Abstract
Objective:
Although mindfulness meditation (MM) is increasingly used for chronic pain treatment, limited evidence supports its clinical application for opioid-treated chronic low back pain (CLBP). The goal of this study was to determine feasibility, acceptability, and safety of an MM-based intervention in patients with CLBP requiring daily opioid therapy.
Design:
26-week pilot randomized controlled trial comparing MM-based intervention, combined with usual care, to usual care alone.
Setting:
Outpatient.
Patients:
Adults with CLBP treated with ≥30 mg of morphine-equivalent dose (MED) per day for 3 months or longer.
Interventions:
Targeted MM-based intervention consisted of eight weekly 2-hour group sessions and home practice (30 minutes/d, 6 days/wk) during the study. “Usual care” for opioid-treated CLBP was provided to participants by their regular clinicians.
Outcome measures:
Feasibility and acceptability of the MM intervention were assessed by adherence to intervention protocol and treatment satisfaction among experimental participants. Safety was evaluated by inquiry about side effects/adverse events and opioid dose among all study participants.
Results:
Thirty-five participants enrolled during the 10-week recruitment period. The mean age (±standard deviation) was 51.8 ± 9.7 years; the patients were predominantly female, with substantial CLBP-related pain and disability, and treated with 148.3 ± 129.2 mg of MED per day. All participants completed baseline assessments; none missed both follow-up assessments or withdrew. Among experimental participants (n = 21), 19 attended 1 or more intervention sessions and 14 attended 4 or more. They reported, on average, 164.0 ± 122.1 minutes of formal practice per week during the 26-week study and 103.5 ± 111.5 minutes of brief, informal practice per week. Seventeen patients evaluated the intervention, indicating satisfaction; their qualitative responses described the course as useful for pain management (n = 10) and for improving pain coping skills (n = 8). No serious adverse events or safety concerns occurred among the study participants.
Conclusions:
MM-based intervention is feasible, acceptable, and safe in opioid-treated CLBP.
Introduction
C
Psychological therapies and complementary and integrative health approaches are ideal for CLBP management. Psychological therapies, especially cognitive-behavioral therapy (CBT), have shown some benefit for reducing pain and improving function, mental health, and quality of life; complementary and integrative health approaches have been reported by patients to provide benefit. 1 Patient preference and satisfaction regarding therapeutic modalities for CLBP are essential considerations because they can affect treatment adherence and choices. 6,7 Patients continue to show interest in new, less risky complementary and integrative health approaches, 7,8 rendering these modalities more likely to result in a sustained patient engagement, which may further treatment benefits. Feasibility, acceptability, and safety, crucial aspects of patient satisfaction and treatment effectiveness, 9 are important to address when considering different therapies.
Current research supports the use of mindfulness meditation (MM), a popular mind–body complementary and integrative health modality, for chronic pain. MM encourages the intentional engagement of acceptance and nonjudgmental attention to one's current state of body and mind, without becoming preoccupied by it. 10,11 Through its “observe and accept” approach, MM can cultivate an ability to disentangle a given experience (e.g., pain) from associated emotions, thoughts, or reactions (e.g., catastrophizing) to decrease the experience of suffering and promote a more skillful response to challenges. 12,13 MM practice can provide a foundation for engagement in life from a place of “being with” one's experiences that, when maintained over time, can have long-lasting effects. 14 –17 It can result in unique skills for chronic pain management, such as acceptance, complementing those acquired through CBT, a part of “usual care” for chronic pain, 18 –22 and potentially enhancing its benefits. 21 –26
MM is perceived as safe and effective for pain reduction and has established empirical support for reducing symptoms of anxiety, depression, and stress—all problems commonly co-occurring with and affecting outcomes in chronic pain. 27,28 Research has indicated that MM practice can influence function of the brain areas associated with pain, attention, and emotional response, implicating them as potential mechanisms of action. 29 However, evidence on MM's efficacy for chronic pain is limited and mixed, and MM and CBT interventions have not been sufficiently studied in patients with chronic pain requiring a long-term opioid therapy. 18,19,23,27,28,30 –35 A recent randomized controlled trial (RCT) (n = 115) found that a “mindfulness-oriented recovery enhancement” intervention, combining MM and CBT, led to decreases in pain severity and opioid desire ratings in adults with opioid-treated chronic pain; however, opioid dose was not quantified in this study. 23
Although MM and CBT have been shown as feasible and acceptable interventions for many chronic health conditions, 18,19,27 including depression, anxiety, and maladaptive stress or pain coping (problems commonly co-occurring with and affecting treatment outcomes in chronic pain 11,27,36 ), the Agency for Healthcare Research and Quality calls for systematic reporting on feasibility and safety of MM-based modalities. 27 It is important to evaluate the experience with, and effect of, these approaches among patients with opioid-treated chronic pain because their response to the MM intervention may differ from the response of those who do not require daily opioids. This population faces unique challenges related to both refractory pain and opioid therapy, including concerns about the ability to participate in and gain from a typical 8-week MM training, which requires multisession attendance and sustained attention on MM practice. Evaluation of an intervention, tailored to those with opioid-treated CLBP, is needed.
To address this gap, the authors developed an MM intervention for patients with opioid-treated CLBP, then tested its feasibility, acceptability, safety and efficacy in a 26-week pilot RCT. Efficacy results showed a decrease in pain severity ratings and sensitivity to experimental heat-pain stimuli at 26 weeks (p < 0.05) and are described elsewhere. 37 The current article presents the RCT's feasibility, acceptability, and safety findings, especially in relation to the MM intervention.
Materials and Methods
Trial design
The presented findings stem from the 26-week parallel-arm pilot RCT evaluating effects of the MM intervention, adjunctive to usual care (MM group), as compared with usual care alone (control group), among adults with opioid-treated CLBP. The control participants were offered the MM intervention after completing the study (wait-list). The procedures were approved by the institutional review board and registered with ClinicalTrials.gov before enrollment.
Participants
As detailed elsewhere, 37,38 potential participants were adults treated for CLBP with long-term daily opioids (≥3 months, ≥30 mg/d morphine-equivalent dose [MED]), identified through a search of the University of Wisconsin-Madison Department of Family Medicine and Community Health electronic medical record data, and referral from clinicians or self-referral via study brochures. Potential participants were screened by the study coordinator by phone and, if eligible and interested, met with her to proceed with enrollment, baseline assessment, and randomization. 37
Interventions
Usual care for opioid-treated CLBP 39 was provided to all participants by their regular clinicians, per their recommendations.
The experimental group additionally received the MM intervention, patterned after existing MM-based programs, 10,24 –26 and adapted to the psychophysical needs of the study population. The intervention was manualized and consisted of eight weekly 2-hour group sessions (Table 1) combining MM10,24–26 and pain-specific CBT 40 strategies. It was guided by two instructors (J.S. and S.M.), pain psychologists, each with more than 20 years of personal practice and more than 10 years of MM teaching experience. Each session included the review of home practice and questions; introduction to the session's core concepts; and session-specific exercises (concept application), followed by discussion of participant experiences and skills for coping with challenges related to opioid-treated CLBP. Session-specific exercises included extensive engagement in mindfulness techniques to facilitate learning of mindfulness-based pain coping.
For home practice, participants received three CDs containing seven guided meditations (body scan, mountain, two breath meditations, loving kindness, “silence with bells,” and SABER mini-meditation), recorded by the intervention instructors.
Pain wave surfing: this exercise promotes staying present with uncomfortable pain sensations, without becoming overwhelmed by or automatically reacting to them (adapted from the “urge surfing” exercise). 25,26
SABER: stop, acknowledge, breathe, expand, respond. This is a brief five-step mindfulness practice that can be used in physically, mentally, or emotionally distressing situations to facilitate pausing, decrease inner suffering, and create a healthier, mindful response to the situation (adapted from the existing brief SOBER meditation). 25,26
MM, mindfulness meditation.
Key MM techniques included (1) breath meditation practice of bringing awareness to the breath after the mind wanders away, providing practice of not becoming engaged in catastrophizing or rumination about pain; (2) body scan meditation practice of awareness of interoceptive, bodily sensations while engaged in acceptance and nonjudgment of present-moment experiences, including pain; (3) mindful walking, movement or stretching to further practice mindful awareness of interoceptive sensations, such as pain, during movement and facilitate better understanding of one's physical capacity, which, in turn, may promote a healthy engagement in physical activity; (4) loving kindness meditation to practice kindness to and acceptance of, rather than judgment of, one's pain experience; and (5) brief mindfulness techniques designed to be used throughout the day for an “informal” practice or for as-needed pain/stress coping. These “mini-meditations” included pain-wave surfing and SABER (stop, acknowledge, breathe, expand, respond) techniques (Table 1). Their goal was to enable practice of acceptance and nonjudgmental awareness of sensations, thoughts, and emotions within present-moment experiences to allow opportunity for a mindful, healthy response, rather than a habitual, maladaptive reaction (e.g., catastrophizing, rumination, acting out), to pain and other daily stressors.
Treatment fidelity was monitored 41 by using protocol-driven therapist selection and training and intervention delivery, audio-recording and auditing of the sessions to ensure therapist adherence to the manual, and assessment of participant treatment receipt and enactment during each session.
In addition to attending the intervention sessions, MM participants were asked to practice MM formally at home (≥6 days per week, ≥30 minutes per day; e.g., sitting meditation) and engage daily in brief, “informal” exercises (e.g., pain-wave surfing, mindful pause, or SABER) throughout the study. To enhance practice, they received three CDs containing guided meditations, recorded by the study instructors (Table 1).
Procedures/settings
On the basis of previous research and clinical experience, the plan was to enroll a convenience sample of 20–50 participants (10–25 participants per group) to ensure an optimal setting for group sessions of the MM intervention and enable gathering of pilot data. Therefore, 52 randomization envelopes were prepared with the goal of 1:1 randomization ratio. During the designated recruitment period (January–March 2013), 35 participants were enrolled, with 21 individuals randomly assigned to the MM group and 14 individuals to the control group.
Enrollment and assessment occurred at the University of Wisconsin-Madison's Clinical Research Unit (CRU). The intervention was delivered at one of the university's clinics (March–May 2013). Eligible participants met with the research coordinator to discuss study details and complete the written informed consent procedures, followed by baseline data collection and, finally, randomization (planned 1:1 ratio, with consecutively distributed sealed envelopes, prepared by the study statistician, using Minitab software, version 12).
After baseline data collection, experimental participants received information about the intervention, whereas controls were reminded about eligibility for crossover training after their study completion. Participants and study personnel were not blinded to group status.
Efficacy-related outcomes included self-reported, biomarker, and pain sensitivity measures, collected at baseline, 8 weeks (post-intervention) and 26 weeks, and are described in detail elsewhere; 37 pain severity (0–10 numeric rating scale from Brief Pain Inventory 42 ) and physical function (0%–100% Oswestry Disability Index scale 43 ) served as primary outcome measures, and daily MED of opioids served as secondary outcome measure. Data were collected by phone or mail from those unable to follow up in person. Participants were reimbursed for time and effort (maximum $180 for the assessment visits; a $10 gas card for each attended intervention session).
Outcome measures
Feasibility and acceptability
Feasibility and acceptability of the MM intervention were assessed among MM participants (n = 21) by their adherence to the intervention protocol and treatment satisfaction and experience evaluations.
Protocol adherence was measured by researcher-recorded participant intervention session attendance and participant-reported formal and informal home MM practice (number of days per week; number of minutes per day), enabling calculation of the number of practice minutes per week. During the intervention (weeks 1–8), participants logged their practice daily, with the logs collected weekly. During weeks 9–26, participants logged their practice weekly, with the logs collected at the 26-week follow-up. The logs were developed by the researchers.
Treatment satisfaction and experience were assessed at the final intervention session by using both quantitative (0–10 Likert scale responses; 10 = “very likely/very important”) and qualitative, open-ended questions from the researcher-developed Treatment Satisfaction Survey. 25
Safety
Safety was assessed among all participants (n = 35) by evaluating presence of side effects/adverse events at each contact (logged into a standardized CRU reporting form, then assessed by the study physician) and percentage of participants treated with high daily dose of opioids (MED >200 mg/d); treatment with high dose of opioids has been shown to increase the risk for opioid-related harm, including overdose death. 44 Average daily MED was calculated on the basis of participant self-reported daily use of opioid medications, verified against medication bottle information, for the “past 28 days,” using the timeline follow-back method, a reliable and validated tool for collecting daily substance use data, 45,46 and a researcher-developed Medication Use Survey.
Statistical analysis
IBM SPSS Statistics (version 21) software was used to analyze numeric data. Statistical significance was set at a two-tailed p-value <0.05. Because of the pilot nature of this study, no correction for multiplicity was applied. Success of randomization was evaluated by comparing the two groups on baseline characteristics, using the Mann–Whitney test for continuous data and chi-square test for nominal data. The paired Wilcoxon signed-rank test assessed within-group change in MM practice minutes during the study.
Qualitative analysis methods 47,48 were applied to qualitative data on treatment satisfaction and experience using open coding. Two experienced coders (A.Z., C.B.) independently reviewed all qualitative comments for each open-ended question. The grounded theory approach was used to identify repeated, emerging ideas and concepts. The coders then discussed the results and finalized the coding protocol. They then independently coded data into the major themes and response categories for each question. Data categorization and quantification were finalized through an iterative process and a consensus approach to disagreements.
Results
Baseline characteristics
From among 304 identified prospective participants, 87 were screened (39 ineligible; 13 eligible, declined), and 35 (21 MM, 14 control) were eligible and enrolled. 38 As reported elsewhere, most participants were white (80%) and female (80%), with 66% reporting $15,000 or less in individual annual income. 38 They were on average middle-aged (51.8 ± 9.7 years), with 14.2 ± 10.1-year history of back pain and 7.9 ± 5.7 years of opioid therapy. 38 They reported substantial averaged pain severity (5.8 ± 1.4), at least severe disability (66.7 ± 11.4), and moderate- to high-dose opioid therapy (148.3 ± 129.2 mg/d MED) in the “past 28 days.” At baseline, the MM group reported worse pain than controls (p = 0.001); otherwise the groups did not differ on sociodemographic characteristics, disability scores, or opioid dose (p > 0.05) (Table 2).
Values expressed with a plus/minus sign are the mean ± standard deviation.
GED, general educational development.
Retention and primary outcome data collection
The 10-week recruitment period yielded 35 enrolled participants. No participant withdrew (100% retention). Primary outcome data were provided by all participants at baseline, 34 participants at 8 weeks (missing 1 MM participant), and 33 participants at 26 weeks (missing 1 MM and 1 control participant), yielding an overall 91.4% adherence rate. No participants missed both follow-ups.
Feasibility and acceptability of the MM intervention
Adherence to MM intervention (n = 21)
Session attendance and engagement in MM practice measured adherence to the MM intervention. Two MM participants did not attend any sessions, citing lack of interest/time, 5 attended 3 or fewer sessions, and 14 attended 4 or more sessions. Those attending 3 or fewer sessions stopped attendance in the first half of the intervention, reporting health (n = 2), transportation (n = 1), or scheduling (n = 1) problems or lack of interest (n = 1). There were no statistically significant differences in baseline characteristics between those who attended 4 or more and those who attended 3 or fewer sessions.
During the study, 19 MM participants provided complete data on their home MM practice, and 2 provided partial data that were used to estimate their average minutes of practice per week during a given assessment period. During weeks 1–8 (intervention period), MM participants reported approximately 3 hours of formal and 2 hours of informal practice (Table 3), conducted on 5.1 ± 2.1 and 4.9 ± 2.0 days per week, respectively, with 11 participants exceeding 180 minutes of formal practice per week and 14 exceeding 150 minutes per week. During weeks 9–26, they maintained their practice minutes (Table 3), with 7 exceeding 180 minutes of formal practice per week and 10 exceeding 150 minutes per week; however, they decreased the number of formal and informal practice days per week compared with the intervention period (4.1 ± 2.6 days per week, p = 0.085; 4.2 ± 2.5 days per week, p = 0.028, respectively). Overall, during weeks 9–26, 18 patients continued MM practice, 2 stopped practicing, and 1 declined to provide data.
Paired Wilcoxon signed-rank test was used to compare the change in a given MM practice over time; weeks 1–8 represented the intervention period.
Values expressed with a plus/minus sign are the mean ± standard deviation.
The consistency of a higher-dose MM practice was evaluated on the basis of the pattern of formal practice during the study's three periods: weeks 1–8, 9–16, and 17–26. Those reporting on average at least 150 minutes of formal practice per week (representing over 80% of the study-recommended 180 minutes per week “dose”) during at least two thirds of the study periods were defined as “consistent” meditators (n = 10), while the remaining participants (n = 11) were classified as “inconsistent” meditators. “Consistent” meditators maintained a stable level of formal and informal practices, whereas “inconsistent” meditators showed a decline in both formal (p = 0.015) and informal (p = 0.008) practices over time (Table 3); these subgroups did not differ (p ≥ 0.05) for baseline characteristics, session attendance (5.3 ± 2.5 versus 4.2 ± 3.1, respectively), or treatment satisfaction ratings.
Treatment satisfaction and experience (n = 17)
Seventeen MM participants filled out the “satisfaction” survey, rating the intervention as “important” (8.0 ± 1.8) and “useful” for coping with back pain (7.2 ± 2.4) and stating they were likely to continue formal (8.1 ± 2.8) and informal (9.4 ± 1.0) practices. Responses to the open-ended treatment experience questions formed several themes (Table 4). When starting the intervention, participants hoped to improve pain control and coping skills, reduce reliance on analgesics, and learn to meditate. After the intervention, they indicated the MM training was useful for CLBP management and “general” coping and noted the importance of peer support. They identified pain flare and scheduling conflicts as main barriers to practice and suggested making the intervention longer and more available to others. Throughout their responses, participants emphasized the importance of brief, informal practices, describing them as “easy to fit them into my day,” “I can do this anywhere,” “It helps me in everyday living.”
Q, question.
Safety
During the study, none of the 35 participants reported serious or unexpected side effects or adverse events. Several MM participants noted self-limited, mild side effects during the intervention (increased pain with movement or while learning to “observe” pain experiences, n = 2; increased anxiety/emotional distress during practice, n = 3; increased cigarette smoking, n = 1; and weight gain, n = 1). The percentage of participants treated with more than 200 mg of MED per day decreased slightly in the experimental (from 28.6% to 20.0%) but not control (from 21.4% to 23.1%) group by 26 weeks (Table 5).
Values are expressed as percentage (number) of participants.
Data provided by 21, 20, and 20 experimental participants at baseline, 8 weeks, and 26 weeks, respectively.
Data provided by 14, 14, and 13 control participants at baseline, 8 weeks, and 26 weeks, respectively.
MED, morphine-equivalent dose.
Discussion
Findings of this study document feasibility, acceptability, and safety of the MM intervention and other study methods among opioid-treated patients with disabling CLBP.
These findings are important for clinical practice and research. Patients with opioid-treated chronic pain are in a desperate need of new, effective, and safe treatments. 4 Although research on the efficacy of MM-based interventions for reducing pain is promising, existing evidence on MM's effects for pain and/or function in chronic noncancer pain is inconclusive and based on a limited number of rigorous RCTs. 27,34,35,49 In addition, there is an overall scarcity of research on long-term efficacy of therapeutic modalities, including MM and CBT, in opioid-treated populations. 5,18,19,27,34,35,49 Although MM modalities are overall considered feasible, acceptable, and safe, these aspects of MM interventions have not been well explored in, and evidence on their efficacy is insufficient for, opioid-treated CLBP. 27,28
Examining the details of MM practice is crucial for discerning whether particular practice patterns have a differential health impact. 27 This study extends the existing knowledge by evaluating effects of an MM intervention and reporting on the details of home MM practice among individuals with opioid-treated CLBP. The findings 37 of reduced pain severity and decreased pain sensitivity to nociceptive thermal stimuli in the MM group, as compared to the wait-list control group, during the 26-week study, are promising and consistent with those of an RCT by Garland et al. 23
Adherence to and high satisfaction with the MM intervention among the current study's severely disabled, opioid-treated patients support its feasibility and are encouraging, especially because one of the common reported barriers to MM intervention attendance and practice was pain flare. Teaching participants early-on techniques for pain flare management and/or providing an opportunity for “remote participation” (e.g., telemedicine) may help overcome these challenges, facilitating adherence. The evidence for efficacy of tele-delivered MM and CBT is promising 50 but has yet to be demonstrated among patients with opioid-treated chronic pain. Adherence may be further enhanced by extending this intervention to less affected patients, possibly preventing the need for opioid initiation or dose increase.
Improving adherence to MM practice and enactment of the intervention-taught skills is important, especially because MM skills can be retained and applied over the long term, 17 and the efficacy findings (published elsewhere) 37 suggested a “dose-response” relationship between the consistency/amount of MM practice and the magnitude of outcome improvement. Interestingly, MM participants in this study self-selected early on to those engaged in a “higher-dose” consistent practice, and those practicing less. Perhaps the consistent meditators were more intrinsically motivated, whereas the inconsistent ones needed the external reinforcement and structure of the intervention for continued practice. Development of strategies for identifying those at risk for nonadherence and boosting their engagement during and after the intervention may extend the potential benefits of MM practice to a larger group of patients.
The perceived safety of MM-based interventions 18,19,27,49 was corroborated by this research. It is in stark contrast to opioid therapy, which has been linked to dose-dependent harms. 5 Safe interventions that may enable patients to rely less on opioids could benefit health of individuals with chronic pain and, potentially, the broader society, as the impact of prescription opioid abuse has risen to the level of a public health crisis. 51 This experience and participant comments indicate the importance of adapting the intervention to the needs of this population. Although functional limitations were anticipated, after the first session it became clear that the severe physical disability of this population required further adaptations of the intervention manual, especially its “mindful movement” sections. Had the intervention not been cautiously tailored, the adherence could have been compromised.
Limitations, generalizability
Small sample size and medium-length follow-up duration may limit the generalizability of conclusions. In addition, patients who self-selected to the study may differ from their counterparts, potentially limiting result generalizability to a broader population of opioid-treated patients. Lack of blinding could have introduced bias, and lack of an active comparison group limits the ability to draw firm conclusions about the efficacy of the MM intervention because it does not allow disentangling of the effects related to the group experience (e.g., peer support; therapist contact) from those stemming from the intervention itself. Reliance on self-report as a means for tracking MM practice may not accurately reflect participant engagement in home practice. In addition, the responsibility of tracking and logging practice minutes may facilitate adherence to practice in a subgroup of participants. This can be an important consideration for MM programs, as strategies aimed at increasing adherence may potentiate therapeutic effects of MM intervention. Although the high rates of retention and adherence to primary outcome data collection in both groups suggest feasibility of the overall study methods, these measures are nonspecific, with their results potentially influenced by a variety of factors, including the monetary compensation offered to participants for the completion of study assessments. Evaluating the impact of specific elements of the study methods/intervention by future research could help identify components of feasibility and adherence that, if put into practice, may help enhance participant engagement.
Future directions
Patient interest in and satisfaction with MM, and promising evidence on salutary effects of MM and CBT, make MM-based interventions (especially those combining MM and CBT techniques) an excellent object of translational research. Future studies, evaluating effects of MM-based interventions for opioid-treated chronic pain, should consider using an active comparison group and assessing patient characteristics (“phenotype profiling”) and other factors that may predict patient engagement in a continued MM practice and favorable treatment response. The potential of MM intervention to help reduce patient reliance on opioids and opioid use could be of tremendous benefit to individual patients and society.
Conclusions
Findings of this study indicate that the targeted MM-based intervention is feasible and safe in patients with opioid-treated CLBP. MM-based interventions are particularly attractive for the treatment of chronic disabling conditions because they promote an acceptance-based, self-reflective process, which can encourage a patient-empowering and a personalized approach addressing the whole patient. This approach extends beyond the traditional, disease-focused treatment model of chronic pain and passive nature of pharmacotherapy, offering a valuable therapeutic option for those with refractory CLBP requiring daily opioid therapy.
Footnotes
Acknowledgments
The study is registered on ClinicalTrials.gov (NCT01775995). Dr. Zgierska's work was supported by the K23AA017508 award from the National Institutes of Health (NIH) National Institute on Alcohol Abuse and Alcoholism and by funds from the University of Wisconsin-Madison. The project was also supported by the Clinical and Translational Science Award program through the NIH National Center for Advancing Translational Sciences, grant UL1TR000427. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
Author Disclosure Statement
No competing financial interests exist.
