Attempting to Separate Placebo Effects from Exercise in Chronic Pain: A Systematic Review and Meta-analysis

Design of a Health Education Program to Manage Chronic Neck Pain: Protocol for a Development Study

BACKGROUND

Chronic neck pain (CNP) needs attention to its physical, cognitive, and social dimensions.

OBJECTIVE

We aimed to design a health education program (HEP) with a biopsychosocial approach for patients with CNP.

METHODS

A literature search on CNP, health education, and biopsychosocial models was carried out. Seven physiotherapists with expertise in HEPs and chronic pain participated in three teams that evaluated the literature and prepared a synthesis document in relation to the three target topics. Experts compiled the information obtained and prepared a proposal for an HEP with a biopsychosocial approach aimed at patients with CNP. This proposal was tested in the physiotherapy units of primary care health centers belonging to the East Assistance Directorate of Madrid, and suggestions were included in the final program.

RESULTS

The HEP for CNP with a biopsychosocial approach consists of 5 educational sessions lasting between 90 and 120 minutes, carried out every other day. Cognitive, emotional, and physical dimensions were addressed in all sessions, with particular attention to the psychosocial factors associated with people who have CNP.

CONCLUSIONS

The proposed HEP with a biopsychosocial approach emphasizes emotional management, especially stress, without neglecting the importance of physical and recreational exercises for the individual's return to social activities. The objective of this program was to achieve a clinically relevant reduction in perceived pain intensity and functional disability as well as an improvement in quality of life in the short and medium term.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02703506; https://clinicaltrials.gov/study/NCT02703506.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/56632.

The importance of context (placebo effects) in conservative interventions for musculoskeletal pain: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVE

Contextual effects (e.g. patient expectations) may play a role in treatment effectiveness. This study aimed to estimate the magnitude of contextual effects for conservative, non-pharmacological interventions for musculoskeletal pain conditions. A systematic review and meta-analysis of randomized controlled trials (RCTs) that compared placebo conservative non-pharmacological interventions to no treatment for musculoskeletal pain. The outcomes assessed included pain intensity, physical functioning, health-related quality of life, global rating of change, depression, anxiety and sleep at immediate, short-, medium- and/or long-term follow-up.

DATABASES AND DATA TREATMENT

MEDLINE, EMBASE, CINAHL, Web of Science Core Collection, CENTRAL and SPORTDiscus were searched from inception to September 2021. Trial registry searches, backward and forward citation tracking and searches for prior systematic reviews were completed. The Cochrane risk of bias 2 tool was implemented.

RESULTS

The study included 64 RCTs (N = 4314) out of 8898 records. For pain intensity, a mean difference of (MD: -5.32, 95% confidence interval (CI): -7.20, -3.44, N = 57 studies with 74 outcomes, GRADE: very low) was estimated for placebo interventions. A small effect in favour of the placebo interventions for physical function was estimated (SMD: -0.22, 95% CI: -0.35, -0.09; N = 37 with 48 outcomes, GRADE: very low). Similar results were found for a broad range of patient-reported outcomes. Meta-regression analyses did not explain heterogeneity among analyses.

CONCLUSION

The study found that the contextual effect of non-pharmacological conservative interventions for musculoskeletal conditions is likely to be small. However, given the known effect sizes of recommended evidence-based treatments for musculoskeletal conditions, it may still contribute an important component.

SIGNIFICANCE

Contextual effects of non-pharmacological conservative interventions for musculoskeletal conditions are likely to be small for a broad range of patient-reported outcomes (pain intensity, physical function, quality of life, global rating of change and depression). Contextual effects are unlikely, in isolation, to offer much clinical care. But these factors do have relevance in an overall treatment context as they provide almost 30% of the minimally clinically important difference.

Oxytocin Modulation in Mindfulness-Based Pain Management for Chronic Pain

In the context of chronic pain management, opioid-based treatments have been heavily relied upon, raising concerns related to addiction and misuse. Non-pharmacological approaches, such as Mindfulness-Based Pain Management, offer alternative strategies. We conducted a mechanistic clinical study to investigate the impact of an 8-week Mindfulness-Based Pain Management intervention on chronic pain, the modulation of inflammatory markers, stress physiology, and oxytocin, and their interplay with clinical pain symptoms and perception, in comparison to a patient wait-list active control. A total of 65 participants, including 50 chronic pain patients and 15 healthy controls, underwent salivary assays to assess endocrine markers, oxytocin, interleukin (IL)-1b, IL-6, IL-8, tumor necrosis factor (TNF)-a, and dehydroepiandrosterone sulphate (DHEA-S). Psychological assessments were also conducted to evaluate aspects of pain perception, mindfulness, mood, and well-being. Findings revealed significant differences between chronic pain patients and healthy controls in various clinical metrics, highlighting the psychological distress experienced by patients. Following Mindfulness-Based Pain Management, oxytocin levels significantly increased in chronic pain patients, that was not observed in the patient wait-list control group. In contrast, cytokine and DHEA-S levels decreased (not to statistically significant margins) supporting anti-inflammatory effects of Mindfulness-Based Pain Management. The fact DHEA-S levels, a marker of stress, did attenuate but not to statistically meaningful levels, suggests that pain reduction was not solely related to stress reduction, and that oxytocin pathways may be more salient than previously considered. Psychological assessments demonstrated substantial improvements in pain perception and mood in the intervention group. These results contribute to the growing body of evidence regarding the effectiveness of mindfulness-based interventions in chronic pain management and underscore oxytocin's potential role as a therapeutic target.

Understanding how therapeutic exercise prescription changes outcomes important to patients with persistent non-specific low back pain: a realist review protocol

INTRODUCTION

Persistent low back pain (LBP) is the leading cause of disability worldwide, and therapeutic exercise is recommended as a first-line treatment in international guidelines. The effects of exercise on clinical outcomes of pain and physical function are small to moderate, despite broader impacts on cardiovascular systems, biological health, mood, and emotional well-being. Therapeutic exercise prescription is defined as exercise that is prescribed by a clinician for a health-related treatment. It is unknown how therapeutic exercise prescription creates effects on outcomes of importance. Realist reviews explore how underlying mechanisms (M) may be active in the context (C) of certain situations, settings, or populations to create an intended or unintended outcome (O). Our objective is to explore and understand the mechanisms by which therapeutic exercise prescription changes outcomes for people with persistent LBP.

METHODS

We will develop initial programme theories based on preliminary data from a previous systematic review and consensus workshop. These theories will be modified with input from a steering group (experts), a stakeholder group (people with lived experience of exercise for persistent LBP and clinicians), and a scoping search of the published literature. An information specialist will design and undertake an iterative search strategy. These will be used to create CMO configurations, which will be refined and tested using the literature. The realist review will be reported following RAMESES guidance.

DISCUSSION

Realist reviews are uncommon in LBP research to date, yet those offer an opportunity to contrast with traditional methods of randomised controlled trials and systematic reviews and provide additional information regarding the contexts and mechanisms that may trigger certain outcomes. This can aid our understanding of the contextual features that may influence exercise prescription, such as for whom they are most effective, in what setting, how they are implemented and why. This realist synthesis will enhance our understanding of therapeutic exercise prescription to improve adherence and engagement and ultimately will provide clinically relevant recommendations regarding exercise prescription for those with persistent LBP.

SYSTEMATIC REVIEW REGISTRATION

The review has been registered with PROSPERO (CRD42017072023).

The Placebo Effect in Exercise and Mental Health Research

This chapter describes the placebo effect in the context of physical activity and mental health. Following a brief historical overview, definitions for placebos, placebo effects, and related terminology are discussed. Next, three major methodological challenges posed from studying the placebo effect in the context of exercise are described. Additionally, the role of a primary psychological mechanism of placebo and nocebo effects - expectations - will be summarized through the lens of key terminology. Findings from relevant chronic and acute exercise studies that have measured or manipulated exercise-associated expectations will be presented. The chapter concludes with recommendations for controlling or quantifying the placebo effect in exercise and mental health research and its implications in clinical practice.

Current and future advances in practice: tendinopathies of the shoulder

Tendinopathies of the shoulder are a burdensome problem. Current treatments include exercise, physical therapies, corticosteroid injections and surgery. However, the clinical outcomes from randomized controlled trials evaluating the effectiveness of these interventions are largely unremarkable. Given the apparent lack of progress in improving clinical outcomes for patients, it is appropriate to consider other avenues. Research has identified a link between lifestyle-related modifiable risk factors, including smoking, overweight and physical inactivity, and the onset and persistence of tendinopathies of the shoulder. Further research is required to understand whether addressing these factors results in better clinical outcomes for patients. Teachable moments and shared decision-making are concepts that could enable clinicians to integrate the assessment and management of these lifestyle factors. Given that these lifestyle factors also increase the risk of developing other common morbidities, including cardiovascular disease, an evolution of routine clinical care in this way could represent an important step forwards.

Pain catastrophising and kinesiophobia mediate pain and physical function improvements with Pilates exercise in chronic low back pain: a mediation analysis of a randomised controlled trial

QUESTION

How much are the reductions in pain intensity and improvements in physical function from Pilates exercise mediated by changes in pain catastrophising and kinesiophobia?

DESIGN

This was a secondary causal mediation analysis of a four-arm randomised controlled trial testing Pilates exercise dosage (once, twice or thrice per week) against a booklet control.

PARTICIPANTS

Two hundred and fifty-five people with chronic low back pain.

DATA ANALYSIS

All analyses were conducted in R software (version 4.1.2) following a preregistered analysis plan. A directed acyclic graph was constructed to identify potential pre-treatment mediator-outcome confounders. For each mediator model, we estimated the intervention-mediator effect, the mediator-outcome effect, the total natural indirect effect (TNIE), the pure natural direct effect (PNDE), and the total effect (TE).

RESULTS

Pain catastrophising mediated the effect of Pilates exercise compared with control on the outcomes pain intensity (TNIE MD -0.21, 95% CI -0.47 to -0.03) and physical function (TNIE MD -0.64, 95% CI -1.20 to -0.18). Kinesiophobia mediated the effect of Pilates exercise compared with control on the outcomes pain intensity (TNIE MD -0.31, 95% CI -0.68 to -0.02) and physical function (TNIE MD -1.06, 95% CI -1.70 to -0.49). The proportion mediated by each mediator was moderate (21 to 55%).

CONCLUSION

Reductions in pain catastrophising and kinesiophobia partially mediated the pathway to improved pain intensity and physical function when using Pilates exercise for chronic low back pain. These psychological components may be important treatment targets for clinicians and researchers to consider when prescribing exercise for chronic low back pain.

Best Exercise Options for Reducing Pain and Disability in Adults With Chronic Low Back Pain: Pilates, Strength, Core-Based, and Mind-Body. A Network Meta-analysis

OBJECTIVE

To determine which type of exercise is best for reducing pain and disability in adults with chronic low back pain (LBP).

DESIGN

Systematic review with a network meta-analysis (NMA) of randomized controlled trials (RCTs).

LITERATURE SEARCH

Six electronic databases were systematically searched from inception to July 2021.

STUDY SELECTION CRITERIA

RCTs testing the effects of exercise on reducing self-perceived pain or disability in adults (aged 18-65 years) with chronic LBP.

DATA SYNTHESIS

We followed the PRISMA-NMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses, incorporating NMAs of health care interventions) statement when reporting our NMA. A frequentist NMA was conducted. The probability of each intervention being the most effective was conducted according to surface under the cumulative ranking curve (SUCRA) values.

RESULTS

We included 118 trials (9710 participants). There were 28 head-to-head comparisons, 7 indirect comparisons for pain, and 8 indirect comparisons for disability. Compared with control, all types of physical exercises were effective for improving pain and disability, except for stretching exercises (for reducing pain) and the McKenzie method (for reducing disability). The most effective interventions for reducing pain were Pilates, mind-body, and core-based exercises. The most effective interventions for reducing disability were Pilates, strength, and core-based exercises. On SUCRA analysis, Pilates had the highest likelihood for reducing pain (93%) and disability (98%).

CONCLUSION

Although most exercise interventions had benefits for managing pain and disability in chronic LBP, the most beneficial programs were those that included (1) at least 1 to 2 sessions per week of Pilates or strength exercises; (2) sessions of less than 60 minutes of core-based, strength, or mind-body exercises; and (3) training programs from 3 to 9 weeks of Pilates and core-based exercises. J Orthop Sports Phys Ther 2022;52(8):505-521. Epub: 19 June 2022. doi:10.2519/jospt.2022.10671.

Protection motivation theory screening tool for predicting chronic low back pain rehabilitation adherence: analysis of a randomised controlled trial

OBJECTIVE

To explore a protection motivation theory screening tool for predicting rehabilitation adherence.

DESIGN

Analysis of a randomised controlled trial.

SETTING

An exercise physiology and physiotherapist clinic.

PARTICIPANTS

Patients with chronic low back pain (n=40).

INTERVENTIONS

General strength and conditioning (GSC) compared with motor control and manual therapy. Primary and secondary outcome measures: predicting patient adherence to supervised sessions and dropout using the Sports Injury Rehabilitation Beliefs Scale, seven-item barriers checklist and Positive and Negative Affect Schedule and Sports Injury Rehabilitation Adherence Scale.

RESULTS

Average attendance was 77% (motor control and manual therapy) and 60% (GSC) with eight dropouts. No Sports Injury Rehabilitation Adherence Scale values other than 5 across all three components were recorded. Treatment efficacy (p=0.019), self-efficacy (p=0.001), rehabilitation value (p=0.028) and injury severity (p=0.002) positively correlated with susceptibility (the extent of vulnerability to having health problems from not taking action). Rehabilitation value positively correlated with self-efficacy (p=0.005). Injury severity positively correlated with rehabilitation value (p=0.011). The final model for number of cancellations included rehabilitation value only and accounted for approximately 12% of variance (p=0.033).

CONCLUSIONS

Perceived value of rehabilitation should be considered by clinicians in the rehabilitation setting to improve treatment adherence in patients with chronic low back pain.

TRIAL REGISTRATION NUMBER

ACTRN12615001270505.

The importance of selecting the correct site to apply spinal manipulation when treating spinal pain: Myth or reality? A systematic review

The concept that spinal manipulation therapy (SMT) outcomes are optimized when the treatment is aimed at a clinically relevant joint is commonly assumed and central to teaching and clinical use (candidate sites). This systematic review investigated whether clinical effects are superior when this is the case compared to SMT applied elsewhere (non-candidate sites). Eligible study designs were randomized controlled trials that investigated the effect of spinal manipulation applied to candidate versus non-candidate sites for spinal pain. We obtained data from four different databases. Risk of bias was assessed using an adjusted Cochrane risk of bias tool, adding four items for study quality. We extracted between-group differences for any reported outcome or, when not reported, calculated effect sizes from the within-group changes. We compared outcomes for SMT applied at a 'relevant' site to SMT applied elsewhere. We prioritized methodologically robust studies when interpreting results. Ten studies, all of acceptable quality, were included that reported 33 between-group differences-five compared treatments within the same spinal region and five at different spinal regions. None of the nine studies with low or moderate risk of bias reported statistically significant between-group differences for any outcome. The tenth study reported a small effect on pain (1.2/10, 95%CI - 1.9 to - 0.5) but had a high risk of bias. None of the nine articles of low or moderate risk of bias and acceptable quality reported that "clinically-relevant" SMT has a superior outcome on any outcome compared to "not clinically-relevant" SMT. This finding contrasts with ideas held in educational programs and clinical practice that emphasize the importance of joint-specific application of SMT.