Telephone monitoring and 15-month outcomes for patients with co-occurring substance use and mental health disorders: Moderating effects of high-risk patient characteristics

Introduction: Telephone monitoring interventions for substance use disorders are an important component of continuing care to reduce relapse and connect patients to services. However, a knowledge gap still exists as to which patient groups benefit most from them. This secondary analysis of a randomized controlled trial examined moderators of associations between telephone monitoring and 15-month substance use outcomes among patients with co-occurring substance use and mental health disorders. High-risk patient characteristics at baseline were examined as potential moderators of the effectivness of telephone monitoring, including history of incarceration, severity of depression symptoms, and suicide risk. Methods: Participants were 406 psychiatry inpatients with documented substance use and mental health disorders who were randomized to treatment as usual (TAU; n = 199) or TAU plus telephone monitoring (TM; n = 207). Outcomes included abstinence self-efficacy (Brief Situational Confidence Questionnaire) and alcohol and drug use severity (Addiction Severity Index composites) at 15-month follow-up. Analyses examined main effects of treatment condition and moderators, and interactions between treatment condition and moderators.Results: The study found five significant main effects, three of which were qualified by significant interactions. Incarceration history was associated with higher drug use severity; higher suicide risk was associated with higher abstinence self-efficacy. Regarding interaction effects, among participants with an incarceration history, TM compared to TAU was associated with significantly lower alcohol use severity at 15-month follow-up; this finding did not hold for never-incarcerated participants. For participants with less severe depression symptoms, TM compared to TAU was associated with significantly lower alcohol use severity and higher abstinence self-efficacy at follow-up; this did not hold for participants with more severe depression symptoms. Suicide risk was not a significant moderator of any outcome.Conclusions: Results indicate that TM is effective in improving alcohol use severity and abstinence self-efficacy for some subgroups of patients, including patients with an incarceration history or less severe depression. Results inform the clinical provision of substance use disorder care by means of telehealth, which increased due to the COVID-19 pandemic.