A Longitudinal Study of the Association of Opioid Use with Change in Pain Interference and Functional Limitations in a Nationally Representative Cohort of Adults with Osteoarthritis in the United States

Pain and Perception: Exploring Psychedelics as Novel Therapeutic Agents in Chronic Pain Management

PURPOSE OF REVIEW

Chronic pain affects approximately 1.5 billion people worldwide, representing the leading cause of disability and a significant financial burden on healthcare systems. Conventional treatments, such as opioids and non-steroidal anti-inflammatory drugs, are frequently linked to adverse effects, including dependency and gastrointestinal issues, and often offer limited long-term relief. This review explores the potential of psychedelics, including psilocybin, LSD, and ketamine, as alternative therapeutic agents in chronic pain management.

RECENT FINDINGS

These substances modulate pain perception through actions on serotonergic and glutamatergic systems and may promote neuroplasticity, offering novel pathways for pain relief. Specifically, the review details the pharmacologic actions of psychedelics, their effects on chronic pain syndromes such as cancer pain, migraines, and neuropathic pain, and their clinical implications. The safety profiles, patient responses, and analgesic properties of these compounds are examined, highlighting the need for further research to validate their efficacy and optimize their therapeutic use in pain management.

Engagement in Integrative and Nonpharmacologic Pain Management Modalities Among Adults with Chronic Pain: Analysis of the 2019 National Health Interview Survey

Objective

To examine variables associated with engagement in (1) integrative health and medicine (IHM) and (2) nonpharmacologic modalities rather than opioids among United States adults with chronic pain.

Methods

Using the 2019 National Health Interview Survey, we examined sociodemographic, pain, and mental health predictors of (1) the sum of IHM modalities (ie, chiropractic care, yoga/Tai Chi, massage, or meditation/guided imagery) used to manage pain and (2) exclusive engagement in nonpharmacologic pain management modalities (ie, IHM, a chronic pain self-management program, support groups, or physical, rehabilitative, occupational, or talk therapy) or opioids in the past 3 months.

Results

Metropolitan residency, higher family income, higher education levels, increased number of pain locations, and increased frequency of pain limiting life/work activities were associated with increased odds of IHM engagement. Older age, male sex, non-Hispanic Black/African American race/ethnicity, and daily opioid use were associated with decreased odds of IHM engagement. Older age, male sex, and increased depressive symptoms were associated with decreases in the count of IHM modalities used to manage pain. Metropolitan residency, higher family income, and higher education levels were associated with increased odds of exclusive nonpharmacologic modality engagement. Older age and increasing frequency of pain limiting life/work activities were associated with decreased odds of exclusive nonpharmacologic modality engagement.

Conclusions

We identified several contrasts between factors prevalent among individuals with chronic pain and factors associated with engagement in nonpharmacologic and IHM modalities. These results support efforts to address barriers to accessing these modalities among subpopulations of adults with chronic pain (eg, older adults, individuals identifying as Black/African American, rural residents, and those with lower levels of education and income).

Use of Psychedelics for Pain: A Scoping Review

Chronic pain is a public health concern that affects approximately 1.5 billion people globally. Conventional therapeutic agents including opioid and non-opioid analgesics have been associated with adverse side effects, issues with addiction, and ineffective analgesia. Novel agents repurposed to treat pain via different mechanisms are needed to fill the therapeutic gap in chronic pain management. Psychedelics such as lysergic acid diethylamide and psilocybin (the active ingredient in psychedelic mushrooms) are thought to alter pain perception through direct serotonin receptor agonism, anti-inflammatory effects, and synaptic remodeling. This scoping review was conducted to identify human studies in which psychedelic agents were used for the treatment of pain. Twenty-one articles that assessed the effects of psychedelics in treating various pain states were included. The present scarcity of clinical trials and small sample sizes limit their application for clinical use. Overall, psychedelics appear to show promise for analgesia in patients with certain headache disorders and cancer pain diagnoses. Future studies must aim to examine the combined effects of psychotherapy and psychedelics on chronic pain.

A Review of Potential National Chronic Pain Surveillance Systems in the United States

Pain has been established as a major public health problem in the United States (U.S.) with 50 million adults experiencing chronic pain and 20 million afflicted with high-impact chronic pain (ie, chronic pain that interferes with life or work activities). High financial and social costs are associated with chronic pain. Over the past 2 decades, pain management has been complicated by the marked increase in opioids prescribed to treat chronic noncancer pain and by the concurrent opioid crisis. Monitoring the prevalence of chronic pain and pain management is especially important because pain management is changing in uncertain ways. We review potential U.S. chronic pain surveillance systems, present potential difficulties of chronic pain surveillance, and explore how to address chronic pain surveillance in the current opioid era. We consider case definitions, severity, anatomic site, and varieties of chronic pain management strategies in reviewing and evaluating national surveys for chronic pain surveillance. Based on the criteria evaluated, the National Health Interview Survey offers the best single source for pain surveillance as the pain-related questions administered are brief, valid, and cover a broad scope of pain-related phenomena. PERSPECTIVE: This review article describes data sources that can be leveraged to conduct national chronic pain surveillance in the United States, explores case defining or pain-related questions administered, and evaluates them against 8 surveillance attributes.

The effect of long-term opioid use on back-specific disability and health-related quality of life in patients with chronic low back pain

CONTEXT

Opioids are commonly utilized for the treatment of chronic pain. However, research regarding the long-term (≥12 months) outcomes of opioid therapy remains sparse.

OBJECTIVES

This study aims to evaluate the effects of long-term opioid therapy on measures of back-specific disability and health-related quality of life in patients with chronic low back pain.

METHODS

In this retrospective cohort study, patients with chronic low back pain who reported consistent opioid use or abstinence for at least 12 months while enrolled in the Pain Registry for Epidemiological, Clinical, and Interventional Studies and Innovation Pain Research Registry were classified as long-term opioid users or nonusers, respectively. For comparison, intermediate-term and short-term opioid users and nonusers were also identified. Multiple linear regression analysis was performed to compare back-specific disability (Roland-Morris Disability Questionnaire [RMDQ]) and health-related quality of life (29-item Patient-Reported Outcomes Measurement Information System [PROMIS]) between opioid users and nonusers while controlling for pain intensity, depression, age, body mass index (BMI), and eight common comorbid conditions (herniated disc, sciatica, osteoporosis, osteoarthritis, heart disease, hypertension, diabetes, and asthma). Statistically significant findings were assessed for clinical relevance.

RESULTS

There were 96 long-term opioid users and 204 long-term opioid nonusers. After controlling for potential confounders, long-term opioid use was a predictor of worse back-specific disability (adjusted mean difference=2.85, p<0.001), physical function (adjusted mean difference=-2.90, p=0.001), fatigue (adjusted mean difference=4.32, p=0.001), participation in social roles (adjusted mean difference=-4.10, p<0.001), and pain interference (adjusted mean difference=3.88, p<0.001) outcomes. Intermediate-term opioid use was a predictor of worse back-specific disability (adjusted mean difference=2.41, p<0.001), physical function (adjusted mean difference=-2.26, p=0.003), fatigue (adjusted mean difference=3.70, p=0.002), and sleep disturbance outcomes (adjusted mean difference=3.03, p=0.004), whereas short-term opioid use was a predictor of worse back-specific disability (adjusted mean difference=2.42, p<0.001) and physical function outcomes (adjusted mean difference=-1.90, p<0.001).

CONCLUSIONS

The findings of this study are largely consistent with existing literature regarding the outcomes of long-term opioid therapy. Taken in conjunction with the well-established risks of opioid medications, these findings draw into question the utility of long-term opioid therapy for chronic low back pain.

Complex Persistent Opioid Dependence-an Opioid-induced Chronic Pain Syndrome

OPINION STATEMENT

Long-term opioid therapy (LTOT) for chronic cancer and non-cancer pain is commonly ineffective in providing its stated goal of improving function through good control of pain. Opioid tapering (slow dose reduction and/or discontinuation), the logical solution, also appears to be ineffective among many patients on LTOT as it often leads to even worse pain control and function, leaving the patients and providers managing LTOT in a clinical conundrum with little treatment choices. Complex persistent opioid dependence (CPOD) was recently offered as a heuristic to explain this clinical conundrum exemplified by the ineffectiveness of both LTOT and opioid tapering. This manuscript provides a detailed description of the neurobehavioral underpinnings of CPOD, explaining how long-term opioid use can lead to more pain even while experiencing relief with each opioid dose. CPOD is characterized by the allostatic opponent mechanisms of neuroadaptations related to the progression of opioid dependence and tolerance involving nociceptive/anti-nociceptive brain systems causing opioid-induced hyperalgesia and reward/anti-reward systems causing hyperkatefia or suffering that induces pain experience through the cognitive/emotional component of pain mechanisms. "Opioid Induced Chronic Pain syndrome" (OICP) is offered as an alternate clinical diagnostic term instead of CPOD that has several limitations as a diagnosis term including poor patient acceptance due to stigma towards addiction and clinical confounding with opioid use disorder, a related but separate clinical entity. OICP with LTOT is conceptualized as a recoverable iatrogenic problem that can be managed by pain providers. Broad guidance on management of OICP is also provided.

A Retrospective Claims-Based Study Evaluating Clinical and Economic Burden Among Patients With Moderate to Severe Osteoarthritis Pain in the United States

Background: There has been limited evaluation of medication adherence, healthcare resource utilization (HCRU), and healthcare costs over time in patients with osteoarthritis (OA), and stratification by pain severity level has not been reported. Assessing such longitudinal changes may be useful to patients and healthcare providers for tracking disease progression, informing treatment options, and employing strategies to optimize patient outcomes. Objectives: To characterize treatment patterns, HCRU, and costs over time in patients with moderate to severe (MTS) OA pain in the United States. Methods: We conducted a retrospective claims analysis, using IBM® MarketScan® databases, from 2013-2018. Eligible patients were aged ≥45 years with ≥12 months pre-index (baseline) and ≥24 months (follow-up) of continuous enrollment; index date was defined as a physician diagnosis of hip or knee OA. An algorithm was employed to identify MTS OA pain patients, who were propensity score matched with patients having non-MTS OA pain. Data were summarized using descriptive statistics and univariate analyses. Results: After propensity score matching, the overall OA pain cohorts consisted of 186 374 patients each: 61% were female, mean age was 63 years, and two-thirds (65.6%) were of working age (45-65 years). Sleep-related conditions, anxiety, and depression were significantly higher in the MTS OA pain cohort vs non-MTS (P<0.001). At baseline and 12- and 24-month follow-ups, receipt of prescription pain medications, HCRU, and direct medical costs were significantly higher in the MTS OA pain cohort (all P<0.01). Medication adherence was significantly higher in the MTS OA pain cohort for all medication classes except analgesics/antipyretics, which were significantly lower vs the non-MTS OA pain cohort (all P<0.0001). Conclusions: The burden of MTS OA pain is substantial, with patterns that show increasing medication use, HCRU, and costs vs non-MTS OA pain patients over time. Understanding the heterogeneity within the OA population may allow us to further appreciate the true burden of illness for patients in pain.

Impact of tanezumab on health status, non-work activities and work productivity in adults with moderate-to-severe osteoarthritis

BACKGROUND

To evaluate the impact of tanezumab on health status, non-work activities, and work productivity in a pooled analysis of two large phase 3 osteoarthritis (OA) studies.

METHODS

Subcutaneous tanezumab (2.5 mg and 5 mg) was tested in double-blind, placebo-controlled, 16-week (NCT02697773) and 24-week (NCT02709486) clinical trials in patients with moderate-to-severe OA of the hip or knee. At baseline and week 16, all patients completed EQ-5D-5L and the Work Productivity and Activity Impairment-OA (WPAI-OA) activity impairment item. Those currently employed also completed WPAI-OA work time missed, impairment while working, and overall work impairment items. Between-group differences in least squares (LS) mean changes from baseline at week 16 were tested using analysis of covariance.

RESULTS

Of 1545 pooled patients, 576 were employed at baseline. Improvements in EQ-5D-5L index value at week 16 were significantly greater for the tanezumab 2.5-mg group (difference in LS means [95% confidence interval (CI), 0.03 [0.01, 0.05]; p = 0.0083) versus placebo. Percent improvements (95% CI) in activity impairment (- 5.92 [- 8.87, - 2.98]; p < 0.0001), impairment while working (- 7.34 [- 13.01, - 1.68]; p = 0.0112), and overall work impairment (- 7.44 [- 13.22, - 1.67]; p = 0.0116) at week 16 were significantly greater for the tanezumab 2.5-mg group versus placebo. Results for the tanezumab 5-mg group were generally comparable to the tanezumab 2.5-mg group, although, compared with placebo, percent improvement (95% CI) in work time missed was significantly greater for the tanezumab 5-mg group (- 3.40 [- 6.47, - 0.34]; p = 0.0294), but not the tanezumab 2.5-mg group (- 0.66 [- 3.63, 2.32]; p = 0.6637).

CONCLUSIONS

These pooled analyses showed that health status, non-work activities, and work productivity were significantly improved following tanezumab administration, compared with placebo.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02697773, NCT02709486.

TGF-β1 in plasma and cerebrospinal fluid can be used as a biological indicator of chronic pain in patients with osteoarthritis

Introduction

Previous studies have demonstrated that cytokines, transforming growth factor (TGF-β1), and brain-derived neurotrophic factor (BDNF) can impact the intensity of pain in rodents. However, the roles of cytokines, TGF-β1 and BDNF in humans with chronic pain in osteoarthritis remains unclear, and no comparison between plasma and central cerebral spinal fluid (CSF) has been conducted.

Methods

Patients with osteoarthritis who were scheduled to receive spinal anesthesia were enrolled. The intensity of pain was evaluated with a visual analogue scale (VAS). In addition, patients with genitourinary system (GU) diseases and without obvious pain (VAS 0–1) were included as a comparison (control) group. The levels of TGF-β1, BDNF, tumor necrosis factor-α (TNF-α), and interleukin (IL)-8 within the CSF and plasma were collected and evaluated before surgery.

Results

The plasma and CSF TGF-β1 levels were significantly lower in the osteoarthritis patients with pain (VAS ≥ 3) than in the GU control patients. Downregulation of plasma BDNF was also found in osteoarthritis patients with pain. The Spearman correlation analysis showed that the VAS pain scores were significantly negatively correlated with the levels of TGF-β1 in the CSF of patients with osteoarthritis. However, there was no significant correlations between the pain scores and the levels of BDNF, TNF-α, and IL-8 in either the CSF or plasma.

Conclusions

TGF-β1 but not BDNF, TNF-α, or IL-8 may be an important biological indicator in the CSF of osteoarthritis patients with chronic pain.

A Retrospective Cohort Analysis of the Impact of Osteoarthritis on Disability Leave, Workers' Compensation Claims, and Healthcare Payments

OBJECTIVES

Examine short-term disability (STD) and workers' compensation (WC) associated leave and wage replacements, and overall direct healthcare payments, among employees with osteoarthritis (OA) versus other chronically painful conditions; quantifying the impact of opioid use.

METHODS

Analysis of employees with more than or equal to two STD or WC claims for OA or pre-specified chronically painful conditions (control) in the IBM MarketScan Research Databases (2014 to 2017).

RESULTS

The OA cohort (n = 144,355) had an estimated +1.2 STD days, +$152 STD payments, and +$1410 healthcare payments relative to the control cohort (n = 392,639; P < 0.001). WC days/payments were similar. Differences were partially driven by an association between opioid use, increased STD days/payments, and healthcare payments observed in pooled cohorts (P < 0.001).

CONCLUSIONS

OA is associated with high STD days/payments and healthcare payments. Opioid use significantly contributes to these and this should be considered when choosing treatment.

Patient self-reported functioning by pain severity and usual analgesic treatment among older adults with osteoarthritis: analysis of the 2017 Spanish National Health Survey

PURPOSE

Osteoarthritis (OA) pain is among the leading causes of disability worldwide in older people. Since its prevalence is growing in aging, a significant burden for society is expected. This work ascertained whether level of disability in self-reported functioning differs by pain severity and usual analgesic treatment among older OA patients in Spain.

METHODS

The Spanish-National-Health-Survey, a large, nationally representative, cross-sectional general health survey including 23,089 persons, was analyzed. Patients aged 65 + years with a self-reported physician OA diagnosis were classified according to severity of pain (no/mild, moderate or severe pain) and treated or untreated with analgesia. Assessment of function included basic and instrumental activities-of-daily-living (BADL, IADL), mental, social, and cognitive functions, scored on a 0% (no limitation) to 100% (complete limitation) standardized metric. Caregiver need for BADL and IADL was also recorded.

RESULTS

A total of 3526 patients were analyzed (women 73.3%; age 77.4 [SD: 7.5]). Adjusted functioning scores showed significant association with pain severity, and for BADL, IADL and social function. Patients with severe pain and treated with analgesia had higher limitation scores, ranging on average between 31.5% on BADL, 34.1% on IADL, 45.0% on mental, 42.2% on social, and 23.4% in cognitive domain. The proportions of patients needing a caregiver for BADL (43.4%) and IADL (56.2%) were also the highest in patients with severe pain and treated with analgesia.

CONCLUSIONS

Regardless of usual utilization of analgesics, the severity of pain seemed to be the major determinant of functional impairment, and caregiving need, in all domains of functioning in older OA patients in Spain. Existing treatment strategies are analgesics based and do not meet patient needs for adequate pain management.

5-O-methylcneorumchromone K Exerts Antinociceptive Effects in Mice via Interaction with GABAA Receptors

The proper pharmacological control of pain is a continuous challenge for patients and health care providers. Even the most widely used medications for pain treatment are still ineffective or unsafe for some patients, especially for those who suffer from chronic pain. Substances containing the chromone scaffold have shown a variety of biological activities, including analgesic effects. This work presents for the first time the centrally mediated antinociceptive activity of 5-O-methylcneorumchromone K (5-CK). Cold plate and tail flick tests in mice showed that the 5-CK-induced antinociception was dose-dependent, longer-lasting, and more efficacious than that induced by morphine. The 5-CK-induced antinociception was not reversed by the opioid antagonist naloxone. Topological descriptors (fingerprints) were employed to narrow the antagonist selection to further investigate 5-CK's mechanism of action. Next, based on the results of fingerprints analysis, functional antagonist assays were conducted on nociceptive tests. The effect of 5-CK was completely reversed in both cold plate and tail-flick tests by GABA_A receptor antagonist bicuculline, but not by atropine or glibenclamide. Molecular docking studies suggest that 5-CK binds to the orthosteric binding site, with a similar binding profile to that observed for bicuculline and GABA. These results evidence that 5-CK has a centrally mediated antinociceptive effect, probably involving the activation of GABAergic pathways.