A combined laboratory and field test of a smartphone breath alcohol device and blood alcohol concentration estimator to facilitate moderate drinking among young adults

Impaired Control (Both Attempts to Control Drinking and Failed Control) as Prospective Predictors of Negative Outcomes Among Young Adults Who Drink Heavily

OBJECTIVE

Impaired control over alcohol is a hallmark of addiction relevant to young adults, but additional prospective findings are needed, particularly in samples reporting heavy drinking. Further, we lack understanding of how attempts and failed efforts to control drinking relate to each other in predicting outcomes. We hypothesized that attempted and failed control would prospectively predict outcomes, with endorsement of both being especially problematic.

METHOD

We used data from young adults reporting heavy drinking who enrolled in laboratory alcohol self-administration studies (n = 109). Mixed-effects models were used to predict drinks per drinking day, heavy drinking, and negative consequences across baseline and 6- and 12-month follow-ups. Interactions by time and between attempted and failed control were tested.

RESULTS

Higher failed control was associated with steeper declines in consequences and heavy drinking over time compared with lower failed control. However, higher attempted or failed control was still associated with more consequences and alcohol use than lower impaired control at multiple time points. A significant interaction indicated that the combination of higher attempted and failed control was associated with the most drinks per drinking day. There was also a significant Attempted × Failed Control interaction for heavy drinking.

CONCLUSIONS

These findings provide further evidence supporting impaired control over alcohol use as a risk factor among young adults. Those reporting both higher attempted and failed control drank the most per day. Either attempted or failed control was associated with negative consequences. Those reporting both higher attempted and failed control may be in greatest need of intensive intervention.

A physiologically-based digital twin for alcohol consumption-predicting real-life drinking responses and long-term plasma PEth

Alcohol consumption is associated with a wide variety of preventable health complications and is a major risk factor for all-cause mortality in the age group 15-47 years. To reduce dangerous drinking behavior, eHealth applications have shown promise. A particularly interesting potential lies in the combination of eHealth apps with mathematical models. However, existing mathematical models do not consider real-life situations, such as combined intake of meals and beverages, and do not connect drinking to clinical markers, such as phosphatidylethanol (PEth). Herein, we present such a model which can simulate real-life situations and connect drinking to long-term markers. The new model can accurately describe both estimation data according to a χ2 -test (187.0 < Tχ2 = 226.4) and independent validation data (70.8 < Tχ2 = 93.5). The model can also be personalized using anthropometric data from a specific individual and can thus be used as a physiologically-based digital twin. This twin is also able to connect short-term consumption of alcohol to the long-term dynamics of PEth levels in the blood, a clinical biomarker of alcohol consumption. Here we illustrate how connecting short-term consumption to long-term markers allows for a new way to determine patient alcohol consumption from measured PEth levels. An additional use case of the twin could include the combined evaluation of patient-reported AUDIT forms and measured PEth levels. Finally, we integrated the new model into an eHealth application, which could help guide individual users or clinicians to help reduce dangerous drinking.

Initial evidence of delay discounting's predictive utility for alcohol self-administration in ecologically valid contexts among young adults who drink heavily

BACKGROUND

While delay discounting is robustly associated with alcohol use disorder, whether discounting predicts real-time alcohol use behaviors is unclear. Existing support comes from laboratory studies using intravenous alcohol self-administration methods, thus limiting ecological validity and generalizability. The present study evaluated whether delay discounting predicted real-time alcohol use in naturalistic settings with and without probabilistic negative consequences for consuming larger amounts of alcohol.

METHODS

This secondary analysis utilized data from three laboratory alcohol self-administration studies with young adults who engaged in frequent heavy drinking (N=206, 45% female). Participants completed a delay discounting measure before an alcohol self-administration session in an actual or simulated bar with (n=187) or without (n=19) probabilistic negative consequences (compensation loss) tied to performance on cognitive and psychomotor tasks after alcohol self-administration. Bootstrapped (unstandardized) coefficient estimates and 95% confidence intervals were utilized due to the sample size discrepancy.

RESULTS

Multiple regressions revealed that delay discounting did not significantly predict estimated blood alcohol concentration (eBAC) or number of drinks consumed when procedures included probabilistic negative consequences. Among participants who completed procedures without probabilistic negative consequences, delay discounting was positively associated with peak eBAC.

CONCLUSION

Counter to hypotheses, steeper delay discounting did not predict real-time alcohol use in contexts with probabilistic negative consequences, whereas preliminary evidence suggests that delay discounting predicts real-time alcohol use behaviors in contexts without probabilistic negative consequences. The specific discounting task may have impacted study findings, thus future research should consider how the sign (gain vs. loss), outcome certainty, and delay relate to alcohol consumption.

Using mobile technology to influence alcohol-impaired driving risk perceptions and decisions

OBJECTIVE

Despite significant individual and societal risk, alcohol-impaired driving (AID) remains prevalent in the United States. Our aim was to determine whether breathalyzer-cued warning messages administered via mobile devices in the natural drinking environment could influence real-world AID cognitions and behaviors.

METHOD

One hundred twenty young adults (53% women; mean age = 24.7) completed 6 weeks of ecological momentary assessment (EMA) and provided breathalyzer samples using a BACtrack Mobile Pro linked to their mobile device. On mornings after drinking episodes, participants reported their driving activities from the previous evening (787 episodes). Participants were randomly assigned to receive warning messages if they reached a breath alcohol concentration (BrAC) ≥ .05, or no messages. Participants in the warnings condition reported their willingness to drive and perceived danger of driving at EMA prompts (1,541 reports).

RESULTS

We observed a significant effect of condition, such that the association between cumulative AID engagement and driving after reaching a BrAC of .05 was dampened among individuals in the warnings condition, compared to those in the no warnings condition. Receiving a warning message was associated with increased momentary perceived danger of driving and decreased willingness to drive.

CONCLUSIONS

We found that BrAC-cued warning messages reduced the probability of AID and willingness to drive while impaired, and increased the perceived danger of driving after drinking. These results serve as proof-of-concept for the use of mobile technology to deliver an adaptive just-in-time intervention to reduce the probability of AID. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Sleep and circadian influences on blood alcohol concentration

STUDY OBJECTIVES

Anecdotally, adults reach higher levels of subjective intoxication on days they are fatigued or sleep-deprived, but sleep is not typically discussed as a predictor of blood alcohol concentration (BAC) in clinical settings. To inform clinical work and future research, this perspective reviews data examining the impact of sleep (process S) and circadian (process C) factors on indicators of BAC in humans and animal models.

METHODS

Literature searches of medical and psychological databases were conducted to identify articles that manipulated sleep/circadian factors and reported effects on indicators of alcohol pharmacology (e.g. BAC, alcohol metabolism).

RESULTS

Of the 86 full-text articles reviewed, 21 met inclusion criteria. Studies included manipulations of time of day, circadian phase (evidence for process C), and time in bed (evidence for process S). Evidence for time-of-day effects on alcohol pharmacology was most compelling. Studies also provided evidence for circadian phase effects, but failed to find support for time-in-bed effects. Although results were not uniform across studies, most evidence from human and animal models indicates that peak BACs occur toward the beginning of the biological day, with some studies indicating slower alcohol elimination rates at this time.

CONCLUSIONS

Circadian factors likely influence alcohol pharmacokinetics, perhaps due to altered elimination of alcohol from the body. This means that individuals may reach higher BACs if they drink during the morning (when, for most people, circadian alerting is low) versus other times of the day. Alcohol prevention and intervention efforts should highlight sleep/circadian health as a potential contributor to alcohol-related harm.

Effect of typical alcohol use and expectancies on the social manipulation of drinking behavior in a virtual bar pilot study

BACKGROUND

Recent work indicates that increasing the drinking rate of a virtual bar-goer (VB) increases the rate of drinking for participants in a virtual reality (VR) bar environment. Here, we test the hypothesis that biopsychosocial factors including typical drinking pattern and expectancy that alcohol enhances social interactions would moderate this effect.

METHODS

We assessed the drinking topography (DT) of participants (N=20) in a VR environment with a programmable VB during two testing sessions: one with a fast-drinking VB (30-60s sip interval) and one in which the VB drank slowly (60-120s sip interval). In this secondary analysis, linear mixed models were used to characterize potential interactions of typical daily alcohol intake (quantity-frequency index [QFI]), maximal alcohol consumed in one bout over the past six months (maxQ), Alcohol Use Disorder Identification Test (AUDIT) score, and expectancy that alcohol enhances social and physical pleasures (SPP) with time in simulation and condition on sip interval and volume.

RESULTS

Individuals with higher MaxQ showed a reduced effect of time on sip volume such that more intense recent binge episodes were associated with consistent drinking. Greater AUDIT scores were associated with lower sip intervals. In addition, greater SPP expectancy was associated with higher sip volumes, but only in the fast-drinking VB condition.

CONCLUSIONS

Greater drinking behavior and social expectancies were associated with more rapid drinking topography. In addition, findings suggest challenging alcohol outcome expectancies related to social enhancement could reduce alcohol-related risks by slowing the rate of alcohol intake in social situations.

Psychological distance intervention reminders reduce alcohol consumption frequency in daily life

Modifying behaviors, such as alcohol consumption, is difficult. Creating psychological distance between unhealthy triggers and one's present experience can encourage change. Using two multisite, randomized experiments, we examine whether theory-driven strategies to create psychological distance-mindfulness and perspective-taking-can change drinking behaviors among young adults without alcohol dependence via a 28-day smartphone intervention (Study 1, N = 108 participants, 5492 observations; Study 2, N = 218 participants, 9994 observations). Study 2 presents a close replication with a fully remote delivery during the COVID-19 pandemic. During weeks when they received twice-a-day intervention reminders, individuals in the distancing interventions reported drinking less frequently than on control weeks-directionally in Study 1, and significantly in Study 2. Intervention reminders reduced drinking frequency but did not impact amount. We find that smartphone-based mindfulness and perspective-taking interventions, aimed to create psychological distance, can change behavior. This approach requires repeated reminders, which can be delivered via smartphones.