Structures of the entire human opioid receptor family.

Opioids are effective analgesics, but their use is beset by serious side effects, including addiction and respiratory depression, which contribute to the ongoing opioid crisis. The human opioid system contains four opioid receptors (µOR, δOR, κOR, and NOPR) and a set of related endogenous opioid peptides (EOPs), which show distinct selectivity toward their respective opioid receptors (ORs). Despite being key to the development of safer analgesics, the mechanisms of molecular recognition and selectivity of EOPs to ORs remain unclear. Here, we systematically characterize the binding of EOPs to ORs and present five structures of EOP-OR-Gi complexes, including ß-endorphin- and endomorphin-bound µOR, deltorphin-bound δOR, dynorphin-bound κOR, and nociceptin-bound NOPR. These structures, supported by biochemical results, uncover the specific recognition and selectivity of opioid peptides and the conserved mechanism of opioid receptor activation. These results provide a structural framework to facilitate rational design of safer opioid drugs for pain relief.

Opioid analgesics for nociceptive cancer pain: A comprehensive review.

Pain is one of the most burdensome symptoms in people with cancer, and opioid analgesics are considered the mainstay of cancer pain management. For this review, the authors evaluated the efficacy and toxicities of opioid analgesics compared with placebo, other opioids, nonopioid analgesics, and nonpharmacologic treatments for background cancer pain (continuous and relatively constant pain present at rest), and breakthrough cancer pain (transient exacerbation of pain despite stable and adequately controlled background pain). They found a paucity of placebo-controlled trials for background cancer pain, although tapentadol or codeine may be more efficacious than placebo (moderate-certainty to low-certainty evidence). Nonsteroidal anti-inflammatory drugs including aspirin, piroxicam, diclofenac, ketorolac, and the antidepressant medicine imipramine, may be at least as efficacious as opioids for moderate-to-severe background cancer pain. For breakthrough cancer pain, oral transmucosal, buccal, sublingual, or intranasal fentanyl preparations were identified as more efficacious than placebo but were more commonly associated with toxicities, including constipation and nausea. Despite being recommended worldwide for the treatment of cancer pain, morphine was generally not superior to other opioids, nor did it have a more favorable toxicity profile. The interpretation of study results, however, was complicated by the heterogeneity in the study populations evaluated. Given the limited quality and quantity of research, there is a need to reappraise the clinical utility of opioids in people with cancer pain, particularly those who are not at the end of life, and to further explore the effects of opioids on immune system function and quality of life in these individuals.

Structural Basis for High-Affinity Trapping of the NaV1.7 Channel in Its Resting State by Tarantula Toxin.

Voltage-gated sodium channels initiate electrical signals and are frequently targeted by deadly gating-modifier neurotoxins, including tarantula toxins, which trap the voltage sensor in its resting state. The structural basis for tarantula-toxin action remains elusive because of the difficulty of capturing the functionally relevant form of the toxin-channel complex. Here, we engineered the model sodium channel NaVAb with voltage-shifting mutations and the toxin-binding site of human NaV1.7, an attractive pain target. This mutant chimera enabled us to determine the cryoelectron microscopy (cryo-EM) structure of the channel functionally arrested by tarantula toxin. Our structure reveals a high-affinity resting-state-specific toxin-channel interaction between a key lysine residue that serves as a "stinger" and penetrates a triad of carboxyl groups in the S3-S4 linker of the voltage sensor. By unveiling this high-affinity binding mode, our studies establish a high-resolution channel-docking and resting-state locking mechanism for huwentoxin-IV and provide guidance for developing future resting-state-targeted analgesic drugs.

Structure-based identification of a G protein-biased allosteric modulator of cannabinoid receptor CB1.

Cannabis sativa is known for its therapeutic benefit in various diseases including pain relief by targeting cannabinoid receptors. The primary component of cannabis, Δ9-tetrahydrocannabinol (THC), and other agonists engage the orthosteric site of CB1, activating both Gi and ß-arrestin signaling pathways. The activation of diverse pathways could result in on-target side effects and cannabis addiction, which may hinder therapeutic potential. A significant challenge in pharmacology is the design of a ligand that can modulate specific signaling of CB1. By leveraging insights from the structure-function selectivity relationship (SFSR), we have identified Gi signaling-biased agonist-allosteric modulators (ago-BAMs). Further, two cryoelectron microscopy (cryo-EM) structures reveal the binding mode of ago-BAM at the extrahelical allosteric site of CB1. Combining mutagenesis and pharmacological studies, we elucidated the detailed mechanism of ago-BAM-mediated biased signaling. Notably, ago-BAM CB-05 demonstrated analgesic efficacy with fewer side effects, minimal drug toxicity and no cannabis addiction in mouse pain models. In summary, our finding not only suggests that ago-BAMs of CB1 provide a potential nonopioid strategy for pain management but also sheds light on BAM identification for GPCRs.

Physicians prescribe fewer analgesics during night shifts than day shifts.

Adequate pain management is one of the biggest challenges of the modern healthcare system. Physician perception of patient subjective pain, which is crucial to pain management, is susceptible to a host of potential biases. Here we explore the timing of physicians' work as a previously unrecognized source of systematic bias in pain management. We hypothesized that during night shifts, sleep deprivation, fatigue, and stress would reduce physicians' empathy for others' pain, leading to underprescription of analgesics for patient pain relief. In study 1, 67 resident physicians, either following a night shift or not, performed empathy for pain assessment tasks and simulated patient scenarios in laboratory conditions. As predicted, following a night shift, physicians showed reduced empathy for pain. In study 2, we explored this phenomenon in medical decisions in the field. We analyzed three emergency department datasets from Israel and the United States that included discharge notes of patients arriving with pain complaints during 2013 to 2020 (n = 13,482). Across all datasets, physicians were less likely to prescribe an analgesic during night shifts (compared to daytime shifts) and prescribed fewer analgesics than generally recommended by the World Health Organization. This effect remained significant after adjusting for patient, physician, type of complaint, and emergency department characteristics. Underprescription for pain during night shifts was particularly prominent for opioids. We conclude that night shift work is an important and previously unrecognized source of bias in pain management, likely stemming from impaired perception of pain. We consider the implications for hospitals and other organizations employing night shifts.

Nonsteroidal anti-inflammatory drug "allergy" labeling is associated with increased postpartum opioid utilization.

BACKGROUND: Current guidelines recommend a stepwise approach to postpartum pain management, beginning with acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs), with opioids added only if needed. Report of a prior NSAID-induced adverse drug reaction (ADR) may preclude use of first-line analgesics, despite evidence that many patients with this allergy label may safely tolerate NSAIDs. OBJECTIVE: We assessed the association between reported NSAID ADRs and postpartum opioid utilization. METHODS: We performed a retrospective cohort study of birthing people who delivered within an integrated health system (January 1, 2017, to December 31, 2020). Study outcomes were postpartum inpatient opioid administrations and opioid prescriptions at discharge. Statistical analysis was performed on a propensity score-matched sample, which was generated with the goal of matching to the covariate distributions from individuals with NSAID ADRs. RESULTS: Of 38,927 eligible participants, there were 883 (2.3%) with an NSAID ADR. Among individuals with reported NSAID ADRs, 49.5% received inpatient opioids in the postpartum period, compared to 34.5% of those with no NSAID ADRs (difference = 15.0%, 95% confidence interval 11.4-18.6%). For patients who received postpartum inpatient opioids, those with NSAID ADRs received a higher total cumulative dose between delivery and hospital discharge (median 30.0 vs 22.5 morphine milligram equivalents [MME] for vaginal deliveries; median 104.4 vs 75.0 MME for cesarean deliveries). The overall proportion of patients receiving an opioid prescription at the time of hospital discharge was higher for patients with NSAID ADRs compared to patients with no NSAID ADRs (39.3% vs 27.2%; difference = 12.1%, 95% confidence interval 8.6-15.6%). CONCLUSION: Patients with reported NSAID ADRs had higher postpartum inpatient opioid utilization and more frequently received opioid prescriptions at hospital discharge compared to those without NSAID ADRs, regardless of mode of delivery.

"To prescribe or not to prescribe, that is the question": Perspectives on opioid prescribing for chronic, cancer-related pain from clinicians who treat pain in survivorship.

BACKGROUND: Opioid pain management in cancer survivorship is a complex and understudied topic. METHODS: The authors conducted in-depth, qualitative interviews to understand clinician approaches to opioid pain management in chronic cancer pain and to generate ideas for improvement. They used a rigorous, inductive, qualitative, descriptive approach to examine clinician (n = 20) perspectives about opioid pain management in survivorship, including oncologists (n = 5), palliative care clinicians (n = 8), primary care clinicians (n = 5), and pain management specialists (n = 2). RESULTS: The findings indicated that no consistent medical home exists for chronic pain management in cancer survivors and that there are fundamental differences in how each subspecialty approaches chronic pain management in survivorship (e.g., "Do we think of this as noncancer pain or cancer pain?… This is in this limbo zone-this gray zone-because it's cancer-related pain, right?"). Simultaneously, clinicians are influenced by their peers' perceptions of their opioid prescribing decisions, sparking intraprofessional tension when disagreement occurs. In these instances, clinicians described overthinking and doubting their clinical decision-making as well as a sense of judgment, pressure, and/or shame. Finally, clinicians acknowledged a fear of consequences for opioid prescribing decisions. Specifically, participants cited conflict with patients, sometimes escalating to aggression and threats of violence, as well as potential disciplinary actions and/or legal consequences. CONCLUSIONS: Participants suggested that opportunities to improve chronic cancer pain care include developing clear, systematic guidance for chronic cancer pain management, facilitating clinician communication and consultation, creating tailored survivorship care plans in partnership with patients, and developing accessible, evidence-based, complementary pain treatments.

Opioid metabolism and drug-drug interaction in cancer.

Concomitant use of multiple drugs in most patients with cancer may result in drug-drug interactions (DDIs), potentially causing serious adverse effects. These patients often experience unrelieved cancer-related pain (CRP) during and after cancer treatment, which can lead to a reduced quality of life. Opioids can be used as part of a multimodal pain management strategy when non-opioid analgesics are not providing adequate pain relief, not tolerated, or are contraindicated. However, due to their narrow therapeutic window, opioids are more susceptible to adverse events when a DDI occurs. Clinically relevant DDIs with opioids are usually pharmacokinetic, mainly occurring via metabolism by cytochrome P450 (CYP). This article aims to provide an overview of potential DDIs with opioids often used in the treatment of moderate-to-severe CRP and commonly used anticancer drugs such as chemotherapeutics, tyrosine kinase inhibitors (TKIs), or biologics. A DDI-checker tool was used to contextualize the tool-informed DDI assessment outcomes with clinical implications and practice. The findings were compared to observations from a literature search conducted in Embase and PubMed to identify clinical evidence for these potential DDIs. The limited results mainly included case studies and retrospective reviews. Some potential DDIs on the DDI-checker were aligned with literature findings, while others were contradictory. In conclusion, while DDI-checkers are useful tools in identifying potential DDIs, it is necessary to incorporate literature verification and comprehensive clinical assessment of the patient before implementing tool-informed decisions in clinical practice.

Buprenorphine Versus Diclofenac for Pain Relief in Acute Pancreatitis: A Double-Blinded Randomized Controlled Trial.

BACKGROUND: Although both nonsteroidal anti-inflammatory drugs (NSAIDs) and opioids are used for analgesia in acute pancreatitis (AP), the analgesic of choice is not known. We compared buprenorphine, an opioid, and diclofenac, an NSAID, for analgesia in AP. METHODS: In a double-blind randomized controlled trial, AP patients were randomized to receive intravenous diclofenac or intravenous buprenorphine. Fentanyl was used as rescue analgesia, delivered through a patient-controlled analgesia pump. Primary outcome was the difference in the dose of rescue fentanyl required. Secondary outcomes were the number of effective and ineffective demands of rescue fentanyl, pain-free interval, reduction in visual analogue scale (VAS) score, adverse events, and organ failure development. RESULTS: Twenty-four patients were randomized to diclofenac and 24 to buprenorphine. The 2 groups were matched at baseline. The total amount of rescue fentanyl required was significantly lower in the buprenorphine group:130 µg, interquartile range (IQR), 80-255 vs 520 µg, IQR, 380-1065 (P < .001). The number of total demands was 32 (IQR, 21-69) in the diclofenac arm vs 8 (IQR, 4-15) in the buprenorphine arm (P < .001). The buprenorphine group had more prolonged pain-free interval (20 vs 4 hours; P < .001), with greater reduction in the VAS score at 24, 48, and 72 hours compared with the diclofenac group. These findings were confirmed in the subgroup of moderately severe/severe pancreatitis. Adverse events profile was similar in the 2 groups. CONCLUSIONS: Compared with diclofenac, buprenorphine appears to be more effective and equally safe for pain management in AP patients, even in the subcohort of moderately severe or severe pancreatitis (Trial Registration number: CTRI/2020/07/026914).

NCP, a dual kappa and mu opioid receptor agonist, is a potent analgesic against inflammatory pain without reinforcing or aversive properties.

While agonists of mu (MOR) and kappa (KOR) opioid receptors have analgesic effects, they produce euphoria and dysphoria, respectively. Other side effects include respiratory depression and addiction for MOR agonists and sedation for KOR agonists. We reported that 17-cyclopropylmethyl-3,14ß-dihydroxy-4,5α-epoxy-6ß-{[4'-(2'-cyanopyridyl)]carboxamido}cmorphinan (NCP) displayed potent KOR full agonist and MOR partial agonist activities (58%) with 6.5x KOR-over-MOR selectivity in vitro Herein, we characterized pharmacological effects of NCP in rodents. In mice, NCP exerted analgesic effects against inflammatory pain in both the formalin test and the acetic acid writhing test, with A50 values of 47.6 and 14.4 microg/kg (s.c.), respectively. The analgesic effects in the acetic acid writhing test were mediated by the KOR. NCP at doses much higher than those effective in reducing inflammatory pain did not produce antinociception in the hot plate and tail flick tests, inhibit compound 48/80-induced scratching, cause conditioned place aversion (CPA) or preference, impair rotarod performance, inhibit locomotor activity, cause respiratory depression, or precipitate morphine withdrawal. However, NCP (10~100 microg/kg) inhibited gastrointestinal transit with a maximum of ~40% inhibition. In MOR knockout mice, NCP caused CPA, demonstrating that its lack of CPA is due to combined actions on the MOR and KOR. Following s.c. injection, NCP penetrated into the mouse brain. In rats trained to self-administer heroin, NCP (1~320 microg/kg/infusion) did not function as a reinforcer. Thus, NCP produces potent analgesic effects via KOR without side effects except constipation. Therefore, dual full KOR/partial MOR agonists with moderate KOR-over-MOR selectivity may be promising as non-addictive analgesics for inflammatory pain. Significance Statement Developing non-addictive analgesics is crucial for reducing opioid overdose deaths, minimizing drug misuse, and promoting safer pain management practices. Herein, pharmacology of a potential non-addictive analgesic, NCP, is reported. NCP has full KOR agonist / partial MOR agonist activities with a 6.5 x selectivity for KOR over MOR. Unlike MOR agonists, analgesic doses of NCP do not lead to self-administration or respiratory depression. Furthermore, NCP does not produce aversion, hypolocomotion, or motor incoordination, side effects typically associated with KOR activation.

Low-Efficacy Mu Opioid Agonists as Candidate Analgesics: Effects of Novel C-9 Substituted Phenylmorphans on Pain-Depressed Behavior in Mice.

Low efficacy mu opioid receptor (MOR) agonists may serve as novel candidate analgesics with improved safety relative to high-efficacy opioids. This study used a recently validated assay of pain-depressed behavior in mice to evaluate a novel series of MOR-selective C9-substituted phenylmorphan opioids with graded MOR efficacies. Intraperitoneal injection of dilute lactic acid (IP acid) served as a noxious stimulus to depress locomotor activity by mice in an activity chamber composed of two compartments connected by an obstructed door. Behavioral measures included (1) crosses between compartments (vertical activity over the obstruction) and (2) movement counts quantified as photobeam breaks summed across compartments (horizontal activity). Each drug was tested alone and as a pretreatment to IP acid. A charcoal-meal test and whole-body-plethysmography assessment of breathing in 5% CO2 were also used to assess gastrointestinal (GI) inhibition and respiratory depression, respectively. IP acid produced a concentration-dependent depression in crosses and movement that was optimally alleviated by intermediate- to low-efficacy phenylmorphans with sufficient efficacy to produce analgesia with minimal locomotor disruption. Follow-up studies with two low-efficacy phenylmorphans (JL-2-39 and DC-1-76.1) indicated that both drugs produced naltrexone-reversible antinociception with a rapid onset and a duration of ~1hr. Potency of both drugs increased when behavior was depressed by a lower IP-acid concentration, and neither drug alleviated behavioral depression by a non-pain stimulus (IP lithium chloride). Both drugs produced weaker GI inhibition and respiratory depression than fentanyl and attenuated fentanyl-induced GI inhibition and respiratory depression. Results support further consideration of selective, low-efficacy MOR agonists as candidate analgesics. Significance Statement This study used a novel set of mu opioid receptor (MOR)-selective opioids with graded MOR efficacies to examine the lower boundary of MOR efficacy sufficient to relieve pain-related behavioral depression in mice. Two novel low-efficacy opioids (JL-2-39, DC-1-76.1) produced effective antinociception with improved safety relative to higher- or lower-efficacy opioids, and results support further consideration of these and other low-efficacy opioids as candidate analgesics.

Gabapentin for Postoperative Pain Control and Opioid Reduction in Scrotal Surgery: A Randomized Controlled Clinical Trial.

PURPOSE: To assess the safety and efficacy of gabapentin in reducing postoperative pain among patients undergoing scrotal surgery for male infertility by conducting a randomized, double-blind, placebo-controlled trial. MATERIALS AND METHODS: In this randomized, double-blind, placebo-controlled trial, healthy men undergoing scrotal surgery with a single surgeon were randomized to receive either (1) gabapentin 600 mg given 2 hours preoperatively and 300 mg taken 3 times a day postoperatively for 3 days, or (2) inactive placebo. The primary outcome measure was difference in postoperative pain scores. Secondary outcomes included differences in opioid usage, patient satisfaction, and adverse events. RESULTS: Of 97 patients screened, 74 enrolled and underwent randomization. Of these, 4 men were lost to follow-up, and 70 were included in the final analysis (35 gabapentin, 35 placebo). Both differences in initial postoperative mean pain score (-1.14, 95% CI -2.21 to -0.08, P = .035) and final mean pain score differences (-1.27, 95% CI -2.23 to -0.32, P = .0097) indicated lower gabapentin pain compared to placebo. There were no statistically significant differences in opioid usage, patient satisfaction, or adverse events. CONCLUSIONS: These data suggest that perioperative gabapentin results in a statistically and clinically significant decrease in pain following scrotal surgery. While there was no evidence of an impact on opioid usage or patient satisfaction, given the low risk of adverse events, it may be considered as part of a multimodal pain management strategy.

Outcomes After a Statewide Policy to Improve Evidence-Based Treatment of Back Pain Among Medicaid Enrollees in Oregon.

BACKGROUND: A novel Oregon Medicaid policy guiding back pain management combined opioid restrictions with emphasis on non-opioid and non-pharmacologic therapies. OBJECTIVE: To examine the effect of the policy on prescribing, health outcomes, and health service utilization. DESIGN: Using Medicaid enrollment, medical and prescription claims, prescription drug monitoring program, and vital statistics files, we analyzed the policy's association with selected outcomes using interrupted time series models. SUBJECTS: Adult Medicaid patients with back pain enrolled between 2014 and 2018. INTERVENTION: The Oregon Medicaid back pain policy. MAIN MEASURES: Opioid and non-opioid medication prescribing, procedural care, substance use and mental health conditions, and outpatient and inpatient healthcare utilization. KEY RESULTS: The policy was associated with decreases in the percentage of Medicaid enrollees with back pain receiving any opioids (- 2.68 percentage points [95% CI - 3.14, - 2.23] level, - 1.01 pp [95% CI - 1.1, - 0.92] slope), days of short-acting opioid use (- 0.4 days [95% CI - 0.53, - 0.26] slope), receipt of more than 7 days of short-acting opioids (- 2.36 pp [95% CI - 2.76, - 1.95] level, - 0.91 pp [95% CI - 1, - 0.83] slope), chronic opioid use (- 1.27 pp [95% CI - 1.59, - 0.94] level, - 0.46 [95% CI - 0.53, - 0.39 slope), and spinal surgeries and procedures. Among secondary outcomes, we found no increase in opioid overdose and a small, statistically significant trend decrease in opioid use disorders. There were small increases in non-opioid substance use and mental health diagnoses and visits but no increase in self-harm. CONCLUSIONS: A state Medicaid policy emphasizing evidence-based back pain management was associated with decreases in opioid prescribing, spinal surgeries, and opioid use disorder trends, but also short-term increases in mental health encounters and an increase in non-opioid substance use disorder trends. Such policies may help reinforce evidence-based care, but must be designed with consideration of potential harms.

Impact of 30-day prescribed opioid dose trajectory on fatal overdose risk: A population-based, statewide cohort study.

BACKGROUND: Both increases and decreases in patients' prescribed daily opioid dose have been linked to increased overdose risk, but associations between 30-day dose trajectories and subsequent overdose risk have not been systematically examined. OBJECTIVE: To examine the associations between 30-day prescribed opioid dose trajectories and fatal opioid overdose risk during the subsequent 15 days. DESIGN: Statewide cohort study using linked prescription drug monitoring program and death certificate data. We constructed a multivariable Cox proportional hazards model that accounted for time-varying prescription-, prescriber-, and pharmacy-level factors. PARTICIPANTS: All patients prescribed an opioid analgesic in California from March to December, 2013 (5,326,392 patients). MAIN MEASURES: Dependent variable: fatal drug overdose involving opioids. Primary independent variable: a 16-level variable denoting all possible opioid dose trajectories using the following categories for current and 30-day previously prescribed daily dose: 0-29, 30-59, 60-89, or ≥90 milligram morphine equivalents (MME). KEY RESULTS: Relative to patients prescribed a stable daily dose of 0-29 MME, large (≥2 categories) dose increases and having a previous or current dose ≥60 MME per day were associated with significantly greater 15-day overdose risk. Patients whose dose decreased from ≥90 to 0-29 MME per day had significantly greater overdose risk compared to both patients prescribed a stable daily dose of ≥90 MME (aHR 3.56, 95%CI 2.24-5.67) and to patients prescribed a stable daily dose of 0-29 MME (aHR 7.87, 95%CI 5.49-11.28). Patients prescribed benzodiazepines also had significantly greater overdose risk; being prescribed Z-drugs, carisoprodol, or psychostimulants was not associated with overdose risk. CONCLUSIONS: Large (≥2 categories) 30-day dose increases and decreases were both associated with increased risk of fatal opioid overdose, particularly for patients taking ≥90 MME whose opioids were abruptly stopped. Results align with 2022 CDC guidelines that urge caution when reducing opioid doses for patients taking long-term opioid for chronic pain.

Physical job demands in pregnancy and associated musculoskeletal health and employment outcomes: a systematic review.

OBJECTIVE: A decline in musculoskeletal health during pregnancy is an underappreciated adverse outcome of pregnancy that can have immediate and long-term health consequences. High physical job demands are known risk factors for nontraumatic musculoskeletal disorders in the general working population. Evidence from meta-analyses suggest that occupational lifting and prolonged standing during pregnancy may increase risk of adverse pregnancy outcomes. This systematic review examined associations between occupational lifting or postural load in pregnancy and associated musculoskeletal disorders and related sequalae. DATA SOURCES: Five electronic databases (Medline, Embase, CINAHL, NIOSHTIC-2, and Ergonomic Abstracts) were searched from 1990 to July 2022 for studies in any language. A Web of Science snowball search was performed in December 2022. Reference lists were manually reviewed. STUDY ELIGIBILITY CRITERIA: Eligible studies reported associations between occupational lifting or postural load and musculoskeletal health or sequelae (eg, employment outcomes) among pregnant and postpartum workers. METHODS: Data were extracted using a customized form to document study and sample characteristics; and details of exposures, outcomes, covariates, and analyses. Investigators independently assessed study quality for 7 risk-of-bias domains and overall utility, with discrepant ratings resolved through discussion. A narrative synthesis was conducted due to heterogeneity. RESULTS: Sixteen studies (11 cohort studies, 2 nested case-control studies, and 3 cross-sectional studies) from 8 countries were included (N=142,320 pregnant and N=1744 postpartum workers). Limited but consistent evidence with variable quality ratings, ranging from critical concern to high, suggests that pregnant workers exposed to heavy lifting (usually defined as ≥22 lbs or ≥10 kg) may be at increased risk of functionally limiting pelvic girdle pain and antenatal leave. Moreover, reports of dose-response relationships suggest graded risk levels according to lifting frequency, ranging from 21% to 45% for pelvic girdle pain and 58% to 202% for antenatal leave. Limited but consistent evidence also suggests that postural load increases the risk of employment cessation. CONCLUSION: Limited but consistent evidence suggests that pregnant workers exposed to heavy lifting and postural load are at increased risk of pelvic girdle pain and employment cessation. Job accommodations to reduce exposure levels may promote safe sustainable employment for pregnant workers.

Factors associated with unplanned clinical encounters for ureteral stent-related symptoms.

BACKGROUND, INTRODUCTION AND AIM: Ureteral stent-related symptoms (USRS) often result in unplanned phone calls and ER visits. We hypothesize that patient factors can be identified to predict these unplanned encounters. METHODS AND MATERIALS: Retrospective analysis of indwelling ureteral stent placements from 2014 to 2019 at a single institution by CPT code was performed. Patient demographics, discharge medications, and clinical factors were evaluated using multiple logistic regression with respect to postoperative telephone and emergency room (ER) encounters for USRS. RESULTS: Of 374 patients, 75 (20.1%) had one or more encounters for USRS: 48 (12.8%) called the clinic and 39 (10.4%) returned to the ER. Chronic opioid use was predictive of calls to clinic and ER visits (OR 3.21 [CI 1.42-6.97], p < 0.01 and OR 3.64 [CI 1.45-8.98], p < 0.01). Survival analysis stratified by history of chronic opioid use and discharge opioid prescriptions demonstrated that opioid naïve patients receiving opioids at discharge had unplanned encounters sooner and more often [Calls p = 0.025, ER p = 0.041]), whereas patients with chronic opioid use returned to the ER sooner and more frequently when prescribed additional opioids (Calls p = 0.4, ER p = 0.002). CONCLUSION: Patients with a history of chronic opioid use may experience more intense USRS or have a lower threshold to seek medical care than opioid naïve patients and tend to bypass calling the clinic for the ER. Given that none of the studied medications reduced unplanned patient contact for USRS, urologists should consider upfront definitive management of urinary obstruction when appropriate.

A retrospective analysis of perioperative medications for opioid-use disorder and tapering additional postsurgical opioids via a transitional pain service.

AIMS: To investigate perioperative opioid requirements in patients on methadone or buprenorphine as medication for opioid-use disorder (MOUD) who attended a transitional pain clinic (Personalized Pain Program, PPP). METHODS: This retrospective cohort study assessed adults on MOUD with surgery and attendance at the Johns Hopkins PPP between 2017 and 2022. Daily non-MOUD opioid use over 6 time-points was evaluated with regression models controlling for days since surgery. The time to complete non-MOUD opioid taper was analysed by accelerated failure time and Kaplan-Meier models. RESULTS: Fifty patients (28 on methadone, 22 on buprenorphine) were included with a median age of 44.3 years, 54% male, 62% Caucasian and 54% unemployed. MOUD inpatient administration occurred in 92.8% of patients on preoperative methadone but only in 36.3% of patients on preoperative buprenorphine. Non-MOUD opioid use decreased over time postoperatively (ß = -0.54, P < .001) with a median decrease of 90 mg morphine equivalents (MME) between the first and last PPP visit, resulting in 46% tapered off by PPP completion. Older age and duration in PPP were associated with lower MME, while mental health conditions, longer hospital stays and higher discharge opioid prescriptions were associated with higher MME. The average time to non-MOUD opioid taper was 1.79× longer in patients on buprenorphine (P = .026), 2.75× in males (P = .023), 4.66× with mental health conditions (P < .001), 2.37× with chronic pain (P = .031) and 3.51× if on preoperative non-MOUD opioids; however, higher initial MOUD level decreased time to taper (P = .001). CONCLUSIONS: Postoperative opioid tapering utilizing a transitional pain service is possible in patients on MOUD.

Prevalence and characteristics of pain in patients with lower-extremity ulcers-A cross-sectional study.

The study aimed to investigate the prevalence and characteristics of pain in different ulcer types and to identify factors associated with pain experience in patients with lower-extremity ulcers. A cross-sectional single-centre study was performed, including 130 newly referred outpatients with lower-extremity ulcers. Pain intensity was measured with a visual analog scale (VAS) and pain characteristics with the short form mcgill pain questionnaire-2 (SF-MPQ-2). The mean pain intensity was 29.5 (SD 31.8) at rest and 35.5 (SD 34.1) during movement (0-100 VAS). 61.5% of the patients experienced pain (VAS > 0) at rest and 70.8% during movement. Moderate to severe pain at rest was seen in 39.2% and in 43.8% of patients during movement. The mean total score on SF-MPQ-2 (range 0-220) was 35.9 (SD 32.6). Most of the patients described pain as intermittent (mean 11.8 SD 13.9). Analgesics were prescribed for 78% of the patients. Ulcer type (i.e., arterial, immunological, pressure and venous) and age were associated with pain severity, and women had a significantly lower well-being score than men. Prevalence of pain in patients with lower-extremity ulcers was high across different ulcer aetiologies. Pain intensity and quality must be assessed to obtain adequate pain management.

Maternal opioid use disorder and infant mortality in Wisconsin, United States, 2010-2018.

OBJECTIVE: The difference in infant health outcomes by maternal opioid use disorder (OUD) status is understudied. We measured the association between maternal OUD during pregnancy and infant mortality and investigated whether this association differs by infant neonatal opioid withdrawal syndrome (NOWS) or maternal receipt of medication for OUD (MOUD) during pregnancy. METHODS: We sampled 204,543 Medicaid-paid births from Wisconsin, United States (2010-2018). The primary exposure was any maternal OUD during pregnancy. We also stratified this exposure on NOWS diagnosis (no OUD; OUD without NOWS; OUD with NOWS) and on maternal MOUD receipt (no OUD; OUD without MOUD; OUD with <90 consecutive days of MOUD; OUD with 90+ consecutive days of MOUD). Our outcome was infant mortality (death at age <365 days). Demographic-adjusted logistic regressions measured associations with odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Maternal OUD was associated with increased odds of infant mortality (OR 1.43; 95% CI 1.02-2.02). After excluding infants who died <5 days post-birth (i.e., before the clinical presentation of NOWS), regression estimates of infant mortality did not significantly differ by NOWS diagnosis. Likewise, regression estimates did not significantly differ by maternal MOUD receipt in the full sample. CONCLUSIONS: Maternal OUD is associated with an elevated risk of infant mortality without evidence of modification by NOWS nor by maternal MOUD treatment. Future research should investigate potential mechanisms linking maternal OUD, NOWS, MOUD treatment, and infant mortality to better inform clinical intervention.

Cohort profile: The Copenhagen Analgesic Study-The COPANA cohort.

BACKGROUND: Development of the gonads during fetal life is complex and vital for adult reproductive health. Cell and animal studies have shown an alarming effect of mild analgesics on germ cells in both males and females. More than 50% of pregnant women use mild analgesics during pregnancy, which potentially could compromise the reproductive health of the next generation. OBJECTIVES: We present a research protocol designed to evaluate the effect of prenatal exposure to mild analgesics and endocrine-disrupting chemicals on gonadal function in the offspring. POPULATION: Healthy, singleton pregnant women and their partners. DESIGN: The COPANA cohort is a prospective, observational pregnancy and birth cohort. METHODS: Participants were enrolled during the first trimester of pregnancy. Information on the use of mild analgesics was collected retrospectively 3 months prior to pregnancy and prospectively every 2 weeks throughout the study. We collected extensive data on lifestyle and reproductive health. Biospecimens were collected in the first trimester (maternal and paternal urine- and blood samples), in the third trimester in conjunction with a study-specific ultrasound scan (maternal urine sample), and approximately 3 months post-partum during the infant minipuberty period (maternal and infant urine- and blood samples). A comprehensive evaluation of reproductive function in the infants during the minipuberty phase was performed, including an ultrasound scan of the testis or ovaries and uterus. PRELIMINARY RESULTS: In total, 685 pregnant women and their partners were included between March 2020 and January 2022. A total of 589 infants (287 males) and their parents completed the follow-up during the minipuberty phase (December 2020-November 2022). CONCLUSIONS: The Copenhagen Analgesic Study holds the potential to provide novel and comprehensive insights into the impact of early and late prenatal exposure to mild analgesics and other endocrine-disrupting chemicals on future reproductive function in the offspring.