnia are associated with alcohol-related harm, but may buffer associations between drinking and acute physiological consequences of alcohol. Additional research is needed to determine if alcohol heightens sensitivity to the acute physiological effects of alcohol, in which case less alcohol may be required for young adults with insomnia to experience these effects.