Abstract: Three studies are new to this update, resulting in five included studies in total (278 participants). Participants were primarily women (mean age 49.63 years, SD = 11.74) with different chronic pain conditions. We judged the studies too heterogeneous to pool data in a meta-analysis, so we have summarised the results from each study qualitatively. The studies included acupuncture, mindfulness, and cognitive behavioral therapy interventions aimed at reducing opioid consumption, misuse of opioids, or maintenance of chronic pain management treatments. We found mixed results from the studies. Three of the five studies reported opioid consumption at post-treatment and follow-up. Two studies that delivered 'Mindfulness-Oriented Recovery Enhancement' or 'Therapeutic Interactive Voice Response' found a significant difference between groups at post-treatment and follow-up in opioid consumption. The remaining study found reduction in opioid consumption in both treatment and control groups, and between-group differences were not significant. Three studies reported adverse events related to the study and two studies did not have study-related adverse events. We also found mixed findings for pain intensity and physical functioning. The interventions did not show between-group differences for psychological functioning across all studies. Overall, the risk of bias was mixed across studies. All studies included sample sizes of fewer than 100 and so we judged all studies as high risk of bias for that category. There is no evidence for the efficacy or safety of methods for reducing prescribed opioid use in chronic pain. There is a small number of randomised controlled trials investigating opioid reduction, which means our conclusions are limited regarding the benefit of psychological, pharmacological, or other types of interventions for people with chronic pain trying to reduce their opioid consumption. The findings to date are mixed: there were reductions in opioid consumption after intervention, and often in control groups too.

Plain-language summary: We searched for studies up to January 2017. We found five studies, and they investigated 278 people. Most people included in the studies were women, who were around 50 years of age, and reported a mixture of chronic pain conditions (e.g. headache, back pain, muscle pain). The studies included acupuncture, mindfulness, and cognitive behavioral therapy as strategies to decrease the amount of opioids taken by adults with chronic pain. No conclusions can be drawn from this small amount of information. Therefore, it is not clear whether these treatments decrease the amount of opioids in adults with chronic pain (primary outcome) or reduce pain intensity, physical ability or mood (secondary outcomes). Three studies did include negative effects of their treatment, and two reported that the participants did not have anything negative happen to them because of the trial they were in. Non-randomised studies, not included in this review, do indicate that for many people intensive rehabilitation packages may bring about major reduction in opioid use. Reducing prescribed opioid use in chronic non-cancer pain is an important topic in need of more systematic research. We were not able to judge the quality of evidence included in this review because the studies were so different and could not be combined.