NIH's Helping to End Addiction Long-termSM Initiative (NIH HEAL Initiative) Clinical Pain Management Common Data Element Program

Clinical and biobehavioral phenotypic assessments and data harmonization for the RE-JOIN research consortium: Recommendations for common data element selection

Background

The Restoring Joint Health and Function to Reduce Pain (RE-JOIN) Consortium is part of the Helping to End Addiction Long-term® (HEAL) Initiative. HEAL is an ambitious, NIH-wide initiative to speed scientific solutions to stem the national opioid public health crisis. The RE-JOIN consortium's over-arching goal is to define how chronic joint pain-mediating neurons innervate different articular and peri-articular tissues, with a focus on the knee and temporomandibular joints (TMJ) across species employing the latest neuroscience approaches. The aim of this manuscript is to elucidate the human data gathered by the RE-JOIN consortium, as well as to expound upon its underlying rationale and the methodologies and protocols for harmonization and standardization that have been instituted by the RE-JOIN Consortium.

Methods

The consortium-wide human models working subgroup established the RE-JOIN minimal harmonized data elements that will be collected across all human studies and set the stage to develop parallel pre-clinical data collection standards. Data harmonization considerations included requirements from the HEAL program and recommendations from the consortium's researchers and experts on informatics, knowledge management, and data curation.

Results

Multidisciplinary experts - including preclinical and clinical researchers, with both clinician-scientists- developed the RE-JOIN's Minimal Human Data Standard with required domains and outcome measures to be collected across projects and institutions. The RE-JOIN minimal data standard will include HEAL Common Data Elements (CDEs) (e.g., standardized demographics, general pain, psychosocial and functional measures), and RE-JOIN common data elements (R-CDE) (i.e., both general and joint-specific standardized and clinically important self-reported pain and function measures, as well as pressure pain thresholds part of quantitative sensory testing). In addition, discretionary, site-specific measures will be collected by individual institutions (e.g., expanded quantitative sensory testing and gait biomechanical assessments), specific to the knee or TMJ. Research teams will submit datasets of standardized metadata to the RE-JOIN Data Coordinating Center (DCG) via a secure cloud-based central data repository and computing infrastructure for researchers to share and conduct analyses on data collected by or acquired for RE-JOIN. RE-JOIN datasets will have protected health information (PHI) removed and be publicly available on the SPARC portal and accessible through the HEAL Data Ecosystem.

Conclusion

Data Harmonization efforts provide the multidisciplinary consortium with an opportunity to effectively collaborate across decentralized research teams, and data standardization sets the framework for efficient future analyses of RE-JOIN data collected by the consortium. The harmonized phenotypic information obtained will significantly enhance our understanding of the neurobiology of the pain-pathology relationships in humans, providing valuable insights for comparison with pre-clinical models.

Topical Ophthalmic Anesthetics for CornealAbrasions: Findings from a Cochrane SystematicReview and Meta-Analysis

Background

Despite potential benefit, outpatient use of topical ophthalmic anesthetics can result in poor healing, infection, scar, and blindness. An unbiased analysis of randomized controlled trials (RCTs) is needed to examine their effectiveness and safety compared with placebo or other treatments for corneal abrasions.

Methods

Cochrane Central Register of Controlled Trials, MEDLINE, Embase.com, Latin American and Caribbean Health Sciences, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform were searched on February 10, 2023, without restriction on language or publication date.

Results

Systematic review and meta-analysis of nine RCTs describing 314 participants with post-traumatic abrasions and 242 participants with post-surgical abrasions, with a median study length of 7 days (interquartile range, 7-14), show no evidence of a difference in pain control between anesthetics and placebo at 24 hours in post-trauma cases. Self-reported pain at 24 hours is reduced with anesthetics plus topical nonsteroid anti-inflammatory drug in post-surgical participants (mean difference [MD], -5.72 on a 10-point scale; 95% CI, -7.35 to -4.09; 1 RCT; 30 participants) and at 48 hours with anesthetics alone in post-trauma participants (MD, -5.68; 95% CI, -6.38 to -4.98; 1 RCT; 111 participants). Anesthetics are associated with 37% increased risk of non-healing defects (risk ratio, 1.37; 95% CI, 0.78 to 2.42; 3 RCTs; 221 post-trauma participants). All evidence is of very low certainty. Over 50% of trials have an overall high risk of bias.

Conclusions

Available evidence is insufficient to support outpatient use of topical anesthetics for corneal abrasions with respect to pain, re-epithelialization, and complication risk.

Neuroma Analysis in Humans: Standardizing Sample Collection and Documentation

INTRODUCTION

The biology of symptomatic neuromas is poorly understood, particularly the factors causing pain in human neuromas. Pain presence varies among and within individuals, with some having painful and nonpainful neuromas. To bridge these knowledge gaps, our group developed a protocol for assessing neuroma pain and collecting tissue for molecular analysis. This manuscript outlines our workflow and challenges and aims to inspire other centers to share their experiences with these tissues.

METHODS

For every included patient and collected nerve or bone tissue specimens, we perform a detailed chart review and a multifaceted analysis of pain and pain perception immediately before surgery. We collect patient-reported outcome measures (PROMs) on pain, function, and mental well-being outcomes at preoperative assessment and at the 6-month follow-up postoperatively. Before surgery, the patient is assessed once again to obtain an immediate preoperative pain status and identify potential differences in pain intensity of different neuromas. Intraoperatively, specimens are obtained and their gross anatomical features are recorded, after which they are stored in paraformaldehyde or frozen for later sample analyses. Postoperatively, patients are contacted to obtain additional postoperative PROMs.

RESULTS

A total of 220 specimens of nerve tissue have been successfully obtained from 83 limbs, comprising 95 specimens of neuromas and 125 specimens of nerves located proximal to the neuromas or from controls.

CONCLUSIONS

Our approach outlines the methods combining specimen collection and examination, including both macroscopic and molecular biological features, with PROMs, encompassing physical and psychological aspects, along with clinical metadata obtained through clinical teams and chart review.

Priorities for HIV and chronic pain research: results from a survey of individuals with lived experience

The Global Task Force on Chronic Pain in HIV published seven research priorities in the field of HIV-associated chronic pain in 2019: (1) causes; (2) management; (3) treatment individualization and integration with addiction treatment; (4) mental and social health factors; (5) prevalence; (6) treatment cost effectiveness; and (7) prevention. The current study used a web-based survey to determine whether the research topics were aligned with the priorities of adults with lived experiences of HIV and chronic pain. We also collected information about respondents' own pain and treatment experiences. We received 311 survey responses from mostly US-based respondents. Most respondents reported longstanding, moderate to severe, multisite pain, commonly accompanied by symptoms of anxiety and/or depression. The median number of pain treatments tried was 10 (IQR = 8, 13), with medications and exercise being the most common modalities, and opioids being viewed as the most helpful. Over 80% of respondents considered all research topics either "extremely important" or "very important". Research topic #2, which focused on optimizing management of pain in people with HIV, was accorded the greatest importance by respondents. These findings suggest good alignment between the priorities of researchers and US-based people with lived experience of HIV-associated chronic pain.

Integrating randomized and observational studies to estimate optimal dynamic treatment regimes

Sequential multiple assignment randomized trials (SMARTs) are the gold standard for estimating optimal dynamic treatment regimes (DTRs), but are costly and require a large sample size. We introduce the multi-stage augmented Q-learning estimator (MAQE) to improve efficiency of estimation of optimal DTRs by augmenting SMART data with observational data. Our motivating example comes from the Back Pain Consortium, where one of the overarching aims is to learn how to tailor treatments for chronic low back pain to individual patient phenotypes, knowledge which is lacking clinically. The Consortium-wide collaborative SMART and observational studies within the Consortium collect data on the same participant phenotypes, treatments, and outcomes at multiple time points, which can easily be integrated. Previously published single-stage augmentation methods for integration of trial and observational study (OS) data were adapted to estimate optimal DTRs from SMARTs using Q-learning. Simulation studies show the MAQE, which integrates phenotype, treatment, and outcome information from multiple studies over multiple time points, more accurately estimates the optimal DTR, and has a higher average value than a comparable Q-learning estimator without augmentation. We demonstrate this improvement is robust to a wide range of trial and OS sample sizes, addition of noise variables, and effect sizes.

Connecting Chronic Pain and Opioid Use Disorder Clinical Trials Through Data Harmonization: Wake Forest IMPOWR Dissemination, Education, and Coordination Center (IDEA-CC)

The National Institutes of Health (NIH) has developed the NIH HEAL Integrative Management of chronic Pain and OUD for Whole Recovery (IMPOWR) network to address the interconnected nature of chronic pain (CP) and opioid use disorder (OUD), which are influenced by mental health. The network aims to develop integrated treatment pathways across multiple sites in the United States. The IMPOWR Dissemination, Education, and Coordination Center (IDEA-CC) is proposed to support the NIH HEAL IMPOWR network by developing a CP- and OUD-focused infrastructure that includes measures of stigma, trauma, and quality of life. This includes deploying a data framework to link clinical sites, developing an educational infrastructure to address stigma and health disparities, and disseminating research findings. The IDEA-CC will standardize data collection processes, develop web-based data commons, and facilitate data sharing opportunities. The IDEA-CC will support the development and validation of composite CP and OUD measures and will develop educational materials to address stigma and health disparities. Overall, the IDEA-CC will create a research community and data commons that connect NIH HEAL IMPOWR centers to translate findings and develop a key CP-OUD research data, and education infrastructure.

Mobile health intervention to address chronic pain among those who engage in hazardous drinking: A pilot study

BACKGROUND

Hazardous drinking has been associated with chronic pain in community and medical samples. The purpose of this study was to develop a novel, integrated mobile health intervention that improves pain management and reduces hazardous drinking that may be implemented in primary care settings.

METHODS

Forty-eight participants with moderate or greater chronic pain and hazardous drinking were recruited from primary care clinics and through social media sites. Following baseline assessment, participants were randomized to a counselor-supported smartphone app intervention (INTV) or a counselor delivered treatment-as-usual control condition (CTL).

RESULTS

Results supported the feasibility and acceptability of the smartphone app intervention. Participants found it easy to use, reported high levels of satisfaction, and showed high levels of engagement with the app. Between-group effect size estimates at follow-up showed small effects for the intervention on pain ratings. However, using clinically meaningful change thresholds of 30% and 50% improvement in pain scores, 38% and 25% respectively of those in the INTV condition showed reductions compared to 20% and 12.5% respectively in the CTL condition. Effect size estimates did not indicate intervention superiority on alcohol outcomes as participants in both conditions showed considerable reductions in drinking over the course of the study.

CONCLUSIONS

Results supported the view that a mobile health intervention delivered via smartphone with electronic coaching is a feasible and acceptable method of addressing chronic pain among those who engage in hazardous drinking. Future work should test the efficacy of this approach in a fully powered trial.

Monitoring and responding to signals of suicidal ideation in pragmatic clinical trials: Lessons from the GRACE trial for Chronic Sickle Cell Disease Pain

Sickle cell disease (SCD) is a hemoglobin disorder and the most common genetic disorder that affects 100,000 Americans and millions worldwide. Adults living with SCD have pain so severe that it often requires opioids to keep it in control. Depression is a major global public health concern associated with an increased risk in chronic medical disorders, including in adults living with sickle cell disease (SCD). A strong relationship exists between suicidal ideation, suicide attempts, and depression. Researchers enrolling adults living with SCD in pragmatic clinical trials are obligated to design their methods to deliberately monitor and respond to symptoms related to depression and suicidal ideation. This will offer increased protection for their participants and help clinical investigators meet their fiduciary duties. This article presents a review of this sociotechnical milieu that highlights, analyzes, and offers recommendations to address ethical considerations in the development of protocols, procedures, and monitoring activities related to suicidality in depressed patients in a pragmatic clinical trial.

Measures of sleep disturbance are not routinely captured in trials for chronic low back pain: a systematic scoping review of 282 trials

STUDY OBJECTIVES

To investigate the extent to which sleep measures are reported in intervention trials for chronic low back pain.

METHODS

A systematic scoping review was conducted. Ovid MEDLINE, Cochrane CENTRAL, and CINAHL were queried for trials published between January 2010 and December 2022 using keywords related to chronic low back pain. Two reviewers screened and reviewed abstracts and full texts for eligibility criteria and extracted data. Randomized intervention trials with the aim to treat pain or disability related to chronic low back pain in adults were included. Data were pooled and synthesized from trials that included a measure of sleep.

RESULTS

Two hundred eighty-two trials conducted in 40 different countries were included in the final review. Twenty-six trials (9.2%) assessed any sleep measure, and 13 (4.6%) collected a formal sleep disturbance measure at multiple time points. Three trials analyzed the mediating effects of sleep disturbance on pain. Reporting of sleep measures was no better in more recently published trials; trials published in 2010 (22%; n = 2/9) and 2022 (23%; n = 3/13) had the highest reporting rates.

CONCLUSIONS

The poor adherence to guideline recommendations for capturing measures of sleep quality or disturbance limits clinicians' and researchers' understanding of how sleep may influence treatment effects for chronic low back pain. There is an opportunity to improve the understanding of the relationship between sleep and pain with improved collection and reporting of sleep disturbance measures.

CITATION

Neilson BD, Dickerson C, Young JL, Shepherd MH, Rhon DI. Measures of sleep disturbance are not routinely captured in trials for chronic low back pain: a systematic scoping review of 282 trials. J Clin Sleep Med. 2023;19(11):1961-1970.

Biobehavioral Assessments in BACPAC: Recommendations, Rationale, and Methods

The Biobehavioral Working Group of BACPAC was charged to evaluate a range of psychosocial, psychophysical, and behavioral domains relevant to chronic low back pain, and recommend specific assessment tools and procedures to harmonize biobehavioral data collection across the consortium. Primary references and sources for measure selection were the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials, the Minimum Data Set from the National Institutes of Health (NIH) Research Task Force on Standards for Chronic Low Back Pain, the Patient-Reported Outcomes Measurement Information System, and NeuroQOL. The questionnaire's recommendations supplemented the NIH HEAL Common Data Elements and BACPAC Minimum Data Set. Five domains were identified for inclusion: Pain Characteristics and Qualities; Pain-Related Psychosocial/Behavioral Factors; General Psychosocial Factors; Lifestyle Choices; and Social Determinants of Health/Social Factors. The Working Group identified best practices for required and optional Quantitative Sensory Testing of psychophysical pain processing for use in BACPAC projects.

The Back Pain Consortium (BACPAC) Research Program Data Harmonization: Rationale for Data Elements and Standards

OBJECTIVE

One aim of the Back Pain Consortium (BACPAC) Research Program is to develop an integrated model of chronic low back pain that is informed by combined data from translational research and clinical trials. We describe efforts to maximize data harmonization and accessibility to facilitate Consortium-wide analyses.

METHODS

Consortium-wide working groups established harmonized data elements to be collected in all studies and developed standards for tabular and nontabular data (eg, imaging and omics). The BACPAC Data Portal was developed to facilitate research collaboration across the Consortium.

RESULTS

Clinical experts developed the BACPAC Minimum Dataset with required domains and outcome measures to be collected by use of questionnaires across projects. Other nonrequired domain-specific measures are collected by multiple studies. To optimize cross-study analyses, a modified data standard was developed on the basis of the Clinical Data Interchange Standards Consortium Study Data Tabulation Model to harmonize data structures and facilitate integration of baseline characteristics, participant-reported outcomes, chronic low back pain treatments, clinical exam, functional performance, psychosocial characteristics, quantitative sensory testing, imaging, and biomechanical data. Standards to accommodate the unique features of chronic low back pain data were adopted. Research units submit standardized study data to the BACPAC Data Portal, developed as a secure cloud-based central data repository and computing infrastructure for researchers to access and conduct analyses on data collected by or acquired for BACPAC.

CONCLUSIONS

BACPAC harmonization efforts and data standards serve as an innovative model for data integration that could be used as a framework for other consortia with multiple, decentralized research programs.

The Effectiveness of a Mindfulness-Based Intervention Integrated with Physical Therapy (MIND-PT) for Postsurgical Rehabilitation After Lumbar Surgery: A Protocol for a Randomized Controlled Trial as Part of the Back Pain Consortium (BACPAC) Research Program

BACKGROUND

Improving pain management for persons with chronic low back pain (LBP) undergoing surgery is an important consideration in improving patient-centered outcomes and reducing the risk of persistent opioid use after surgery. Nonpharmacological treatments, including physical therapy and mindfulness, are beneficial for nonsurgical LBP through complementary biopsychosocial mechanisms, but their integration and application for persons undergoing surgery for LBP have not been examined. This study (MIND-PT) is a multisite randomized trial that compares an enriched pain management (EPM) pathway that integrates physical therapy and mindfulness vs usual-care pain management (UC) for persons undergoing surgery for LBP.

DESIGN

Participants from military treatment facilities will be enrolled before surgery and individually randomized to the EPM or UC pain management pathways. Participants assigned to EPM will receive presurgical biopsychosocial education and mindfulness instruction. After surgery, the EPM group will receive 10 sessions of physical therapy with integrated mindfulness techniques. Participants assigned to the UC group will receive usual pain management care after surgery. The primary outcome will be the pain impact, assessed with the Pain, Enjoyment, and General Activity (PEG) scale. Time to opioid discontinuation is the main secondary outcome.

SUMMARY

This trial is part of the National Institutes of Health Helping to End Addiction Long-term (HEAL) initiative, which is focused on providing scientific solutions to the opioid crisis. The MIND-PT study will examine an innovative program combining nonpharmacological treatments designed to improve outcomes and reduce opioid overreliance in persons undergoing lumbar surgery.

NIH HEAL Clinical Data Elements (CDE) implementation: NIH HEAL Initiative IMPOWR network IDEA-CC

OBJECTIVE

The National Institutes of Health (NIH) HEAL Initiative is making data findable, accessible, interoperable, and reusable (FAIR) to maximize the value of the unprecedented federal investment in pain and opioid-use disorder research. This involves standardizing the use of common data elements (CDE) for clinical research.

METHODS

This work describes the process of the selection, processing, harmonization, and design constraints of CDE across a pain and opioid use disorder clinical trials network (NIH HEAL IMPOWR).

RESULTS

The network alignment allowed for incorporation of newer data standards across the clinical trials. Specific advances included geographic coding (RUCA), deidentified patient identifiers (GUID), shareable clinical survey libraries (REDCap), and concept mapping to standardized concepts (UMLS).

CONCLUSIONS

While complex, harmonization across a network of chronic pain and opioid use disorder clinical trials with separate interventions can be optimized through use of CDEs and data standardization processes. This standardization process will support the robust secondary data analyses. Scaling this process could standardize CDE results across interventions or disease state which could help inform insurance companies or government organizations about coverage determinations. The development of the HEAL CDE program supports connecting isolated studies and solutions to each other, but the practical aspects may be challenging for some studies to implement. Leveraging tools and technology to simplify process and create ready to use resources may support wider adoption of consistent data standards.

Effect of Risk-Stratified Care on Disability Among Adults With Low Back Pain Treated in the Military Health System: A Randomized Clinical Trial

Importance

Tailored treatments for low back pain (LBP) based on stratifying risk for poor prognosis have emerged as a promising approach to improve quality of care, but they have not been validated in trials at the level of individual randomization in US health systems.

Objective

To assess the clinical effectiveness of risk-stratified vs usual care on disability at 1 year among patients with LBP.

Design, Setting, and Participants

This parallel-group randomized clinical trial enrolled adults (ages 18-50 years) seeking care for LBP with any duration in primary care clinics within the Military Health System from April 2017 to February 2020. Data analysis was conducted from January to December 2022.

Interventions

Risk-stratified care, in which participants received physiotherapy treatment tailored for their risk category (low, medium, or high), or usual care, in which care was determined by participants' general practitioners and may have included a referral to physiotherapy.

Main Outcomes and Measures

The primary outcome was the Roland Morris Disability Questionnaire (RMDQ) score at 1 year, with planned secondary outcomes of Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference (PI) and Physical Function (PF) scores. Raw downstream health care utilization was also reported within each group.

Results

Analysis included 270 participants (99 [34.1%] female participants; mean [SD] age, 34.1 [8.5] years). Only 21 patients (7.2%) were classified as high risk. Neither group was superior on the RMDQ (least squares [LS] mean ratio of risk-stratified vs usual care: 1.00; 95% CI, 0.80 to 1.26), the PROMIS PI (LS mean difference, -0.75 points; 95% CI -2.61 to 1.11 points), or the PROMIS PF (LS mean difference, 0.05 points; 95% CI, -1.66 to 1.76 points).

Conclusions and Relevance

In this randomized clinical trial, using risk stratification to categorize and provide tailored treatment for patients with LBP did not result in better outcomes at 1 year compared with usual care.

Trial Registration

ClinicalTrials.gov Identifier: NCT03127826.

Targets and study design for symptom-focused trials aimed at patients with cirrhosis: An expert consensus

BACKGROUND

Symptom-focused trials are critically needed for patients with cirrhosis. However, this work would benefit from standard processes and validated measures.

METHODS

A writing group was formed among hepatologists, nurses, palliative care providers, pharmacists, and clinical trial experts focused on symptom management in patients with cirrhosis to define the key (1) components of trial design, (2) symptom targets, (3) measurement, and (4) outcomes for each target. From July 2022 to January 2023, panelists participated in an iterative process of developing and arriving at a consensus for each component. The goal was to provide consensus definitions that can be operationalized in future clinical trials, including for patients with cirrhosis.

RESULTS

The panel reached a consensus on key reporting features for clinical trials, along with considerations for study design. Nine key symptom targets (muscle cramps, pruritus, pain, fatigue, sexual dysfunction, sleep disorders, depression and anxiety, nausea/vomiting, and dyspnea/breathlessness) were identified. The panel selected instruments that can be considered for clinical trials based on psychometric validation and previous experience. The panel identified ongoing needs, including instrument validation, safety data, evidence about non-pharmacologic interventions, and comparative effectiveness studies.

CONCLUSION

This expert panel identified key design, reporting, and measurement elements to standardize processes and measures in future symptom-focused clinical trials in the context of cirrhosis.

Hybrid effectiveness-implementation trial of guided relaxation and acupuncture for chronic sickle cell disease pain (GRACE): A protocol

Background

People with sickle cell disease frequently use complementary and integrative therapies to cope with their pain, yet few studies have evaluated their effectiveness. The 3-arm, 3-site pragmatic Hybrid Effectiveness-implementation Trial of Guided Relaxation and Acupuncture for Chronic Sickle Cell Disease Pain (GRACE) has 3 priorities: (1) evaluate guided relaxation and acupuncture to improve pain control; (2) determine the most appropriate and effective treatment sequence for any given patient based on their unique characteristics; and (3) describe the processes and structures required to implement guided relaxation and acupuncture within health care systems.

Methods

Participants (N = 366) are being recruited and randomized 1:1:1 to one of 2 intervention groups or usual care. The acupuncture intervention group receives 10 sessions over approximately 5 weeks. The guided relaxation intervention group receives access to video sessions ranging from 2 to 20 min each viewed daily over 5 weeks. The usual care group receives the standard of clinical care for sickle cell disease. Participants are re-randomized at 6 weeks depending on their pain impact score. Assessments occur at 6 weeks, 12 weeks, and 24 weeks. The primary outcome is the change in pain impact score and secondary measures include opioid use, anxiety, depression, sleep, pain catastrophizing, substance use, global impression of change, constipation, and hospitalizations. The GRACE study uses the Consolidated Framework for Implementation Research to plan, execute, and evaluate the associated implementation processes.

Conclusion

The results from GRACE will represent a critical step toward improving management of pain affecting patients with sickle cell disease.ClinicalTrials.gov Identifier: NCT04906447.

BeatPain Utah: study protocol for a pragmatic randomised trial examining telehealth strategies to provide non-pharmacologic pain care for persons with chronic low back pain receiving care in federally qualified health centers

INTRODUCTION

Although evidence-based guidelines recommend non-pharmacologic treatments as first-line care for chronic low back pain (LBP), uptake has been limited, particularly in rural, low-income and ethnically diverse communities. The BeatPain study will evaluate the implementation and compare the effectiveness of two strategies to provide non-pharmacologic treatment for chronic LBP. The study will use telehealth to overcome access barriers for persons receiving care in federally qualified health centres (FQHCs) in the state of Utah.

METHODS AND ANALYSIS

BeatPain Utah is a pragmatic randomised clinical trial with a hybrid type I design investigating different strategies to provide non-pharmacologic care for adults with chronic LBP seen in Utah FQHCs. The intervention strategies include a brief pain consult (BPC) and telehealth physical therapy (PT) component provided using either an adaptive or sequenced delivery strategy across two 12-week treatment phases. Interventions are provided via telehealth by centrally located physical therapists. The sequenced delivery strategy provides the BPC, followed by telehealth PT in the first 12 weeks for all patients. The adaptive strategy uses a stepped care approach and provides the BPC in the first 12 weeks and telehealth PT to patients who are non-responders to the BPC component. We will recruit 500 English-speaking or Spanish-speaking participants who will be individually randomised with 1:1 allocation. The primary outcome is the Pain, Enjoyment and General Activity measure of pain impact with secondary outcomes including the additional pain assessment domains specified by the National Institutes (NIH) of Health Helping to End Addiction Long Initiative and implementation measures. Analyses of primary and secondary measures of effectiveness will be performed under longitudinal mixed effect models across assessments at baseline, and at 12, 26 and 52 weeks follow-ups.

ETHICS AND DISSEMINATION

Ethics approval for the study was obtained from the University of Utah Institutional Review Board. On completion, study data will be made available in compliance with NIH data sharing policies.

TRIAL REGISTRATION NUMBER

NCT04923334.

Endogenous opioid systems alterations in pain and opioid use disorder

Decades of research advances have established a central role for endogenous opioid systems in regulating reward processing, mood, motivation, learning and memory, gastrointestinal function, and pain relief. Endogenous opioid systems are present ubiquitously throughout the central and peripheral nervous system. They are composed of four families, namely the μ (MOPR), κ (KOPR), δ (DOPR), and nociceptin/orphanin FQ (NOPR) opioid receptors systems. These receptors signal through the action of their endogenous opioid peptides β-endorphins, dynorphins, enkephalins, and nociceptins, respectfully, to maintain homeostasis under normal physiological states. Due to their prominent role in pain regulation, exogenous opioids-primarily targeting the MOPR, have been historically used in medicine as analgesics, but their ability to produce euphoric effects also present high risks for abuse. The ability of pain and opioid use to perturb endogenous opioid system function, particularly within the central nervous system, may increase the likelihood of developing opioid use disorder (OUD). Today, the opioid crisis represents a major social, economic, and public health concern. In this review, we summarize the current state of the literature on the function, expression, pharmacology, and regulation of endogenous opioid systems in pain. Additionally, we discuss the adaptations in the endogenous opioid systems upon use of exogenous opioids which contribute to the development of OUD. Finally, we describe the intricate relationship between pain, endogenous opioid systems, and the proclivity for opioid misuse, as well as potential advances in generating safer and more efficient pain therapies.

Multi-Site Observational Study to Assess Biomarkers for Susceptibility or Resilience to Chronic Pain: The Acute to Chronic Pain Signatures (A2CPS) Study Protocol

Chronic pain has become a global health problem contributing to years lived with disability and reduced quality of life. Advances in the clinical management of chronic pain have been limited due to incomplete understanding of the multiple risk factors and molecular mechanisms that contribute to the development of chronic pain. The Acute to Chronic Pain Signatures (A2CPS) Program aims to characterize the predictive nature of biomarkers (brain imaging, high-throughput molecular screening techniques, or "omics," quantitative sensory testing, patient-reported outcome assessments and functional assessments) to identify individuals who will develop chronic pain following surgical intervention. The A2CPS is a multisite observational study investigating biomarkers and collective biosignatures (a combination of several individual biomarkers) that predict susceptibility or resilience to the development of chronic pain following knee arthroplasty and thoracic surgery. This manuscript provides an overview of data collection methods and procedures designed to standardize data collection across multiple clinical sites and institutions. Pain-related biomarkers are evaluated before surgery and up to 3 months after surgery for use as predictors of patient reported outcomes 6 months after surgery. The dataset from this prospective observational study will be available for researchers internal and external to the A2CPS Consortium to advance understanding of the transition from acute to chronic postsurgical pain.