Effectiveness of acceptance and commitment therapy for addictive behaviors: A systematic review and meta-analysis

The use of acceptance and commitment therapy (ACT) has expanded in the field of addictive disorders in recent years. This systematic review and meta-analysis examined the effectiveness of ACT compared to other active interventions in terms of treatment completion, addiction-related outcomes, and changes in psychological flexibility. Searches were conducted in PsycINFO, PubMed, Scopus, and Web of Science. Four random-effects meta-analyses were conducted to assess the effectiveness of ACT in terms of completion rates and abstinence at the end of treatment (EOT), in the short term (≤6 months follow-up), and in the long term (>6-month follow-up). Participants’ sex and age, the number of ACT sessions, the characteristics of the experimental condition (i.e., ACT combined with pharmacological intervention or non-combined) and the comparison condition (i.e., ACT compared to cognitive-behavioral therapy [CBT] or non-CBT interventions), treatment modality (face-to-face or technology-based approaches), and the targeted addictive behavior were examined as moderators. A total of 28 studies were included in the systematic review and 22 in the meta-analysis. There were no differences in EOT completion rates (Log RR = 0.0038; 95% CI: −0.026, 0.034). ACT increased the odds of abstinence at EOT (Log RR = 0.264; 95% CI: 0.046, 0.482) and at short-term follow-up (Log RR = 0.295; 95% CI: 0.108, 0.483), but not in the long term (Log RR = 0.164; 95% CI: −0.101, 0.430). ACT demonstrated higher abstinence rates than CBT conditions at EOT (p = 0.002). A lower age increased abstinence rates in the short (p = 0.004) and long term (p < 0.001), whereas a greater number of ACT sessions increased long-term abstinence rates (p < 0.001). ACT is an effective approach for promoting short-term abstinence. In the long term, it is at least as effective as other empirically validated therapies, such as CBT. Further studies are needed to clarify the effects of increasing psychological flexibility on addictive behaviors.