The objective of this study was to evaluate how enrichment for responders increases assay sensitivity in an enriched enrollment randomized withdrawal (EERW) proof-of-concept (POC) study in neuropathic pain. Adults with moderate to severe peripheral neuropathic pain entered a 3- to 4-day screening period, followed by a 12-day titration to the highest tolerated dose that provided pain control (pregabalin 50-200mg t.i.d.), and then a 9-day maintenance period. Subjects were stratified as primary responders (⩾30%), secondary responders (⩾10% to <30%), or nonresponders (<10%) based on decrease in pain intensity and were randomized to placebo or pregabalin during the randomized withdrawal period. The primary endpoint was mean of average 24-h pain intensity during the last 3days of treatment period relative to the 3days before randomization. Time-to-efficacy-failure was the key secondary endpoint. Other features included not requiring discontinuation of current analgesic therapies and blinding investigators to study design elements that could contribute to non-treatment-related responses. Effect size (ES) (mean treatment difference/SD) was used to measure assay sensitivity. Pregabalin-treated subjects (n=52) had significantly less pain than those receiving placebo (n=51) (P⩽.003). Effect size of the primary endpoint was 0.72 for primary responders and decreased if secondary and nonresponders were included in the analysis. The highest ES (1.68) was demonstrated for the endpoint time-to-efficacy-failure seen in primary responders with painful diabetic neuropathy. The EERW trial design using time-to-efficacy-failure may provide a sensitive and efficient method to conduct POC studies of novel therapies in patients with neuropathic pain. Enriching a study population with patients who have achieved a 30% decrease in pain with an investigational therapy, and using time-to-efficacy-failure during the randomized withdrawal phase as the primary endpoint, can be used for a proof-of-concept study to optimize assay sensitivity and efficiently determine the analgesic potential of a new treatment for neuropathic pain.
Introduction While researchers have studied Hmong patients with limited English proficiency in pain communication, no research has examined primary care providers’ (PCPs’) interpretation of Hmong pain communication. This study examines PCPs’ pain communication experience with Hmong patients. Method A qualitative content analysis was conducted with PCPs. Interviews were audio recorded, transcribed, and analyzed using conventional content analysis. Results Fifteen PCPs—including seven physicians, one osteopathic physician, four nurse practitioners, and three physician assistants—participated. PCPs’ interpretations of pain communication with Hmong patients were characterized by three themes: (a) the providers experienced pain communication problems related to language, (b) the providers perceived the Hmong to have different beliefs about pain, and (c) the providers used different strategies to improve communication. Discussion The findings suggest that challenges are present in achieving effective pain communication between Hmong patients and their PCPs. Ineffective pain communication hinders the delivery of culturally congruent health care for Hmong patients.
ALO-02, comprising pellets of extended-release oxycodone surrounding sequestered naltrexone, is intended to deter abuse.Determine the abuse potential of intravenous oxycodone combined with naltrexone, which represents simulated crushed ALO-02 in solution, compared with intravenous oxycodone in nondependent, recreational opioid users.A randomized, double-blind, placebo-controlled, three-way crossover study with naloxone challenge, drug discrimination, and treatment phases. Intravenous treatments included oxycodone hydrochloride 20 mg, oxycodone hydrochloride 20 mg plus naltrexone hydrochloride 2.4 mg (simulated crushed ALO-02 20 mg/2.4 mg), or placebo (0.9% sodium chloride for injection). Primary end points were peak effects (Emax) and area under the effects curve within 2 h postdose (AUE0-2h) on drug liking and high visual analog scales.Thirty-three participants were randomized into treatment phase, and 29 completed all treatments. Study validity was confirmed with statistically significant differences in Emax for drug liking and high (p < 0.0001) between intravenous oxycodone and placebo. Intravenous simulated crushed ALO-02 resulted in significantly lower scores than oxycodone on drug liking (Emax: 58.2 vs. 92.4; AUE0-2h: 104.3 vs. 152.4) and high (Emax: 17.2 vs. 93.1; AUE0-2h: 12.0 vs. 133.6), respectively (p < 0.0001, all comparisons). More participants experienced adverse events after intravenous oxycodone (n = 27 [90%]) versus intravenous simulated crushed ALO-02 (n = 4 [12.5%]) or placebo (n = 2 [6.5%]).Intravenous administration of simulated crushed ALO-02 resulted in significantly lower abuse potential, as assessed by subjective ratings of drug liking and high, than intravenous oxycodone in nondependent, recreational opioid users. This suggests that injection of ALO-02 may not be as desirable to recreational opioid users compared with oxycodone taken for nonmedical reasons.
Although mindfulness meditation (MM) is increasingly used for chronic pain treatment, limited evidence supports its clinical application for opioid-treated chronic low back pain (CLBP). The goal of this study was to determine feasibility, acceptability, and safety of an MM-based intervention in patients with CLBP requiring daily opioid therapy.26-week pilot randomized controlled trial comparing MM-based intervention, combined with usual care, to usual care alone.Outpatient.Adults with CLBP treated with ≥30 mg of morphine-equivalent dose (MED) per day for 3 months or longer.Targeted MM-based intervention consisted of eight weekly 2-hour group sessions and home practice (30 minutes/d, 6 days/wk) during the study. "Usual care" for opioid-treated CLBP was provided to participants by their regular clinicians.Feasibility and acceptability of the MM intervention were assessed by adherence to intervention protocol and treatment satisfaction among experimental participants. Safety was evaluated by inquiry about side effects/adverse events and opioid dose among all study participants.Thirty-five participants enrolled during the 10-week recruitment period. The mean age (±standard deviation) was 51.8 ± 9.7 years; the patients were predominantly female, with substantial CLBP-related pain and disability, and treated with 148.3 ± 129.2 mg of MED per day. All participants completed baseline assessments; none missed both follow-up assessments or withdrew. Among experimental participants (n = 21), 19 attended 1 or more intervention sessions and 14 attended 4 or more. They reported, on average, 164.0 ± 122.1 minutes of formal practice per week during the 26-week study and 103.5 ± 111.5 minutes of brief, informal practice per week. Seventeen patients evaluated the intervention, indicating satisfaction; their qualitative responses described the course as useful for pain management (n = 10) and for improving pain coping skills (n = 8). No serious adverse events or safety concerns occurred among the study participants.MM-based intervention is feasible, acceptable, and safe in opioid-treated CLBP.
Neuropathic pain (NP) is often refractory to pharmacologic and noninterventional treatment. On behalf of the International Association for the Study of Pain Neuropathic Pain Special Interest Group, the authors evaluated systematic reviews, clinical trials, and existing guidelines for the interventional management of NP. Evidence is summarized and presented for neural blockade, spinal cord stimulation (SCS), intrathecal medication, and neurosurgical interventions in patients with the following peripheral and central NP conditions: herpes zoster and postherpetic neuralgia (PHN); painful diabetic and other peripheral neuropathies; spinal cord injury NP; central poststroke pain; radiculopathy and failed back surgery syndrome (FBSS); complex regional pain syndrome (CRPS); and trigeminal neuralgia and neuropathy. Due to the paucity of high-quality clinical trials, no strong recommendations can be made. Four weak recommendations based on the amount and consistency of evidence, including degree of efficacy and safety, are: 1) epidural injections for herpes zoster; 2) steroid injections for radiculopathy; 3) SCS for FBSS; and 4) SCS for CRPS type 1. Based on the available data, we recommend not to use sympathetic blocks for PHN nor radiofrequency lesions for radiculopathy. No other conclusive recommendations can be made due to the poor quality of available data. Whenever possible, these interventions should either be part of randomized clinical trials or documented in pain registries. Priorities for future research include randomized clinical trials, long-term studies, and head-to-head comparisons among different interventional and noninterventional treatments.
This article investigates the benefits of adopting qualitative and quantitative sensory testing (QQST) in sensory assessment, with a focus on understanding neuropathic pain. The innovative QQST method combines participant qualitative experiences with quantitative psychophysical measurements, offering a more varied interpretation of sensory abnormalities and normal sensory function. This article also explores the steps for the optimization of the method by identifying qualitative signs of sensory abnormalities and standardizing data collection. By leveraging the inherent subjectivity in the test design and participant responses, the QQST method contributes to a more holistic exploration of both normal and abnormal sensory experiences. This article positions the QQST approach as a foundational element within the Sensory Evaluation Network, uniting international experts to harmonize qualitative and quantitative sensory evaluation methods.