An update on pharmacotherapy for the treatment of fibromyalgia

Ketamine in fibromyalgia: a systematic review

OBJECTIVE

Fibromyalgia (FM) subjects are treated with antidepressant agents; in most cases, these drugs lose efficacy or have adverse effects. Ketamine is an anesthetic drug used in FM in some studies. This article aims to systematically review the safety and efficacy of ketamine in fibromyalgia (FM) patients.

MATERIALS AND METHODS

We systematically searched articles on FM and ketamine published at Pubmed from 1966 to 2021. This study was registered at PROSPERO.

RESULTS

There were only 6 articles published in this field, with a total of 115 patients. The female sex was predominant (88 to 100%). The age varied from 23 to 53 years old. Disease duration ranged from 1 month to 28 years. The dosage of ketamine changed from 0.1 mg/kg-0.3-0.5 mg/kg in intravenous infusion (4/5) and subcutaneous application (1/5). Regarding outcomes, the Visual analog scale (VAS) before ketamine was from 59 to 100 mm and after treatment from 2 to 95 mm. Most short-term studies had a good response. Only the study with 8 weeks of follow-up did not observe a good response. Side effects were common; all appeared during the infusion and disappeared after a few minutes of the ketamine injection.

CONCLUSIONS

The present study demonstrates the effectiveness and safety of ketamine in FM patients in the short term. Although, more studies, including long-term follow-up studies, are still needed.

Pharmacological Treatment of Fibromyalgia Syndrome: A Practice-Based Review

PURPOSE OF REVIEW

Fibromyalgia Syndrome (FMS) is a complex chronic pain condition characterized by widespread musculoskeletal pain and numerous other debilitating symptoms. The purpose of this review is to provide a comprehensive overview, based on everyday clinical practice, of the drugs presently employed in the treatment of FMS.

RECENT FINDINGS

The treatment of FMS is based on a multimodal approach, with pharmacologic treatment being an essential pillar. The drugs used include tricyclic antidepressants, serotonin and noradrenaline reuptake inhibitors, other antidepressants, anticonvulsants, myorelaxants, and analgesics. The effectiveness of these medications varies, and the choice of drug often depends on the specific symptoms presented by the patient. Many drugs tend to either address only some domains of the complex FMS symptomatology or have a limited effect on pain. Each treatment option comes with potential side effects and risks that necessitate careful consideration. It may be beneficial to divide patients into clinical subpopulations, such as FMS with comorbid depression, for more effective treatment. Despite the complexities and challenges, the pharmacological treatment remains a crucial part for the management of FMS. This review aims to guide clinicians in prescribing pharmacological treatment to individuals with FMS.

The effect of earthquake on fibromyalgia: a comparison of patients on medication and without medication

INTRODUCTION / OBJECTIVES

Stressful events like earthquakes might worsen the symptoms of fibromyalgia, although the influence of medications on these consequences is yet uncertain. The objective of this study was to examine the influence of an earthquake on the symptoms of fibromyalgia and evaluate the impacts of medications used to treat fibromyalgia on the clinical picture.

METHOD

Ninety-five fibromyalgia patients were enrolled in a comparative study and divided into two groups: medication and non-medication. Three subcategories of medication groups were established: selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and gabapentinoid drugs (GDs). Before and after the earthquake, clinical evaluations were conducted using the Fibromyalgia Impact Questionnaire (FIQ), Hospital Anxiety and Depression Scale (HADS), and Jenkins Sleep Rating Scale (JSS). Statistical analyses were conducted to compare the scores before and after the earthquake and evaluate the differences between the groups.

RESULTS

Statistically significant increases were observed in FIQ, HADS-anxiety, HADS-depression, and JSS scores in the medication and non-medication groups before and after the earthquake comparisons (p < 0.05). Non-medication group reported significantly higher post-earthquake changes in FIQ, HADS-anxiety, HADS-depression, and JSS compared to the medication group (p < 0.05). While HADS-anxiety, HADS-depression, and JSS changes after the earthquake differed according to the drug subgroups (p < 0.05), no statistically significant difference was observed in FIQ values (p > 0.05). The highest scores were detected in the GD subgroup.

CONCLUSIONS

This study highlights the substantial impact of earthquakes on fibromyalgia patients. Medication use may assist in reducing the detrimental effects of stresses like earthquakes on fibromyalgia symptomatology. Future research with larger sample sizes and more extended follow-up periods is needed to explain these findings and optimize treatment regimens for fibromyalgia patients experiencing significant stressors.

Trajectory of Change in the Severity of Symptoms in Patients with Fibromyalgia over 24 Months: Exploratory Analyses of a Combination Pharmacological Intervention

Symptoms of fibromyalgia (FM) fluctuate and vary in severity. The current study aimed to evaluate the efficacy of palmitoylethanolamide (PEA) and acetyl-L-carnitine (ALC) in FM patients over a 24-month period and to investigate the mediating function of pain catastrophizing subdomains in unfavorable relationships with disease severity levels in patients with FM. Patients were evaluated at baseline, after 12 months, and after 24 months, using different patient-reported measures (FIQR, FASmod, PSD, and PCS) to distinguish different levels of FM disease severity. A reduction of 30% or more from baseline was considered clinically important ("markedly improved"). A multivariate analysis was performed to identify the variables predictive of an FIQR reduction. Twenty-two patients (28.6%) were classified as "markedly improved", 16 patients (20.8%) as "slightly/moderately improved", and 39 patients (50.6%) as "not improved." The FIQR, FASmod, and PSD scores were significantly reduced at 24 months. The pain magnification domain score of the PCS was the only variable predictive of worse FIQR scores (Wald coefficient: -2.94; p = 0.047). These results suggest a potential long-term therapeutic role for the PEA + ALC combination, with pain magnification being the primary predictor of poor efficacy.

Management of Fibromyalgia: An Update

Fibromyalgia, a chronic pain condition marked by abnormal pain processing, impacts a significant part of the population, leading to reduced quality of life and function. Hallmark symptoms include widespread persistent pain, sleep disturbances, fatigue, cognitive dysfunction, and mood changes. Through this updated review, we aim to contribute to the evolving understanding and management of fibromyalgia, offering insights into the diverse tools available to improve the lives of those affected by this challenging condition. Management begins with educating patients to ultimately relieve them of unnecessary testing and provide reassurance. Treatment emphasizes a comprehensive approach, combining nonpharmacological interventions such as aforementioned education, exercise, and psychotherapy, alongside pharmacologic management-namely duloxetine, milnacipran, pregabalin, and amitriptyline-which have consistent benefits for a range of symptoms across the spectrum of fibromyalgia. Notably, drugs like nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen are generally not recommended due to limited efficacy and associated risks. Lastly, a variety of other medications have shown promise, including NMDA-receptor antagonists, naltrexone, and cannabinoids; however, they should be used with caution due to a small amount of evidence and potential for adverse effects.

How to treat chronic pain in rheumatic and musculoskeletal diseases (RMDs) - A pharmacological review

INTRODUCTION

Chronic pain is a common symptom of rheumatic diseases that impacts patients' quality of life. While non-pharmacological approaches are often recommended as first-line treatments, pharmacological interventions are important for pain management. However, the effectiveness and safety of different pharmacological treatments for chronic pain in rheumatic diseases are unclear.

METHODS

This review critically synthesizes the current evidence base to guide clinicians in selecting appropriate pharmacological treatments for their patients, considering the expected benefits and potential risks and side effects.

RESULTS

For osteoarthritis, nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, opioids, and antidepressants are commonly used, with NSAIDs being the most recommended. In addition, topical agents, such as topical NSAIDs, are recommended for localized pain relief. For fibromyalgia, amitriptyline, serotonin and noradrenaline reuptake inhibitors (SNRIs), and gabapentinoids are commonly used, with SNRIs being the most recommended. For back pain, nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, opioids are used only for acute of flare-up pain, whereas neuropathic pain drugs are only used for chronic radicular pain. For inflammatory rheumatic diseases, disease-modifying antirheumatic drugs (DMARDs) and biological agents are recommended to slow disease progression and manage symptoms.

CONCLUSION

While DMARDs and biological agents are recommended for inflammatory rheumatic diseases, pharmacological treatments for other rheumatic diseases only alleviate symptoms and do not provide a cure for the underlying condition. The use of pharmacological treatments should be based on the expected benefits and evaluation of side effects, with non-pharmacological modalities also being considered, especially for fibromyalgia.

Fibromyalgia Animal Models Using Intermittent Cold and Psychological Stress

Fibromyalgia (FM) is a chronic pain condition characterized by widespread musculoskeletal pain and other frequent symptoms such as fatigue, sleep disturbance, cognitive impairment, and mood disorder. Based on the view that intermittent stress would be the most probable etiology for FM, intermittent cold- and intermittent psychological stress-induced generalized pain (ICGP and IPGP) models in mice have been developed and validated as FM-like pain models in terms of the patho-physiological and pharmacotherapeutic features that are shared with clinical versions. Both models show long-lasting and generalized pain and female-predominant sex differences after gonadectomy. Like many other neuropathic pain models, ICGP and IPGP were abolished in lysophosphatidic acid receptor 1 (LPAR1) knock-out mice or by LPAR1 antagonist treatments, although deciding the clinical importance of this mechanism depends on waiting for the development of a clinically available LPAR1 antagonist. On the other hand, the nonsteroidal anti-inflammatory drug diclofenac with morphine did not suppress hyperalgesia in these models, and this is consistent with the clinical findings. Pharmacological studies suggest that the lack of morphine analgesia is associated with opioid tolerance upon the stress-induced release of endorphins and subsequent counterbalance through anti-opioid NMDA receptor mechanisms. Regarding pharmacotherapy, hyperalgesia in both models was suppressed by pregabalin and duloxetine, which have been approved for FM treatment in clinic. Notably, repeated treatments with mirtazapine, an α2 adrenergic receptor antagonist-type antidepressant, and donepezil, a drug for treating Alzheimer's disease, showed potent therapeutic actions in these models. However, the pharmacotherapeutic treatment should be carried out 3 months after stress, which is stated in the FM guideline, and many preclinical studies, such as those analyzing molecular and cellular mechanisms, as well as additional evidence using different animal models, are required. Thus, the ICGP and IPGP models have the potential to help discover and characterize new therapeutic medicines that might be used for the radical treatment of FM, although there are several limitations to be overcome.

Hemokinin-1 is a mediator of chronic restraint stress-induced pain

The Tac4 gene-derived hemokinin-1 (HK-1) binds to the NK1 receptor, similarly to Substance P, and plays a role in acute stress reactions and pain transmission in mice. Here we investigated Tac4 mRNA expression in stress and pain-related regions and its involvement in chronic restraint stress-evoked behavioral changes and pain using Tac4 gene-deleted (Tac4-/-) mice compared to C57Bl/6 wildtypes (WT). Tac4 mRNA was detected by in situ hybridization RNAscope technique. Touch sensitivity was assessed by esthesiometry, cold tolerance by paw withdrawal latency from 0°C water. Anxiety was evaluated in the light-dark box (LDB) and open field test (OFT), depression-like behavior in the tail suspension test (TST). Adrenal and thymus weights were measured at the end of the experiment. We found abundant Tac4 expression in the hypothalamic-pituitary-adrenal axis, but Tac4 mRNA was also detected in the hippocampus, amygdala, somatosensory and piriform cortices in mice, and in the frontal regions and the amygdala in humans. In Tac4-/- mice of both sexes, stress-induced mechanical, but not cold hyperalgesia was significantly decreased compared to WTs. Stress-induced behavioral alterations were mild or absent in male WT animals, while significant changes of these parameters could be detected in females. Thymus weight decrease can be observed in both sexes. Higher baseline anxiety and depression-like behaviors were detected in male but not in female HK-1-deficient mice, highlighting the importance of investigating both sexes in preclinical studies. We provided the first evidence for the potent nociceptive and stress regulating effects of HK-1 in chronic restraint stress paradigm. Identification of its targets might open new perspectives for therapy of stress-induced pain.

Analysis of Japanese nationwide health datasets: association between lifestyle habits and prevalence of neuropathic pain and fibromyalgia with reference to dementia-related diseases and Parkinson's disease

OBJECTIVES

Chronic pain is defined as pain that persists or recurs for more than 3 months. This study focuses on neuropathic pain (NP) and fibromyalgia (FM) which are chronic pain states, and aims to identify lifestyle habits associated with their prevalence. Other neurological disorders are also analyzed as references.

METHODS

Association between the variable referring to disease prevalence (number of claims for reimbursement of marker drugs) and the variable for lifestyle habits/health examination results (collected from insured individuals aged 40-74 years) was determined by analyzing Japanese nationwide datasets, which were collected in 2018 and aggregated by prefecture. Pregabalin, donepezil, and levodopa were used as marker drugs for the chronic pain states, dementia-related diseases (Alzheimer's disease and Lewy body dementia) and Parkinson's disease (PD), respectively. Pearson's correlation analysis and multiple linear regression analysis were conducted.

RESULTS

Variables showing correlation coefficient (|r|)>0.5 were put into the multiple linear regression. Exercise habits (ꞵ=-0.3182), smoking habits (0.3218), daily drinking (0.2683), and alanine aminotransferase>51 U/L (0.2309) were finally incorporated in the equation for pregabalin (R 2=0.7268). Walking speed (-0.4543) and daily drinking (0.5077) were incorporated in the equation for donepezil (R 2=0.5718).

CONCLUSIONS

The prevalence of chronic pain states is associated with lifestyle habits, just like the dementia-related diseases. Exercise in daily life is negatively associated with the prevalence of the chronic pain states, although excessive alcohol drinking, smoking, and high serum ALT are positively associated with it. The prevalence of PD seems less associated with lifestyle habits.

Feasibility, Acceptability, and Preliminary Efficacy of a Positive Affect Skills Intervention for Adults With Fibromyalgia

Background and Objectives

To examine the feasibility, acceptability, and preliminary efficacy of a positive affect skills intervention for middle-aged and older adults with fibromyalgia syndrome (FMS).

Research Design and Methods

Ninety-five participants with FMS aged 50 and older (94% female) were randomized to 1 of 2 conditions: (a) Lessons in Affect Regulation to Keep Stress and Pain UndeR control (LARKSPUR; n = 49) or (b) emotion reporting/control (n = 46). LARKSPUR included 5 weeks of skill training that targeted 8 skills to help foster positive affect, including (a) noticing positive events, (b) savoring positive events, (c) identifying personal strengths, (d) behavioral activation to set and work toward attainable goals, (e) mindfulness, (f) positive reappraisal, (g) gratitude, and (h) acts of kindness. Outcome data were collected via online surveys at baseline, postintervention, and 1-month follow-up.

Results

Completion rates (88%) and satisfaction ratings (10-point scale) were high (LARKSPUR: M = 9.14, standard deviation (SD) = 1.49; control: M = 8.59, SD = 1.97). Improvements were greater in LARKSPUR participants compared with control participants on measures of positive affect (Cohen's d = 0.19 [0.15, 0.24]), negative affect (Cohen's d = -0.07 [-0.11, -0.02]), and pain catastrophizing (Cohen's d = -0.14 [-0.23, -0.05]). Improvements in positive affect (Cohen's d = 0.17 [0.13, 0.22]) and negative affect (Cohen's d = -0.11 [-0.15, -0.06]) were maintained at 1-month follow-up. Dose-response analyses indicated that intervention engagement significantly predicted pre-to-post and post-to-follow-up reductions in pain catastrophizing.

Discussion and Implications

The current preliminary findings add to existing literature and highlight the specific potential of internet-delivered positive affect skills programs for adults with FMS.

Clinical Trial Registration

NCT04869345.

What Do We Know about Nociplastic Pain?

Nociplastic pain is a recently distinguished type of pain, distinct from neuropathic and nociceptive pain, and is well described in the literature. It is often mistaken for central sensitization. Pathophysiology has not been clearly established with regard to alteration of the concentration of spinal fluid elements, the structure of the white and gray matter of the brain, and psychological aspects. Many different diagnostic tools, i.e., the painDETECT and Douleur Neuropathique 4 questionnaires, have been developed to diagnose neuropathic pain, but they can also be applied for nociplastic pain; however, more standardized instruments are still needed in order to assess its occurrence and clinical presentation. Numerous studies have shown that nociplastic pain is present in many different diseases such as fibromyalgia, complex regional pain syndrome type 1, and irritable bowel syndrome. Current pharmacological and nonpharmacological treatments for nociceptive and neuropathic pain are not entirely suitable for treating nociplastic pain. There is an ongoing effort to establish the most efficient way to manage it. The significance of this field has led to several clinical trials being carried out in a short time. The aim of this narrative review was to discuss the currently available evidence on pathophysiology, associated diseases, treatment possibilities, and clinical trials. It is important that physicians widely discuss and acknowledge this relatively new concept in order to provide optimized pain control for patients.

Efficacy, Tolerability, and Safety of Toludesvenlafaxine for the Treatment of Major Depressive Disorder-A Narrative Review

The estimated rate of treatment-resistant major depressive disorder (TRD) remains higher than 30%, even after the discovery of multiple classes of antidepressants in the last 7 decades. Toludesvenlafaxine (ansofaxine, LY03005, or LPM570065) is a first-in-class triple monoaminergic reuptake inhibitor (TRI) that has reached clinical use. The objective of this narrative review was to summarize clinical and preclinical evidence about the efficacy, tolerability, and safety of toludesvenlafaxine. Based on the results of 17 reports retrieved in the literature, the safety and tolerability profiles of toludesvenlafaxine were good in all clinical trials, and the pharmacokinetic parameters were well described in the phase 1 trials. The efficacy of toludesvenlafaxine was demonstrated in one phase 2 and one phase 3 trial, both on primary and secondary outcomes. In conclusion, this review highlights the favorable clinical results of toludesvenlafaxine in only two short-term trials that enrolled patients with major depressive disorder (MDD) (efficacy and tolerability were good for up to eight weeks), indicating the need for more good quality, larger-sample, and longer-term trials. Exploring new antidepressants, such as TRI, can be considered a priority for clinical research due to the high rates of TRD, but also due to the significant percentages of relapse in patients with MDD.

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.

Review of Fibromyalgia (FM) Syndrome Treatments

BACKGROUND

Fibromyalgia (FM) is a disease characterized by widespread musculoskeletal chronic pain that impairs the patient's quality of life and is considered a somatization disorder. The symptoms of the disease also affect the patient mentally, mainly since invisible pain is the only thing that indicates its existence. A typical symptom that characterizes FM patients is the lack of acceptance of the disease since its pathophysiology is not elucidated, hence the deficiencies in its management, or rather, cognitively, the belief that there is no disease to manage. The current paper aims to shed light on the new treatment methods at a holistic level, that is, cognitive, physical, and pharmacological therapies.

METHOD

A literature review was carried out that discusses treatment methods that help alleviate the pain, accept it, and manage the symptoms of the disease.

RESULTS

FM symptoms can be treated by taking a broad view of treatment that will include a response to the mind through pain management, response to the body through physical activity, and response to the pain through pharmacological treatment.

CONCLUSIONS

Today, there is an evolutionary view that accepts FM and chronic pain diseases as syndromes in which the pain is the disease; therefore, the response to this disease can be applied through three channels: physical, bodily, and mental.

Lessons in Affect Regulation to Keep Stress and Pain UndeR control (LARKSPUR): Design of a randomized controlled trial to increase positive affect in middle-aged and older adults with fibromyalgia

BACKGROUND

Fibromyalgia syndrome (FMS) is a leading cause of functional limitations and disability for which there is no cure. Positive psychological interventions for improving health have received increasing attention, but evidence of the feasibility, acceptability, and impact of such interventions in adult populations with FMS is limited.

OBJECTIVES

To describe the rationale and design of a 5-week, online positive affect skills intervention, LARKSPUR: Lessons in Affect Regulation to Keep Stress and Pain UndeR control.

METHODS

FMS participants (N = 90) will be randomized to one of two conditions: (1) LARKSPUR or (2) emotion reporting/attention control. LARKSPUR is an online multicomponent intervention that targets eight skills to help foster positive affect: (1) noticing positive events, (2) savoring positive events, (3) identifying personal strengths, (4) behavioral activation to set and work toward attainable goals, (5) mindfulness, (6) positive reappraisal, (7) gratitude, and (8) acts of kindness. The primary outcomes include feasibility (i.e., recruitment, retention, adherence) and acceptability (i.e., helpfulness, usability, satisfaction). Secondary outcomes include pain intensity and pain interference.

SIGNIFICANCE

If feasibility and acceptability metrics are met and reductions in pain outcomes are achieved, we will undertake future efficacy and effectiveness trials of LARKSPUR among older adults with FMS.

TRIAL REGISTRATION

NCT04869345.

Long-lasting reflexive and nonreflexive pain responses in two mouse models of fibromyalgia-like condition

Nociplastic pain arises from altered nociception despite no clear evidence of tissue or somatosensory system damage, and fibromyalgia syndrome can be highlighted as a prototype of this chronic pain subtype. Currently, there is a lack of effective treatments to alleviate both reflexive and nonreflexive pain responses associated with fibromyalgia condition, and suitable preclinical models are needed to assess new pharmacological strategies. In this context, although in recent years some remarkable animal models have been developed to mimic the main characteristics of human fibromyalgia, most of them show pain responses in the short term. Considering the chronicity of this condition, the present work aimed to develop two mouse models showing long-lasting reflexive and nonreflexive pain responses after several reserpine (RIM) or intramuscular acid saline solution (ASI) injections. To our knowledge, this is the first study showing that RIM6 and ASI mouse models show reflexive and nonreflexive responses up to 5-6 weeks, accompanied by either astro- or microgliosis in the spinal cord as pivotal physiopathology processes related to such condition development. In addition, acute treatment with pregabalin resulted in reflexive pain response alleviation in both the RIM6 and ASI models. Consequently, both may be considered suitable experimental models of fibromyalgia-like condition, especially RIM6.

Lidocaine in fibromyalgia: A systematic review

BACKGROUND

Fibromyalgia (FM) patients are treated with antidepressants, and in most cases, these drugs lose efficacy or present side effects. Intravenous lidocaine (IL) is an anesthetic drug used in some FM trials.

AIM

To systematically review the safety and efficacy of IL in FM patients.

METHODS

To systematically search PubMed for articles in English, Spanish, and Japanese with English Abstracts on FM and lidocaine between 1966 and February 2021. This study was registered at PROSPERO.

RESULTS

We found only ten articles published in this field, with a total of 461 patients. Females predominated varying from 95% to 100% in the studies. Age varied from 40.9 to 55 years old. Disease duration varied from 1 mo to 6.4 years. Lidocaine dose varied from 2 to 7.5 mg/kg via intravenous infusion. Follow-up period varied from 65.7 to 90 days. Regarding outcomes, most studies used the visual analogue scale (VAS) for pain; before short-term lidocaine administration, VAS was between 6.1 and 8.1 and after treatment was between 1.7 and 4.5 mm. Concerning long term lidocaine, VAS varied from 30% to 35.4% after lidocaine infusion. Side effects were observed in 0% to 39.6% of cases, they were usually mild or moderate.

CONCLUSION

This study demonstrates the short-term effectiveness and safety of intravenous lidocaine in FM patients. However, more studies, including long-term follow-up, are still needed.

Effectiveness of multicomponent treatment in patients with fibromyalgia: protocol for a systematic review and meta-analysis

BACKGROUND

The purpose of this protocol is to provide a new systematic review with meta-analysis using the current methodology to compare the effectiveness of multicomponent treatment versus other interventions for patients with fibromyalgia.

METHODS

This protocol conforms to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) and the recommendations of the Cochrane Collaboration Handbook. An electronic search will be conducted in MEDLINE, EMBASE, Web of Science, Cochrane CENTRAL, LILACS, CINAHL, and PEDro, from inception until April 2022. There will be no language restrictions. The Cochrane Collaboration tool for assessing the risk of bias (RoB2) will be used. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) scale will be used to evaluate the strength of the evidence. The Hartung-Knapp-Sidik-Jonkman random effects or Mantel-Haenszel fixed effects methods will be used, depending on the heterogeneity, to compute a pooled estimate of the mean difference (MD) or standardized mean difference (SMD) and respective 95% confidence intervals for clinical outcomes.

DISCUSSION

This systematic review will synthesize evidence on the effectiveness of multicomponent treatment in patients with fibromyalgia and could add important evidence in the treatment of FM to improve clinical practice and decision-making/actions in this field. This new systematic review will try to show the effects of multicomponent treatment by type (endurance, resistance, stretching, or mind-body exercises [pilates or taichi]) and intensity (light, moderate, moderate-to-vigorous, vigorous) of exercise in patients with FM. The results will be disseminated by publication in a peer-reviewed journal. Ethics approval will not be needed because the data used for this systematic review will be obtained from individual trials and there will be no concerns about privacy. However, if we identify ethical issues during the development of the systematic review, these findings will be reported in the discussion of the study.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020142082.

Milnacipran for the Treatment of Fibromyalgia

Purpose of review

This is a comprehensive review of the literature regarding the use of milnacipran in treating fibromyalgia. A chronic pain disorder with other system disturbances, fibromyalgia is often resistant to many therapeutic approaches. This review presents the background, evidence, and indications for using milnacipran as a treatment option for this condition.

Recent Findings

The definition of fibromyalgia has evolved over many years as it is a relatively tricky syndrome to measure objectively. Today, it is characterized by chronic, widespread pain accompanied by alterations in sleep, mood, and other behavioral aspects. A variety of therapeutic regimens currently used to treat the syndrome as a singular approach are rarely effective.Milnacipran is one of three drugs currently approved by the FDA for the treatment of fibromyalgia. It acts as a serotonin and norepinephrine reuptake inhibitor, which results in decreased pain transmission. Milnacipran remains an effective treatment option for fibromyalgia in adults and needs to be further evaluated with existing therapeutic approaches.

Summary

Fibromyalgia is a broad-spectrum disorder primarily characterized by chronic pain coupled with disturbances in cognitive functioning and sleep. The progression of this syndrome is often debilitating and significantly affects the quality of life. Milnacipran is one of three FDA-approved drugs used to alleviate the symptom burden and is comparatively more therapeutic in specific domains of fibromyalgia. A more holistic approach is needed to treat fibromyalgia effectively and further research, including direct comparison studies, should be conducted to fully evaluate the usefulness of this drug.

Diagnostic Challenges and Management of Fibromyalgia

The World Health Organization regards chronic pain to be a public health concern. In clinical medicine, fibromyalgia (FM) is the most prevalent chronic widespread pain disease. In terms of impairment, consumption of health and social resources, and impact on primary and speciality care systems, it has reached worrisome proportions. This disease is frequently managed by primary care providers. Because of its intricacy, fibromyalgia diagnosis and treatment can be difficult. Fibromyalgia is a controversial condition. It might appear ill-defined in comparison to other pain conditions, with no clear knowledge of pathophysiology and hence no particular targeted therapy. This invariably sparks debates and challenges. There is no obvious cut-off point that distinguishes FM from non-FM. The diagnosis of fibromyalgia has been complicated by several factors, including patients' health-seeking behaviour, symptom identification, and physician labelling of the disease. Fibromyalgia is currently considered a centralized pain condition, according to research that has improved our understanding of its etiopathology. A multidisciplinary strategy combining pharmacological and non-pharmacological therapies based on a biopsychosocial paradigm can result in effective therapy. Cultural and psychosocial variables appear to be a recent development in fibromyalgia, and they appear to have a larger influence on physician diagnosis than severe symptom levels in FM patients. Although physicians rely on FM criteria as the only way to classify FM patients in research and clinical settings, some crucial elements of the diagnostic challenge of fibromyalgia remain unsolved - invalidation, psychosocial variables, and diverse illness manifestation are some examples. Beyond the existing constructional scores, physicians' judgment gained in real communicative contexts with patients, appears to be the only dependable route for a more accurate diagnosis for fibromyalgia. We have performed an exhaustive review of the literature using the keywords "Fibromyalgia", "challenges" and "diagnosis" in PubMed and Google Scholar indexes up to September 2021. This article aims to examine the causes, diagnosis, and current treatment protocols of FM, as well as discuss some continuing debates and diagnostic challenges which physicians face in accurately diagnosing fibromyalgia.

Cognitive behavioral therapy for insomnia (CBT-i) in patients with fibromyalgia: a systematic review and meta-analysis

PURPOSE

We aimed to evaluate the effectiveness of CBT-i in patients with fibromyalgia in comparison with other non-pharmacological treatments.

METHODS

Randomized controlled trials assessing the effects of CBT-i in adults with fibromyalgia, published in English or Spanish, were eligible. Electronic searches were performed using PubMed, Scopus, The Cochrane Library, WebOfKnowledge and Psicodoc databases in March 2021. The main outcome measures were sleep efficiency and sleep quality. Secondary outcomes included pain, depression, and anxiety.

RESULTS

Of 226 studies reviewed, five were included in the meta-analysis. CBT-i compared with non-pharmacological treatments showed no significant improvements in sleep efficiency (p = 0.05; standardized mean difference (SMD) [95% CI] 0.31 [-0.00 to 0.61]). CBT-i showed significant improvements in sleep quality (p = 0.009; SMD [95% CI] - 0.53 [-0.93 to -0.13]), pain (p = 0.002; SMD [95% CI] - 0.41 [-0.67 to -0.16]), anxiety (p = 0.001; SMD [95% CI] - 0.46 [-0.74 to 0.18]) and depression (p = 0.02; SMD [95% CI] - 0.33 [-0.61 to -0.05]), compared to non-pharmacological treatments. Effect sizes ranged from small to moderate.

CONCLUSIONS

CBT-i was associated with a significant improvement in sleep quality, pain, anxiety, and depression, although these results are retrieved from very few studies with only very low to low quality evidence. Trial registration: The review protocol was registered with PROSPERO (Record ID = CRD42016030161).IMPLICATIONS FOR REHABILITATIONCBT-i has been proven to improve sleep quality, pain, anxiety and depression, although with small effect sizes.Implementing hybrid CBT for pain and sleep or combining CBT and mindfulness may improve symptoms in people diagnosed with FM.This meta-analysis results highlight the need to enhance sleep management skills among people suffering from this health condition.

Nociplastic pain: towards an understanding of prevalent pain conditions

Nociplastic pain is the semantic term suggested by the international community of pain researchers to describe a third category of pain that is mechanistically distinct from nociceptive pain, which is caused by ongoing inflammation and damage of tissues, and neuropathic pain, which is caused by nerve damage. The mechanisms that underlie this type of pain are not entirely understood, but it is thought that augmented CNS pain and sensory processing and altered pain modulation play prominent roles. The symptoms observed in nociplastic pain include multifocal pain that is more widespread or intense, or both, than would be expected given the amount of identifiable tissue or nerve damage, as well as other CNS-derived symptoms, such as fatigue, sleep, memory, and mood problems. This type of pain can occur in isolation, as often occurs in conditions such as fibromyalgia or tension-type headache, or as part of a mixed-pain state in combination with ongoing nociceptive or neuropathic pain, as might occur in chronic low back pain. It is important to recognise this type of pain, since it will respond to different therapies than nociceptive pain, with a decreased responsiveness to peripherally directed therapies such as anti-inflammatory drugs and opioids, surgery, or injections.

Juvenile primary fibromyalgia syndrome: A Review- Treatment and Prognosis

Juvenile primary fibromyalgia syndrome (JPFS) is a chronic musculoskeletal pain syndrome affecting children and adolescents. In part one of this review, we discussed the epidemiology, etiology, pathogenesis, clinical manifestations and diagnosis of JPFS. Part two focuses on the treatment and prognosis of JPFS. Early intervention is important. The standard of care is multidisciplinary, combining various modalities-most importantly, exercise and cognitive behavioral therapy. Prognosis varies and symptoms may persist into adulthood.

Mirogabalin, a novel ligand for α2δ subunit of voltage-gated calcium channels, improves cognitive impairments in repeated intramuscular acidic saline injection model rats, an experimental model of fibromyalgia

Mirogabalin is a novel potent and selective ligand for the α₂δ subunit of voltage-gated calcium channels, and shows potent and sustained analgesic effects in neuropathic pain and fibromyalgia models. Fibromyalgia is often associated with multiple comorbid symptoms, such as anxiety, depression and cognitive impairment. In the present study, we investigated the effects of mirogabalin on cognitive impairments in an experimental animal model for fibromyalgia, repeated intramuscular acidic saline injection model (Sluka model) rats. Male rats received two repeated intramuscular injections of pH 4 acidic saline into their gastrocnemius muscle. After developing mechanical hypersensitivity as identified in the von Frey test, the animals received the test substance orally once daily for 13 days and were subjected to four cognitive function tests, (Y-maze, novel object recognition, Morris water maze and step-through passive avoidance). Sluka model rats showed cognitive impairments in all four tests. Oral administration of mirogabalin (3 and 10 mg/kg) improved the cognitive impairments in these rats. In conclusion, mirogabalin improved the impaired cognitive function in Sluka model rats. It may thus also alleviate cognitive impairments as well as painful symptoms in fibromyalgia patients.

Efficacy of cannabinoids in fibromyalgia: a literature review

Fibromyalgia is a chronic disease of unclear etiology, involving a neural oversensitization and impaired pain modulation, in addition to a clinical deficiency of the endocannabinoid system. Fibromyalgia is associated with a number of somatic and psychological disorders and hence multiple pharmacological approaches have been used, including   opioids, antidepressants, antiepileptics, and more recently medical cannabis. This narrative review comprises a review of the current literature on the efficacy of   cannabinoids in fibromyalgia. The studies describe a possible influence of cannabis on pain control in patients with fibromyalgia, with positive effects on quality of life and sleep. The use of cannabis seems to be beneficial in patients with fibromyalgia; however, more robust studies are still needed to establish is actual efficacy in pain management, quality of life and improvement of associated symptoms.

Pool-based exercise for amelioration of pain in adults with fibromyalgia syndrome: A systematic review and meta-analysis

OBJECTIVE

To evaluate the effects of pool-based exercises on pain symptomatology among adults with fibromyalgia syndrome.

METHODS

A systematic review and meta-analysis were carried out using PRISMA guidelines. Database search was conducted by two independent reviewers. For meta-analysis, the visual analogue scale (VAS) score for pain was used as the primary outcome and the Fibromyalgia Impact Questionnaire (FIQ) score was utilized as the secondary outcome.

RESULTS

A total of 42 out of 292 potentially eligible studies were selected for being read in full by reviewers, 14 of which were included in meta-analysis, being 10 of them used in sensitivity analysis of either the primary or secondary outcome. Data pooled from 10 randomized controlled trials (n = 508) revealed that patients who underwent pool-based exercises exhibited a significantly lower mean in VAS score as compared to controls (SMD = -0.27, 95% CI: -0.45 to -0.09). Regarding FIQ scores, data from 10 randomized controlled trials were pooled (n = 578) and a lower mean score was also shown in the group that underwent a pool-based exercise program (SMD = -0.29, 95% CI: -0.49 to -0.09). Limitations of this study include the small sample size and moderate dropout rates in currently available clinical trials.

CONCLUSION

Pool-based exercise may provide some additional benefit for pain relief in adults with fibromyalgia as compared to either land-based or no physical exercise.

IMPLICATIONS OF KEY FINDINGS

Collectively, these findings suggest that pool-based exercise deserves further attention as a potential adjuvant therapeutic option for adults with fibromyalgia. PROSPERO registration number: CRD42019136755.

Fibromyalgia: Recent Advances in Diagnosis, Classification, Pharmacotherapy and Alternative Remedies

Fibromyalgia (FM) is a syndrome that does not present a well-defined underlying organic disease. FM is a condition which has been associated with diseases such as infections, diabetes, psychiatric or neurological disorders, rheumatic pathologies, and is a disorder that rather than diagnosis of exclusion requires positive diagnosis. A multidimensional approach is required for the management of FM, including pain management, pharmacological therapies, behavioral therapy, patient education, and exercise. The purpose of this review is to summarize the recent advances in classification criteria and diagnostic criteria for FM as well as to explore pharmacotherapy and the use of alternative therapies including the use of plant bioactive molecules.

Use of Complementary and Alternative Medicine in Fibromyalgia: Results of an Online Survey

BACKGROUND

Fibromyalgia is a chronic condition which may negatively impact various aspects of patients' lives. Many people with fibromyalgia look to complementary and alternative medicine treatments for symptom relief.

AIMS

The three main objectives of this study were to examine self-reported complementary and alternative medicine use in patients with fibromyalgia, to determine associations between the use of complementary and alternative medicine treatments and patients' self-reported quality of live and self-reported pain levels.

DESIGN

Cross-sectional survey.

SETTING

Web-based.

PARTICIPANTS/SUBJECTS

Adults over the age of 18 years who had been diagnosed with fibromyalgia.

METHODS

Patients with fibromyalgia responded to an online questionnaire regarding the following: treatments (complementary and alternative medicine, prescription and over-the-counter medications), quality of life (Quality of Life Scale-16), assessment of current pain (visual analog scale), and demographic information.

RESULTS

Approximately 66% of the respondents used complementary and alternative treatments. Vitamins, massage therapy, and meditation were the most commonly used complementary and alternative therapies. Results indicated respondents using a combination of complementary and alternative medicine and pharmacologic treatments (prescription or over-the-counter) had significantly higher quality of life versus those using pharmacologic treatments alone, p = .011. Similarly, respondents using only complementary and alternative medicine treatment reported significantly lower pain levels versus those using pharmacologic treatment alone, p = .046.

CONCLUSIONS

The study suggests that a large proportion of fibromyalgia patients use complementary and alternative medicine, and these treatments may offer beneficial effects to these patients. Integration of complementary and alternative medicine into conventional treatment regimens may provide opportunities for a holistic treatment approach and greater symptom relief for fibromyalgia patients. This approach is timely, as controlled substances are increasingly difficult for patients with fibromyalgia to access.

Prevalence of obstructive sleep apnea in female patients with fibromyalgia

Objectives:

To determine the prevalence of obstructive sleep apnea in female patients with fibromyalgia (FM) presenting to physical therapy outpatient clinics.

Methods:

The 36-item short form health survey (SF-36) questionnaire, Berlin test, and epworth sleepiness scale were administered, along with a polysomnography to 38 female patients. This cross-sectional study comprised diagnosed with FM according to the diagnostic criteria of the American College of Rheumatology, between March 2017 and August 2019, at the Faculty of Medicine Hospital, Çanakkale Onsekiz Mart University, Çanakkale, Turkey.

Results:

Of the participants, 65.9% were found to have obstructive sleep apnea (OSA). Patients with OSA were older and had a higher disease activity score for FM. A strong positive correlation was identified between the apnea-hypopnea index (AHI) and the FA disease activity score. A negative correlation was found between AHI and the subscales of SF-36.

Conclusion:

A clinical assessment of female patients with FM requires a multidisciplinary approach, and patients with excessive daytime sleepiness in particular are recommended to undergo polysomnography. The authors believe that the early detection and treatment of accompanying OSA will contribute not only to the quality of life, but also to the survival of patients with FM.

Persistence of pregabalin treatment in Taiwan: a nation-wide population-based study

Background

Pregabalin is approved for the treatment of neuropathic pain, fibromyalgia, and seizure disorders, although the pivotal trials were mostly carried out in Europe or North America. The prescribing patterns among different indications in Asia have rarely been explored.

Methods

This was a population-based retrospective cohort study based on the National Health Insurance Research Database in Taiwan. Prescriptions of pregabalin were identified, and data regarding demographics, indications, co-existing diagnoses, and concomitant medications were extracted. Pregabalin users were followed for at least one year, and factors associated with persistence at one year were determined by using multivariate logistic regression analysis.

Results

Between June 2012 and December 2016, 114,437 pregabalin users (mean age 60.7 ± 15.4 years, 57.8% female) were identified. The indications included post-herpetic neuralgia (PHN) (30.5%), musculoskeletal diseases other than fibromyalgia (21.2%), fibromyalgia (18.4%), diabetic peripheral neuropathic pain (DPNP) (11.7%) and epilepsy (2.9%). Overall, 62.5% and 6.4% of patients achieved a maximum dose of ≥150 and ≥ 300 mg/day, respectively. The median duration of persistent pregabalin use was 28 days (interquartile range 14–118 days). The one-year persistence rate was 12.1%, and the indications associated with the highest and lowest persistence rates were epilepsy (42.4%) and PHN (6.1%), respectively. Male gender (odds ratio [OR] 1.14, 95% confidence interval [CI] 1.09–1.18), older age (OR 1.01 per year, 95% CI 1.01–1.01), indications other than PHN, especially epilepsy (OR 8.04, 95% CI 7.33–8.81, PHN as reference), and a higher initial dose (OR 1.12 per 75 mg, 95% CI = 1.10–1.15) were associated with persistence at one year, whereas the initial concomitant use of antiviral agents decreased the likelihood (OR 0.41, 95% CI 0.35–0.47).

Conclusions

Pregabalin prescriptions for pain disorders were limited to short-term use, which is consistent around the world. However, the average prescribed dose in Taiwan was lower than those in Western countries, and was frequently below the recommended ranges. Potential causes included the duration of natural history of PHN, and off-label prescriptions for pain in acute herpes zoster, rather than PHN, as well as intolerance to the side effects.

Effects of Monopolar Dielectric Radiofrequency Signals on the Symptoms of Fibromyalgia: A Single-Blind Randomized Controlled Trial

Monopolar dielectric radiofrequency (MDR) is a non-invasive treatment for pain based on the local application of electromagnetic signals. The study’s goal was to analyze the effects of MDR on the symptoms of fibromyalgia. For this aim, a randomized controlled trial was conducted on 66 female participants (aged 47 ± 17.7) diagnosed with fibromyalgia. Participants were randomly allocated to either an experimental group (n = 23), which received eight 20-minute sessions of MDR; a sham group, which received the same number of sessions of a sham MDR therapy (n = 22); or a control group (n = 21), which received usual care. The outcome variables included pain measured by the visual analogue scale (VAS), score on the hospital anxiety and depression scale (HADS) and quality of life measured by the combined index of fibromyalgia severity (ICAF). A large effect size was observed for the local pain (R² = 0.46), total ICAF (R² = 0.42) and ICAF physical factor scores (R² = 0.38). Significant mean differences were found for the local pain (p = 0.025) and ICAF physical factor (p = 0.031) scores of the experimental group in comparison with the sham group. No statistically significant differences between groups were found in HADS. In conclusion, MDR is more effective than either sham treatment or usual care in the short-term improvement of pain and the physical wellbeing of participants with fibromyalgia.

Comparison between Acupuncture and Nutraceutical Treatment with Migratens® in Patients with Fibromyalgia Syndrome: A Prospective Randomized Clinical Trial

OBJECTIVES

Fibromyalgia syndrome (FMS) is a chronic clinical condition characterized by pain, fatigue, altered sleep, and cognitive disturbances. The purpose of this study was to compare two alternative treatments (nutraceutical and acupuncture) in FMS patients through a randomized clinical trial.

RESEARCH METHODS

A total of 60 FMS female patients were randomized for treatment with a nutritional combination containing coenzyme Q10, vitamin D, alpha-lipoic acid, magnesium, and tryptophan (Migratens® Group) or acupuncture treatment (Acupuncture Group) performed according the principles of traditional Chinese medicine (TCM), both for 3 months. Changes in pain and in quality of life (QoL) measured with a Fibromyalgia Impact Questionnaire Score-Revised (FIQ-R) and the Fibromyalgia Severity Scale (FSS) were performed at 1, 3, and 6 months after the start of treatments.

RESULTS

A total of 55 patient completed the study (21 in the Migratens® Group and 34 in the Acupuncture Group). Migratens® treatment shows a statistically significant reduction of pain 1 month after the start of therapy (T1, p = 0.025), strengthened after 3 months with maintenance of treatment (p = 0.012). The efficacy in reducing pain was apparent in the Acupuncture Group at all post-treatment determinations and at follow-up (T1 and T2 p = <0.001). Regarding QoL, improvement in FIQ-R and FSS values was revealed in both groups.

CONCLUSION

The nutraceutical approach with Migratens® seems to be an effective option to for patients with FMS. Our experience confirmed also the validity of acupuncture in these patients. Considering the complexity of the management of FMS patients, our results suggest a cyclical and sequential, or even concurrent treatment with different approaches, to improve the efficacy and the compliance of patients to long-term treatment.

Current and Emerging Pharmacotherapy for Fibromyalgia

Introduction. Fibromyalgia syndrome (FMS) is a pain disorder with an estimated prevalence of 1–5%. It is associated with a variety of somatic and psychological disorders. Its exact pathogenesis is still unclear but is involved with neural oversensitization and decreased conditioned pain modulation (CPM), combined with cognitive dysfunction, memory impairment, and altered information processing. Connectivity between brain areas involved in pain processing, alertness, and cognition is increased in the syndrome, making its pharmacologic therapy complex. Only three drugs, pregabalin, duloxetine, and milnacipran are currently FDA-approved for FM treatment, but many other agents have been tested over the years, with varying efficacy. Areas Covered. The purpose of this review is to summarize current clinical experience with different pharmacologic treatments used for fibromyalgia and introduce future perspectives in developing therapies. Expert Opinion. Future insights into the fields of cannabinoid and opioid research, as well as an integrative approach towards the incorporation of genetics and functional imaging combined with additional fields of research relevant towards the study of complex CNS disorders, are likely to lead to new developments of novel tailor-made treatments for FMS patients.

Insomnia Increases Symptom Severity and Health Care Utilization in Patients With Fibromyalgia: A Population-based Study

Supplemental Digital Content is available in the text.

Objective:

This study aimed to determine whether comorbid insomnia is associated with increased use of fibromyalgia-related medications and health resources in fibromyalgia (FM) patients.

Materials and Methods:

We analyzed data retrieved from the Longitudinal Health Insurance Database 2010, which contains claims data of 1 million beneficiaries randomly selected from Taiwan’s National Health Insurance program. Patients treated for FM (n=17,920) on 2 separate visits between 2000 and 2001 were selected and subsequently divided into 2 groups: patients with and without comorbid insomnia (n=5466 and 12,454, respectively). Insomnia was identified through diagnosis on 2 separate visits after the index FM date. FM-related pharmacotherapies and ambulatory care visits were tracked from the index date to the end of 2013.

Results:

Insomnia was associated with increased likelihood of future use of antidepressants (adjusted odds ratio [OR]=3.84, P<0.001), gabapentin (adjusted OR=1.67, P<0.001), pregabalin (adjusted OR=1.79, P=0.046), muscle relaxants (adjusted OR=3.05, P<0.001), and opioids and tramadol (adjusted OR=1.59, P<0.001) among FM patients compared with FM patients without insomnia. In addition, a diagnosis of insomnia was associated with an increased frequency of visits to ambulatory care services for both FM (β=1.79; 95% confidence interval, 1.57-2.02; P<0.001) and other conditions (β=108.51; 95% confidence interval, 103.14-113.89; P<0.001).

Discussion:

This study demonstrates the substantial burden of comorbid insomnia in patients with FM.

An experimental randomized study on the analgesic effects of pharmaceutical-grade cannabis in chronic pain patients with fibromyalgia

Supplemental Digital Content is Available in the Text.

This experimental highly controlled trial in 20 patients with fibromyalgia shows that the cannabinoid THC, but not CBD, is effective in the treatment of fibromyalgia pain.

In this experimental randomized placebo-controlled 4-way crossover trial, we explored the analgesic effects of inhaled pharmaceutical-grade cannabis in 20 chronic pain patients with fibromyalgia. We tested 4 different cannabis varieties with exact knowledge on their ∆⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD) content: Bedrocan (22.4-mg THC, <1-mg CBD; Bedrocan International BV, Veendam, the Netherlands), Bediol (13.4-mg THC, 17.8-mg CBD; Bedrocan International BV, Veendam, the Netherlands), Bedrolite (18.4-mg CBD, <1-mg THC; Bedrocan International BV, Veendam, the Netherlands), and a placebo variety without any THC or CBD. After a single vapor inhalation, THC and CBD plasma concentrations, pressure and electrical pain thresholds, spontaneous pain scores, and drug high were measured for 3 hours. None of the treatments had an effect greater than placebo on spontaneous or electrical pain responses, although more subjects receiving Bediol displayed a 30% decrease in pain scores compared to placebo (90% vs 55% of patients, P = 0.01), with spontaneous pain scores correlating with the magnitude of drug high (ρ = −0.5, P < 0.001). Cannabis varieties containing THC caused a significant increase in pressure pain threshold relative to placebo (P < 0.01). Cannabidiol inhalation increased THC plasma concentrations but diminished THC-induced analgesic effects, indicative of synergistic pharmacokinetic but antagonistic pharmacodynamic interactions of THC and CBD. This experimental trial shows the complex behavior of inhaled cannabinoids in chronic pain patients with just small analgesic responses after a single inhalation. Further studies are needed to determine long-term treatment effects on spontaneous pain scores, THC–CBD interactions, and the role of psychotropic symptoms on pain relief.

Recreational use of GHB is associated with alterations of resting state functional connectivity of the central executive and default mode networks

Gamma-hydroxybutyrate acid (GHB) is a recreational drug with a high addictive potential. Severe side effects such as GHB-induced coma are common and linked to increased emergency room attendances. Task-based functional-imaging studies have revealed an association between the regular use of GHB and multiple GHB-induced comas, and altered neurocognitive function. However the effects of multiple GHB-induced comas and regular GHB-use on intrinsic brain connectivity during rest remain unknown. The study population consisted of 23 GHB-users with ≥4 GHB-induced comas (GHB-Coma), 22 GHB-users who never experienced a GHB-induced coma (GHB-NoComa) and 24 polydrug users who never used GHB (No-GHB). Resting-state scans were collected to assess resting-state functional-connectivity within and between the default mode network (DMN), the bilateral central executive network (CEN) and the salience network (SN). The GHB-NoComa group showed decreased rsFC of the right CEN with a region in the anterior cingulate cortex (pFWE  = 0.048) and decreased rsFC between the right CEN and the DMN (pFWE  = 0.048) when compared with the No-GHB group. These results suggest that regular GHB-use is associated with decreased rsFC within the right CEN and between the right CEN and the DMN. The presence of multiple GHB-induced comas is not associated with (additional) alterations in rsFC.

Strategies to Treat Chronic Pain and Strengthen Impaired Descending Noradrenergic Inhibitory System

Gabapentinoids (gabapentin and pregabalin) and antidepressants (tricyclic antidepressants and serotonin noradrenaline reuptake inhibitors) are often used to treat chronic pain. The descending noradrenergic inhibitory system from the locus coeruleus (LC) to the dorsal horn of the spinal cord plays an important role in the analgesic mechanisms of these drugs. Gabapentinoids activate the LC by inhibiting the release of γ-aminobutyric acid (GABA) and inducing the release of glutamate, thereby increasing noradrenaline levels in the spinal cord. Antidepressants increase noradrenaline levels in the spinal cord by inhibiting reuptake, and accumulating noradrenaline inhibits chronic pain through α₂-adrenergic receptors in the spinal cord. Recent animal studies, however, revealed that the function of the descending noradrenergic inhibitory system is impaired in chronic pain states. Other recent studies found that histone deacetylase inhibitors and antidepressants restore the impaired noradrenergic descending inhibitory system acting on noradrenergic neurons in the LC.

Gabapentin and pregabalin to treat aggressivity in dementia: a systematic review and illustrative case report

AIMS

The prevalence of dementia is rising as life expectancy increases globally. Behavioural and psychological symptoms of dementia (BPSD), including agitation and aggression, are common, presenting a challenge to clinicians and caregivers.

METHODS

Following PRISMA guidelines, we systematically reviewed evidence for gabapentin and pregabalin against BPSD symptoms of agitation or aggression in any dementia, using six databases (Pubmed, CINHL, PsychINFO, HealthStar, Embase, and Web of Science). Complementing this formal systematic review, an illustrative case of a patient with BPSD in mixed Alzheimer's/vascular dementia, who appeared to derive benefits in terms of symptom control and functioning from the introduction of gabapentin titrated up to 3600 mg day^-1 alongside other interventions, is presented.

RESULTS

Twenty-four relevant articles were identified in the systematic review. There were no randomized trials. Fifteen papers were original case series/case reports of patients treated with these compounds, encompassing 87 patients given gabapentin and six given pregabalin. In 12 of 15 papers, drug treatment was effective in the majority of cases. The remaining nine papers were solely reviews, of which two were described as systematic but predated PRISMA guidelines. Preliminary low-grade evidence based on case series and case reviews suggests possible benefit of gabapentin and pregabalin in patients with BPSD in Alzheimer's disease. These benefits cannot be confirmed until well-powered randomized controlled trials are undertaken. Evidence in frontotemporal dementia is lacking.

CONCLUSION

Gabapentin and pregabalin could be considered for BPSD when medications having stronger evidence bases (risperidone, other antipsychotics, carbamazepine and citalopram) have been ineffective or present unacceptable risks of adverse outcomes.

Itch and psyche: psychiatric aspects of pruritus

Itch, also referred to as pruritus, is an unpleasant cutaneous sensation provoking the desire to scratch. It is often an uncomfortable, subjective sensation responsible for decreased quality of life in a variety of psychodermatological conditions. Comorbid psychiatric conditions, including depression and anxiety, are frequently associated with itch and scratch cycle. The reciprocal and intricate relationship between the psyche and itch has been widely studied. The neurobiology of itch involves the complexity of specific mediators, itch-related neuronal pathways, and central processing of itch. The connection between itch and the psyche can be grouped under three headings: pruritic diseases with psychosocial sequelae, pruritic diseases aggravated by psychosocial factors, and psychiatric disorders causing pruritus. Itch and pain modulation go together in most circumstances and involve various substances including histamine, interleukins, protease-activated receptors, transient receptor potential receptors, opioids, and cannabinoids. The close interaction between keratinocytes and nerve endings modulating pain and itch also play a major role. Management of itch associated with its psychosomatic components is directed at an underlying cause and adopting a holistic approach to address not only dermatologic and somatosensory aspects, but also the cognitive, emotional, and psychosocial components. An integrated multidisciplinary team consisting of a dermatologist, psychiatrist, psychologist, and social worker is vital in addressing the multifaceted aspects of pruritus.

Combination pharmacotherapy for the treatment of fibromyalgia in adults

BACKGROUND

Fibromyalgia is a chronic widespread pain condition affecting millions of people worldwide. Current pharmacotherapies are often ineffective and poorly tolerated. Combining different agents could provide superior pain relief and possibly also fewer side effects.

OBJECTIVES

To assess the efficacy, safety, and tolerability of combination pharmacotherapy compared to monotherapy or placebo, or both, for the treatment of fibromyalgia pain in adults.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and Embase to September 2017. We also searched reference lists of other reviews and trials registries.

SELECTION CRITERIA

Double-blind, randomised controlled trials comparing combinations of two or more drugs to placebo or other comparators, or both, for the treatment of fibromyalgia pain.

DATA COLLECTION AND ANALYSIS

From all studies, we extracted data on: participant-reported pain relief of 30% or 50% or greater; patient global impression of clinical change (PGIC) much or very much improved or very much improved; any other pain-related outcome of improvement; withdrawals (lack of efficacy, adverse events), participants experiencing any adverse event, serious adverse events, and specific adverse events (e.g. somnolence and dizziness). The primary comparison was between combination and one or all single-agent comparators. We also assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We identified 16 studies with 1474 participants. Three studies combined a non-steroidal anti-inflammatory drug (NSAID) with a benzodiazepine (306 participants); two combined amitriptyline with fluoxetine (89 participants); two combined amitriptyline with a different agent (92 participants); two combined melatonin with an antidepressant (164 participants); one combined carisoprodol, paracetamol (acetaminophen), and caffeine (58 participants); one combined tramadol and paracetamol (acetaminophen) (315 participants); one combined malic acid and magnesium (24 participants); one combined a monoamine oxidase inhibitor with 5-hydroxytryptophan (200 participants); and one combined pregabalin with duloxetine (41 participants). Six studies compared the combination of multiple agents with each component alone and with inactive placebo; three studies compared combination pharmacotherapy with each individual component but did not include an inactive placebo group; two studies compared the combination of two agents with only one of the agents alone; and three studies compared the combination of two or more agents only with inactive placebo.Heterogeneity among studies in terms of class of agents evaluated, specific combinations used, outcomes reported, and doses given prevented any meta-analysis. None of the combinations of drugs found provided sufficient data for analysis compared with placebo or other comparators for our preferred outcomes. We therefore provide a narrative description of results. There was no or inadequate evidence in any comparison for primary and secondary outcomes. Two studies only reported any primary outcomes of interest (patient-reported pain relief of 30%, or 50%, or greater). For each 'Risk of bias' item, only half or fewer of studies had unequivocal low risk of bias. Small size and selective reporting were common as high risk of bias.Our GRADE assessment was therefore very low for primary outcomes of pain relief of 30% or 50% or greater, PGIC much or very much improved or very much improved, any pain-related outcome, participants experiencing any adverse event, any serious adverse event, or withdrawing because of an adverse event.Three studies found some evidence that combination pharmacotherapy reduced pain compared to monotherapy; these trials tested three different combinations: melatonin and amitriptyline, fluoxetine and amitriptyline, and pregabalin and duloxetine. Adverse events experienced by participants were not serious, and where they were reported (in 12 out of 16 studies), all participants experienced them, regardless of treatment. Common adverse events were nausea, dizziness, somnolence, and headache.

AUTHORS' CONCLUSIONS

There are few, large, high-quality trials comparing combination pharmacotherapy with monotherapy for fibromyalgia, consequently limiting evidence to support or refute the use of combination pharmacotherapy for fibromyalgia.

Analgesic Mechanisms of Antidepressants for Neuropathic Pain

Tricyclic antidepressants and serotonin noradrenaline reuptake inhibitors are used to treat chronic pain, such as neuropathic pain. Why antidepressants are effective for treatment of neuropathic pain and the precise mechanisms underlying their effects, however, remain unclear. The inhibitory effects of these antidepressants for neuropathic pain manifest more quickly than their antidepressive effects, suggesting different modes of action. Recent studies of animal models of neuropathic pain revealed that noradrenaline is extremely important for the inhibition of neuropathic pain. First, increasing noradrenaline in the spinal cord by reuptake inhibition directly inhibits neuropathic pain through α₂-adrenergic receptors. Second, increasing noradrenaline acts on the locus coeruleus and improves the function of an impaired descending noradrenergic inhibitory system. Serotonin and dopamine may reinforce the noradrenergic effects to inhibit neuropathic pain. The mechanisms of neuropathic pain inhibition by antidepressants based mainly on experimental findings from animal models of neuropathic pain are discussed in this review.

Fibromyalgia: Treating Pain in the Juvenile Patient

Presently, evidence for the efficacy of medications for the treatment of juvenile fibromyalgia syndrome (JFMS) is limited. While there are medications approved by the US Food and Drug Administration (duloxetine, milnacipran and pregabalin) for adults with fibromyalgia syndrome, there are none for the treatment of JFMS. A variety of medications have been prescribed for the treatment of JFMS, including (but not limited to) non-opioid analgesics, opioids, anticonvulsants, antidepressants, and muscle relaxants. Psychological therapies, most prominently cognitive behavioral therapy, are the most evidenced-based treatment modalities for JFMS. A multidisciplinary approach, combining pharmacological, behavioral and exercise-based modalities is currently the standard of care for JFMS. In the future, more stringent randomized, controlled trials with longer follow-up periods are needed in order to determine the long-term efficacy and safety of medications in the treatment of JFMS. Additionally, improved recognition of JFMS will allow for better patient recruitment to permit for adequately powered study designs.

Association between fibromyalgia syndrome and peptic ulcer disease development

PURPOSE

The correlation of fibromyalgia syndrome (FMS) with peptic ulcer disease (PUD) is unclear. We therefore conducted a cohort study to investigate whether FMS is correlated with an increased risk of PUD.

METHODS

In this study, we established an FMS cohort comprising 26068 patients aged more than 20 years who were diagnosed with FMS from 2000 to 2011. Furthermore, we established a control cohort by randomly choosing 104269 people without FMS who were matched to the FMS patients by gender, age, and index year. All patients were free of PUD at the baseline. Cox proportional hazard regressions were performed to compute the hazard ratio of PUD after adjustment for demographic characteristics and comorbidities.

RESULTS

The prevalence of comorbidities was significantly higher in the FMS patients than in the controls. The incidence of PUD was 29.8 and 19.4 per 1000 person-years in the FMS and control cohorts, respectively. In addition, the FMS cohort exhibited a 1.40-fold higher risk of PUD (95% confidence interval = 1.35-1.45) compared with the control cohort. After control for confounding factors, the medications (selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and antidepressants) taken by the FMS patients did not increase the risk of PUD.

CONCLUSION

FMS patients exhibit a higher risk of PUD than that of patients without FMS.

Activated Charcoal Haemoperfusion in the Treatment of Experimental Amitriptyline Poisoning in Pigs - The Effect on Amitriptyline Plasma Concentration and Haemodynamic Parameters

Coated activated charcoal haemoperfusion (CAC-HP) is a well-known treatment modality. Case reports have revealed conflicting results about the efficacy of CAC-HP in the treatment of amitriptyline (AT) poisoning, and no randomized clinical trials have been identified in the literature. This study aimed at quantifying the efficacy of modern CAC-HP as an adjunctive treatment of AT intoxication compared with standard care alone. Fourteen female Danish landrace pigs were randomized to either standard care or standard care plus 4 hr of CAC-HP. The pigs were anaesthetized, and vital parameters were continuously recorded. Amitriptyline infusion (7.5 mg/kg) was completed in 20 min. Thirty minutes after AT infusion, activated charcoal was instilled orally in both groups. In the intervention group, CAC-HP was initiated 60 min. after AT infusion. Blood and urine samples were collected as were vital parameters at specific time intervals. The protocol was approved by the Danish Experimental Animal Expectorate and complied with the NIH guide for care and use of laboratory animals. Data were managed according to the ARRIVE guidelines. No statistical significant differences between intervention and control groups were found when analysing for differences in AT levels in plasma at any time-point. Furthermore, significant differences between the control and intervention groups in regard to vital parameters could not be found either. In our animal model, the addition of CAC-HP did not improve the clearance of AT compared with standard treatment alone. We suggest that the effect of modern CAC-HP as a treatment modality in AT-poisoned human patients may be inadequate.