Preliminary Evidence for the Sequentially Mediated Effect of Racism-Related Stress on Pain Sensitivity Through Sleep Disturbance and Corticolimbic Opioid Receptor Function

Assessing pain in persons with opioid use disorder: Approaches, techniques and special considerations

Pain and opioid use disorder (OUD) are inextricably linked, as the former can be a risk factor for the development of the latter, and over a third of persons with OUD suffer concomitant chronic pain. Assessing pain among people with OUD is challenging, because ongoing opioid use brings changes in pain responses and most pain assessment tools have not been validated for this population. In this narrative review, we discuss the fundamentals of pain assessment for populations with OUD. First, we describe the biological, psychological and social aspects of the pain experience among people with OUD, as well as how opioid-related phenomena may contribute to the pain experience in this population. We then review methods to assess pain, including (1) traditional self-reported methods, such visual analogue scales and structured questionnaires; (2) behavioural observations and physiological indicators; (3) and laboratory-based approaches, such as quantitative sensory testing. These methods are considered from a perspective that encompasses both pain and OUD. Finally, we discuss strategies for improving pain assessment in persons with OUD and implications for future research, including educational strategies for multidisciplinary teams. We highlight the substantial gaps that persist in this literature, particularly regarding the applicability of current pain assessment methods to persons with OUD, as well as the generalizability of the existing results from adjacent populations on chronic opioid therapy but without OUD. As research linking pain and OUD evolves, considering the needs of diverse populations with complex psychosocial backgrounds, clinicians will be better equipped to reduce these gaps.

Endogenous opiates and behavior: 2023

This paper is the forty-sixth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2023 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug and alcohol abuse (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Disentangling the effects of racism-related stress on opioid use disorder and chronic pain outcomes

In recent years, Black people in the U.S. have had one of the highest increases in opioid overdose mortality rates, despite being less likely to be prescribed opioids for pain. This population is also less likely to receive medications for opioid use disorder (MOUD). Chronic pain is a central factor in understanding this crisis, as minoritized people are more likely to live with undertreated pain, a major risk factor for developing opioid use disorder (OUD). Current practices fail to effectively treat pain among persons with OUD, a missed opportunity that is worse in minoritized populations and further producing disparities. In this perspective, we discuss how racism-related stress and disparities in addiction treatments may impact the pain experience, diagnosis, treatment, contribute to developing OUD, and perpetuate stigma. This high-level perspective invites clinicians and researchers to reflect on the biopsychosocial burden imposed upon historically minoritized people with pain and OUD. To address such complex issues, multidisciplinary efforts and methodological improvements are required, imbued by antiracist values. Collaboration across disciplines is necessary toward the common goal of improving pain management and mitigating opioid mortality among minoritized populations. As antiracist perspectives inform research practices and cultural humility principles guide care, we will be better equipped to close current gaps in knowledge and address widening healthcare disparities.

Secondary analysis: heat and self-report pain sensitivity associate with biological sex and racialized sociocultural group but may not be mediated by anxiety or pain catastrophizing

Introduction

Previous studies have demonstrated associations between sex and racialized group on pain sensitivity and tolerance. We analyzed the association of sex and racialized group on heat pain sensitivity, sensibility to painful suprathreshold mechanical pain (STMP), and pain sensitivity questionnaire (PSQ). We hypothesized that anxiety and pain catastrophizing reported by racialized minority groups and women would mediate enhanced pain sensitivity. Our secondary aim was to evaluate validity of the PSQ in a diverse population.

Methods

Using quantitative sensory testing for painful heat, STMP (forces: 64, 128, 256, and 512 mN), and PSQ, we evaluated pain sensitivity in 134 healthy participants [34 (18 women) Asian, 25 (13 women) Black, and 75 (41 women) White]. We used general linear and linear mixed models to analyze outcomes. We assessed mediation of state and trait anxiety and pain catastrophizing on pain sensitivity.

Results

Racialized minority status was associated with greater heat pain sensitivity (F = 7.63; P = 0.00074) and PSQ scores (F = 15.45; P = 9.84 × 10-7) but not associated with STMP (F = 1.50; P = 0.23). Female sex was associated with greater heat pain sensitivity (F = 4.9; P = 0.029) and lower PSQ (F = 9.50; P = 0.0025) but not associated with STMP (F = 0.0018; P = 0.97). Neither anxiety nor pain catastrophizing mediated associations between sex or racialized group with heat pain threshold or PSQ. Differential experience of individual items (F = 19.87; P = 3.28 × 10-8) limited PSQ face validity in racialized minorities.

Conclusion

Consistent with previous research, sensitivity to painful heat was associated with racialized minority status and female sex. By contrast, there was no significant effect of racialized minority status or female sex on STMP. Some PSQ items are inapplicable to participants from racialized minority groups.