Predictors of Daily Adherence to Naltrexone for Alcohol Use Disorder Treatment During a Mobile Health Intervention

Background Adherence to medications for treating alcohol use disorder (AUD) is poor. To identify predictors of daily naltrexone adherence over time, a secondary data analysis was conducted of a trial evaluating a mobile health intervention to improve adherence. Methods Participants seeking treatment for AUD (n = 58; M-age = 38 years; 71% male) were prescribed naltrexone for 8 weeks. Adherence was tracked using the Medication Event Monitoring System (MEMS). In response to daily text messages, participants reported the previous day's alcohol use, craving, and naltrexone side effects. Using multilevel structural equation modeling (MSEM), we examined baseline dispositional factors and within-person, time-varying factors as predictors of daily adherence. Results Naltrexone adherence decreased over time. Adherence was higher on days when individuals completed daily mobile assessments relative to days when they did not (odds ratio [OR] = 2.53, 95% confidence interval [CI] 1.61 to 3.98), irrespective of intervention condition. Days when individuals drank more than their typical amount were related to lower next-day adherence (OR = 0.93, 95% CI 0.88 to 0.99). A similar pattern was supported for craving (OR = 0.88, 95% CI 0.79 to 0.98). Weekend days were associated with lower adherence than weekdays (OR = 0.71, 95% CI 0.58 to 0.86); this effect was partly mediated by heavier daily drinking (indirect effect = -0.02, 95% CI -0.04 to -0.003) and stronger-than-usual craving (indirect effect = -0.01, 95% CI -0.02 to 0.00) on weekend days. Conclusions The results further demonstrate the need to improve adherence to AUD pharmacotherapy. The present findings also support developing interventions that target daily-level risk factors for nonadherence. Mobile health interventions may be one means of developing tailored and adaptive adherence interventions

Preprint: Mood and Implicit Alcohol Expectancy Processes: Predicting Alcohol Consumption in the Laboratory

Background—Implicit positive alcohol expectancy (PAEs) processes are thought to respond phasically to external and internal stimuli – including mood states – and so they may exert powerful proximal influences over drinking behavior. Although social learning theory contends that mood states activate mood-congruent implicit PAEs, which in turn lead to alcohol use, there is a dearth of experimental research examining this mediation model relative to observable drinking. Moreover, an expectancy theory perspective might suggest that, rather than influencing PAEs directly, mood may moderate the association between PAEs and drinking. To test these models, the present study examined the role of mood in the association between implicitly measured PAE processes (i.e., latency to endorse PAEs) and immediate alcohol consumption in the laboratory. Gender differences in these processes also were examined. Method—College students (N=146) were exposed to either a positive, negative, or neutral mood induction procedure, completed a computerized PAE reaction time (RT) task, and subsequently consumed alcohol ad libitum. Results—The mood manipulation had no direct effects on drinking in the lab, making the mediation hypothesis irrelevant. Instead, gender and mood condition moderated the association between RT to endorse PAEs and drinking in the lab. For males, RT to tension reduction PAEs was a stronger predictor of volume of beer consumed and peak BAC in the context of general arousal (i.e., positive and negative mood) relative to neutral mood. RT to PAEs did not predict drinking in the lab for females. Conclusions—The results show that PAE processes are important determinants of immediate drinking behavior in men, suggesting that biased attention to mood-relevant PAEs – as indicated by longer RTs – predicts greater alcohol consumption in the appropriate mood context. The findings also highlight the need to consider gender differences in PAE processes. This study underscores the need for interventions that target automatic cognitive processes related to alcohol use