Acceptance and Commitment Therapy, a Mindfulness-Based Approach for Treatment of Chronic Musculoskeletal Pain
Condition: Chronic Musculoskeletal Disease
MeSH terms: Musculoskeletal Diseases
Study type: Interventional

Summary: 
      Acceptance and Commitment Therapy (ACT) has been recognized as an effective,
      non-pharmacologic treatment for a variety of CP conditions. However, little is known about
      the neurologic mechanisms underlying ACT. The investigators conducted an ACT intervention in
      women (n=9) with chronic musculoskeletal pain. Functional magnetic resonance imaging (fMRI)
      data were collected pre- and post-ACT, and changes in functional connectivity (FC) were
      measured using Network-Based Statistics (NBS). Behavioral outcomes were measured using
      validated assessments such as the Acceptance & Action Questionnaire (AAQ-II), the Chronic
      Pain Acceptance Questionnaire (CPAQ), the Center for Epidemiologic Studies Depression Scale
      (CES-D), and the NIH Toolbox Neuro-QoLTM (Quality of Life in Neurological Disorders) scales.

      Results suggest that, following the four-week ACT intervention, participants exhibited
      reductions in brain activation within and between key networks including self-reflection
      (default mode, DMN), emotion (salience, SN), and cognitive control (frontal parietal, FPN).
      These changes in connectivity strength were correlated with changes in behavioral outcomes
      including decreased depression and pain interference, and increased participation in social
      roles. This study is one of the first to demonstrate that improved function across the DMN,
      SN, and FPN may drive the positive outcomes associated with ACT. This study contributes to
      the emerging evidence supporting the use of neurophysiological indices to characterize
      treatment effects of alternative and complementary mind-body therapies.
    

Detailed description: 
      Over 100 million Americans suffer from chronic pain (CP), which causes more disability than
      any other medical condition in the U.S. at a cost of $560-$635 billion per year. Opioid
      analgesics are frequently used to treat CP. However, long term use of opioids can cause brain
      changes such as opioid-induced hyperalgesia that, over time, increase pain sensation. Also,
      opioids fail to treat complex psychological factors that worsen pain-related disability,
      including beliefs and emotional responses to pain. Cognitive behavioral therapy (CBT) can be
      efficacious for CP. However, CBT does not focus on important factors needed for long-term
      functional improvement, including attainment of personal goals and the psychological
      flexibility to choose responses to pain.

      Acceptance and Commitment Therapy (ACT) is a mindfulness-based therapy that focuses on
      enabling individuals to accept what is out of their control, and to commit to valued actions
      that enrich their lives. ACT was developed in 1986 by Stephen C. Hayes who began to examine
      how language and thought influence internal experiences. By emphasizing acceptance instead of
      avoidance, ACT differs from many other forms of cognitive behavioral therapy. Although not
      originally designed for CP, ACT has been shown to be efficacious in terms of clinical
      outcomes, adherence to treatment, and retention, earning the status of a "well-established"
      treatment for CP from the American Psychological Association. ACT aims to increase
      psychological flexibility, and has been associated with improved health outcomes in many
      randomized controlled clinical trials, including three systematic reviews specific to CP.
      Psychological flexibility is defined as an individual's ability to "recognize and adapt to
      various situational demands; shift mindsets or behavioral repertoires when these strategies
      compromise personal or social functioning; maintain balance among important life domains; and
      be aware, open, and committed to behaviors that are congruent with deeply held values." ACT
      is a "third wave" behavioral treatment that has been shown to be efficacious for treating CP,
      as well as co-morbid conditions and factors (e.g., goal selection) related to long-term
      functional improvement. Additionally, patients who participate in ACT report greater
      long-term satisfaction compared to CBT. ACT is transdiagnostic and associated with
      improvements in physical functioning and pain-related disability, as well as decreases in
      emotional distress regardless of perceived pain intensity.

      Resting-state functional magnetic resonance imaging (rsfMRI) allows for data to be collected
      while individuals with CP rest in the MRI scanner for a short period of time (<10 minutes).
      Thus, data provides information about the natural state of brain function in CP without
      having to apply any external sensory or cognitive stimulation. Analysis methods of rsfMRI
      have focused on multiple regions in the brain, targeting inherent and altered measures of
      connectivity between brain regions and within brain networks. Further, alterations in brain
      structure and function have been demonstrated in multiple CP syndromes. Prior imaging
      research has suggested that CP results in abnormal hyper-connectivity of brain networks
      associated with self-reflection (default mode, DMN), emotion (salience, SN), and cognitive
      control (frontal parietal, FPN) networks. While ACT has been successful in helping those with
      CP create a more functional and personally meaningful life, a critical gap in the
      understanding of the neural mechanisms underlying ACT remains.

      Only two prior investigations have used fMRI to assess neural mechanisms of ACT-based
      interventions for CP. The first investigated task fMRI activation using pressure evoked pain.
      Participants with fibromyalgia showed increased activation in the ventrolateral prefrontal
      cortex (vlPFC) and orbitofrontal cortex (OFC) post-ACT after 12 weeks of ACT. Additionally,
      results showed pain-evoked changes in connectivity between the vlPFC and thalamus after ACT.
      Researchers in the second investigation conducted an 8-week ACT intervention vs. health
      education control (HEC) for participants with comorbid CP and opioid addiction. Focusing on
      DMN and pain regions in the brain, participants receiving ACT exhibited decreased activation
      during evoked pain in the middle frontal gyrus (MFG), inferior parietal lobule (IPL), insula,
      anterior cingulate cortex (aCC), posterior cingulate cortex (pCC), and superior temporal
      gyrus (STG) compared with HEC participants.

      In the present study, ACT was delivered to nine women with CP. fMRI was used to identify
      changes in brain networks underlying ACT-related behavioral outcomes in CP. Based on prior
      work examining ACT in CP, the investigators hypothesize that: (1) ACT will reduce
      connectivity strength within and between the DMN, SN, and FPN, and that (2) changes in
      connectivity strength will correlate with changes in behavioral outcomes from pre- to
      post-ACT.
    

Intervention name(s): Acceptance and Committment Therapy
Intervention type(s): Behavioral
Intervention description(s): Acceptance and Commitment Therapy (ACT) is a mindfulness-based therapy that focuses on enabling individuals to accept what is out of their control, and to commit to valued actions that enrich their lives (Vowles & McCracken, 2008). By emphasizing acceptance instead of avoidance, ACT differs from many other forms of cognitive behavioral therapy. ACT has been shown to be efficacious in terms of clinical outcomes, adherence to treatment, and retention. ACT aims to increase psychological flexibility, and has been associated with improved health outcomes prior randomized controlled clinical trials, including three systematic reviews specific to CP. Psychological flexibility is defined as an individual's ability to recognize and adapt to various demands; shift mindsets or behavioral responses when these strategies compromise personal or social functioning; and maintain balance among important life domains.
Intervention model: Single Group Assignment
Intervention model description: Pre-post (quasi-experimental) design assessing the neural mechanisms underlying and behavioral changes associated with a 4 week Acceptance and Committment Therapy (ACT) intervention among participants with chronic musculoskeletal pain.
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: Acceptance and commitment therapy; chronic pain; brain networks; functional connectivity; graph theory; fMRI