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

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.

A latent profile analysis of social anxiety, depression, and pregaming motives among heavy-drinking college students

BACKGROUND

Pregaming is a high-risk drinking behavior that is associated with heavy drinking and negative alcohol-related consequences. College students may engage in pregaming for several reasons, including to enhance social experiences or cope with negative affect. Research shows that associations between drinking, social anxiety, and depression are multifaceted. However, our understanding of the complex associations of mental health symptoms with pregaming motives and behaviors remains limited.

METHODS

This study examined heterogeneity in how pregaming motives, social anxiety, and depression associate with past 30-day pregaming variables (quantity, frequency, and negative consequences). We used latent profile analysis (LPA) in a sample of heavy-drinking university students (N = 479).

RESULTS

LPA results indicated four profiles: mild/moderate social anxiety and depression symptoms, moderate motives (n = 285), minimal social anxiety and depression symptoms, low motives (n = 61), subclinical/elevated social anxiety and depression symptoms, high motives (n = 75), and clinically elevated social anxiety and depression symptoms, moderate motives (n = 58). The subclinical/elevated symptoms, high motives profile reported the highest pregaming frequency and consequences, including blackouts. Individuals in the clinically elevated symptoms, moderate motives profile reported more consequences than those in the minimal symptoms, low motives and mild/moderate symptoms, moderate motives profiles. Individuals in the minimal symptoms, low motives profile reported the fewest consequences.

CONCLUSIONS

Among these students, social anxiety and pregaming motives were associated with more frequent pregaming and social anxiety and depression were associated with greater negative consequences. Interventions that target pregaming-specific motives among students with mental health symptoms may be warranted to reduce this risky behavior and associated drinking-related harm.

Does it really matter that I do not remember my night? Consequences related to blacking out among college student drinkers

BACKGROUND

Alcohol-induced blackouts (AIBs) are experienced frequently by college student drinkers and are more likely to occur on days with high-intensity drinking (HID; 8+ for females/10+ for males) than non-HID days. Research suggests that AIBs are associated with experiencing other alcohol-related consequences (ARCs), including more serious ARCs (SARCs; e.g., legal and sexual consequences), but we do not know whether individuals experience more ARCs and more SARCs on occasions when they black out than when they do not black out. This study examines the associations between AIBs and the total number of both ARCs and SARCs.

METHODS

Students (N = 462, 51.7% female, 87.7% White, Mage  = 20.1) were assessed across 6 weekends via e-surveys (80%-97% response rate). Multilevel models were used to test for main effects, controlling for drinking (HID or estimated blood alcohol concentration; eBAC) and sex.

RESULTS

Drinking days when an AIB was experienced were associated with more total ARCs (b = 3.54, 95% CI: 3.10, 3.99) and more SARCs (b = 0.77, 95% CI: 0.60, 0.95) per day than non-AIB days. The more frequently a person experienced an AIB, the more total ARCs (b = 5.33, 95% CI: 4.40, 6.25) and SARCs (1.05, 95% CI: 0.80, 1.30) they reported on average.

CONCLUSION

Alcohol-induced blackout days were associated with higher levels of harm than non-AIB days, even at the same levels of drinking. Interventions that focus on reducing the occurrence of AIBs and factors that contribute to them, in addition to reducing alcohol consumption, may help reduce total harm associated with drinking among college students.