Fibromyalgia and small-fiber polyneuropathy: What's in a name?

Psychoeducation for Fibromyalgia Syndrome: A Systematic Review of Emotional, Clinical and Functional Related-Outcomes

Fibromyalgia Syndrome (FMS) is a chronic condition of widespread pain accompanied by several symptoms such as stiffness, fatigue, sleep problems, depression, anxiety, and cognitive deficits. To date, there is no specific treatment for FMS. The European League Against Rheumatism, and the majority of the international recommendations for managing FMS, has claimed psychoeducational intervention as the first step in FMS treatment for adequate symptoms management. However, scientific studies in this regard are scarce, diverse, and with contradictory findings. Results integration from analogous studies could provide a clear presentation of the real clinical value of psychoeducation in FMS. Therefore, the current systematic review aims at exploring the effect of psychoeducation on emotional, clinical, and functional symptoms of FMS patients and encourages researchers towards psychoeducation's procedure optimization and systematization. The systematic review was conducted according to the guidelines of the Cochrane Collaboration and PRISMA statements. The selected articles were evaluated using the Cochrane risk of bias (ROB) assessment tool. The selected articles were extracted from PubMed, Scopus, and Web of Science databases. The literature search identified 11 studies eligible for the systematic review. The ROB evaluation revealed that 2 of the 11 studies showed a low quality, the other 2 had a moderate quality, and the remaining 7 studies exhibited a high quality. Results showed that psychoeducation is generally included as an important first therapeutic step in multicomponent treatments for FMS. Moreover, psychoeducation generally seems to be quite beneficial in reducing emotional (i.e., number of days feeling emotionally well, general anxiety, depression levels, etc.) and clinical symptoms (levels of fatigue, morning stiffness, pain intensity, etc.), as well as increasing functional status (i.e., general physical function, morning fatigue, stiffness, etc.). Despite that psychoeducation´s clinical benefits are highlighted, there is scarce amount of research on psychoeducation beyond its usefulness as part of multicomponent treatments.

Relationships of autonomic dysfunction with disease severity and neuropathic pain features in fibromyalgia: is it really a sympathetically maintained neuropathic pain?

Background

The pathophysiology of fibromyalgia (FM) involves many mechanisms including central nervous system sensitization theory, autonomic nervous system (ANS) dysfunction, and recently small fiber neuropathy. While the small fiber neuropathy itself can cause ANS dysfunction and neuropathic pain (NP), it is still unknown whether ANS problems have an association with severity of disease and NP in patients with FM. The aim of this study was to evaluate ANS dysfunction in FM patients and to explore possible associations of ANS dysfunction with disease severity and NP.

Methods

Twenty-nine FM patients and 20 healthy controls were included in this cross-sectional study. Participants were tested using sympathetic skin responses (SSR) and R-R interval variation analyses for sympathetic and parasympathetic ANS dysfunction, respectively. Disease severity and somatic symptoms of patients with FM were evaluated using the ACR-2010 scales and Fibromyalgia Impact Questionnaire, and NP symptoms were evaluated using the Pain Detect Questionnaire and Douleur Neuropathique questionnaire.

Results

FM patients were found to have ANS dysfunction characterized by increased sympathetic response and decreased parasympathetic response. SSR amplitudes were found to be correlated with a more severe disease. Although non-significant, NP severity tended to be associated with a decrease in sympathetic and parasympathetic activities.

Conclusions

ANS dysfunction may play a role in the pathophysiology of FM. The trend of decreased ANS functions in FM patients exhibiting NP contradicts the notion that FM is a sympathetically maintained NP and may be explained with small fiber involvement.

Assessing Walking Programs in Fibromyalgia: A Concordance Study between Measures

This study analyzes the degree of agreement between three self-report measures (Walking Behavior, WALK questionnaire and logbooks) assessing adherence to walking programs through reporting their components (minutes, rests, times a week, consecutive weeks) and their concordance with a standard self-report of physical activity (IPAQ-S questionnaire) and an objective, namely number of steps (pedometer), in 275 women with fibromyalgia. Regularized partial correlation networks were selected as the analytic framework. Three network models based on two different times of assessment, namely T1 and T2, including 6 weeks between both, were used. WALK and the logbook were connected with Walking Behavior and also with the IPAQ-S. The logbook was associated with the pedometers (Z-score > 1 in absolute value). When the behavior was assessed specifically and in a detailed manner, participants’ results for the different self-report measures were in agreement. Specific self-report methods provide detailed information that is consistent with validated self-report measures (IPAQ-S) and objective measures (pedometers). The self-report measures that assess the behavioral components of physical activity are useful when studying the implementation of walking as physical exercise.

Implications of Nerve Fiber Density on the Diagnosis and Treatment of Juvenile Fibromyalgia

Juvenile fibromyalgia (JFM) is a condition that presents as chronic widespread musculoskeletal pain and affects children and adolescents. JFM remains a challenging diagnosis, as it is both based on subjective criteria and the pathogenesis is poorly understood. Small fiber neuropathy (SFN) is a distinct condition, which is characterized by pathology of small A-delta and C fibers, and can present similarly to JFM. Small fiber pathology is characterized by reduced intraepidermal nerve fiber density (IENFD) on skin biopsy. Recent studies have found that as many as half of patients with JFM can demonstrate decreased IENFD, in pattern similar to SFN. This phenomenon has been referred to as small fiber pathology. The meaning of these findings was disputed; however, the current consensus remains that fibromyalgia and SFN are distinct conditions. Additionally, among patients with fibromyalgia, there are two phenotypes: those with small fiber pathology and those without. The purpose of this review was to characterize the role assessment of IENFD plays in the clinical context. We conducted a narrative review of pertinent articles pertaining to JFM, SFN and small fiber pathology in fibromyalgia. We concluded that assessment of IENFD should be completed if SFN is suspected either when a patient first presents or in patients who were previously diagnosed with fibromyalgia and SFN is later suspected. Distinguishing between JFM and SFN is important because recommended therapies differ between the two conditions. However, there is no evidence to support the use of skin biopsy to distinguish between the two discussed fibromyalgia phenotypes. More studies are needed to elucidate whether IENFD varies with morbidity and if both fibromyalgia phenotypes vary in their response to different therapeutic regimens.

Spa Therapy for the Treatment of Fibromyalgia: An Open, Randomized Multicenter Trial

Fibromyalgia is a common chronic pain pathology with an incidence of 4.3 per 1,000 person-years. An open, randomized clinical trial of patients with fibromyalgia comparing an immediate vs. delayed 18-day spa therapy in five spa therapy care facilities in France enrolled 220 patients. Randomization was in blocks of four, stratified by center, severity of fibromyalgia and previous spa therapy. Patients continued usual treatment. The main endpoint was the number of patients achieving minimal clinically important difference at 6 months, defined as 14% change in their baseline fibromyalgia impact questionnaire score. The intention-to-treat analysis included 100 and 106 patients in the intervention and control groups, respectively. At 6 months, 45/100 (45.0%) and 30/106 (28.3%) patients in the intervention and control groups, respectively, achieved a minimal clinically important difference (P= .013). There was also a significant improvement in pain, fatigue, and symptom severity (secondary outcomes) in the intervention group but not for generic quality of life (QOL), sleep or physical activity. None of the 33 serious adverse events reported by 25 patients were related to the spa therapy. Our results demonstrate the benefit of spa treatment in patients with fibromyalgia. PERSPECTIVE: A 12-month, open, randomized clinical trial of 220 patients with fibromyalgia compared an immediate versus delayed (ie, after 6 months) 18-day spa therapy. The results showed a clinically significant improvement at 6 months for those who received immediate therapy which was maintained up to 12 months. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov: NCT02265029.

High Prevalence of Perineural Cysts in Patients with Fibromyalgia and Chronic Fatigue Syndrome

OBJECTIVE

Pain in fibromyalgia (FM) and chronic fatigue syndrome (CFS) is assumed to originate from central sensitization. Perineural cysts or Tarlov cysts (TCs) are nerve root dilations resulting from pathologically increased cerebrospinal fluid pressure. These cysts initially affect sensory neurons and axons in dorsal root ganglia and produce sensory symptoms (pain and paresthesia). Symptomatic TC (STC) patients often complain about widespread pain and fatigue. Consequently, STC patients may initially be diagnosed with FM, CFS, or both. The objective of this study was to document the prevalence of TCs in patients diagnosed with FM or CFS.

DESIGN

A retrospective study.

SETTING

An outpatient clinic for musculoskeletal disorders.

SUBJECTS

Patients diagnosed with FM according to the 1990 American College of Rheumatology criteria or with CFS according to the 1994 Centers for Disease Control criteria were selected.

METHODS

Review of lumbar and sacral magnetic resonance imaging scans including TCs ≥5 mm in size.

RESULTS

In total, 197 patients with FM, CFS, or both underwent magnetic resonance imaging. Ninety-one percent were women. The mean age was 48.1 (±11.9) years. TCs were observed in 39% of patients, with a mean size of 11.8 (±5.2) mm. In males, the prevalence was 12%, vs. 42% in females.

CONCLUSIONS

In patients diagnosed with FM or CFS, the prevalence of TCs was three times higher than that in the general population. This observation supports the hypothesis that STCs, FM, and CFS may share the same pathophysiological mechanism, i.e., moderately increased cerebrospinal fluid pressure, causing irritation of neurons and axons in dorsal root ganglia.

Reduced activity, reactivity and functionality of the sympathetic nervous system in fibromyalgia: An electrodermal study

Alterations in autonomic activity are well established in fibromyalgia syndrome (FMS). Previous studies found reduced parasympathetic activity and sympathetic reactivity to physical and stress manipulations. However, sympathetic activity at rest has not been well studied in FMS. Sweating is exclusively controlled by sympathetic mechanisms. In this study, skin conductance (SC), as an indirect measure of sweating, was analyzed in 45 women with FMS and 38 healthy women. Tonic SC levels were recorded during a 4-minute rest period, and a breathing maneuver consisting of deep breathing with posterior breath holding was used to evoke SC responses. Associations of tonic SC with state anxiety and body temperature, measured in the hand, were explored to determine sweat functionality. The results showed reduced tonic SC levels, with a less marked decrease in SC during the recording period, and blunted SC reactivity to the breathing manipulation in FMS patients relative to healthy participants. Positive associations of SC with state anxiety and body temperature were observed in healthy participants, but these associations were absent in FMS patients. These results indicate alterations of sweating in FMS, suggesting reduced tonic and reactivity sympathetic influences. Furthermore, the absence of associations between SC levels and state anxiety and body temperature in the patient sample suggested a loss of functionality of the autonomic nervous system in FMS. Diminished autonomic regulation in FMS would reduce the ability to cope with environmental demands, thus favoring increases in stress and pain levels. Finally, the observed reduction in sweating is in accordance with evidence of small nerve fiber neuropathy in FMS.

Combined cognitive-behavioral therapy for fibromyalgia: Effects on polysomnographic parameters and perceived sleep quality

Background/Objective: Cognitive-behavioral therapy (CBT) is one of the first-line treatments in the management of fibromyalgia (FM) and it has been applied with considerable success to treat the psychological processes associated with pain and insomnia. We hypothesized that treating sleep and pain jointly with new combined modalities of CBT may offer greater sleep-related benefits to patients. Method: Thirty-nine female patients with FM and insomnia were randomly allocated to receive CBT centered on pain (CBT-P) or combined CBT focused on pain and insomnia (CBT-C). Participants were assessed at baseline and post-treatment with the Pittsburgh Sleep Quality Index and an ambulatory polysomnography.Results: Participants who received CBT-P showed increases in time in bed and total sleep time and decreases in light sleep, but there was no improvement in perceived sleep quality. Participants who received combined CBT-C showed more meaningful improvements related to refreshing sleep (i.e., higher sleep efficiency and less time awake and longer time in Stage 4 sleep), and these changes were concordant with a significant improvement in self-perceived sleep quality. Conclusions: This study suggests that new CBT-C approaches can improve insomnia-related clinical aspects.

Diagnostic Criteria for Fibromyalgia: Critical Review and Future Perspectives

Fibromyalgia syndrome (FMS) is a chronic illness characterized by widespread pain and other clinical and emotional symptoms. The lack of objective markers of the illness has been a persistent problem in FMS research, clinical management, and social recognition of the disease. A critical historical revision of diagnostic criteria for FMS, especially those formulated by the American College of Rheumatology (ACR), was performed. This narrative review has been structured as follows: Introduction; historical background of FMS, including studies proposing and revising the diagnostic criteria; the process of development of the ACR FMS diagnostic criteria (1990 and 2010 versions); revisions of the 2010 ACR FMS diagnostic criteria; the development of scales based on the 2010 and 2011 criteria, which could help with diagnosis and evaluation of the clinical severity of the disease, such as the Polysymptomatic Distress Scale and the FMS Survey Questionnaire; relationships of prevalence and sex ratio with the different diagnostic criteria; validity and diagnostic accuracy of the ACR FMS criteria; the issues of differential diagnosis and comorbidity; the strength and main limitations of the ACR FMS criteria; new perspectives regarding FMS diagnosis; and the impact of the novel findings in the diagnosis of FMS. It is concluded that despite the official 2010 FMS diagnostic criteria and the diagnostic proposal of 2011 and 2016, complaints from health professionals and patients continue.

Diagnosis and management of sensory polyneuropathy

Sensory polyneuropathies, which are caused by dysfunction of peripheral sensory nerve fibers, are a heterogeneous group of disorders that range from the common diabetic neuropathy to the rare sensory neuronopathies. The presenting symptoms, acuity, time course, severity, and subsequent morbidity vary and depend on the type of fiber that is affected and the underlying cause. Damage to small thinly myelinated and unmyelinated nerve fibers results in neuropathic pain, whereas damage to large myelinated sensory afferents results in proprioceptive deficits and ataxia. The causes of these disorders are diverse and include metabolic, toxic, infectious, inflammatory, autoimmune, and genetic conditions. Idiopathic sensory polyneuropathies are common although they should be considered a diagnosis of exclusion. The diagnostic evaluation involves electrophysiologic testing including nerve conduction studies, histopathologic analysis of nerve tissue, serum studies, and sometimes autonomic testing and cerebrospinal fluid analysis. The treatment of these diseases depends on the underlying cause and may include immunotherapy, mitigation of risk factors, symptomatic treatment, and gene therapy, such as the recently developed RNA interference and antisense oligonucleotide therapies for transthyretin familial amyloid polyneuropathy. Many of these disorders have no directed treatment, in which case management remains symptomatic and supportive. More research is needed into the underlying pathophysiology of nerve damage in these polyneuropathies to guide advances in treatment.

Psychological impact of fibromyalgia: current perspectives

Fibromyalgia syndrome (FMS) is a chronic disorder characterized by widespread and persistent musculoskeletal pain and other frequent symptoms such as fatigue, insomnia, morning stiffness, cognitive impairment, depression, and anxiety. FMS is also accompanied by different comorbidities like irritable bowel syndrome and chronic fatigue syndrome. Although some factors like negative events, stressful environments, or physical/emotional traumas may act as predisposing conditions, the etiology of FMS remains unknown. There is evidence of a high prevalence of psychiatric comorbidities in FMS (especially depression, anxiety, borderline personality, obsessive-compulsive personality, and post-traumatic stress disorder), which are associated with a worse clinical profile. There is also evidence of high levels of negative affect, neuroticism, perfectionism, stress, anger, and alexithymia in FMS patients. High harm avoidance together with high self-transcendence, low cooperativeness, and low self-directedness have been reported as temperament and character features in FMS patients, respectively. Additionally, FMS patients tend to have a negative self-image and body image perception, as well as low self-esteem and perceived self-efficacy. FMS reduces functioning in physical, psychological, and social spheres, and also has a negative impact on cognitive performance, personal relationships (including sexuality and parenting), work, and activities of daily life. In some cases, FMS patients show suicidal ideation, suicide attempts, and consummated suicide. FMS patients perceive the illness as a stigmatized and invisible disorder, and this negative perception hinders their ability to adapt to the disease. Psychological interventions may constitute a beneficial complement to pharmacological treatments in order to improve clinical symptoms and reduce the impact of FMS on health-related quality of life.

The link between idiopathic intracranial hypertension, fibromyalgia, and chronic fatigue syndrome: exploration of a shared pathophysiology

PURPOSE

Idiopathic intracranial hypertension (IICH) is a condition characterized by raised intracranial pressure (ICP), and its diagnosis is established when the opening pressure measured during a lumbar puncture is elevated >20 cm H2O in nonobese patients or >25 cm H2O in obese patients. Papilledema is caused by forced filling of the optic nerve sheath with cerebrospinal fluid (CSF). Other common but underappreciated symptoms of IICH are neck pain, back pain, and radicular pain in the arms and legs resulting from associated increased spinal pressure and forced filling of the spinal nerves with CSF. Widespread pain and also several other characteristics of IICH share notable similarities with characteristics of fibromyalgia (FM) and chronic fatigue syndrome (CFS), two overlapping chronic pain conditions. The aim of this review was to compare literature data regarding the characteristics of IICH, FM, and CFS and to link the shared data to an apparent underlying physiopathology, that is, increased ICP.

METHODS

Data in the literature regarding these three conditions were compared and linked to the hypothesis of the shared underlying physiopathology of increased cerebrospinal pressure.

RESULTS

The shared characteristics of IICH, FM, and CFS that can be caused by increased ICP include headaches, fatigue, cognitive impairment, loss of gray matter, involvement of cranial nerves, and overload of the lymphatic olfactory pathway. Increased pressure in the spinal canal and in peripheral nerve root sheaths causes widespread pain, weakness in the arms and legs, walking difficulties (ataxia), and bladder, bowel, and sphincter symptoms. Additionally, IICH, FM, and CFS are frequently associated with sympathetic overactivity symptoms and obesity. These conditions share a strong female predominance and are frequently associated with Ehlers-Danlos syndrome.

CONCLUSION

IICH, FM, and CFS share a large variety of symptoms that might all be explained by the same pathophysiology of increased cerebrospinal pressure.