Skeletal muscle abnormalities in patients with fibromyalgia

The Pain Outcomes Comparing Yoga vs. Structured Exercise (POYSE) Trial in Veterans With Fibromyalgia: Study Design and Methods

Background

Fibromyalgia is a common pain condition that often leads to significant disability. Unfortunately, the effectiveness of most medications for fibromyalgia is limited, and there is a need for alternative, non-pharmacological therapies. Yoga and aerobic exercise are both evidence-based non-pharmacological treatments for fibromyalgia. However, no prior studies have directly compared the effectiveness of yoga vs. exercise.

Objective

This article describes the study design and recruitment outcomes of the Pain Outcomes comparing Yoga vs. Structured Exercise (POYSE) Trial, a two-arm randomized comparative effectiveness trial.

Methods

Veterans with fibromyalgia, defined by the 2010 American College of Rheumatology diagnostic criteria, who also experienced at least moderate pain severity were enrolled. The participants were randomized to a 12-week yoga-based or a structured exercise program (SEP) and will undergo comprehensive outcome assessments at baseline, 1, 3, 6, and 9 months by interviewers blinded to treatment assignment. The primary outcome will be the overall severity of fibromyalgia as measured by the total Fibromyalgia Impact Questionnaire-Revised. Secondary outcomes included depression, anxiety, health-related quality of life, pain beliefs, fatigue, sleep, and self-efficacy.

Results

A total of 2,671 recruitment letters were sent to potential participants with fibromyalgia. Of the potential participants, 623 (23.3%) were able to be contacted by telephone and had their eligibility assessed. Three hundred seventy-one of those interviewed were found to be eligible (59.6%) and 256 (69.0%) agreed to participate and were randomized to the YOGA (n = 129) or the SEP (n = 127) arm of the trial.

Conclusions

Clinicians are faced with numerous challenges in treating patients with fibromyalgia. The interventions being tested in the POYSE trial have the potential to provide primary care and other care settings with new treatment options for clinicians while simultaneously providing a much needed relief for patients suffering from fibromyalgia.

Trial Registration

Funded by VA Rehabilitation Research and Development (D1100-R); Trial registration: ClinicalTrials.gov, NCT01797263.

The association between overactive bladder and fibromyalgia: A systematic review and meta-analysis

BACKGROUND

Overactive bladder is a common syndrome that significantly affects the quality of life. Fibromyalgia is characterized by widespread pain, impacting patients' lives. The exact mechanisms of the two syndromes remain unknown, but there is an overlap between the suspected pathophysiologies.

OBJECTIVE

To present an overview of the current research on the association between overactive bladder (OAB) and fibromyalgia.

SEARCH STRATEGY

A systematic search of four electronic databases was conducted.

SEARCH STRATEGY

Studies examining the correlation between OAB and fibromyalgia with female patients aged over 18 years were included.

DATA COLLECTION AND ANALYSIS

Two reviewers screened the studies for eligibility. Eligible studies were screened for quality. A meta-analysis was performed for eligible studies.

MAIN RESULTS

Seven studies were included in the final review, of which six presented a positive association between the syndromes. The studies demonstrated a positive association between fibromyalgia and the severity of OAB and an adverse effect on the quality of life related to OAB. A mean effect size of 1.96 (95% confidence interval 0.85-3.06) was calculated.

CONCLUSION

OAB and fibromyalgia are both complex and multifactorial syndromes. The study presents an association between them, but additional studies on the topic should be conducted for a more precise conclusion.

Genome-wide association study identifies RNF123 locus as associated with chronic widespread musculoskeletal pain

Background and objectives

Chronic widespread musculoskeletal pain (CWP) is a symptom of fibromyalgia and a complex trait with poorly understood pathogenesis. CWP is heritable (48%–54%), but its genetic architecture is unknown and candidate gene studies have produced inconsistent results. We conducted a genome-wide association study to get insight into the genetic background of CWP.

Methods

Northern Europeans from UK Biobank comprising 6914 cases reporting pain all over the body lasting >3 months and 242 929 controls were studied. Replication of three independent genome-wide significant single nucleotide polymorphisms was attempted in six independent European cohorts (n=43 080; cases=14 177). Genetic correlations with risk factors, tissue specificity and colocalisation were examined.

Results

Three genome-wide significant loci were identified (rs1491985, rs10490825, rs165599) residing within the genes Ring Finger Protein 123 (RNF123), ATPase secretory pathway Ca²⁺transporting 1 (ATP2C1) and catechol-O-methyltransferase (COMT). The RNF123 locus was replicated (meta-analysis p=0.0002), the ATP2C1 locus showed suggestive association (p=0.0227) and the COMT locus was not replicated. Partial genetic correlation between CWP and depressive symptoms, body mass index, age of first birth and years of schooling were identified. Tissue specificity and colocalisation analysis highlight the relevance of skeletal muscle in CWP.

Conclusions

We report a novel association of RNF123 locus and a suggestive association of ATP2C1 locus with CWP. Both loci are consistent with a role of calcium regulation in CWP. The association with COMT, one of the most studied genes in chronic pain field, was not confirmed in the replication analysis.

The Search for Biomarkers in Fibromyalgia

Fibromyalgia is the most common of the central sensitivity syndromes affecting 2–5% of the adult population in the United States. This pain amplification syndrome has enormous societal impact as measured by work absenteeism, decreased work productivity, disability and injury compensation and over-utilization of healthcare resources. Multiple studies have shown that early diagnosis of this condition can improve patient outlook and redirect valuable healthcare resources towards more appropriate targeted therapy. Efforts have been made towards improving diagnostic accuracy through updated criteria. The search for biomarkers for diagnosis and verification of Fibromyalgia is an ongoing process. Inadequacies with current diagnostic criteria for this condition have fueled these efforts for identification of a reproducible marker that can verify this disease in a highly sensitive, specific and reproducible manner. This review focuses on areas of research for biomarkers in fibromyalgia and suggests that future efforts might benefit from approaches that utilize arrays of biomarkers to identify this disorder that presents with a diverse clinical phenotype.

EEG biofeedback treatment improves certain attention and somatic symptoms in fibromyalgia: a pilot study

Fibromyalgia (FMS) is a chronic, painful disorder often associated with measurable deficiencies in attention. Since EEG biofeedback (EEG-BF) has been used successfully to treat attention problems, we reasoned that this modality might be helpful in the treatment of attention problems in FMS. We also speculated that improvement in central nervous system (CNS) function might be accompanied by improvement in FMS somatic symptoms. We studied fifteen FMS patients with attention problems, demonstrated by visual and auditory continuous performance testing (CPT), while completing 40 or more EEG-BF sessions. Training consisted of a "SMR protocol" that augmented 12-15 Hz brainwaves (sensory motor rhythm; SMR), while simultaneously inhibiting 4-7 Hz brainwaves (theta) and 22-30 Hz brainwaves (high beta). Serial measurements of pain, fatigue, psychological distress, morning stiffness, and tenderness were also obtained. Sixty-three FMS patients who received standard medical care, but who did not receive EEG-BF, served as controls. Visual, but not auditory, attention improved significantly (P < 0.008). EEG-BF treated subjects also showed improvement in tenderness, pain and fatigue. Somatic symptoms did not change significantly in controls. Visual attention parameters and certain somatic features of FMS appear to improve with an EEG-BF SMR protocol. EEG-BF training in FMS deserves further study.

ATP, calcium and magnesium levels in platelets of patients with primary fibromyalgia

OBJECTIVES

To evaluate the intracellular levels of the high energy adenosine triphosphate nucleotide ATP and essential divalent cations, calcium and magnesium, in platelets of patients affected by primary fibromyalgia syndrome (FMs).

DESIGN AND METHOD

Platelet ATP and cation concentrations were measured in 25 patients affected by FMs and 25 healthy volunteers through a chemiluminescent and a fluorimetric assay, respectively.

RESULTS

Significant lower ATP levels were observed inside platelets of FM patients (fmol ATP/plt: 0.0169+/-0.0012 vs. healthy controls, fmol ATP/plt: 0.0306+/-0.0023, mean+/-SEM) (*** P<0.0001). A trend towards higher calcium concentrations (P=0.06) together with significant increased magnesium levels were also reported in platelets of patients by comparison with controls (P=0.02).

CONCLUSIONS

This preliminary study suggests that disturbances in the homeostasis of platelet ATP metabolism-signaling and calcium-magnesium flows might have a relevance in the pathogenesis of FMs.

Antidepressants in the treatment of fibromyalgia

Fibromyalgia syndrome is a chronic disease of widespread and debilitating pain whose cause is unknown and whose risk factors are poorly understood. It is often comorbid with rheumatoid and other pain disorders as well as psychiatric disorders such as anxiety and depression. Although they are not officially approved for this indication, antiepileptics and antidepressants are often used to treat fibromyalgia. The tricyclic antidepressants (TCAs), particularly amitriptyline, are among the most common treatment strategies. Because of the poor tolerability of the tricyclics, the newer antidepressants have been widely tested in fibromyalgia. The selective serotonin reuptake inhibitors (SSRIs) and the reversible monoamine oxidase inhibitors do not seem to be particularly helpful. The serotonin and norepinephrine reuptake inhibitors (SNRIs), duloxetine and milnacipran, on the other hand, have been shown in placebo-controlled trials to offer significant relief to patients suffering from fibromyalgia. Although no direct comparative studies have been performed, these compounds appear to be as effective as the TCAs but much better tolerated. The effectiveness of the SNRIs as well as other dual acting antidepressants, such as mirtazapine, but not the SSRIs, implies that a dysfunction of both serotonin and norepinephrine neurotransmission probably exists in fibromyalgia. The effectiveness of antidepressants appears to be independent of their effect on comorbid depression.

Current concepts in the pathophysiology of fibromyalgia: the potential role of oxidative stress and nitric oxide

Fibromyalgia (FM) is a common chronic pain syndrome with an unknown etiology. Recent years added new information to our understanding of FM pathophysiology. Researches on genetics, biogenic amines, neurotransmitters, hypothalamic-pituitary-adrenal axis hormones, oxidative stress, and mechanisms of pain modulation, central sensitization, and autonomic functions in FM revealed various abnormalities indicating that multiple factors and mechanisms are involved in the pathogenesis of FM. Oxidative stress and nitric oxide may play an important role in FM pathophysiology, however it is still not clear whether oxidative stress abnormalities documented in FM are the cause or the effect. This should encourage further researches evaluating the potential role of oxidative stress and nitric oxide in the pathophysiology of FM and the efficacy of antioxidant treatments (omega-3 and -6 fatty acids, vitamins and others) in double blind and placebo controlled trials. These future researches will enhance our understanding of the complex pathophysiology of this disorder.

Is fibromyalgia a muscle disorder?

The presence of abnormalities in fibromyalgia muscle using current methodological approaches is well established. The more serious abnormalities are demonstrated by histologic studies particularly on electron microscopy: disorganisation of Z bands and abnormalities in the number and shape of mitochondria. Biochemical studies and P 31 magnetic resonance spectroscopy show inconstant abnormalities of ATP and phosphocreatine levels. Mitochondrial abnormalities reduced capillary circulation and thickened capillary endothelium may result in decreased availability of oxygen and impaired oxidative phosphorylation as well as ATP synthesis. These abnormalities do not seem to be the consequences of the much-discussed deconditioning of muscles although these consequences are not well known. Further studies of energy metabolism of the muscle during exercise are needed.

Benefit of Ribose in a Patient with Fibromyalgia

Ribose was added to the existing treatment regimen of a woman with fibromyalgia, resulting in a decrease in symptoms. It has been postulated that patients with fibromyalgia may have an alteration in muscle adenine nucleotide metabolism, leading to depleted energy reserves and an imbalance in cellular adenosine 5'-triphosphate:adenosine 5'-diphosphate:adenosine 5'-monophosphate (ATP:ADP:AMP) ratios with an abnormal energy charge. As a key component in adenine nucleotide synthesis, ribose supplementation may be useful in such patients.

Childhood adversities in patients with fibromyalgia and somatoform pain disorder

Primary fibromyalgia is regarded as disorder with a complex symptomatology, and no morphological alterations. Findings increasingly point to a dysfunction of the central nervous pain processing. The study aims to discuss vulnerability for fibromyalgia from a developmental psychopathological perspective. We investigated the presence of psychosocial adversities affecting the childhood of adult fibromyalgia patients (FM) and compared them to those of patients with somatoform pain disorders (SOM) and a control group (CG) with medically explained chronic pain. Using the structured biographical interview for pain patients (SBI-P), 38 FM patients, 71 SOM patients, and 44 CG patients were compared on the basis of 14 childhood adversities verified as relevant regarding longterm effects for adult health by prospective studies. The FM patients show the highest score of childhood adversities. In addition to sexual and physical maltreatment, the FM patients more frequently reported a poor emotional relationship with both parents, a lack of physical affection, experiences of the parents' physical quarrels, as well as alcohol or other problems of addiction in the mother, separation, and a poor financial situation before the age of 7. These experiences were found to a similar extent in the SOM patients, but distinctly less frequently in the CG. The results point to early psychosocial adversities as holding a similar etiological meaning in fibromyalgia as well as in somatoform pain disorders. The potential role of these factors as increasing the vulnerability for fibromyalgia is discussed.

The neuropharmacology of centrally-acting analgesic medications in fibromyalgia

As demonstrated above, the anatomy and neuropharmacology of the pain pathways within the CNS, even to the level of the midbrain, are extraordinarily complex. Indeed, discussions of the effects of these agents on the neuropharmacology of the thalamus, hypothalamus, and cortex were excluded from this review owing to their adding further to this complexity. Also, the dearth of data regarding FMS pain pathophysiology necessitated a relatively generic analysis of the pain pathways. As mentioned in the introduction, the current thought is that central sensitization plays an important role in FMS. However, we see in this chapter that the behavioral state of central sensitization may be a result of alterations in either the ascending systems or in one or more descending systems. Studies to assess the presence or relative importance of such changes in FMS are difficult to perform in humans, and to date there are no animal models of FMS. Accepting these limitations, it is apparent that many drugs considered to date for the treatment of FMS do target a number of appropriate sites within both the ascending and descending pain pathways. The data regarding clinical efficacy on some good candidate agents, however, is extremely preliminary. For example, it is evident from the present analysis that SNRIs, alpha 2 agonists, and NK1 antagonists may be particularly well suited to FMS, although current data supporting their use is either anecdotal or from open-label trials [114,149]. Other sites within the pain pathways have not yet been targeted. Examples of these include the use of CCKB antagonists to block on-cell activation or of nitric oxide synthetase antagonists to block the downstream mediators of NMDA activation. Efficacy of such agents may give considerable insight into the pathophysiology of FMS. Finally, as indicated previously, FMS consists of more than just chronic pain, and the question of how sleep abnormalities, depression, fatigues, and so forth tie into disordered pain processing is being researched actively. Future research focusing on how the various manifestations of FMS relate to one another undoubtedly will lead to a more rational targeting of drugs in this complex disorder.

Muscle performance in patients with fibromyalgia

OBJECTIVES

To compare muscle performance in women with fibromyalgia and in healthy women.

PATIENTS AND METHODS

Sixteen women with fibromyalgia syndrome (FMS) and 85 healthy women who were physically inactive or engaged in recreational sports underwent measurements of four parameters: maximal concentric isokinetic muscle strength of the knee extensors and flexors in the dominant limb, isometric grip strength on a Colin dynamometer, muscle fatigue resistance during 30 maximal concentric isokinetic contractions of the dominant knee flexors and extensors at 180 degrees angular velocity, and static endurance during posture maintenance.

RESULTS

All muscle variables were decreased in the FMS patients as compared to the controls. The decreases were more marked during aerobic than during anaerobic exercise. Mean decreases were 39% (P<0.001) for muscle strength, 40% (P<0.0001) for fatigue resistance, and 81% (P<0.0001) for static endurance. Pain during exercise as evaluated using a visual analog scale was more marked in the FMS patients.

CONCLUSION

This study of the three pathways supplying energy to muscle confirms that muscle function is globally impaired in FMS patients. The results suggest that the impairment predominates on aerobic processes.

Prescribing exercise for people with fibromyalgia

Fibromyalgia (FM) is a costly and debilitating pain syndrome which is commonly encountered by advanced practice nurses working in acute care settings. Fibromyalgia affects nearly 6 million people in the United States, approximately 80% to 90% of whom are women. Symptoms of FM include widespread and localized pain, disrupted sleep, fatigue, visceral pain and other pain syndromes, neurological symptoms (eg, dizziness, numbness, tingling, impaired cognition), and exercise-induced pain. Difficulties remaining active with FM may lead to extreme deconditioning, inability to remain employed, and eventually even impaired ability in complete activities of daily living. Exercise that combats deconditioning without triggering pain is, therefore, a key component in treating FM. Clinicians who understand FM pain and associated symptoms can minimize the negative impact of deconditioning by prescribing disease-specific exercise for people with FM.

[What happens to the fibromyalgia syndrome?]

OBJECTIVE

To realize a clarification about fibromyalgia, attempting to consider diagnostic criteria, prevalence, pathophysiology and therapeutic approach.

METHOD

A systematic literature search was conducted to select articles about fibromyalgia and connected diseases. The database are Premedline, Medline and Medlineplus.

RESULTS

Fifty-eight articles about fibromyalgia and twelve articles about connected diseases were selected to realize this review of literature.

DISCUSSION

Fibromyalgia constitutes a syndrome characterized by widespread musculo-skeletal pain, present above the waist and below the waist and in the axial skeleton. Widespread pain must have been present for at least three months. "Spasmophilie", chronic fatigue syndrome and myofascial syndrome represent diseases connected with fibromyalgia: differential diagnosis must be established. Researches related to fibromyalgia suggest a reduction of muscular performances associated with histological and biochemical anomalies. Patients are characterized by shorter and nonrestorative sleep. Psychological, neuroendocrine and central alterations appear often associated with fibromyalgia. The reduction of pressure tolerance and pain thresholds may be linked to the alterations of neuroendocrine substances. Literature recommend a multidisciplinary therapeutic approach in management of fibromyalgia.

CONCLUSION

The pathophysiologic mechanisms in fibromyalgia appear multiple and interdependent. With the aim to optimizing treatment, investigations are necessary to determine biochemical repercussions of various therapeutic approaches.

Static magnetic fields for treatment of fibromyalgia: a randomized controlled trial

OBJECTIVE

To test effectiveness of static magnetic fields of two different configurations, produced by magnetic sleep pads, as adjunctive therapies in decreasing patient pain perception and improving functional status in individuals with fibromyalgia.

DESIGN

Randomized, placebo-controlled, 6-month trial conducted from November 1997 through December 1998.

SETTING AND SUBJECTS

Adults who met the 1990 American College of Rheumatology criteria for fibromyalgia were recruited through clinical referral and media announcements and evaluated at a university-based clinic.

INTERVENTIONS

Subjects in Functional Pad A group used a pad for 6 months that provided whole-body exposure to a low, uniform static magnetic field of negative polarity. Subjects in the Functional Pad B group used a pad for 6 months that exposed them to a low static magnetic field that varied spatially and in polarity. Subjects in two Sham groups used pads that were identical in appearance and texture to the functional pads but contained inactive magnets; these groups were combined for analysis. Subjects in the Usual Care group continued with their established treatment regimens.

OUTCOME MEASURES

Primary outcomes were the change scores at 6 months in the following measures: functional status (Fibromyalgia Impact Questionnaire), pain intensity ratings, tender point count, and a tender point pain intensity score.

RESULTS

There was a significant difference among groups in pain intensity ratings (p = 0.03), with Functional Pad A group showing the greatest reduction from baseline at 6 months. All four groups showed a decline in number of tender points, but differences among the groups were not significant (p = 0.72). The functional pad groups showed the largest decline in total tender point pain intensity, but overall differences were not significant (p = 0.25). Improvement in functional status was greatest in the functional pad groups, but differences among groups were not significant (p = 0.23).

CONCLUSIONS

Although the functional pad groups showed improvements in functional status, pain intensity level, tender point count, and tender point intensity after 6 months of treatment, with the exception of pain intensity level these improvements did not differ significantly from changes in the Sham group or in the Usual Care group.