Efficacy of a personalised alcohol approach bias modification smartphone app in people accessing outpatient alcohol use disorder treatment: A randomised controlled trial.

BACKGROUND AND AIMS: Several randomised controlled trials (RCTs) have demonstrated that delivering approach bias modification (ApBM) during residential alcohol use disorder (AUD) treatment helps prevent post-treatment relapse. However, few studies have examined ApBM's efficacy for AUD in outpatients. We trialled a personalised ApBM smartphone app in individuals receiving outpatient AUD treatment.

DESIGN

This double-blind RCT randomised participants to receive ApBM or sham training, adjunctive to treatment as usual.

SETTING

Participants were recruited from alcohol and other drug treatment services in Melbourne, Australia.

PARTICIPANTS

79 participants (mean age 46.6 years; 45 male, 34 female) installed the app between May 2022 and January 2024.

INTERVENTION AND COMPARATOR: In the ApBM condition, the app delivered personalised, gamified ApBM. Notifications prompted participants (n = 39) to complete 2 ApBM sessions weekly for 4 weeks. The control version prompted participants (n = 40) to complete a weekly sham-training task for 4 weeks.

MEASUREMENTS: The primary outcome was number of standard drinks (10 g pure alcohol) consumed in week 4 of the intervention period, self-reported in the app. Secondary outcomes included past-week standard drinks at 8-week and 16-week follow-ups, past-week drinking days, past-week heavy drinking days (HDDs; days when ≥5 standard drinks were consumed) and questionnaire measures of AUD severity, quality of life and alcohol craving. Primary analyses followed an intention-to-treat (ITT) approach, with secondary complete-case sensitivity analyses also conducted for all outcomes.

FINDINGS: Groups did not statistically significantly differ in the primary outcome [values from ITT negative binomial model: ApBM = 75.49 standard drinks, control = 71.34 standard drinks, difference = 4.16, 95% confidence interval (CI) = -42.37 to 50.69, P = 0.859]. Most analyses of secondary outcomes showed statistically non-significant effects, with the only exception being past-week standard drinks at the 16-week follow-up, where ApBM participants showed statistically significantly larger decreases than controls in past-week standard drinks (reduction of 14.6, relative to baseline, versus 2.1 in controls; interaction β = -12.53, 95% CI = -23.85 to -1.22; P = 0.030). Time x group interaction effects were statistically non-significant for all other secondary outcomes (Ps > 0.069).

CONCLUSIONS

A smartphone app using approach bias modification showed no evidence for reducing alcohol use among alcohol use disorder outpatients after 4 weeks, or evidence for effects on most secondary outcomes, although 16-week follow-up results suggested that approach bias modification may have facilitated delayed/longer-term reductions in alcohol use.