Assessment of Co-Occurring Substance Use During Opiate Treatment Programs in the United States

The effectiveness of opiate treatment programs (OTPs) can be significantly influenced by co-occurring substance use, yet there are no standardized guidelines for assessing the influence of co-occurring substance use on treatment outcomes. In this review, we aim to provide an overview on the status of the assessment of co-occurring substance use during participation in OTPs in the United States. We searched 4 databases-MEDLINE/PubMed, EMBASE, PsychINFO, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL)-from database inception to November 2018 to select relevant publications on OTPs that assessed participants' co-occurring substance use. We used a standardized protocol to extract study, intervention, and co-occurring substance use characteristics. Methodological quality was assessed using the Quality in Prognosis Studies tool. Of the 3,219 titles screened, 614 abstracts and 191 full-text original publications were assessed, leaving 85 eligible articles. Co-occurring substance use was most often assessed during opioid treatments using combined (pharmacological and behavioral) (n = 57 studies) and pharmacological (n = 25 studies) interventions. Cocaine, alcohol, marijuana, and benzodiazepines were frequently measured, while amphetamines and tobacco were rarely assessed. Great variation existed between studies in the timing and measurement of co-occurring substance use, as well as definitions for substances and polysubstance/polydrug use. Inconsistencies in the investigation of co-occurring substance use make comparison of results across studies challenging. Standardized measures and consensus on research on co-occurring substance use is needed to produce the evidence required to develop personalized treatment programs for persons using multiple substances and to inform best-practice guidelines for addressing polydrug use during participation in OTPs.