Gabapentin for chronic neuropathic pain in adults

Prescribing Patterns and Off-Label Use of Gabapentinoid Agents at Dhulikhel Hospital, Nepal: A Cross-Sectional Study

Purpose

Gabapentinoids are mainly prescribed for neuropathic pain and certain seizure disorders, but their off-label use has increased significantly. This rise raises concerns about the insufficient evidence supporting some applications, as well as potential risks of misuse, dependence, and adverse effects. The study aims to examine the prescribing patterns and off-label use of gabapentinoids at Dhulikhel Hospital (DH), Nepal, focusing on understanding the extent of off-label practices and patient knowledge regarding their medications.

Patients and Methods

A cross-sectional survey of 385 adult patients prescribed gabapentinoids was conducted at the outpatient pharmacy of DH. Data were collected via patient interviews and prescriptions. Off-label use was assessed according to the licensed indications of the US Food and Drug Administration (FDA) and the UK British National Formulary (BNF). Statistical analysis was performed using Statistical Package for the Social Sciences version 26.

Results

Among patients prescribed gabapentinoids, 73.0% received gabapentin while 27.0% were prescribed pregabalin. Most patients were middle-aged females with comorbid conditions, primarily orthopedic outpatients. Off-label use was prevalent, with 96.1% of prescriptions being off-label by FDA indications and 28.1% by BNF indications. Pregabalin was prescribed at a sub-therapeutic dose (75 mg/day) for neuropathic pain. Patient knowledge about gabapentinoids was found to be poor, particularly regarding side effects and drug interactions.

Conclusion

This study highlights the extensive off-label and sub-therapeutic use of gabapentinoids at Dhulikhel Hospital and reveals significant gaps in patient knowledge. This emphasizes the need for stricter prescribing guidelines, improved healthcare provider education, and better patient information to optimize the use and minimize risks. The frequent prescription of low-dose pregabalin for neuropathic pain raises the possibility that it may be used for night-time sedation rather than for pain management, indicating the need for further investigation.

Clinical predictors of treatment response to gabapentin in women with unexplained chronic pelvic pain

Introduction

Chronic pelvic pain affects up to 24% of women worldwide and for up to 55% of these there is no associated pathology. Despite this there are no established treatments in this cohort. This is a secondary analysis of a randomised-controlled trial (GaPP2) to explore if there are measures which enable us to predict treatment outcome.

Methods

GaPP2 recruited women with chronic pelvic pain and no identified pathology and compared the response to gabapentin and placebo. This analysis used variables collected at baseline including validated questionnaires. Binary logistic regression was used to create models to explore whether baseline variables predicted treatment response. Treatment response was determined using 30% reduction in average pain intensity, 30% reduction in worst pain intensity and the Patient Global Impression of Change ('marked' or 'very marked' improvement) individually. We also explored whether baseline variables predicted the occurrence of side-effects (dizziness, visual disturbances and drowsiness).

Results

Using the Patient Global Impression of Change questionnaire, we found a significant binary logistic regression (p = 0.029, explaining 31% of the variance), with those with lower worst pain intensity (odds ratio (OR) of 0.393, 95% CI [0.217, 0.712]), lower bladder symptom score (OR = 0.788, CI [0.628, 0.989]), and higher mental component quality of life score (OR = 0.911, CI [0.840, 0.988]), more likely to have 'marked' or 'very marked' improvement when treated with gabapentin. We could not identify predictors of experiencing side-effects to gabapentin. However, we did find predictors of these in the placebo group (binary logistic regression (p = 0.009) and explained 33% of the variance). Worse mental health (OR = 1.247, CI [1.019, 1.525]) and lower baseline pain interference (OR = 0.687, CI [0.483, 0.978]) were associated with having side effects, whilst the use of hormones reduced the risk of experiencing side effects (OR = 0.239, CI [0.084, 0.676]).

Discussion

Researchers and clinicians are increasingly aware of the importance of personalised medicine and treatment decisions being driven by knowledge of what treatments work for whom. Our data suggests an important role of the Patient Global Impression of Change in clinical trials as it may better reflect balance between symptoms reduction and side-effects and therefore be more useful in clinician-patients joint decision making.

Spinal cord stimulation for the treatment of complex regional pain syndrome: A systematic review of randomized controlled trials

Background

Spinal Cord Stimulation (SCS) is a widely recognized treatment for Complex Regional Pain Syndrome (CRPS), particularly in cases where traditional methods are ineffective. This paper systematically reviews randomized controlled trials to analyze the efficacy of SCS, as well as Dorsal Root Ganglion (DRG) Stimulation in treating CRPS, focusing on its long-term effectiveness.

Methods

This systematic review focused exclusively on randomized controlled trials to assess a primary outcome of improvement in pain symptoms in patients diagnosed with CRPS. The primary outcomes assessed were pain reduction and patient satisfaction, with attention to functional improvement, quality of life improvement, preference for waveform settings, and complications when such data was made available.

Results

The results showed significant pain reduction in CRPS patients treated with SCS and DRG. Preference for specific SCS settings varied among patients, with no clear superiority of one setting over another. Innovations in SCS technology, including novel waveforms and frequencies, demonstrated potential for enhanced efficacy and patient comfort.

Conclusions

The review underscores the importance of SCS and DRG as significant treatment options to reduce pain for patients suffering from CRPS. It highlights the need for ongoing research to optimize SCS therapy, focusing on individual patient preferences and responses to different stimulation parameters. This personalized approach could lead to improved patient outcomes in CRPS management. Additionally, as this study only contained data from Randomized Controlled Trials, inclusion of well-conducted observational studies may help to provide stronger evidence for use of this therapy in CRPS patients.

Assessing the efficacy of topical formulations in diabetic neuropathy: a narrative review

Background

We conducted a review of topical medications available for alleviation of diabetic neuropathic pain (DNP) and compared their efficacy with oral medications for pain relief. We also explored the feasibility of compounding topical medications.

Methods

Searches on PubMed, Medline Ovid, and Embase databases were conducted and findings were presented as a narrative review.

Results and discussion

8% Capsaicin patches and 5% Lidocaine patches had the most evidence. The literature also showed evidence for topical clonidine, gabapentin, and amitriptyline.

Conclusion

Topical formulations are a potential substitute to oral medications in patients suffering from DNP. Potential options include 8% Capsaicin patch, 5% Lidocaine patch, Clonidine gel, Topical gabapentin, and an amitriptyline and ketamine combination. A promising area of research that requires further study is the effect of a combination of topicals in alleviated DNP.

Off-label use of medicines in South Africa: a review

BACKGROUND

Off-label use of medicinal products has become an important part of mainstream and legitimate medical practice worldwide. This practice is common in oncology, obstetrics, paediatrics, and in the management of infectious diseases (notably HIV), and inflammatory conditions as well as in rare and/or orphan diseases. However, the off-label use of medicines recently-raised many clinical and legal difficulties, not only among medical practitioners but also among pharmacists and other healthcare professionals.

AIM

This paper, therefore, highlights the advantages (such as cost saving for both the patient and the country/insurance that is paying for the medication) and disadvantages (insufficient evidence available) of the use of medicines to treat specific conditions or indications for which they are currently not registered.

CONCLUSION

Off-label drug use can be likened to a double-edged sword, offering valuable opportunities for medical practitioners while carrying potential risks. When the scientific basis for off-label use is unclear, it may place patients at risk of unapproved experimentation, unforeseen health hazards, and ineffective treatments. Hence, there is a pressing need in South Africa for clear regulatory guidelines on off-label drug use. Additionally, the timely review and approval of new indications for medicines, backed by robust scientific evidence, are essential. This would reduce the significant burden and inherent risks faced by medical practitioners when using medicines off-label to provide compassionate care.

Psilocybin as a novel treatment for chronic pain

Psychedelic drugs are under active consideration for clinical use and have generated significant interest for their potential as anti-nociceptive treatments for chronic pain, and for addressing conditions like depression, frequently co-morbid with pain. This review primarily explores the utility of preclinical animal models in investigating the potential of psilocybin as an anti-nociceptive agent. Initial studies involving psilocybin in animal models of neuropathic and inflammatory pain are summarised, alongside areas where further research is needed. The potential mechanisms of action, including targeting serotonergic pathways through the activation of 5-HT2A receptors at both spinal and central levels, as well as neuroplastic actions that improve functional connectivity in brain regions involved in chronic pain, are considered. Current clinical aspects and the translational potential of psilocybin from animal models to chronic pain patients are reviewed. Also discussed is psilocybin's profile as an ideal anti-nociceptive agent, with a wide range of effects against chronic pain and its associated inflammatory or emotional components.

Complex regional pain syndrome after distal radius fracture: A survey of current practices

INTRODUCTION

Complex regional pain syndrome (CRPS) is a common complication following distal radius fractures that is difficult to diagnose and can lead to permanent disability. While various proposed prophylaxis and treatment modalities exist, high-quality evidence guiding practice is limited. This survey of Orthopaedic Trauma Association (OTA) and Canadian Orthopaedic Association (COA) members was conducted with the primary aim of assessing practice patterns in distal radius fractures complicated with CRPS.

METHODS

An electronic survey was distributed to practicing orthopaedic surgeons in the COA and OTA. Questions assessed practice setting, preference in management of distal radius fractures and CRPS, comfort level in managing CRPS, and identification of gaps in management. Responses were anonymized and collected over 8 months. Response data was analyzed using descriptive statistics; thematic analysis was used on free text response.

RESULTS

134 survey responses were completed. 84% of respondents felt the incidence of CRPS in distal radius fractures was 1-10%, while 15% felt it was closer to 11-20%. 24% of respondents utilized the "Budapest Criteria" to diagnose CRPS. 40% offered prophylaxis in patients felt to be at high risk of developing CRPS. 66% of surgeons felt neutral, uncomfortable, or very uncomfortable managing CRPS in distal radius fractures. When asked to consider adopting a prophylactic therapy, 38% of surgeons indicated that a therapy that reduced the absolute risk of CRPS by 6-10% would change their practice. Gaps in current practice included lack of evidence-based treatment and prevention strategies and diagnostic uncertainty.

CONCLUSION

This study identified that amongst orthopaedic surgeons in the COA and OTA, diagnosis, treatment, and prophylaxis strategies for CRPS in distal radius fractures are heterogeneous. Surgeons are not confident in their treatment of CRPS. Future studies using rigorous research methods are warranted to improve management.

Discovery of Antinociceptive α9α10 Nicotinic Acetylcholine Receptor Antagonists by Stable Receptor Expression

Chronic neuropathic pain is an increasingly prevalent societal issue that responds poorly to existing therapeutic strategies. The α9α10 nicotinic acetylcholine receptor (nAChR) has emerged as a potential target to treat neuropathic pain. However, challenges in expressing functional α9α10 nAChRs in mammalian cell lines have slowed the discovery of α9α10 ligands and studies into the relationship between α9α10 nAChRs and neuropathic pain. Here, we develop a cell line in the HEK293 background that stably expresses functional α9α10 nAChRs. By also developing cell lines expressing only α9 and α10 subunits, we identify distinct receptor pharmacology between homomeric α9 or α10 and heteromeric α9α10 nAChRs. Moreover, we demonstrate that incubation with nAChR ligands differentially regulates the expression of α9- or α10-containing nAChRs, suggesting a possible mechanism by which ligands may modify receptor composition and trafficking in α9- and α10-expressing cells. We then apply our α9α10 cell line in a screen of FDA-approved and investigational drugs to identify α9α10 ligands that provide new tools to probe α9α10 nAChR function. We demonstrate that one compound from this screen, diphenidol, possesses antinociceptive activity in a murine model of neuropathic pain. These results expand our understanding of α9α10 receptor pharmacology and provide new starting points for developing efficacious neuropathic pain treatments.

An overview of the non-procedural treatment options for peripheral neuropathic pain

Peripheral neuropathic pain is common in patients with peripheral nerve injury and can significantly impact both their function and quality of life. There is a wide variety of non-interventional treatment approaches, including pharmacologic therapy, physical/occupational therapy, modalities (therapeutic, mechanical, thermal, etc.), psychology, and lifestyle modification. First line pharmacologic therapy for peripheral neuropathic pain includes gabapentinoids, tricyclic antidepressants, and serotonin-norepinephrine reuptake inhibitors. Other classes of medications, such as topical treatments, opioids, and cannabinoids, have more limited usefulness in treatment but remain part of a treatment regimen. Physical and occupational therapy, psychological interventions, and lifestyle medicine are important adjuncts in the treatment and prevention of future peripheral neuropathic pain. The strength of the evidence supporting each intervention varies, with that for pharmacologic intervention being the strongest. A combination of these options tailored to the individual needs of the patient likely will result in the best treatment outcome for peripheral neuropathic pain.

Gabapentinoids and Risk of Hip Fracture

Importance

The increased use of gabapentinoids has been most pronounced in older people who are also susceptible to hip fractures.

Objective

To investigate the overall association between gabapentinoids and the risk of hip fractures and the stratified association across age groups, frailty status, and history of chronic kidney disease.

Design, Setting, and Participants

This was a case-case-time-control study in patients hospitalized for hip fracture in Victoria, Australia, between March 1, 2013, and June 30, 2018, with at least 1 prescription for a gabapentinoid before fracture. Conditional logistic regression was used to estimate the odds ratio (OR) and 95% CI for gabapentinoid dispensing in the index (1-60 days prefracture) compared with the reference (121-180 days prefracture) period. To adjust for the underlying time trend in gabapentinoid use, each index case was matched with up to 5 controls, selected from future cases of the same age and sex. Subgroup analyses were conducted in subgroups with or without chronic kidney disease (CKD), frailty scores less than 5, and frailty scores 5 and above. Frailty was computed using the Hospital Frailty Risk Score (HFRS). Data were analyzed from November 2023 to April 2024.

Exposure

Gabapentinoids (pregabalin or gabapentin).

Main Outcome and Measure

Hip fracture.

Results

Of 28 293 patients hospitalized for hip fractures, 2946 (1752 [59.5%] aged ≥80 years; 2099 [71.2%] female) were dispensed a gabapentinoid before hip fracture. Gabapentinoid dispensing was associated with increased odds of hip fractures (OR, 1.96; 95% CI, 1.66-2.32). After adjusting for the exposure-time trend and concomitant use of other central nervous system medications, the odds of hip fractures remained elevated (OR, 1.30; 95% CI, 1.07-1.57). The association between gabapentinoid dispensing and hip fracture was higher in patients with HFRS 5 and above (OR, 1.75; 95% CI, 1.31-2.33) and CKD (OR, 2.41; 95% CI, 1.65-3.52).

Conclusions and relevance

In this case-case-time-control study of Australian residents hospitalized for hip fracture, gabapentinoid use was associated with an increased risk of hip fractures, especially in patients who were frail or had chronic kidney disease. In addition to the known risk associated with kidney impairment, frailty status may be an important risk factor when considering use of gabapentinoids.

Modafinil Versus Amphetamine-Dextroamphetamine For Idiopathic Hypersomnia and Narcolepsy Type 2: A Randomized, Blinded, Non-inferiority Trial

BACKGROUND AND OBJECTIVE

Although there are several treatments for narcolepsy type 2 and idiopathic hypersomnia, studies that assess amphetamines, symptoms beyond sleepiness, and comparative effectiveness are needed. We performed a randomized, fully blinded, noninferiority trial of modafinil versus amphetamine-dextroamphetamine in these disorders.

METHODS

Forty-four adults were randomized to modafinil or amphetamine-dextroamphetamine, individually titrated to a maximum of modafinil 200 mg twice daily or amphetamine-dextroamphetamine 20 mg twice daily, for 12 weeks. Primary outcome was change in Epworth from baseline to week 12, with a noninferiority threshold of 2 points. Secondary outcomes were (1) patient global impression of change measures of disease severity, sleepiness, sleep inertia, and cognition; (2) change from baseline in Hypersomnia Severity Index; and (3) change from baseline in Sleep Inertia Questionnaire. Adverse events were compared between groups.

RESULTS

Epworth improved 5.0 [± standard deviation (SD) 2.7] points with modafinil and 4.4 (± SD 4.7) with amphetamine-dextroamphetamine; noninferiority of amphetamine-dextroamphetamine was not demonstrated (P = 0.11). Noninferiority of amphetamine-dextroamphetamine was demonstrated for change scores of severity, sleepiness, sleep inertia, Hypersomnia Severity Index, and Sleep Inertia Questionnaire. Dropouts due to adverse events were 31.8% for modafinil (including two severe events) and 9.1% for amphetamine-dextroamphetamine, P = 0.13. Anxiety was more common with modafinil and appetite suppression with amphetamine-dextroamphetamine.

CONCLUSION

Noninferiority of amphetamine-dextroamphetamine to modafinil was not demonstrated for the primary outcome. However, amphetamine-dextroamphetamine was noninferior on multiple secondary measures of disease severity and symptomatology. These data may inform shared decision-making regarding treatment for idiopathic hypersomnia and narcolepsy type 2.

REGISTRATION

Clinicaltrials.gov Registration (NCT03772314) 12/10/18. .

Patient-Directed Education to Promote Deprescribing: A Nonrandomized Clinical Trial

Importance

Patient-directed educational materials are a promising implementation strategy to expand deprescribing reach and adoption, but little is known about the impact across medication groups with potentially different perceived risks.

Objective

To examine the impact of a patient-directed education intervention on clinician deprescribing of potentially low-benefit (proton pump inhibitors) or high-risk medications (high-dose gabapentin, diabetes agents with hypoglycemia risks).

Design, Setting, and Participants

This pragmatic multisite nonrandomized clinical trial took place at 3 geographically distinct US Veterans Affairs (VA) medical centers from April 2021 to October 2022. The total study sample was composed of the intervention cohort and the historical control cohort cared for by 103 primary care practitioners (PCPs).

Intervention

The primary intervention component was a medication-specific brochure, mailed during the intervention time frame to all eligible patients 2 to 3 weeks prior to upcoming primary care appointments. Patients seen by the same PCPs at the same sites 1 year prior to the study intervention served as controls.

Main Outcome and Measures

The primary binary outcome variable was deprescribing 6 months after the intervention, defined as complete cessation or any dose reduction of the target medication using VA pharmacy dispensing data.

Results

The total study sample included 5071 patients. The overall rate of deprescribing among the intervention cohort (n = 2539) was 29.5% compared with 25.8% among the controls (n = 2532). In an unadjusted model, the intervention cohort was statistically significantly more likely to have deprescribing (odds ratio [OR], 1.17 [95% CI, 1.03-1.33]; P = .02). In a multivariable logistic regression model nesting patients within PCPs within sites and controlling for patient and PCP characteristics, the odds of deprescribing in the intervention cohort were 1.21 times that of the control cohort (95% CI, 1.05-1.38; P = .008). The difference in deprescribing prevalence between the intervention and control cohorts (proton pump inhibitors: 29.4% vs 25.4%; gabapentin: 40.2% vs 36.2%; hypoglycemia risk: 27.3% vs 25.1%) did not statistically significantly differ by medication group (P = .90).

Conclusion and Relevance

This nonrandomized clinical trial found that patient-directed educational materials provided prior to scheduled primary care appointments can effectively promote deprescribing for potentially low-benefit and high-risk medication groups.

Trial Registration

ClinicalTrials.gov Identifier: NCT0429490.

Repurposing prescribed hydromorphone: Alternative uses of safer supply and tablet-injectable opioid agonist treatment to meet unaddressed health needs

BACKGROUND

In response to the ongoing overdose crisis in Canada, a number of opioid agonist treatment and safer supply programs provide people at high overdose risk with daily-dispensed tablet hydromorphone, with some requiring witnessed ingestion and others providing take-away doses. While these programs are intended to reduce overdose events by limiting people's use of the contaminated drug supply, the experiences of people receiving hydromorphone vary. In this article we explore the ways people repurpose hydromorphone to address unmet needs.

METHODS

This article draws on in-depth qualitative interviews from two studies evaluating hydromorphone tablet distribution programs in British Columbia, Canada. We used thematic analysis to identify themes related to repurposing hydromorphone. We compared themes across the two studies to identify any similarities or differences in relation to the ways study participants discussed repurposing hydromorphone tablets. We utilize vignettes - snapshots of participant experiences - to analyse and represent the data.

RESULTS

Four vignettes demonstrate how hydromorphone tablets are often being used to address and resolve unmet needs of people who use drugs. While most participants reported reducing their use of illicit drugs, a variety of instrumental uses of tablet hydromorphone were also discussed, including reducing anxiety, addressing sleep issues, withdrawal management, and managing chronic pain.

CONCLUSION

Our findings demonstrate how people who use drugs are maximizing the benefits of tablet hydromorphone distribution to address unmet needs. Hydromorphone distribution programs represent a public health and harm reduction intervention that is usefully addressing experiences related to structural vulnerabilities (such as inadequate pain management), which are often overlooked amongst stigmatized groups.

Direct-to-Consumer Educational Brochures to Promote Gabapentinoid Deprescribing in Older Adults

This study examines gabapentinoid deprescribing using a novel approach of direct-to-consumer educational brochures intended to empower older adults to initiate a discussion on gabapentinoid risks and tapering.

Efficacy of gabapentin and pregabalin for treatment of post refractive surgery pain: a systematic review and meta-analysis

INTRODUCTION

For ophthalmic patients, eye discomfort is a major problem that requires efficient pain treatment techniques. Pregabalin and gabapentin have surfaced as viable treatments for post-refractive surgery pain. To manage pain after refractive surgery, gabapentin and pregabalin were evaluated in this systematic review and meta-analysis.

METHODOLOGY

A thorough search of databases including PubMed, Embase, Cochrane Library, and CINAHL was performed until March 2024. Inclusion criteria were randomized controlled trials assessing pregabalin and/or gabapentin's effectiveness in treating pain post-PRK, LASIK, and LASEK surgeries.

RESULTS

Six studies met inclusion criteria, comprising a total of 391 patients undergoing various corneal surgeries. The meta-analysis revealed that pregabalin was significantly more effective than placebo in reducing pain on the first and second postoperative days (SMD day 1: -0.32, 95% CI -0.54, -0.09; SMD day 2: -0.55, 95% CI -0.85, -0.25), while gabapentin showed significant pain reduction on the second day only (SMD day 2: -0.42, 95% CI -0.71, -0.13). Combined analysis for both medications showed significant pain reduction on the first- and second-days post-surgery. No significant increase in adverse events was associated with either medication. Publication bias was minimal except for a slight asymmetry noted on day 1 effectiveness.

CONCLUSION

Pregabalin and gabapentin are effective in reducing postoperative pain following refractive surgeries, with pregabalin showing a greater effect. Both medications are safe, with no significant increase in adverse events. Further research with standardized methodologies and long-term follow-up is recommended to optimize postoperative pain management in ocular surgeries.

RNA Interference Unleashed: Current Perspective of Small Interfering RNA (siRNA) Therapeutics in the Treatment of Neuropathic Pain

Neuropathic pain (NP) is one of the debilitating pain phenotypes that leads to the progressive degeneration of the central as well as peripheral nervous system. NP is often associated with hyperalgesia, allodynia, paresthesia, tingling, and burning sensations leading to disability, motor dysfunction, and compromised psychological state of the patients. Most of the conventional pharmacological agents are unable to improve the devastating conditions of pain because of their limited efficacy, undesirable side effects, and multifaceted pathophysiology of the diseased condition. A rapid rise in new cases of NP warrants further research for identifying the potential novel therapeutic modalities for treating NP. Recently, small interfering RNA (siRNA) approach has shown therapeutic potential in many disease conditions including NP. Delivery of siRNAs led to potential and selective downregulation of target mRNA and abolished the pain-related behaviors/pathophysiological pain response. The crucial role of siRNA in the treatment of NP by considering all of the pathways associated with NP that could be managed by siRNA therapeutics has been discussed. However, their therapeutic use is limited by several hurdles such as instability in systemic circulation due to their negative charge and membrane impermeability, off-target effects, immunogenicity, and inability to reach the intended site of action. This review also emphasizes several strategies and techniques to overcome these hurdles for translating these therapeutic siRNAs from bench to bedside by opening a new avenue for obtaining a potential therapeutic approach for treating NP.

High-Frequency 10-kHz Spinal Cord Stimulation Provides Long-term (24-Month) Improvements in Diabetes-Related Pain and Quality of Life for Patients with Painful Diabetic Neuropathy

BACKGROUND

The SENZA-PDN study evaluated high-frequency 10-kHz spinal cord stimulation (SCS) for the treatment of painful diabetic neuropathy (PDN). Over 24 months, 10-kHz SCS provided sustained pain relief and improved health-related quality of life. This report presents additional outcomes from the SENZA-PDN study, focusing on diabetes-related pain and quality of life outcomes.

METHODS

The SENZA-PDN study randomized 216 participants with refractory PDN to receive either conventional medical management (CMM) or 10-kHz SCS plus CMM (10-kHz SCS + CMM), allowing crossover after six months if pain relief was insufficient. Postimplantation assessments at 24 months were completed by 142 participants with a permanent 10-kHz SCS implant, comprising 84 initial and 58 crossover recipients. Measures included the Brief Pain Inventory for Diabetic Peripheral Neuropathy (BPI-DPN), Diabetes-Related Quality of Life (DQOL), Global Assessment of Functioning (GAF), and treatment satisfaction.

RESULTS

Over 24 months, 10-kHz SCS treatment significantly reduced pain severity by 66.9% (P < .001; BPI-DPN) and pain interference with mood and daily activities by 65.8% (P < .001; BPI-DPN). Significant improvements were also observed in overall DQOL score (P < .001) and GAF score (P < .001), and 91.5% of participants reported satisfaction with treatment.

CONCLUSIONS

High-frequency 10-kHz SCS significantly decreased pain severity and provided additional clinically meaningful improvements in DQOL and overall functioning for patients with PDN. The robust and sustained benefits over 24 months, coupled with high participant satisfaction, highlight that 10-kHz SCS is an efficacious and comprehensive therapy for patients with PDN.

Medication recommendations for treatment of lumbosacral radiculopathy: A systematic review of clinical practice guidelines

OBJECTIVE

The purpose of this systematic review was to ascertain guideline-recommended pharmaceutical approaches to lumbosacral radicular symptoms, assess the quality of the clinical practice guidelines (CPGs) with the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool, and qualitatively synthesize the guideline recommendations.

LITERATURE SURVEY

Literature searches were performed in PubMed, Cochrane Database of Systematic Reviews, Index to Chiropractic Literature, Allied and Complementary Medicine Database (AMED), Cumulative Index for Nursing and Allied Health Literature (CINAHL), and Physiotherapy Evidence Database (PEDro). We included guidelines published between January 1, 2017, and January 9, 2022, written in the English language, related to radiculopathy, sciatica, and/or low back pain with leg pain, and that provided recommendations on oral medication.

METHODOLOGY

The review was performed in accordance with Preferred Reporting Items for Systemic Reviews and Meta-Analyses (PRISMA) and the protocol was pre-registered with the International Prospective Register of Systematic Reviews (PROSPERO). Eligibility screening, full-text review, extraction of information pertaining to pharmacological management, and synthesis of results were performed independently by two authors and a third investigator was recruited to arbitrate any disagreements. The AGREE II tool was administered by four authors to appraise CPG quality.

SYNTHESIS

After screening 413 citations and assessing 37 full-text articles, 11 CPGs met the inclusion criteria. They represented seven countries (Belgium, Canada, England, France, Japan, Korea, and United States) and three continents (Asia, Europe, and North America), as well as the Global Spine Care Initiative aimed at a worldwide presence. The mean overall AGREE II score was 87.1% (standard deviation [SD] 12.6%), generally reflecting high-quality CPGs. The highest domain mean score was for Clarity of Presentation (96.7%, SD 4.4%), and the lowest was Applicability (75.6%, SD 22.8%). Five classes of medications were recommended by at least one CPG: anticonvulsants, antidepressants, oral corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs), and opioids.

CONCLUSIONS

The most common medication class recommended by the CPGs for lumbar radiculopathy was antidepressants. No CPGs recommended prescribing acetaminophen, benzodiazepines, muscle relaxants, or antibiotics. There was very little agreement between the CPGs, and all the medication classes had at least one CPG recommended against its use. Three guidelines reviewed did not recommend any medications due to lack of supporting literature, and instead recommended nonpharmacologic therapy.

Gabapentin alleviates peripheral nerve sensitization induced by inflammatory arthritis via ionotropic glutamate receptor NR2B subunit

Inflammatory arthritis leads to peripheral nerve sensitization, but the therapeutic effect is often unsatisfactory. Our preliminary studies have found that in mice with inflammatory arthritis, the use of ionotropic glutamate receptor antagonists can produce a good analgesic effect without altering foot swelling, suggesting that pain relief may be related to the improvement of neuropathic pain. However, the underlying mechanisms remain unclear. To further investigate the effects of neuropathic pain medications on inflammatory arthritis and the impact of the ionotropic glutamate receptor NR2B subunit (NR2B) on inflammatory arthritis, this study employed gabapentin (GBP) treatment on the inflammatory arthritis mouse model (the adjuvant induced arthritis, AIA), and we found a significant reduction in pain. Further studies revealed that in AIA, the expression levels of NR2B, TRPV1, pain-related molecules (substance P, PGE2), inflammatory cytokines (IL-1, IL-6, TNF-α, and GM-CSF) and Ca2+ were elevated in the foot and dorsal root ganglia (DRG). GBP treatment was able to influence the downregulation of the expression levels of NR2B, TRPV1, pain-related molecules, inflammatory cytokines and Ca2+. Mechanistic studies have shown that GBP treatment affects the downregulation of NR2B, and the downregulation of NR2B expression leads to the downregulation of TRPV1, pain-related molecules and inflammatory cytokines, thereby alleviating pain. These results suggest that in peripheral sensitization caused by AIA, GBP can play a role in improving pain, and NR2B may be a key target of peripheral nerve sensitization induced by inflammatory arthritis. GBP provides a theoretical basis for the clinical treatment of inflammatory arthritis.

Assessing suicide risk in chronic pain management: a narrative review across drug classes

INTRODUCTION

Chronic pain presents a multifaceted challenge in clinical practice, necessitating a nuanced understanding of pharmacological interventions to optimize treatment outcomes. This review provides an outline of various pharmacological agents commonly used in chronic pain management and highlights their safety considerations, particularly regarding suicide risk.

AREAS COVERED

This review discusses the role of antidepressants, anticonvulsants, GABA receptor agonists, NMDA receptor antagonists, corticosteroids, cannabis and cannabinoids, bisphosphonates, calcitonin, and alpha-2 adrenergic receptor agonists in chronic pain management. It assesses their therapeutic benefits, potential for misuse, and psychiatric adverse effects, including the risk of suicide. Each pharmacological class is evaluated in terms of its efficacy, safety profile, and considerations for clinical practice. We searched peer-reviewed English literature on the topic using the MEDLINE database without time restrictions.

EXPERT OPINION

While pharmacological interventions offer promise in alleviating chronic pain, healthcare providers must carefully weigh their benefits against potential risks, including the risk of exacerbating psychiatric symptoms and increasing suicide risk. Individualized treatment approaches, close monitoring, and multidisciplinary collaboration are essential for optimizing pain management strategies while mitigating adverse effects. Ongoing research efforts are crucial for advancing our understanding of these pharmacological interventions and refining pain management practices.

A Pathophysiological Approach for Selecting Medications to Treat Nociceptive and Neuropathic Pain in Servicemembers

INTRODUCTION

The prevalence of chronic pain of service members (SMs) in the U.S. is estimated to be higher (roughly 31-44%) compared to that of civilian population (26%). This higher prevalence is likely due to the high physical demands related combat and training injuries that are not immediately resolved and worsen over time. Mental Health America reports that chronic pain can lead to other mental health conditions such as severe anxiety, depression, bipolar disorder, and post-traumatic stress disorder. Such mental health conditions can negatively affect job performance, reduce readiness for military duties, and often lead to patterns of misuse of opioid after SMs entering civilian life. The primary objective of this narrative review is to present a summarized guideline for the treatment of two types of pain that likely affect SMs, namely nociceptive somatic pain and neuropathic pain. This review focused on a stepwise approach starting with nonopioid interventions prior to opioid therapy. The secondary objective of this review is to elucidate the primary mechanisms of action and pathways associated with these two types of pain.

METHODS

We followed the Scale for Assessment of Narrative Review Articles when transcribing this narrative review article to enhance the quality and brevity of this review. This Scale has 0.77% an intra-class coefficient of correlation, 95% confidence interval and 0.88 inter-rater reliability. We searched PubMed, Google Scholar, WorldCAT, and the Cochrane Library for the primary and secondary articles that targeted mechanisms of action, pathways, and pharmacological modalities for nociceptive somatic and neuropathic pain that were published from 2011 to 2022. We excluded articles related to pediatric, some specific pain conditions such as cancer-related pain, palliative care, end-of-life care, and articles that were not written in English language. For pharmacologic selection, we adopted the guidelines from the Policy for Implementation of a Comprehensive Policy on Pain Management by the Military Health Care system for the Fiscal Year 2021; the Clinical Practice Guidance for Opioid Therapy for Chronic Pain by the Department of Defense/Veterans Health Administration (2022); the (2021) Implementation of a Comprehensive Policy on Pain Management by the Military Health Care System; and the (2022) Guideline for Prescribing Opioids for Chronic Painby the Centers for Disease Control.

DISCUSSION

From the knowledge of the mechanisms of action and pathways, we can be more likely to identify the causative origins of pain. As a result, we can correctly diagnose the type of pain, properly develop an efficient and personalized treatment plan, minimize adverse effects, and optimize clinical outcomes. The guideline, however, does not serve as a substitute for clinical judgment in patient-centered decision-making. Medication choices should be individualized judiciously based on the patient's comorbid conditions, available social and economic resources, and the patient's preferences to balance the benefits and risks associated with various pain medications and to achieve optimal pain relief and improve the patient's quality of life.

Pharmacological Treatments for Methamphetamine Use Disorder: Current Status and Future Targets

The illicit use of the psychostimulant methamphetamine (METH) is a major concern, with overdose deaths increasing substantially since the mid-2010s. One challenge to treating METH use disorder (MUD), as with other psychostimulant use disorders, is that there are no available pharmacotherapies that can reduce cravings and help individuals achieve abstinence. The purpose of the current review is to discuss the molecular targets that have been tested in assays measuring the physiological, the cognitive, and the reinforcing effects of METH in both animals and humans. Several drugs show promise as potential pharmacotherapies for MUD when tested in animals, but fail to produce long-term changes in METH use in dependent individuals (eg, modafinil, antipsychotic medications, baclofen). However, these drugs, plus medications like atomoxetine and varenicline, may be better served as treatments to ameliorate the psychotomimetic effects of METH or to reverse METH-induced cognitive deficits. Preclinical studies show that vesicular monoamine transporter 2 inhibitors, metabotropic glutamate receptor ligands, and trace amine-associated receptor agonists are efficacious in attenuating the reinforcing effects of METH; however, clinical studies are needed to determine if these drugs effectively treat MUD. In addition to screening these compounds in individuals with MUD, potential future directions include increased emphasis on sex differences in preclinical studies and utilization of pharmacogenetic approaches to determine if genetic variances are predictive of treatment outcomes. These future directions can help lead to better interventions for treating MUD.

The Locus Coeruleus in Chronic Pain

Pain perception is the consequence of a complex interplay between activation and inhibition. Noradrenergic pain modulation inhibits nociceptive transmission and pain perception. The main source of norepinephrine (NE) in the central nervous system is the Locus Coeruleus (LC), a small but complex cluster of cells in the pons. The aim of this study is to review the literature on the LC-NE inhibitory system, its influence on chronic pain pathways and its frequent comorbidities. The literature research showed that pain perception is the consequence of nociceptive and environmental processing and is modulated by the LC-NE system. If perpetuated in time, nociceptive inputs can generate neuroplastic changes in the central nervous system that reduce the inhibitory effects of the LC-NE complex and facilitate the development of chronic pain and frequent comorbidities, such as anxiety, depression or sleeping disturbances. The exact mechanisms involved in the LC functional shift remain unknown, but there is some evidence that they occur through plastic changes in the medial and lateral pathways and their brain projections. Additionally, there are other influencing factors, like developmental issues, neuroinflammatory glial changes, NE receptor affinity and changes in LC neuronal firing rates.

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

Efficacy and Safety of Trazodone and Gabapentin Fixed-Dose Combination in Patients Affected by Painful Diabetic Neuropathy: Randomized, Controlled, Dose-Finding Study

INTRODUCTION

Up to 50% of diabetic patients with neuropathy suffer from chronic pain, namely painful diabetic neuropathy (PDN), an unmet medical need with significant impact on quality of life. Gabapentin is widely used for PDN, albeit with frequent dose-limiting effects. Trazodone, an antidepressant with multi-modal action, has shown promising results when given at low doses as an add-on to gabapentin. Upon previous clinical trials and experimental evidence, a fixed-dose combination (FDC) of both compounds, at low doses, was developed for neuropathic pain.

METHODS

This was a phase II, randomized, double-blind, placebo and reference controlled, dose-finding, multicenter, international, prospective study. Male and female diabetic patients aged 18-75 years and affected by PDN were eligible for enrolment. Patients were randomized (1:1:1:1:2 ratio) to trazodone and gabapentin (Trazo/Gaba) 2.5/25 mg t.i.d. for 8 weeks, Trazo/Gaba 5/50 mg t.i.d. for 8 weeks, Trazo/Gaba 10/100 mg t.i.d. for 8 weeks, gabapentin (Gaba), or placebo (PLB). The aim of the study was to collect preliminary information on the effect of the 3 different FDCs of Trazo/Gaba on pain intensity based on the 11-point numeric rating score (NRS) after 8 weeks of treatment. The secondary objectives were the evaluation of the percentage of responders, neuropathic pain symptoms, anxiety, sleep, quality of life, safety, and tolerability. The primary efficacy endpoint was evaluated with last observation carried out forward (LOCF), using an analysis of covariance (ANCOVA), including treatment and centers as factors and baseline as covariate and applying linear contrast test, excluding the active treatment. Only if the linear contrast test was significant (p < 0.05), the step-down Dunnett test would be used to determine the minimum effective dose significantly different from PLB. If linearity was not verified, an adjusted ANCOVA model and comparisons with Dunnett test were performed. Before the application of the ANCOVA model, the non-significance of interaction treatment per baseline was verified.

RESULTS

A total of 240 patients were included in the modified intention-to-treat (m-ITT) population: 39 in Trazo/Gaba 2.5/25 mg, 38 in Trazo/Gaba 5/50 mg, 37 in Trazo/Gaba 10/100 mg, 83 in PLB, and 43 in Gaba. After 8 weeks of treatment, changes of the average daily pain score based on the 11-point NRS from baseline were - 2.52 ± 2.31 in Trazo/Gaba 2.5/25 mg group, - 2.24 ± 1.96 in Trazo/Gaba 5/50 mg group, - 2.46 ± 2.12 in Trazo/Gaba 10/100 mg group, - 1.92 ± 2.21 in Gaba group, and - 2.02 ± 1.95 in the PLB group. The linear contrast test did not result in significant differences (p > 0.05) among treatment groups. Consequently, the minimum effective dose against PLB was not determined. The multiple comparison with Dunnett adjustment did not show any statistically significant differences vs. PLB after 8 weeks of treatment: Trazo/Gaba 2.5/25 mg (95% confidence interval (CI) - 1.2739, 0.2026; p = 0.1539); Trazo/Gaba 5/50 mg (95% CI - 0.9401, 0.5390; p = 0.5931); Trazo/Gaba 10/100 mg (95% CI - 1.0342, 0.4582; p = 0.4471). However, patients receiving the lowest dose of Trazo/Gaba 2.5/25 mg showed a statistically significant difference to PLB after 6 weeks of treatment (95% CI - 1.6648, - 0.2126; p = 0.0116). Positive results were also found for responder patients, other items related to the pain, anxiety, depression, sleep, and quality of life, consistently in favor to the lowest Trazo/Gaba FDC. Two serious adverse events (SAEs) occurred but were judged unrelated to the study treatment. Treatment-emergent adverse events (TEAEs) were mainly mild-to-moderate in intensity and involved primarily nervous system, gastrointestinal disorders, and investigations.

CONCLUSIONS

The primary end point of the study was the change from baseline of the average daily pain score based on the 11-point NRS after 8 weeks of treatment. While the primary endpoint was not reached, patients treated with Trazo/Gaba 2.5/25 mg t.i.d. showed statistically significant improvement of pain and other scores after 6 weeks and reported consistent better results in comparison to PLB on primary and secondary endpoints for the overall study duration. According to these results, the lowest dose of Trazo/Gaba FDC may be the best candidate for further clinical development to confirm the potential benefits of the FDC drug for this condition.

CLINICAL TRIAL REGISTRATION

NCT03749642.

Non-invasive Management of Head and Neck Neuralgia: A Literature Review

Head and neck neuralgia is a prevalent condition impacting millions worldwide, necessitating both invasive and non-invasive management strategies. This review focuses specifically on non-invasive approaches. Using the International Classification of Headache Disorders (ICHD-3), we categorized neuralgia causing head and neck pain to structure our literature search. Our review identified several non-invasive management techniques, including physiotherapy, pharmacological treatments, Pulsed Radiofrequency, local anesthesia blocks, Botulinum toxin injections, and non-invasive neuromodulation. This review highlights various effective non-invasive strategies for managing head and neck neuralgias, supported by studies published until 2023. These findings emphasize the clinical relevance of tailoring treatment plans to individual patient needs, considering the specific type of neuralgia and optimizing outcomes in clinical practice.

Chronic Neuropathic Pain and Comorbid Depression Syndrome: From Neural Circuit Mechanisms to Treatment

Chronic neuropathic pain and comorbid depression syndrome (CDS) is a major worldwide health problem that affects the quality of life of patients and imposes a tremendous socioeconomic burden. More than half of patients with chronic neuropathic pain also suffer from moderate or severe depression. Due to the complex pathogenesis of CDS, there are no effective therapeutic drugs available. The lack of research on the neural circuit mechanisms of CDS limits the development of treatments. The purpose of this article is to provide an overview of the various circuits involved in CDS. Notably, activating some neural circuits can alleviate pain and/or depression, while activating other circuits can exacerbate these conditions. Moreover, we discuss current and emerging pharmacotherapies for CDS, such as ketamine. Understanding the circuit mechanisms of CDS may provide clues for the development of novel drug treatments for improved CDS management.

The Association of Gabapentin Initiation with Cognitive and Behavioral Changes in Older Adults with Cognitive Impairment: A Retrospective Cohort Study

BACKGROUND

Although gabapentin has been increasingly prescribed to older adults, the relation between gabapentin initiation and longer-term neurocognitive changes is not well understood. Thus, this study aimed to examine the association of gabapentin initiation with cognitive and motor function decline in older adult participants with cognitive impairment.

METHODS

A retrospective cohort study was conducted using the National Alzheimer's Coordinating Center Uniform Data Set (2005-March 2023). Participants with cognitive impairment at the visit of gabapentin initiation (i.e., index visit) were included. Using the incidence density sampling method, up to nine non-users were randomly selected for each initiator. Cognitive decline over 1 year was defined as any increase in Clinical Dementia Rating global score (CDR®GLOB) or a 1-point increase in CDR® sum of boxes (CDR®SB). Functional status decline over 1 year was defined as at least a 3-point increase in the Functional Activities Questionnaire (FAQ) sum or a 0.3-point increase of mean of FAQ. Motoric decline over 1 year was defined as new clinician reports of gait disorder, falls, and slowness. To mitigate confounding and selection bias, joint stabilized inverse probability of treatment weights and censoring weights were used. Analyses compared index with index + 1 and index + 2 visits.

RESULTS

For the study of cognitive and functional status decline, we included 505 initiators (mean age [SD] 78.8 [7.4]; male = 45%) and 4545 non-users (79.2 [7.6]; 50.1%). For the study of motor decline, we included 353 initiators (78.3 [7.2]; 42.8%) and 3177 non-users (78.5 [7.4]; 48.1%). Gabapentin initiation was not statistically associated with decline on CDR®GLOB, CDR®SB, FAQ sum, or mean FAQ at the index + 1 or index + 2 visits. However, gabapentin initiation was significantly associated with increased odds of new falls at the index + 2 visit (odds ratio [95% confidence interval] 2.5 [1.3, 4.6]).

CONCLUSIONS

Over 1 or 2 years of follow-up, gabapentin initiation was not associated with decline in cognitive or functional status but was associated with increased odds of falling among research participants with cognitive impairment.

Secretory factors released from high dose radiation-activated osteoclasts increase the expression level of pain-associated neuropeptides in sensory neuronal cultures

Stereotactic Body Radiation Therapy for lung tumors near the chest wall often causes significant chest wall pain (CWP), negatively impacting patients' quality of life. The mechanisms behind SBRT-induced CWP remain unclear and may involve multiple factors. We investigated the potential crosstalk between radiation-activated osteoclasts and sensory neurons, focusing on osteoclast-derived factors in CWP. Using the murine pre-osteoclast cell line Raw264.7, we induced differentiation with RANKL, followed by 10Gy gamma-irradiation. Conditioned media from these irradiated osteoclasts was used to treat sensory neuronal cultures from mouse dorsal root ganglia. Neuronal cultures were also directly exposed to 10Gy radiation, with and without osteoclast co-culture. Analysis of osteoclast markers and pain-associated neuropeptides was conducted using RT-qPCR and histochemical staining. Osteoclast differentiation and activity were inhibited using Osteoprotegerin and risedronate. Results showed that high-dose radiation significantly increased osteoclast size, resorption pit size, and activity biomarkers. Neurons treated with CM from irradiated osteoclasts showed increased expression of pain-associated neuropeptides CGRP and Substance P, which was mitigated by osteoprotegerin and risedronate. This study suggests that high-dose radiation enhances osteoclast activity, upregulating pain-associated neuropeptides in sensory neurons, and that inhibitors like osteoprotegerin and risedronate may offer therapeutic strategies for managing radiation-induced pain.

Chronic pain, a narrative review for the internist in 2024

Chronic pain is a complex and pervasive condition that profoundly affects individuals physically, emotionally, and socially. This narrative review aims to provide internists and healthcare professionals with a comprehensive overview of chronic pain, its various types, pathophysiology, epidemiology, clinical presentation, evaluation tools, and the burden it imposes on patients. We discuss the importance of recognizing chronic pain as a legitimate condition and the need for a compassionate, individualized approach to management. The review highlights the role of both pharmacological and non-pharmacological interventions in treating chronic pain, emphasizing the value of reducing pain, improving function, enhancing quality of life, and minimizing medication dependence. Additionally, we touch upon the promising future of pain treatment, including advancements in technology and personalized medicine. While not a comprehensive systematic review, this article serves as a valuable resource for healthcare providers seeking to understand, manage, and treat chronic pain effectively in their daily practice.

Analgesia for rib fractures: a narrative review

PURPOSE

Rib fracture(s) is a common and painful injury often associated with significant morbidity (e.g., respiratory complications) and high mortality rates, especially in the elderly. Risk stratification and prompt implementation of analgesic pathways using a multimodal analgesia approach comprise a primary endpoint of care to reduce morbidity and mortality associated with rib fractures. This narrative review aims to describe the most recent evidence and care pathways currently available, including risk stratification tools and pharmacologic and regional analgesic blocks frequently used as part of the broadly recommended multimodal analgesic approach.

SOURCE

Available literature was searched using PubMed and Embase databases for each topic addressed herein and reviewed by content experts.

PRINCIPAL FINDINGS

Four risk stratification tools were identified, with the Study of the Management of Blunt Chest Wall Trauma score as most predictive. Current evidence on pharmacologic (i.e., acetaminophen, nonsteroidal anti-inflammatory drugs, gabapentinoids, ketamine, lidocaine, and dexmedetomidine) and regional analgesia (i.e., thoracic epidural analgesia, thoracic paravertebral block, erector spinae plane block, and serratus anterior plane block) techniques was reviewed, as was the pathophysiology of rib fracture(s) and its associated complications, including the development of chronic pain and disabilities.

CONCLUSION

Rib fracture(s) continues to be a serious diagnosis, with high rates of mortality, development of chronic pain, and disability. A multidisciplinary approach to management, combined with appropriate analgesia and adherence to care bundles/protocols, has been shown to decrease morbidity and mortality. Most of the risk-stratifying care pathways identified perform poorly in predicting mortality and complications after rib fracture(s).

An Apriori algorithm-based association rule analysis to identify acupoint combinations for treating uremic pruritus

Objective

Uremic pruritus (UP) is a prevalent and troublesome condition affecting individuals with end-stage renal failure, which results in intense pruritus, depression, as well as poor quality of sleep, significantly impacting their quality of life. According to previous studies, acupuncture and acupoint stimulation have been shown to provide additional benefits in treating UP in dialysis patients. In addition, using acupoints combination may yield superior effectiveness compared to utilizing a singular acupoint. To investigate the potential correlations between acupoint combinations, an association-rule analysis was employed.

Materials and Methods

Apriori algorithms stand out as highly potent techniques for identifying associations in databases; this study utilized an association rule mining to examine the association rules of key acupoint groupings that could be employed for treating UP.

Results

The analysis utilized information derived from the meta-analysis encompassing 40 randomized controlled trials that used acupuncture to treat UP. In total, 64 acupoints were analyzed, and 71 association rules were found. The following acupoint combinations: Auricular shenmen (TF4), Quchi (LI11), and Geshu (BL17); Auricular heart (Extra14), Sanyinjiao (SP6), and Auricular lung (CO14); and Auricular heart (Extra14), Xuehai (SP10), and Auricular lung (CO14) showed the strongest associations.

Conclusion

Acupoints involving Auricular shenmen (TF4), Quchi (LI11), Geshu (BL17), Auricular heart (Extra14), Sanyinjiao (SP6), Auricular lung (CO14), and Xuehai (SP10) can be regarded as the core combination of acupuncture points for managing UP.

Antineuropathic Pain Management After Orthopedic Surgery: A Systematic Review

Background

The opioid crisis has become a present concern in the medical field. In an effort to address these complications, antineuropathic pain medications have been considered as alternatives to prescribed opioids.

Objective

This review focuses on the analgesic effects of neuromodulators, such as gabapentin, duloxetine, and pregabalin, that provide room for less dependence on narcotic analgesics following orthopedic surgery.

Methods

During the database searches, 1,033 records were identified as a preliminary result. After duplicates were removed, an initial screen of each article was completed which identified records to be removed due to absence of a full-text article. Articles were excluded if they were not either prospective or retrospective, showcased an irrelevant medication (such as tricyclic antidepressants) which are not pertinent to this review, or deemed to be unrelated to the topic.

Results

Ultimately, 19 articles were selected. Three different drugs, gabapentin, pregabalin, and duloxetine, were analyzed to compile data on the effectiveness of preventing opioid overuse and addiction following hand surgery. This review identifies potential evidence that peri-operative gabapentin, pregabalin, and duloxetine administration decreases post-operative pain and lowers opioid dependency.

Conclusion

Gabapentin, pregabalin, and duloxetine have potential to further decrease post-operative pain and lower opioid dependency. This review creates an opening for further research in hand surgery to assess an updated protocol for pain management to reduce opioid dependency.

Clinical insights into traumatic injury of the inferior alveolar and lingual nerves: a comprehensive approach from diagnosis to therapeutic interventions

OBJECTIVES

This scoping review explores the risk and management of traumatic injuries to the inferior alveolar and lingual nerves during mandibular dental procedures. Emphasizing the significance of diagnostic tools, the review amalgamates existing knowledge to offer a comprehensive overview.

MATERIALS AND METHODS

A literature search across PubMed, Embase, and Cochrane Library informed the analysis.

RESULTS

Traumatic injuries often lead to hypo-/anesthesia and neuropathic pain, impacting individuals psychologically and socially. Diagnosis involves thorough anamnesis, clinical-neurological evaluations, and radiographic imaging. Severity varies, allowing for conservative or surgical interventions. Immediate action is recommended for reversible causes, while surgical therapies like decompression, readaptation, or reconstruction yield favorable outcomes. Conservative management, utilizing topical anesthesia, capsaicin, and systemic medications (tricyclic antidepressants, antipsychotics, and serotonin-norepinephrine-reuptake-inhibitors), proves effective for neuropathic pain.

CONCLUSIONS

Traumatic nerve injuries, though common in dental surgery, often go unrecorded. Despite lacking a definitive diagnostic gold standard, a meticulous examination of the injury and subsequent impairments is crucial.

CLINICAL RELEVANCE

Tailoring treatment to each case's characteristics is essential, recognizing the absence of a universal solution. This approach aims to optimize outcomes, restore functionality, and improve the quality of life for affected individuals.

A systematic review and network meta-analysis of pharmaceutical interventions used to manage chronic pain

It is estimated 1.5 billion of the global population suffer from chronic pain with prevalence increasing with demographics including age. It is suggested long-term exposure to chronic could cause further health challenges reducing people's quality of life. Therefore, it is imperative to use effective treatment options. We explored the current pharmaceutical treatments available for chronic pain management to better understand drug efficacy and pain reduction. A systematic methodology was developed and published in PROSPERO (CRD42021235384). Keywords of opioids, acute pain, pain management, chronic pain, opiods, NSAIDs, and analgesics were used across PubMed, Science direct, ProQuest, Web of science, Ovid Psych INFO, PROSPERO, EBSCOhost, MEDLINE, ClinicalTrials.gov and EMBASE. All randomised controlled clinical trials (RCTs), epidemiology and mixed-methods studies published in English between the 1st of January 1990 and 30th of April 2022 were included. A total of 119 studies were included. The data was synthesised using a tri-partied statistical methodology of a meta-analysis (24), pairwise meta-analysis (24) and network meta-analysis (34). Mean, median, standard deviation and confidence intervals for various pain assessments were used as the main outcomes for pre-treatment pain scores at baseline, post-treatment pain scores and pain score changes of each group. Our meta-analysis revealed the significant reduction in chronic pain scores of patients taking NSAID versus non-steroidal opioid drugs was comparative to patients given placebo under a random effects model. Pooled evidence also indicated significant drug efficiency with Botulinum Toxin Type-A (BTX-A) and Ketamine. Chronic pain is a public health problem that requires far more effective pharmaceutical interventions with minimal better side-effect profiles which will aid to develop better clinical guidelines. The importance of understanding ubiquity of pain by clinicians, policy makers, researchers and academic scholars is vital to prevent social determinant which aggravates issue.

Novel drugs affecting diabetic peripheral neuropathy

Diabetic peripheral neuropathy (DPN) poses a significant threat, affecting half of the global diabetic population and leading to severe complications, including pain, impaired mobility, and potential amputation. The delayed manifestation of diabetic neuropathy (DN) makes early diagnosis challenging, contributing to its debilitating impact on individuals with diabetes mellitus (DM). This review examines the multifaceted nature of DPN, focusing on the intricate interplay between oxidative stress, metabolic pathways, and the resulting neuronal damage. It delves into the challenges of diagnosing DN, emphasizing the critical role played by hyperglycemia in triggering these cascading effects. Furthermore, the study explores the limitations of current neuropathic pain drugs, prompting an investigation into a myriad of pharmaceutical agents tested in both human and animal trials over the past decade. The methodology scrutinizes these agents for their potential to provide symptomatic relief for DPN. The investigation reveals promising results from various pharmaceutical agents tested for DPN relief, showcasing their efficacy in ameliorating symptoms. However, a notable gap persists in addressing the underlying problem of DPN. The results underscore the complexity of DPN and the challenges in developing therapies that go beyond symptomatic relief. Despite advancements in treating DPN symptoms, there remains a scarcity of options addressing the underlying problem. This review consolidates the state-of-the-art drugs designed to combat DPN, highlighting their efficacy in alleviating symptoms. Additionally, it emphasizes the need for a deeper understanding of the diverse processes and pathways involved in DPN pathogenesis.

New Horizons in Diabetic Neuropathies: An Updated Review on their Pathology, Diagnosis, Mechanism, Screening Techniques, Pharmacological, and Future Approaches

BACKGROUND

One of the largest problems for global public health is diabetes mellitus (DM) and its micro and macrovascular consequences. Although prevention, diagnosis, and treatment have generally improved, its incidence is predicted to keep rising over the coming years. Due to the intricacy of the molecular mechanisms, which include inflammation, oxidative stress, and angiogenesis, among others, discovering treatments to stop or slow the course of diabetic complications is still a current unmet need.

METHODS

The pathogenesis and development of diabetic neuropathies may be explained by a wide variety of molecular pathways, hexosamine pathways, such as MAPK pathway, PARP pathway, oxidative stress pathway polyol (sorbitol) pathway, cyclooxygenase pathway, and lipoxygenase pathway. Although diabetic neuropathies can be treated symptomatically, there are limited options for treating the underlying cause.

RESULT

Various pathways and screening models involved in diabetic neuropathies are discussed, along with their possible outcomes. Moreover, both medicinal and non-medical approaches to therapy are also explored.

CONCLUSION

This study highlights the probable involvement of several processes and pathways in the establishment of diabetic neuropathies and presents in-depth knowledge of new therapeutic approaches intended to stop, delay, or reverse different types of diabetic complications.

Drug Repositioning: A Monetary Stratagem to Discover a New Application of Drugs

Drug repurposing, also referred to as drug repositioning or drug reprofiling, is a scientific approach to the detection of any new application for an already approved or investigational drug. It is a useful policy for the invention and development of new pharmacological or therapeutic applications of different drugs. The strategy has been known to offer numerous advantages over developing a completely novel drug for certain problems. Drug repurposing has numerous methodologies that can be categorized as target-oriented, drug-oriented, and problem-oriented. The choice of the methodology of drug repurposing relies on the accessible information about the drug molecule and like pharmacokinetic, pharmacological, physicochemical, and toxicological profile of the drug. In addition, molecular docking studies and other computer-aided methods have been known to show application in drug repurposing. The variation in dosage for original target diseases and novel diseases presents a challenge for researchers of drug repurposing in present times. The present review critically discusses the drugs repurposed for cancer, covid-19, Alzheimer's, and other diseases, strategies, and challenges of drug repurposing. Moreover, regulatory perspectives related to different countries like the United States (US), Europe, and India have been delineated in the present review.

Signal detection of adverse events associated with gabapentinoid use for chronic pain

INTRODUCTION

Gabapentinoids (GABA) prescribing as a potential and conceivably safer substitute for opioids has substantially increased. Understanding all potential adverse drug events (ADEs) associated with GABA will guide clinical decision-making for pain management.

METHODS

A 20% sample of Medicare enrollees with new chronic pain diagnoses in 2017-2018 was selected. GABA users were those with >=30 consecutive days prescription in a year without opioid prescription. Opioid users were similarly defined. The control group used neither of these drugs. Propensity score match across three groups based on demographics and comorbidity was performed. We used proportional reporting ratio (PRR), Gamma Poisson Shrinker, and tree-based scan statistic (TBSS) to detect ADEs within 3, 6, and 12 months of follow-up.

RESULTS

Immunity disorder was detected within 3 months of follow-up by PRR compared to opioid use (PRR:2.33), and by all three methods compared to controls. Complications of transplanted organs/tissues and schizophrenia spectrum/other psychotic disorders were consistently detected by PRR and TBSS within 3 months. Skin disorders were detected by TBSS; and stroke was detected by PRR within 3 months compared to opioid use (PRR:4.74). Some malignancies were detected by PRR within 12 months. Other signals detected in GABA users were neuropathy and nerve disorders.

CONCLUSIONS

Our study identified expected and unexpected ADE signals in GABA users. Neurological signals likely related to indications for GABA use. Signals for immunity, mental/behavior, and skin disorders were found in the FDA adverse event reporting system database. Unexpected signals of stroke and cancer require further confirmatory analyses to verify.

Research hotspots and trends on neuropathic pain-related mood disorders: a bibliometric analysis from 2003 to 2023

Introduction

Neuropathic Pain (NP) is often accompanied by mood disorders, which seriously affect the quality of life of patients. This study aimed to analyze the hotspots and trends in NP-related mood disorder research using bibliometric methods and to provide valuable predictions for future research in this field.

Methods

Articles and review articles on NP-related mood disorders published from January 2003 to May 2023 were retrieved from the Web of Science Core Collection. We used CiteSpace to analyze publications, countries, institutions, authors, cited authors, journals, cited journals, references, cited references, and keywords. We also analyzed collaborative network maps and co-occurrence network maps.

Results

A total of 4,540 studies were collected for analysis. The number of publications concerning NP-related mood disorders every year shows an upward trend. The United States was a major contributor in this field. The University of Toronto was the most productive core institution. C GHELARDINI was the most prolific author, and RH DWORKIN was the most frequently cited author. PAIN was identified as the journal with the highest productivity and citation rate. The current research hotspots mainly included quality of life, efficacy, double-blind methodology, gabapentin, pregabalin, postherpetic neuralgia, and central sensitization. The frontiers in research mainly focused on the mechanisms associated with microglia activation, oxidative stress, neuroinflammation, and NP-related mood disorders.

Discussion

In conclusion, the present study provided insight into the current state and trends in NP-related mood disorder research over the past 20 years. Consequently, researchers will be able to identify new perspectives on potential collaborators and cooperative institutions, hot topics, and research frontiers in this field.

Gabapentinoids: a therapeutic review

The Australian Therapeutic Goods Administration's approved indications for prescription of gabapentinoids are refractory focal epilepsy and neuropathic pain. Use of gabapentinoids outside of the approved indications is common, but evidence for this is limited, especially for chronic nonspecific back pain and nonradicular leg pain. Some effects of gabapentinoids encourage their nonmedical use (e.g. euphoria, sedation, disinhibition). Widespread nonmedical use has increased the incidence of accidental and deliberate poisonings. Dependence may develop with chronic use of gabapentinoids and abrupt cessation may induce withdrawal symptoms. If the indication for continued use is unclear, gradual dose tapering as a means of deprescribing is recommended. Clinicians should consider the indication, patient characteristics and harm-benefit profile when prescribing gabapentinoids. Some people, such as those with kidney disease, have an increased risk of harm when using these drugs.

Chemotherapy-Induced Peripheral Neuropathy: Diagnosis, Agents, General Clinical Presentation, and Treatments

PURPOSE OF REVIEW

This review aims to discuss pathophysiology, diagnosis, clinical presentation, and treatment of chemotherapy-induced peripheral neuropathy. Agent-specific presentation and pathophysiology is also being discussed.

RECENT FINDINGS

As new systemic oncological treatments continue to be developed, the number of cancer survivors continues to grow. Survivors are living longer with the long-term side effects of oncological treatments. We reviewed the pathophysiology of agent-specific chemotherapy-induced peripheral neuropathy and the updates in its treatment and preventative tools. Chemotherapy-induced peripheral neuropathy is a debilitating long-term side effect that often impairs cancer survivors' function and quality of life. The increasing life expectancy of cancer survivors has resulted in increased prevalence of this condition. Understanding its intricacies can provide physicians with better treatment tools and research opportunities to develop or identify new therapeutic agents.

5,7-Dimethoxycoumarin ameliorates vincristine induced neuropathic pain: potential role of 5HT3 receptors and monoamines

Vincristine is the drug of choice for Hodgkin's lymphoma, acute lymphoblastic leukemia, and non-Hodgkin lymphoma. Despite its significant anticancer effects, it causes dose-dependent neuropathy, leading to compulsive dose reduction. The available drugs used for vincristine-induced neuropathic pain (VINP) have a range of safety, efficacy, and tolerability issues prompting a search for new therapies. 5,7-Dimethoxycoumarin (5,7-DMC) also known as citropten, is a natural coumarin found in the essential oils of citrus plants such as lime, lemons, and bergamots, and it possesses both antidepressant and anti-inflammatory effects. This study was designed to investigate the possible analgesic and antiallodynic effects of 5,7-DMC in a murine model of VINP. Vincristine was administered to groups of BALB/c male mice (0.1 mg/kg intraperitoneally) once daily for 14 days to induce VINP. Thermal hyperalgesia and mechanical allodynia were quantified using the tail immersion test and von Frey filament application method. The levels of monoamine neurotransmitters and vitamin C in frontal cortical, striatal and hippocampal tissues, as well as the TNF-α level in plasma, were quantified using high performance liquid chromatography and ELISA respectively. On day 15 of the protocol, acute treatment with 5,7-DMC clearly reversed VINP thermal hyperalgesia, mechanical static allodynia, mechanical dynamic allodynia, and cold allodynia. The activity of 5,7-DMC against hyperalgesia and allodynia was inhibited by pretreatment with ondansetron but not naloxone, implicating a 5-HT3 receptor involvement. VINP vitamin C levels were restored by 5,7-DMC in the frontal cortex, and changes in serotonin, dopamine, adenosine, inosine and hypoxanthine levels caused by vincristine were reversed either fully or partially. Additionally, the vincristine-induced rise in hippocampal serotonin, dopamine, inosine and striatal serotonin was appreciably reversed by 5,7-DMC. 5,7-DMC also reversed the vincristine-induced increase in the plasma level of TNF-α. In negating the changes in the levels of some neurotransmitters in the brain caused by vincristine, 5,7-DMC showed stronger effects than gabapentin. It was concluded that, there is a potential role of 5-HT3 receptors and monoamines in the amelioration of VINP induced by 5,7-DMC, and the use of this compound warrants further investigation.

Translational evaluation of gait behavior in rodent models of arthritic disorders with the CatWalk device - a narrative review

Arthritic disorders have become one of the main contributors to the global burden of disease. Today, they are one of the leading causes of chronic pain and disability worldwide. Current therapies are incapable of treating pain sufficiently and preventing disease progression. The lack of understanding basic mechanisms underlying the initiation, maintenance and progression of arthritic disorders and related symptoms represent the major obstacle in the search for adequate treatments. For a long time, histological evaluation of joint pathology was the predominant outcome parameter in preclinical arthritis models. Nevertheless, quantification of pain and functional limitations analogs to arthritis related symptoms in humans is essential to enable bench to bedside translation and to evaluate the effectiveness of new treatment strategies. As the experience of pain and functional deficits are often associated with altered gait behavior, in the last decades, automated gait analysis has become a well-established tool for the quantitative evaluation of the sequalae of arthritic disorders in animal models. The purpose of this review is to provide a detailed overview on the current literature on the use of the CatWalk gait analysis system in rodent models of arthritic disorders, e.g., Osteoarthritis, Monoarthritis and Rheumatoid Arthritis. Special focus is put on the assessment and monitoring of pain-related behavior during the course of the disease. The capability of evaluating the effect of distinct treatment strategies and the future potential for the application of the CatWalk in rodent models of arthritic disorders is also addressed in this review. Finally, we discuss important consideration and provide recommendations on the use of the CatWalk in preclinical models of arthritic diseases.

Therapeutic Approach for Trigeminal Neuralgia: A Systematic Review

This umbrella review aimed to determine the various drugs used to treat trigeminal neuralgia (TN) and to evaluate their efficacies as well as side effects by surveying previously published reviews. An online search was conducted using PubMed, CRD, EBSCO, Web of Science, Scopus, and the Cochrane Library with no limits on publication date or patients' gender, age, and ethnicity. Reviews and meta-analyses of randomized controlled trials pertaining to drug therapy for TN, and other relevant review articles added from their reference lists, were evaluated. Rapid reviews, reviews published in languages other than English, and reviews of laboratory studies, case reports, and series were excluded. A total of 588 articles were initially collected; 127 full-text articles were evaluated after removing the duplicates and screening the titles and abstracts, and 11 articles were finally included in this study. Except for carbamazepine, most of the drugs had been inadequately studied. Carbamazepine and oxcarbazepine continue to be the first choice for medication for classical TN. Lamotrigine and baclofen can be regarded as second-line drugs to treat patients not responding to first-line medication or for patients having intolerable side effects from carbamazepine. Drug combinations using carbamazepine, baclofen, gabapentin, ropivacaine, tizanidine, and pimozide can yield satisfactory results and improve the tolerance to the treatment. Intravenous lidocaine can be used to treat acute exaggerations and botulinum toxin-A can be used in refractory cases. Proparacaine, dextromethorphan, and tocainide were reported to be inappropriate for treating TN. Anticonvulsants are successful in managing trigeminal neuralgia; nevertheless, there have been few studies with high levels of proof, making it challenging to compare or even combine their results in a statistically useful way. New research on other drugs, combination therapies, and newer formulations, such as vixotrigine, is awaited. There is conclusive evidence for the efficacy of pharmacological drugs in the treatment of TN.

Epirubicin and gait apraxia: a real-world data analysis of the FDA Adverse Event Reporting System database

Introduction: Epirubicin is widely used in many malignancies with good efficacy and tolerability. However, investigations about adverse events (AEs) using real-world information are still insufficient. Methods: We extracted Epirubicin-related reports submitted between the first quarter of 2014 and first quarter of 2023 from FAERS database. Four algorithms were utilized to evaluate whether there was a significant correlation between Epirubicin and AEs. Results: After de-duplicating, a total of 3919 cases were extracted. Among the 3919 cases, we identified 1472 AEs, 253 of which were found to be adverse drug reactions (ADRs) associated with Epirubicin. We analysed the occurrence of Epirubicin-induced ADRs and found several unexpected significant ADRs, such as hepatic artery stenosis, hepatic artery occlusion, intestinal atresia and so on. Interestingly, we found gait apraxia, a neurological condition, was also significantly associated with Epirubicin. To our knowledge, there haven't studies that have reported an association between gait disorders and the usage of epirubicin. Discussion: Our study identified new unexpected significant ADRs related to Epirubicin, providing new perspectives to the clinical use of Epirubicin.

Deprescribing interventions for gabapentinoids in adults: A scoping review

The emerging issue of rising gabapentinoid misuse is being recognized alongside the lack of current evidence supporting the safe and effective deprescribing of gabapentinoids. This scoping review aimed to assess the extent and nature of gabapentinoid deprescribing interventions in adults, either in reducing dosages, or prescribing of, gabapentinoids. Electronic databases were searched on 23 February 2022 without restrictions. Eligible studies included randomized, non-randomized and observational studies that assessed an intervention aimed at reducing/ceasing the prescription/use of a gabapentinoid in adults for any indication in a clinical setting. The research outcomes investigated the type of intervention, prescribing rates, cessations, patient outcomes and adverse events. Extracted outcome data were categorized as either short (≤3 months), intermediate (>3 but <12 months) or long (≥12 months) term. A narrative synthesis was conducted. The four included studies were conducted in primary and acute care settings. Interventions were of dose-reducing protocols, education and/or pharmacological-based approaches. In the randomized trials, gabapentinoid use could be ceased in at least one third of participants. In the two observational trials, gabapentinoid prescribing rates decreased by 9%. Serious adverse events and adverse events specifically related to gabapentinoids were reported in one trial. No study included patient-focused psychological interventions in the deprescribing process, nor provided any long-term follow-up. This review highlights the lack of existing evidence in this area. Due to limited available data, our review was unable to make any firm judgements on the most effective gabapentinoid deprescribing interventions in adults, highlighting the need for more research in this area.

An update to pain management after spinal cord injury: from pharmacology to circRNAs

Neuropathic pain (NP) following a spinal cord injury (SCI) is often hard to control and therapies should be focused on the physical, psychological, behavioral, social, and environmental factors that may contribute to chronic sensory symptoms. Novel therapeutic treatments for NP management should be based on the combination of pharmacological and nonpharmacological options. Some of them are addressed in this review with a focus on mechanisms and novel treatments. Several reports demonstrated an aberrant expression of non-coding RNAs (ncRNAs) that may represent key regulatory factors with a crucial role in the pathophysiology of NP and as potential diagnostic biomarkers. This review analyses the latest evidence for cellular and molecular mechanisms associated with the role of circular RNAs (circRNAs) in the management of pain after SCI. Advantages in the use of circRNA are their stability (up to 48 h), and specificity as sponges of different miRNAs related to SCI and nerve injury. The present review discusses novel data about deregulated circRNAs (up or downregulated) that sponge miRNAs, and promote cellular and molecular interactions with mRNAs and proteins. This data support the concept that circRNAs could be considered as novel potential therapeutic targets for NP management especially after spinal cord injuries.