Measuring and reporting adverse events in clinical trials of psychological treatments for chronic pain

Current state of psychological therapies for children and adults with chronic pain: Where next?

Pain is influenced by biological, psychological and social factors. Whilst analgesics are often prescribed for chronic pain, they provide little benefit for most patients. Psychological therapies manage pain and disability in children and adults with chronic pain. Evidence for cognitive behavioural therapies is the most robust in the field, although benefits are modest. Technological innovation has led to Internet-delivered therapies, but innovation in research often lags behind technological developments due to funding and regulation. Despite the promising outlook, critical gaps in our knowledge of how to manage pain need addressing for both adults and children and their parents. Here we summarise the evidence base of psychological therapies using Cochrane reviews, gaps, and the role of preventing chronic pain onset.

Unwanted or negative treatment reactions in digital psychological interventions for adolescents with chronic pain

OBJECTIVE

Reports of pain clinical trials evaluating psychological treatments often lack sufficient details on the potential and actual harm resulting from intervention. We aimed to understand how frequent and intense treatment reactions, conceptualized as unwanted symptoms, were in three clinical trials of digital Cognitive Behavioral Therapy (CBT) for adolescents with: (1) chronic primary pain, (2) sickle cell disease, and (3) chronic pancreatitis. We also aimed to understand any differences by demographic and clinical variables.

METHOD

Analyses were conducted with 246 youths (12-18 years old) experiencing chronic pain and one of their caregivers. 66% of the total sample was female. The number, intensity, and type of treatment reactions experienced were assessed post treatment. T-tests and Chi-squared tests were conducted to explore whether certain treatment reactions were more frequent as a function of baseline or clinical characteristics.

RESULTS

9% of participants experienced some negative treatment reaction. The average intensity of those events was very low on a 0-3 scale (M = 0.1, SD = 0.4). There were no differences in the prevalence or intensity as a function of participant's sex, age, race, or baseline pain intensity. However, baseline anxiety [t = -2.4 (244); p < .05] and baseline pain interference [t = -2.2 (223); p < .05] were significantly higher in those who experienced negative treatment reactions.

CONCLUSIONS

A small number of participants reported experiencing negative treatment reactions, with a low intensity level. Those experiencing negative treatment reactions showed higher baseline anxiety and pain interference. Future research may build from our example to standardize collection of harms data in trials of psychological interventions.

Effect of Brain-Gut Behavioral Treatments on Abdominal Pain in Irritable Bowel Syndrome: Systematic Review and Network Meta-Analysis

BACKGROUND & AIMS

Some brain-gut behavioral treatments (BGBTs) are beneficial for global symptoms in irritable bowel syndrome (IBS). United States management guidelines suggest their use in patients with persistent abdominal pain, but their specific effect on this symptom has not been assessed systematically.

METHODS

We searched the literature through December 16, 2023, for randomized controlled trials (RCTs) assessing efficacy of BGBTs for adults with IBS, compared with each other or a control intervention. Trials provided an assessment of abdominal pain resolution or improvement at treatment completion. We extracted data as intention-to-treat analyses, assuming dropouts to be treatment failures and reporting pooled relative risks (RRs) of abdominal pain not improving with 95% confidence intervals (CIs), ranking therapies according to the P score.

RESULTS

We identified 42 eligible randomized controlled trials comprising 5220 participants. After treatment completion, the BGBTs with the largest numbers of trials and patients recruited demonstrating efficacy for abdominal pain, specifically, included self-guided/minimal contact cognitive behavioral therapy (CBT) (RR, 0.71; 95% CI, 0.54-0.95; P score, 0.58), face-to-face multicomponent behavioral therapy (RR, 0.72; 95% CI, 0.54-0.97; P score, 0.56), and face-to-face gut-directed hypnotherapy (RR, 0.77; 95% CI, 0.61-0.96; P score, 0.49). Among trials recruiting only patients with refractory global IBS symptoms, group CBT was more efficacious than routine care for abdominal pain, but no other significant differences were detected. No trials were low risk of bias across all domains, and there was evidence of funnel plot asymmetry.

CONCLUSIONS

Several BGBTs, including self-guided/minimal contact CBT, face-to-face multicomponent behavioral therapy, and face-to-face gut-directed hypnotherapy may be efficacious for abdominal pain in IBS, although none was superior to another.

Patient perspectives on the unwanted effects of multidisciplinary pain management programmes: A qualitative study

OBJECTIVE

This study aimed to understand the impact of pain management programmes, focusing on the unwanted effects and their influence on patients' long-term use of self-management strategies.

DESIGN

Qualitative study.

SETTING

Specialist musculoskeletal hospital in North London, England.

PARTICIPANTS

Patients with chronic musculoskeletal pain that have completed a pain management programme.

INTERVENTION

Multidisciplinary pain management programmes.

MAIN MEASURES

Data were collected regarding patients' experiences and unwanted effects from the pain management programme using semi-structured interviews. Data were analysed using thematic analysis.

RESULTS

Fourteen participant interviews were included in the analysis (median age 54 years, 12 females). Four themes were generated from the data: Benefits and burdens, Pain management programme and real life, Social support and Healthcare interventions. Unwanted effects included heightened anxiety related to negative interactions with peers, being in a new environment, worries about ability to cope with the programme, social anxiety from being in a group, the strain on families due to participants being away from home and a sense of abandonment at end of the programme. Burdens associated with implementing pain management strategies were identified, including the emotional burden of imposing their self-management on close family and competing demands with time and energy spent on self-management at the expense of work or home commitments.

CONCLUSIONS

Pain management programmes have an important role in helping patients to learn how to self-manage chronic pain. Their unwanted effects and the treatment burdens associated with long-term self-management may be an important consideration in improving the longevity of their beneficial effects.

Updated recommendations on measures for clinical trials in pediatric chronic pain: a multiphase approach from the Core Outcomes in Pediatric Persistent Pain (Core-OPPP) Workgroup

ABSTRACT

Many gaps remain in finding effective, safe, and equitable treatments for children and adolescents with chronic pain and in accessing treatments in different settings. A major goal of the field is to improve assessment of pain and related experience. Valid and reliable patient-reported outcome measures are critical for advancing knowledge of clinical interventions for pediatric chronic pain. Building on the work of the Ped-IMMPACT group, we previously updated a core outcome set (COS) for pediatric chronic pain clinical trials using stakeholder feedback from providers, youth, and parents. The new COS includes 3 mandatory domains: pain severity, pain-related interference with daily living, and adverse events and 4 optional domains: overall well-being, emotional functioning, physical functioning, and sleep quality. The aim of this study was to use a multiphased approach to recommend specific measures for each of the 7 domains identified in our new COS for pediatric chronic pain. We synthesized evidence through conducting the following: (1) a Delphi study of experts to identify candidate measures for the new COS domains, (2) a review phase to gather evidence for measurement properties for candidate measures, and (3) an expert consensus conference to reach agreement on measurement recommendations. Final recommendations included 9 patient-reported measures. Important contextual considerations are discussed, and guidance is provided regarding strengths and limitations of the recommendations. Implementation of these recommendations may be enhanced by widespread dissemination and ease of access to measurement tools.

Recording harms in randomized controlled trials of behavior change interventions: a scoping review and map of the evidence

OBJECTIVES

Randomized controlled trials evaluate diverse interventions. This can include medical interventions such as drugs or surgical procedures, or behavior change interventions (BCIs) that aim to change a habit, belief, or attitude to improve health, for example, healthy eating, psychological wellbeing. Harms are often recorded poorly or inconsistently within randomized controlled trials of BCIs. This scoping review aimed to collate and describe literature on categories, definitions, and mechanisms of harms from BCIs; methods of identifying plausible harms; and recommendations for recording harms.

STUDY DESIGN AND SETTING

A scoping review was conducted. Three databases (MEDLINE, PsycINFO, and CINAHL) were searched. Reference list checking and citation searching were performed. Articles were included if they discussed (1) interventions that aimed to modify behavior, (2) categories or mechanisms of harms, and (3) methods or recommendations for recording harms. All research designs were included. One reviewer reviewed titles, abstracts, and full texts; queries were checked with another reviewer. Data were extracted and synthesized descriptively by one reviewer and checked by another reviewer. A thematic map was constructed to summarize the review findings. Harms described from specific BCIs were identified, and examples were selected and summarized.

RESULTS

The review included 37 articles. Nineteen of 37 articles contributed to a thematic review. Three articles described categories of harms; categories of harm included physical, psychological, group and social interactions, cultural, equity, opportunity cost, environmental, and economic. Seven articles included mechanisms or underlying factors for harms including feelings of failure leading to shame or stigma, and group interventions enabling knowledge exchange on unhealthy behaviors. Twelve articles provided recommendations for recording harms, including taking a proportionate approach by focusing on the most plausible and important harms, collecting different perspectives on whether harms had occurred (eg, caregivers and family members), and using qualitative research methods to identify harms. One article described a three-step method to identify plausible harms from an intervention, and six articles supported aspects of the method. Eighteen of 37 articles contributed to a review which collated harms arising from specific interventions, for example, a peer support intervention in inflammatory bowel disease caused distressing conversations which might lead to anxiety and confrontation with a possible negative future.

CONCLUSION

BCIs can cause harm. This review identified categories and proposed mechanisms of harms, as well as methods and recommendations for identifying and recording harms in BCIs for inclusion in forthcoming recommendations.

Evaluation of a therapist-guided virtual psychological pain management program when provided as routine care: a prospective pragmatic cohort study

INTRODUCTION

Numerous randomized controlled trials have evaluated the outcomes of internet-delivered psychological pain management programs (PMPs) as a way of increasing access to care for people with chronic pain. However, there are few reports of the effectiveness of these PMPs when provided as part of routine care.

METHODS

The present study sought to report the clinical and demographic characteristics of users (n = 1367) and examine the effectiveness of an established internet-delivered psychological PMP program in improving several pain-related outcomes, when offered at a national digital mental health service over a 5-year period. It also sought to comprehensively explore predictors of treatment commencement, treatment completion, and clinical improvement.

RESULTS

Evidence of clinical improvements (% improvement; Hedges g) were found for all outcomes, including pain interference (18.9%; 0.55), depression (26.1%; 0.50), anxiety (23.9%; 0.39), pain intensity (12.8%; 0.41), pain self-efficacy (-23.8%; -0.46) and pain-catastrophizing (26.3%; 0.56). A small proportion of users enrolled but did not commence treatment (13%), however high levels of treatment completion (whole treatment = 63%; majority of the treatment = 75%) and satisfaction (very satisfied = 45%; satisfied = 37%) were observed among those who commenced treatment. There were a number of demographic and clinical factors associated with commencement, completion and improvement, but no decisive or dominant predictors were observed.

DISCUSSION

These findings highlight the effectiveness and acceptability of internet-delivered psychological PMPs in routine care and point to the need to consider how best to integrate these interventions into the pathways of care for people with chronic pain.

Effectiveness of non-pharmacological interventions for fibromyalgia and quality of review methods: an overview of Cochrane Reviews

BACKGROUND

Fibromyalgia syndrome (FMS) is defined as chronic widespread pain associated with sleep disorders, cognitive dysfunction, and somatic symptoms present for at least three months and cannot be better explained by another diagnosis.

OBJECTIVES

To examine efficacy and safety of non-pharmacological interventions for FMS in adults reported in Cochrane Reviews, and reporting quality of reviews.

METHODS

Systematic reviews of randomised controlled trials (RCTs) of non-pharmacological interventions for FMS were identified from the Cochrane Database of Systematic Reviews (CDSR 2022, Issue 3 and CDSR 2023 Issue 6). Methodological quality was assessed using the AMSTAR-2 tool and a set of methodological criteria critical for analgesic effects. The primary efficacy outcomes of interest were clinically relevant pain relief, improvement in health-related quality of life (HRQoL), acceptability, safety, and reduction of mobility difficulties as reported by study participants. No pooled analyses were planned. We assumed a clinically relevant improvement was a minimal clinically important difference (MCID) between interventions and controls of 15%, or a SMD of more than 0.2, or a MD of more than 0.5, on a 0 to 10 scale.

RESULTS

Ten Cochrane reviews were eligible, reporting 181 randomized or quasi- randomized trials (11,917 participants, average trial size 66 participants). The reviews examined exercise training, acupuncture, transcutaneous electrical nerve stimulation, and psychological therapies. One review was rated moderate according to AMSTAR 2, seven were rated low and two were rated critically low. All reviews met most of the additional methodological quality criteria. All reviews included studies with patient-reported outcomes for pain. We found low certainty evidence of clinically relevant positive effects of aerobic and mixed exercise training and for cognitive behavioural therapies (CBTs) at reducing mobility difficulties and for mixed exercise training and CBTs for improving HRQoL at the end of the intervention. Number needed to treat for an additional beneficial outcome (NNTB) values for a MCID of 15% ranged between 4 and 9. We found low certainty evidence that was clinically relevant for mixed exercise and CBTs for reducing mobility difficulties at an average follow up of 24 weeks. We found low certainty evidence of clinically relevant positive effects of mixed exercise on HRQoL at an average follow up of 24 weeks. NNTB values for a MCID of 15% ranged from 5 to 11. The certainty of evidence of the acceptability (measured by dropouts) of the different non-pharmacological interventions ranged from very low to moderate and the dropout rate for any reason did not differ across the interventions or the controls, except for biofeedback and movement therapies. All the systematic reviews stated that the reporting of adverse events was inconsistent in the studies analysed (very low certainty evidence).

AUTHORS' CONCLUSIONS

There is low certainty evidence of clinically relevant reduction of mobility difficulties and of improvement of HRQoL among individuals with FMS by aerobic and mixed exercise training and by CBTs at the end of the intervention. There is low certainty evidence that CBTs and mixed exercise training reduces mobility difficulties post-treatment and that mixed exercise training improves HRQoL at follow-up by clinically meaningful scores.

"Making Data the Drug": A Pragmatic Pilot Feasibility Randomized Crossover Trial of Data Visualization as an Intervention for Pediatric Chronic Pain

Data tracking is a common feature of pain e-health applications, however, viewing visualizations of this data has not been investigated for its potential as an intervention itself. We conducted a pilot feasibility parallel randomized cross-over trial, 1:1 allocation ratio. Participants were youth age 12-18 years recruited from a tertiary-level pediatric chronic pain clinic in Western Canada. Participants completed two weeks of Ecological Momentary Assessment (EMA) data collection, one of which also included access to a data visualization platform to view their results. Order of weeks was randomized, participants were not masked to group assignment. Objectives were to establish feasibility related to recruitment, retention, and participant experience. Of 146 youth approached, 48 were eligible and consented to participation, two actively withdrew prior to the EMA. Most participants reported satisfaction with the process and provided feedback on additional variables of interest. Technical issues with the data collection platform impacted participant experience and data analysis, and only 48% viewed the visualizations. Four youth reported adverse events not related to visualizations. Data visualization offers a promising clinical tool, and patient experience feedback is critical to modifying the platform and addressing technical issues to prepare for deployment in a larger trial.

Current Practices, Experiences, and Views in Clinical Hypnosis: Findings of an International Survey

An online survey of 691 clinicians who use hypnosis was conducted in 31 countries to gain a broad real-world picture of current practices, views, and experiences in clinical hypnosis. Among 36 common clinical uses, stress reduction, wellbeing and self-esteem-enhancement, surgery preparations, anxiety interventions, mindfulness facilitation, and labor and childbirth applications were the most frequently rated as highly effective (each by ≥70% of raters) in the clinicians' own experience. Adverse hypnosis-associated effects had been encountered by 55% of clinicians but were generally short-lived and very rarely judged as serious. The most common hypnosis approaches used were Ericksonian (71%), hypnotic relaxation therapy (55%), and traditional hypnosis (50%). Almost all respondents reported regularly using other therapeutic modalities alongside hypnosis. Among a range of client variables potentially affecting therapy, most clinicians rated hypnotist-client rapport (88%) and client motivation (75%) as very or extremely important factors for successful hypnotherapy. The majority of respondents had conducted hypnosis treatment via teletherapy, and 54% of those estimated it to be as effective as in-person treatment.

[Psychological aspects of pain prevention : German version]

How to prevent the onset, maintenance, or exacerbation of pain is a major focus of clinical pain science. Pain prevention can be distinctly organised into primary, secondary, and tertiary prevention. Primary prevention describes avoiding hurt or pain, secondary prevention describes reducing pain when pain is unavoidable, and tertiary prevention describes preventing or reducing ongoing negative consequences such as high functional disability or distress due to chronic pain. Each poses separate challenges where unique psychological factors will play a role. In this short review article, we highlight psychological factors important to primary, secondary, and tertiary prevention and provide direction for the field. We present 2 case studies on secondary prevention in children and adolescents and tertiary prevention in adults with chronic pain. Finally, we provide research directions for progression in this field, highlighting the importance of clear theoretical direction, the identification of risk factors for those most likely to develop pain, and the importance of treatment.

Evidence-based digital support during 1 year after an Interdisciplinary Pain Rehabilitation Programme for persons with chronic musculoskeletal pain to facilitate a sustainable return to work: a study protocol for a registry-based multicentre randomised controlled trial

INTRODUCTION

Chronic musculoskeletal pain (CMSP) severely affects the individual's quality of life, functioning and ability to work, and comes with significant societal costs for sick leave and productivity loss. After rehabilitation, patients with CMSP often experience lack of support when responsibility for the return-to-work process is taken over by the employer. Therefore, we aim to evaluate the effectiveness of a digital support (Sustainable WorkEr digital support for Persons with chronic Pain and their Employers (SWEPPE)) for promoting a sustainable return-to-work for persons with CMSP and to facilitate the employers' supportive role and responsibilities in the process.

METHODS AND ANALYSIS

In this registry-based multicentre randomised controlled trial, 360 patients with CMSP will be randomised to either receive the smartphone application SWEPPE (n=180) or to a control group (n=180). The intervention group will use SWEPPE for 1 year and the control group will not receive any intervention for return to work (RTW). Participants will be recruited from approximately 10 specialist and primary care level units connected to the Swedish National Quality Registry for Pain Rehabilitation providing Interdisciplinary Pain Rehabilitation Programmes (IPRP) for CMSP. Eligibility criteria are age 18-65 years and a need for support in RTW or continued support at work for creating a sustainable work situation. Baseline data will be collected when the participants have completed the IPRP. Final assessment will be performed after 12 months. The primary outcome will be a number of days with sickness cash benefit. Secondary outcomes and explanatory variables including important domains affected by CMSP such as health-related quality of life, functioning and work ability will be collected.

ETHICS AND DISSEMINATION

The Swedish Ethics Review Board approved the study (Dnr 2020-01593, Dnr 2021-01854). The study findings will be disseminated through publication, national and international conferences, and meetings to be available for patients, healthcare providers or stakeholders.

TRIAL REGISTRATION NUMBER

NCT05058547.

Effectiveness of the eVISualisation of physical activity and pain intervention (eVIS) in Swedish Interdisciplinary Pain Rehabilitation Programmes: study protocol for a registry-based randomised controlled clinical trial

INTRODUCTION

Living with chronic pain often involves negative consequences. Interdisciplinary Pain Rehabilitation Programmes (IPRP) is considered superior to single-treatment measures in patients with chronic pain. Despite this, effects emerge suboptimal and more than 20% of patients deteriorate in patient-reported physical health outcomes after IPRP. A novel e-Health intervention, eVISualisation (eVIS) of physical activity and pain, was systematically developed to facilitate individualisation of physical activity levels. By adding elements of data collection, visualisation and communication of objectively measured physical activity and patient-reported outcomes (pain intensity, interference of pain, pharmaceutical consumption) to existing treatment modalities in IPRP, the IPRP team acquires prerequisites to adapt advice and physical activity prescriptions and to evaluate set activity goals. The overall aim is twofold. First, the aim is to evaluate the feasibility of the subsequent registry-based randomised controlled clinical trial (R-RCT). Second, the aim is to prospectively evaluate the effectiveness of the eVIS-intervention as a supplement to IPRP on our defined primary (physical health) and secondary outcomes.

METHODS AND ANALYSIS

In the R-RCT, recruitment of 400 patients with chronic pain will be performed at 15 IPRP units. A random allocation to either IPRP + eVIS or to control group that will receive IPRP only will be performed. Data from the initial 30 participants completing the study period (6 months) will be included in a pilot study, where key feasibility outcomes (recruitment, randomisation, implementation, treatment integrity, data collection procedure, preliminary outcome measures) will be evaluated. Outcome variables will be extracted from the web application Pain And TRaining ON-line (PATRON) and from six national registries. Multivariate statistics and repeated measure analyses will be performed. Quality-adjusted life years and incremental cost-effectiveness ratio will be calculated for cost-effectiveness evaluation.

ETHICS/DISSEMINATION

The Swedish Ethics Review Board granted approval (Dnr 2021/02109). Results will be disseminated through peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05009459. Protocol V.1.

The Pain Course: a randomised controlled trial and economic evaluation of an internet-delivered pain management program

ABSTRACT

There is interest in the potential of Internet-delivered programs to cost-effectively increase access to pain management for people with chronic pain. However, few large-scale clinical and economic evaluations have been undertaken. Using a randomised controlled trial design, the current study (n = 659) examined the clinical efficacy, cost-effectiveness, and cost utility of an Internet-delivered pain management program for people with mixed chronic pain conditions when delivered with optional clinician support. The treatment group reported significant improvements in disability, depression, anxiety, average pain intensity, and quality-adjusted life years (QALYs), compared with control, and exhibited relatively high levels of treatment engagement and satisfaction. Each additional clinical improvement (defined as ≥ 30% improvement) produced by the intervention, over control, was associated with a cost of $48, $27, $38, and $83 for disability, depression, anxiety, and average pain intensity, respectively. Gaining one QALY was associated with a cost of $152 or $11,910 per QALY when an 80% probability criterion for cost utility was applied. The program itself was associated a relatively small, fixed, cost per patient but was not cost saving over the brief intervention period. The findings support the clinical efficacy and cost-effectiveness of Internet-delivered programs with "on demand" clinician support as a way to increase access to pain management. Key limitations of the current study include the use of a waitlist-control group, a short follow-up period, and the focus on governmental healthcare costs. Further evaluation of these programs is necessary if they are scaled up and offered as routine care.

Cognitive therapy, mindfulness-based stress reduction, and behavior therapy for the treatment of chronic pain: randomized controlled trial

ABSTRACT

Trials of cognitive therapy (CT), mindfulness-based stress reduction (MBSR), and behavior therapy (BT) suggest that all 3 treatments produce reductions in pain and improvements in physical function, mood, and sleep disturbance in people with chronic pain conditions. Fewer studies have compared the relative efficacies of these treatments. In this randomized controlled study, we compared CT, MBSR, BT, and treatment as usual (TAU) in a sample of people with chronic low back pain (N = 521). Eight individual sessions were administered with weekly assessments of outcomes. Consistent with the prior work, we found that CT, MBSR, and BT produced similar pretreatment to posttreatment effects on all outcomes and revealed similar levels of maintenance of treatment gains at 6-month follow-up. All 3 active treatments produced greater improvements than TAU. Weekly assessments allowed us to assess rates of change; ie, how quickly a given treatment produced significant differences, compared with TAU, on a given outcome. The 3 treatments differed significantly from TAU on average by session 6, and this rate of treatment effect was consistent across all treatments. Results suggest the possibility that the specific techniques included in CT, MBSR, and BT may be less important for producing benefits than people participating in any techniques rooted in these evidence-based psychosocial treatments for chronic pain.

Psychological aspects of pain prevention

How to prevent the onset, maintenance, or exacerbation of pain is a major focus of clinical pain science. Pain prevention can be distinctly organised into primary, secondary, and tertiary prevention. Primary prevention describes avoiding hurt or pain, secondary prevention describes reducing pain when pain is unavoidable, and tertiary prevention describes preventing or reducing ongoing negative consequences such as high functional disability or distress due to chronic pain. Each poses separate challenges where unique psychological factors will play a role. In this short review article, we highlight psychological factors important to primary, secondary, and tertiary prevention and provide direction for the field. We present 2 case studies on secondary prevention in children and adolescents and tertiary prevention in adults with chronic pain. Finally, we provide research directions for progression in this field, highlighting the importance of clear theoretical direction, the identification of risk factors for those most likely to develop pain, and the importance of treatment.

Effect of Transversus abdominis muscle training on pressure-pain threshold in patients with chronic low Back pain

Background

Therapeutic training is the most commonly used treatment methods for chronic low back pain (CLBP), and the use of a pressure biofeedback unit for transversus abdominis muscle (TrA) training is one of the core muscle training methods. The study aim of this research is to explore the effects of different intensities (sham training, low-intensity and high-intensity) of TrA muscle training on people with CLBP in pressure-pain threshold (PPT).

Methods

A total of 45 patients with CLBP were recruited, of whom 44 were included in the analysis. Fifteen, 14, and 15 were included in the sham training group, the low-intensity group, and the high-intensity group, respectively. A pressure biofeedback unit was used in performing a one-time TrA training intervention involving 30 times of 180 mmHg TrA contraction training at high intensity for 10 min and 15 times of 100 mmHg TrA contraction training at low intensity for 5 min. The sham training group completed comfort exercises and did not undergo training. The evaluation indicators were as follows: PPT, short-form McGill pain questionnaire, and body surface pain radiation.

Results

High-intensity training could activate more waist core muscles than low-intensity training. Significant changes on PPT (units: kgf) were observed in the following four muscles immediately after high-intensity training: iliopsoas [0.69 (0.13–1.25) 95% CI, p = 0.020]; quadratus lumborum [0.84 (0.23–1.45) 95% CI, p = 0.012]; erector spinae [0.66 (0.18–1.15) 95% CI, p = 0.011]; transversus abdominis [0.70 (0.26–1.14) 95% CI, p = 0.004], and in three muscles after low-intensity training: quadratus lumborum [0.61 (0.17–1.05) 95% CI, p = 0.009]; transversus abdominis [0.14 (from − 0.15 to 0.43) 95% CI, p = 0.022]; piriformis [0.55 (0.13–0.98) 95% CI, p = 0.014]. The change in body surface pain radiation immediately after exercise was [− 10.87 (from − 17.51 to − 4.22) 95% CI, p = 0.003] for high-intensity training and [− 5.21 (from − 9.40 to − 1.03) 95% CI, p = 0.019] for low-intensity training.

Conclusions

TrA training could increase the PPT of the waist core muscles and reduce the radiation range of waist pain. The benefits of high-intensity training are higher than those of low-intensity training.

Trial registration

ChiCTR-TRC-13003701. Registered 18 October 2013.

Code of ethical approval: 2018069.

Psychological therapies for the management of chronic pain (excluding headache) in adults

BACKGROUND

Chronic non-cancer pain, a disabling and distressing condition, is common in adults. It is a global public health problem and economic burden on health and social care systems and on people with chronic pain. Psychological treatments aim to reduce pain, disability and distress. This review updates and extends its previous version, published in 2012.

OBJECTIVES

To determine the clinical efficacy and safety of psychological interventions for chronic pain in adults (age > 18 years) compared with active controls, or waiting list/treatment as usual (TAU).

SEARCH METHODS

We identified randomised controlled trials (RCTs) of psychological therapies by searching CENTRAL, MEDLINE, Embase and PsycINFO to 16 April 2020. We also examined reference lists and trial registries, and searched for studies citing retrieved trials.

SELECTION CRITERIA

RCTs of psychological treatments compared with active control or TAU of face-to-face therapies for adults with chronic pain. We excluded studies of headache or malignant disease, and those with fewer than 20 participants in any arm at treatment end.

DATA COLLECTION AND ANALYSIS

Two or more authors rated risk of bias, extracted data, and judged quality of evidence (GRADE). We compared cognitive behavioural therapy (CBT), behavioural therapy (BT), and acceptance and commitment therapy (ACT) with active control or TAU at treatment end, and at six month to 12 month follow-up. We did not analyse the few trials of other psychological treatments. We assessed treatment effectiveness for pain intensity, disability, and distress. We extracted data on adverse events (AEs) associated with treatment.

MAIN RESULTS

We added 41 studies (6255 participants) to 34 of the previous review's 42 studies, and now have 75 studies in total (9401 participants at treatment end). Most participants had fibromyalgia, chronic low back pain, rheumatoid arthritis, or mixed chronic pain. Most risk of bias domains were at high or unclear risk of bias, with selective reporting and treatment expectations mostly at unclear risk of bias. AEs were inadequately recorded and/or reported across studies. CBT The largest evidence base was for CBT (59 studies). CBT versus active control showed very small benefit at treatment end for pain (standardised mean difference (SMD) -0.09, 95% confidence interval (CI) -0.17 to -0.01; 3235 participants; 23 studies; moderate-quality evidence), disability (SMD -0.12, 95% CI -0.20 to -0.04; 2543 participants; 19 studies; moderate-quality evidence), and distress (SMD -0.09, 95% CI -0.18 to -0.00; 3297 participants; 24 studies; moderate-quality evidence). We found small benefits for CBT over TAU at treatment end for pain (SMD -0.22, 95% CI -0.33 to -0.10; 2572 participants; 29 studies; moderate-quality evidence), disability (SMD -0.32, 95% CI -0.45 to -0.19; 2524 participants; 28 studies; low-quality evidence), and distress (SMD -0.34, 95% CI -0.44 to -0.24; 2559 participants; 27 studies; moderate-quality evidence). Effects were largely maintained at follow-up for CBT versus TAU, but not for CBT versus active control. Evidence quality for CBT outcomes ranged from moderate to low. We rated evidence for AEs as very low quality for both comparisons. BT We analysed eight studies (647 participants). We found no evidence of difference between BT and active control at treatment end (pain SMD -0.67, 95% CI -2.54 to 1.20, very low-quality evidence; disability SMD -0.65, 95% CI -1.85 to 0.54, very low-quality evidence; or distress SMD -0.73, 95% CI -1.47 to 0.01, very low-quality evidence). At follow-up, effects were similar. We found no evidence of difference between BT and TAU (pain SMD -0.08, 95% CI -0.33 to 0.17, low-quality evidence; disability SMD -0.02, 95% CI -0.24 to 0.19, moderate-quality evidence; distress SMD 0.22, 95% CI -0.10 to 0.54, low-quality evidence) at treatment end. At follow-up, we found one to three studies with no evidence of difference between BT and TAU. We rated evidence for all BT versus active control outcomes as very low quality; for BT versus TAU. Evidence quality ranged from moderate to very low. We rated evidence for AEs as very low quality for BT versus active control. No studies of BT versus TAU reported AEs. ACT We analysed five studies (443 participants). There was no evidence of difference between ACT and active control for pain (SMD -0.54, 95% CI -1.20 to 0.11, very low-quality evidence), disability (SMD -1.51, 95% CI -3.05 to 0.03, very low-quality evidence) or distress (SMD -0.61, 95% CI -1.30 to 0.07, very low-quality evidence) at treatment end. At follow-up, there was no evidence of effect for pain or distress (both very low-quality evidence), but two studies showed a large benefit for reducing disability (SMD -2.56, 95% CI -4.22 to -0.89, very low-quality evidence). Two studies compared ACT to TAU at treatment end. Results should be interpreted with caution. We found large benefits of ACT for pain (SMD -0.83, 95% CI -1.57 to -0.09, very low-quality evidence), but none for disability (SMD -1.39, 95% CI -3.20 to 0.41, very low-quality evidence), or distress (SMD -1.16, 95% CI -2.51 to 0.20, very low-quality evidence). Lack of data precluded analysis at follow-up. We rated evidence quality for AEs to be very low. We encourage caution when interpreting very low-quality evidence because the estimates are uncertain and could be easily overturned.

AUTHORS' CONCLUSIONS

We found sufficient evidence across a large evidence base (59 studies, over 5000 participants) that CBT has small or very small beneficial effects for reducing pain, disability, and distress in chronic pain, but we found insufficient evidence to assess AEs. Quality of evidence for CBT was mostly moderate, except for disability, which we rated as low quality. Further trials may provide more precise estimates of treatment effects, but to inform improvements, research should explore sources of variation in treatment effects. Evidence from trials of BT and ACT was of moderate to very low quality, so we are very uncertain about benefits or lack of benefits of these treatments for adults with chronic pain; other treatments were not analysed. These conclusions are similar to our 2012 review, apart from the separate analysis of ACT.