What is the aim of this review?
The aim of this Cochrane Review was to determine whether mindfulness-based interventions (MBIs) i.e. interventions involving training in mindfulness meditation improve symptoms of substance use disorders (SUDs) (i.e. alcohol and/or drug use, but excluding tobacco use disorders). Cochrane researchers searched, selected and analyzed all relevant studies to answer this question. We found 40 randomized controlled trials,that assessed MBI as a treatment for SUDs.
SUD outcomes were monitored at different time points: directly following completion of the MBIs, and at follow-up time points, which ranged from 3 months to 10 months after the MBI ended. Relative to other interventions (standard of care, cognitive behavioral therapy (CBT), psychoeducation, support group, physical exercise, medication), MBIs may slightly reduce days with substance use, but it is very uncertain whether they reduce other SUD-related outcomes. The effects of MBIs relative to no treatment was very uncertain across all SUD-assessed outcomes, as was the risk for adverse events.
What was studied in this review?
SUDs are very common and associated with negative physical and psychological health outcomes. Although evidence-based interventions exist for treating SUDs, the standard treatments may not be sufficient and many individuals relapse to substance use. In the past several decades, MBIs have been examined for the treatment of SUDs. MBIs involve training in mindfulness meditation practice, which emphasizes the cultivation of present-moment, non-judgmental awareness. MBIs may improve many of the psychological variables involved in substance use and relapse (i.e. depression, anxiety, stress, attention). We studied whether MBIs benefit individuals with SUDs.
We searched for studies that compared an MBI to no treatment or to another treatment (e.g. cognitive behavior therapy, psychoeducation). We studied the results at the end of the intervention and at follow-up assessments, which occurred 3 to 10 months following the end of the intervention.
What are the main results of this review?
The review authors found 40 relevant studies, of which 45% were focused on individuals with various SUDs with the remaining studies including participants using a specific substance (e.g. alcohol, opioids). Of these 40 studies, 23 were conducted in the USA, 11 were conducted in Iran, two were conducted in Thailand, one was conducted in Brazil, one was conducted in China, one was conducted in Taiwan, and one was conducted in both Spain and the USA. We were able to analyze results of 35 studies composed of 2825 participants; the other five did not report usable results, and requests to the authors for more information were unsuccessful.
When MBIs were compared with other treatments, our review and analysis showed that MBIs may slightly reduce days with substance use at post-treatment and follow-up, and show similar study retention. The evidence is uncertain for other SUD-related outcomes we assessed (continuous abstinence, consumed amount, craving intensity). When MBIs were compared with no treatment, the evidence was uncertain for all SUD-related outcomes, although MBIs showed similar treatment retention. Adverse effects were only reported on in four studies. However, the available evidence did not suggest MBIs result in adverse events or serious adverse events.
How up-to-date is this review?
The review authors searched for studies published up to April 2021.
Study funding sources
Sixteen studies reported no funding. The remaining studies reported one or more sources of funding and support. Nineteen acknowledged federal sources, seven acknowledged internal grants, four acknowledged non-profit entities, and two acknowledged clinics.
In comparison with no treatment, the evidence is uncertain regarding the impact of MBIs on SUD-related outcomes. MBIs result in little to no higher attrition than no treatment. In comparison with other treatments, MBIs may slightly reduce days with substance use at post-treatment and follow-up (4 to 10 months). The evidence is uncertain regarding the impact of MBIs relative to other treatments on abstinence, consumed substance amount, or craving. MBIs result in little to no higher attrition than other treatments. Few studies reported adverse events.
Substance use disorders (SUDs) are highly prevalent and associated with a substantial public health burden. Although evidence-based interventions exist for treating SUDs, many individuals remain symptomatic despite treatment, and relapse is common.Mindfulness-based interventions (MBIs) have been examined for the treatment of SUDs, but available evidence is mixed.
To determine the effects of MBIs for SUDs in terms of substance use outcomes, craving and adverse events compared to standard care, further psychotherapeutic, psychosocial or pharmacological interventions, or instructions, waiting list and no treatment.
We searched the following databases up to April 2021: Cochrane Drugs and Alcohol Specialised Register, CENTRAL, PubMed, Embase, Web of Science, CINAHL and PsycINFO. We searched two trial registries and checked the reference lists of included studies for relevant randomized controlled trials (RCTs).
RCTs testing a MBI versus no treatment or another treatment in individuals with SUDs. SUDs included alcohol and/or drug use disorders but excluded tobacco use disorders. MBIs were defined as interventions including training in mindfulness meditation with repeated meditation practice. Studies in which SUDs were formally diagnosed as well as those merely demonstrating elevated SUD risk were eligible.
We used standard methodological procedures expected by Cochrane.
Forty RCTs met our inclusion criteria, with 35 RCTs involving 2825 participants eligible for meta-analysis. All studies were at high risk of performance bias and most were at high risk of detection bias.
Mindfulness-based interventions (MBIs) versus no treatment
Twenty-four RCTs included a comparison between MBI and no treatment. The evidence was uncertain about the effects of MBIs relative to no treatment on all primary outcomes: continuous abstinence rate (post: risk ratio (RR) = 0.96, 95% CI 0.44 to 2.14, 1 RCT, 112 participants; follow-up: RR = 1.04, 95% CI 0.54 to 2.01, 1 RCT, 112 participants); percentage of days with substance use (post-treatment: standardized mean difference (SMD) = 0.05, 95% CI -0.37 to 0.47, 4 RCTs, 248 participants; follow-up: SMD = 0.21, 95% CI -0.12 to 0.54, 3 RCTs, 167 participants); and consumed amount (post-treatment: SMD = 0.10, 95% CI -0.31 to 0.52, 3 RCTs, 221 participants; follow-up: SMD = 0.33, 95% CI 0.00 to 0.66, 2 RCTs, 142 participants). Evidence was uncertain for craving intensity and serious adverse events. Analysis of treatment acceptability indicated MBIs result in little to no increase in study attrition relative to no treatment (RR = 1.04, 95% CI 0.77 to 1.40, 21 RCTs, 1087 participants). Certainty of evidence for all other outcomes was very low due to imprecision, risk of bias, and/or inconsistency. Data were unavailable to evaluate adverse events.
Mindfulness-based interventions (MBIs) versus other treatments (standard of care, cognitive behavioral therapy, psychoeducation, support group, physical exercise, medication)
Nineteen RCTs included a comparison between MBI and another treatment. The evidence was very uncertain about the effects of MBIs relative to other treatments on continuous abstinence rate at post-treatment (RR = 0.80, 95% CI 0.45 to 1.44, 1 RCT, 286 participants) and follow-up (RR = 0.57, 95% CI 0.28 to 1.16, 1 RCT, 286 participants), and on consumed amount at post-treatment (SMD = -0.42, 95% CI -1.23 to 0.39, 1 RCT, 25 participants) due to imprecision and risk of bias. The evidence suggests that MBIs reduce percentage of days with substance use slightly relative to other treatments at post-treatment (SMD = -0.21, 95% CI -0.45 to 0.03, 5 RCTs, 523 participants) and follow-up (SMD = -0.39, 95% CI -0.96 to 0.17, 3 RCTs, 409 participants). The evidence was very uncertain about the effects of MBIs relative to other treatments on craving intensity due to imprecision and inconsistency. Analysis of treatment acceptability indicated MBIs result in little to no increase in attrition relative to other treatments (RR = 1.06, 95% CI 0.89 to 1.26, 14 RCTs, 1531 participants). Data were unavailable to evaluate adverse events.