Web-based treatment for substance use disorders: Differential effects by primary substance

Introduction: This secondary analysis of data from a large, multi-site effectiveness trial (NCT01104805) sought to determine whether effects of a web-based behavioral treatment (Therapeutic Education System [TES]) differed by participants' self-identified primary drug of abuse. Methods: The all-comers sample of individuals entering outpatient psychosocial counseling treatment for substance abuse (N = 497) cited cannabis (22.9%; n = 114), stimulants (34.4%, n = 171), opioids (21.7%, n = 108), or alcohol (20.9%, n = 104) as their primary substance of abuse. Participants were randomly assigned to receive treatment-as-usual (TAU) with or without TES substituted for approximately 2. h of usual counseling. Multivariate analyses of abstinence outcomes examined interactions of treatment effects with primary substance. Results: Adjusted odds ratios (AORs) demonstrated that primary stimulant users receiving TES were more likely to be abstinent in the final four weeks of treatment compared to stimulant users receiving TAU (AOR = 3.59, 95% CI = 1.25-10.27). Adjusted odds ratios for alcohol (AOR = 3.15, 95% CI = 0.85-11.65) and cannabis (AOR = 2.64, 95% CI = 0.73-9.52) also were of similar magnitude to stimulants but did not reach significance. Abstinence among primary opioid users was not improved by the TES intervention (AOR = 0.35, 95% CI = 0.09-1.47). Conclusions: This study supports the TES web-delivered treatment as a viable intervention for the majority of substance users entering outpatient counseling treatment, with demonstrated effectiveness among stimulant users and promising effects in alcohol and cannabis users but little or no effect in primary opioid users. Web-delivered treatments hold promise for expanding the availability of effective behavioral interventions for the majority of substance use disorders.