Abstract

Background

     While Cognitive Behavioral Therapy (CBT) is recommended as first-line treatment for depression, a significant minority do not show an adequate treatment response. Despite evidence for the efficacy of Mindfulness-Based Therapies (MBT) both in treating current depression and preventing relapse, it remains unknown whether MBT and CBT are equivalent in the treatment of current depression.

Methods

     Five databases were searched for randomized controlled trials (RCTs) directly comparing MBT with CBT and including depression as primary or secondary outcome.

Results

     When pooling the results of 30 independent RCTs with a total of 2750 participants, MBT and CBT were statistically significantly equivalent at both post-intervention (Hedges’s g = −۰٫۰۰۹; p < .001) and follow-up (g = −۰٫۰۳۳; p = .001). Supplementary Bayesian analyses provided further support for the alternative hypothesis of no difference between MBT and CBT. When exploring possible sources of heterogeneity, the differences at follow-up were smaller between CBT and mindfulness-based cognitive therapy (MBCT) than between CBT and mindfulness-based stress-reduction (MBSR) (Slope = 0.37;p = .022).

Conclusion

     The currently available evidence suggests that that MBT and CBT are equally efficacious in treating current adult depression. It remains unclear whether the similar effects of the two intervention types are due to different mechanisms or common factors.

Introduction

     Depression is one of the most common mental disorders worldwide, and it is estimated that around 280 million people suffer from depression at any time (World Health Organization, 2021). Depression affects not only the depressed individual and his or her immediate family but also has consequences for society at large (Lépine & Briley, 2011). Due to impaired functioning and early mortality, depression is an economic burden in terms of reduced or lost work and increased use of health care services (Lépine & Briley, 2011; P. S. Wang, Simon, & Kessler, 2003). The World_Health_Organization (2021) considers depression to be a substantial contributor to global disability, confirming the severe negative impact of depression.

     Cognitive-behavioral therapy (CBT) has proven efficacious in the treatment of depression (e.g., Butler, Chapman, Forman, & Beck, 2006; Cuijpers et al., 2013) and is recommended as a first-line psychological treatment for depression (American Psychological Association, 2019; The_National_Institute_for_Health_and_Care_Excellence, 2009). However, many patients relapse or continue to show residual symptoms (Paykel, 2007; Thase et al., 1992; Vittengl, Clark, Dunn, & Jarrett, 2007) or continue to experience residual symptoms (Taylor, Walters, Vittengl, Krebaum, & Jarrett, 2010). During the last two decades, mindfulness-based therapies (MBT) have received increased attention as possible interventions for depression, and the results of several meta-analyses provide support for the efficacy of MBT in treating current adult depression, e.g. (Goldberg et al., 2018; Khoury et al., 2013; Y.-Y. Wang et al., 2018). Mindfulness has been defined as \the awareness that emerges through paying attention on purpose, in the present moment, and nonjudgmentally to the unfolding of experience moment by moment” (J. Kabat-Zinn, 2003). The two most investigated MBTs are mindfulness-based stress reduction (MBSR) (Kabat-Zinn, 1990) and mindfulness-based cognitive therapy (MBCT) (Segal, Williams, & Teasdale, 2012). Both teach mindfulness meditation techniques to help individuals become aware of their thoughts, feelings, and bodily sensations in the present moment and to subsequently help them change how they relate to these experiences. The MBSR program was developed for people with chronic illnesses and stress-related disorders, and is an eight-week course consisting of eight weekly 2.5-h group sessions and a silent retreat day, with focus on systematic training in mindfulness (Kabat-Zinn, 1990). In addition, the participants engage in home practice between sessions, including both formal (e.g., body scan) and informal practice (e.g., mindful awareness to everyday activities).

Conclusion

     Taken together, the present study fills a gap in the literature by systematically reviewing RCTs that have directly compared the efficacy of MBT and CBT for adult depression and by conducting a meta-analysis of equivalence showing not only that MBT and CBT did not differ in their effects but also that they were statistically significantly equivalent. While the results of the available studies do not allow a conclusion that the effects of the two therapies stem from common factors, the equivalent efficacy of MBT and CBT in treating depression opens up for increased flexibility in the choice of treatment.

Role of funding sources

     TrygFonden (Denmark), grant number: 7-12.0736, funded EN. The remaining authors did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors for this research.