Cognitive‐Behavioural Therapies for Young People in Outpatient Treatment for Non‐Opioid Drug Use: A Systematic Review

This Campbell systematic review examines the effects of cognitive behavioural therapy (CBT) when used in outpatient settings to reduce drug use (of e.g. cannabis, amphetamines, ecstasy, or cocaine) among young people aged 13‐21. The review summarizes findings from seven studies, all of which were randomised controlled trials. CBT is not any better at reducing the use of non‐opioid drugs among adolescents than other treatments when used in outpatient settings. The review is based on only a small number of studies, several of which show weaknesses and flaws in their methodology. There is a need to fund additional trials of CBT interventions, based on rigorous study designs and with a potential to add to the global CBT evidence base. The majority of included CBT studies were conducted in the U.S. The findings of this review may therefore only have limited applicability in other social and cultural settings. Future trials of CBT interventions should be conducted in a broader range of countries. Executive summary/Abstract BACKGROUND Youth drug use is a severe problem worldwide. This review focuses on Cognitive‐Behavioural Therapy (CBT) as a treatment for young people who misuse non‐opioid drugs, such as cannabis, amphetamines, ecstasy and cocaine, which are strongly associated with a range of health and social problems. CBT is an individualized and multicomponent intervention that combines behavioural and cognitive therapy. While behavioural therapy mainly focuses on external settings and observable behaviour, cognitive therapy is concerned with internal cognitive processes. The primary focus of CBT is to reduce users' positive expectations about drug use, to enhance their self‐confidence to resist drugs, and to improve their skills for problem‐solving and for coping with daily life stressors. OBJECTIVES The objective of this review is to assess the effectiveness of CBT for young people (aged 13‐21) in outpatient treatment for non‐opioid drug use and to explore any factors that may moderate outcomes. SEARCH STRATEGY An extensive search strategy was used to identify qualifying studies. A wide range of electronic bibliographic databases were searched along with government and policy databanks, grey literature databases, citations in other reviews and in the included primary studies, hand searches of relevant journals, and Internet searches using Google. We also corresponded with researchers in the CBT field. No language or date restrictions were applied to the searches. SELECTION CRITERIA Studies were required to meet several criteria to be eligible for inclusion. Studies must: have involved CBT treatment for young people aged 13‐21 years enrolled in outpatient treatment for non‐opioid drug use; have used experimental, quasi‐randomised or non‐randomised controlled designs; not have focused exclusively on treating mental disorders; and have had CBT as the primary intervention. DATA COLLECTION AND ANALYSIS The literature search yielded a total of 18,514 references, of which 394 were deemed potentially relevant and retrieved for eligibility determination. Of these, 360 did not fulfil the screening criteria and were excluded. Four records were unobtainable. A total of seven unique studies, reported in 17 papers, were included in the review. Meta‐analysis was used to examine the effects of CBT on drug use reduction, social and family functioning, school problems, treatment retention and criminal activity compared to a group of other interventions (Adolescent Community Reinforcement Approach (ACRA), Chestnut Bloomington Outpatient (CBOP) (+Assertive Continuing Care (ACC)), Drugs Harm Psychoeducation curriculum (DHPE), Functional Family Therapy (FFT), Interactional Therapy (IT), Multidimensional Family Therapy (MDFT), and Psychoeducational Therapy (PET)). RESULTS Our main objective was to evaluate the current evidence on the effect of CBT on abstinence and drug use reduction for young people in outpatient treatment for non‐opioid drug use. Seven randomised trials, involving 953 participants, were included in this review. Each of the seven included studies compared CBT to another intervention. We analysed the effects in the short term (from the start of treatment to up to 6 months thereafter), medium term (from 6 months to less than 12 months after the start of treatment), and long term (12 months or more after the start of treatment). We analysed CBT that was delivered with an add‐on component such as motivational interviewing (four studies) separately from CBT that was delivered without an add‐on component (three studies). Based on meta‐analysis of data from the four included studies analysing CBT with an add‐on component, there was no evidence of a relative effect of CBT for the reduction of youth drug use frequency compared to other interventions (ACRA, CBOP (+ACC), DHPE, FFT and MDFT). The random effects standardized mean difference was ‐0.14 (95% CI ‐0.64, 0.36) for the short term based on four studies, ‐0.06 (95% CI ‐0.44, 0.32) for the medium term based on four studies and ‐0.15 (95% CI ‐0.36, 0.06) for the long term based on two studies. Based on meta‐analysis of data from the four included studies analysing CBT without an add‐on component, there was no evidence of a relative effect of CBT for the reduction of youth drug use frequency compared to other interventions (IT, MDFT, and PET). The random effects standardized mean difference was ‐0.13 (95% CI ‐0.68, 0.42) for the short term based on two studies, ‐0.08 (95% CI ‐0.48, 0.31) for the medium term based on three studies and 0.02 (95% CI ‐0.48, 0.52) for the long term based on two studies. Thus, the available data does not support the hypothesis that there is a drug use reduction effect from using CBT with young drug users compared to other interventions (ACRA, CBOP (+ACC), DHPE, FFT, IT, MDFT, and PET). Statistically significant heterogeneity was present in the short term. In the medium term statistically significant heterogeneity was present between studies analysing CBT with an add‐on component. In the analysis of studies without an add‐on component there was no statistically significant heterogeneity in the medium term. Due to the low power of detecting heterogeneity with only two studies included in the analysis, this result should be interpreted with caution. There was no heterogeneity between studies in the long term; however, with only two studies included in the analyses the power to detect heterogeneity was low. The primary outcome measured as recovery could only be analysed in the long term. The meta‐analysis of CBT with an add‐on component was inconclusive as the eight different comparison combinations analysed showed different results. Only one study analysing CBT without an add‐on component provided data on recovery status. The reported effect was not statistically significant. Several sensitivity analyses were performed with respect to analysis method, risk of bias, and intervention characteristics. None of the results from these sensitivity analyses changed the overall conclusions. No statistically significant differences between CBT, with or without an add‐on component, and the comparison interventions (ACRA, CBOP (+ACC), DHPE, FFT, IT, MDFT, and PET) were found for the secondary outcomes of psychological problems, family problems, school problems, risk behaviour (related to crime) and retention. No studies reported on other adverse effects, such as suicide or overdoses. AUTHORS' CONCLUSIONS Based on the seven studies included in this review, there was no evidence that CBT interventions perform better or worse than the comparison interventions (ACRA, CBOP (+ACC), DHPE, FFT, IT, MDFT, and PET) with respect to reduction in young people's drug use. The evidence drawn from this systematic review is based on seven included studies analysed in two separate analyses, depending on whether the intervention was CBT with an add‐on component such as motivational interviewing (four studies) or CBT without an add‐on component (three studies). The seven studies are very different in terms of their findings regarding the effects of CBT interventions compared to other interventions (ACRA, CBOP (+ACC), DHPE, FFT, IT, MDFT, and PET) on young people's drug use. Therefore, the overall conclusion regarding the effect of CBT interventions compared to these other interventions on drug use reduction for young people aged 13 to 21 years should be interpreted with caution. The conclusions that can be drawn would be more convincing if more studies were available.