Fibromyalgia

The dose-dependent effects of transcutaneous electrical nerve stimulation for pain relief in individuals with fibromyalgia: a systematic review and meta-analysis

ABSTRACT

Transcutaneous electrical nerve stimulation (TENS) is a nonpharmacological modality widely used to manage pain; however, its effectiveness for individuals with fibromyalgia (FM) has been questioned. In previous studies and systematic reviews, variables related to dose of TENS application have not been considered. The objectives of this meta-analysis were (1) to determine the effect of TENS on pain in individuals with FM and (2) determine the dose-dependent effect of TENS dose parameters on pain relief in individuals with FM. We searched the PubMed, PEDro, Cochrane, and EMBASE databases for relevant manuscripts. Data were extracted from 11 of the 1575 studies. The quality of the studies was assessed using the PEDro scale and RoB-2 assessment. This meta-analysis was performed using a random-effects model that, when not considering the TENS dosage applied, showed that the treatment had no overall effect on pain (d+ = 0.51, P > 0.050, k = 14). However, the moderator analyses, which were performed assuming a mixed-effect model, revealed that 3 of the categorical variables were significantly associated with effect sizes: the number of sessions (P = 0.005), the frequency (P = 0.014), and the intensity (P = 0.047). The electrode placement was not significantly associated with any effect sizes. Thus, there is evidence that TENS can effectively reduce pain in individuals with FM when applied at high or at mixed frequencies, a high intensity, or in long-term interventions involving 10 or more sessions. This review protocol was registered at PROSPERO (CRD42021252113).

The Troublesome Ticks Research Protocol: Developing a Comprehensive, Multidiscipline Research Plan for Investigating Human Tick-Associated Disease in Australia

In Australia, there is a paucity of data about the extent and impact of zoonotic tick-related illnesses. Even less is understood about a multifaceted illness referred to as Debilitating Symptom Complexes Attributed to Ticks (DSCATT). Here, we describe a research plan for investigating the aetiology, pathophysiology, and clinical outcomes of human tick-associated disease in Australia. Our approach focuses on the transmission of potential pathogens and the immunological responses of the patient after a tick bite. The protocol is strengthened by prospective data collection, the recruitment of two external matched control groups, and sophisticated integrative data analysis which, collectively, will allow the robust demonstration of associations between a tick bite and the development of clinical and pathological abnormalities. Various laboratory analyses are performed including metagenomics to investigate the potential transmission of bacteria, protozoa and/or viruses during tick bite. In addition, multi-omics technology is applied to investigate links between host immune responses and potential infectious and non-infectious disease causations. Psychometric profiling is also used to investigate whether psychological attributes influence symptom development. This research will fill important knowledge gaps about tick-borne diseases. Ultimately, we hope the results will promote improved diagnostic outcomes, and inform the safe management and treatment of patients bitten by ticks in Australia.

The Influence of Opioids on Transcutaneous Electrical Nerve Stimulation Effects in Women With Fibromyalgia

Transcutaneous electrical nerve stimulation (TENS) uses endogenous opioids to produce analgesia, and effectiveness can be reduced in opioid-tolerant individuals'. We examined TENS effectiveness (primary aim), and differences in fibromyalgia symptoms (secondary aim), in women with fibromyalgia regularly taking opioid (RTO) medications compared with women not- regularly taking opioids (not-RTO). Women (RTO n = 79; not-RTO not-n = 222) with fibromyalgia with daily pain levels ≥4 were enrolled and categorized into RTO (taking opioids at least 5 of 7 days in last 30 days) or not-RTO groups. Participants were categorized into tramadol n = 52 (65.8%) and other opioids n = 27 (34.2%) for the RTO group. Participants were phenotyped across multiple domains including demographics, fibromyalgia characteristics pain, fatigue, sleep, psychosocial factors, and activity. Participants were randomized to active TENS (n = 101), placebo TENS (n = 99), or no TENS (n = 99) for 1-month with randomization stratified by opioid use. Active TENS was equally effective in movement-evoked pain in those in the RTO and not-RTO groups. Women with fibromyalgia in the RTO group were older (P = .002), lower-income (P = .035), more likely to smoke (P = .014), and more likely to report depression (P = .013), hypertension (P = .005) or osteoarthritis (P = .027). The RTO group demonstrated greater bodily pain on SF-36 (P = .005), lower quality of life on the physical health component of the SF-36 (P = .040), and greater fatigue (MAF-ADL P = .047; fatigue with sit to stand test (P = .047) These differences were small of and unclear clinical significance. In summary, regular use of opioid analgesics does not interfere with the effectiveness of TENS for movement-evoked pain. Clinical Trial Registration Number: NCT01888640. PERSPECTIVE: Individuals treated with mixed frequency TENS at a strong but comfortable intensity that was taking prescription opioid analgesics showed a significant reduction in movement-evoked pain and fatigue. These data support the use of TENS, using appropriate parameters of stimulation, as an intervention for individuals with fibromyalgia taking opioid analgesics.

The therapeutic efficacy of Qigong exercise on the main symptoms of fibromyalgia: A pilot randomized clinical trial

Background

Some of the most debilitating symptoms of fibromyalgia (FM) include widespread chronic pain, sleep disturbances, chronic fatigue, anxiety, and depression. Yet, there is a lack of effective self-management exercise interventions capable of alleviating FM symptoms. The objective of this study is to examine the efficacy of a 10-week daily Qigong, a mind–body intervention program, on FM symptoms.

Methods

20 participants with FM were randomly assigned to Qigong (experimental) or sham-Qigong (control) groups, with participants blinded to the intervention allocation. The Qigong group practiced mild body movements synchronized with deep diaphragmatic breathing and meditation. The sham-Qigong group practiced only mild body movements. Both groups practiced the interventions two times per day at home, plus one weekly group practice session with a Qigong instructor. Primary outcomes were: pain changes measured by the Short-Form McGill Pain Questionnaire, a visual analog scale for pain, pressure pain threshold measured by a dolorimeter. Secondary outcomes were: the Revised Fibromyalgia Impact Questionnaire the Pittsburgh Sleep Quality Index, the Hospital Anxiety and Depression Scale and the Quality of Life Scale.

Results

The experimental group experienced greater clinical improvements when compared to the control group on the mean score differences of pain, sleep quality, chronic fatigue, anxiety, depression, and fibromyalgia impact, all being statistically significant at p < 0.05.

Conclusion

Daily practice of Qigong appears to have a positive impact on the main fibromyalgia symptoms that is beyond group interaction.

Trial registration

ClinicalTrials.gov NCT03441997.

Antibodies to Human Herpesviruses in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients

Myalgic encephalomyelitis, also referred to as chronic fatigue syndrome (ME/CFS) is a debilitating disease characterized by myalgia and a sometimes severe limitation of physical activity and cognition. It is exacerbated by physical and mental activity. Its cause is unknown, but frequently starts with an infection. The eliciting infection (commonly infectious mononucleosis or an upper respiratory infection) can be more or less well diagnosed. Among the human herpesviruses (HHV-1-8), HHV-4 (Epstein-Barr virus; EBV), HHV-6 (including HHV-6A and HHV-6B), and HHV-7, have been implicated in the pathogenesis of ME/CFS. It was therefore logical to search for serological evidence of past herpesvirus infection/reactivation in several cohorts of ME/CFS patients (all diagnosed using the Canada criteria). Control samples were from Swedish blood donors. We used whole purified virus, recombinant proteins, and synthetic peptides as antigens in a suspension multiplex immunoassay (SMIA) for immunoglobulin G (IgG). The study on herpesviral peptides based on antigenicity with human sera yielded novel epitope information. Overall, IgG anti-herpes-viral reactivities of ME/CFS patients and controls did not show significant differences. However, the high precision and internally controlled format allowed us to observe minor relative differences between antibody reactivities of some herpesviral antigens in ME/CFS versus controls. ME/CFS samples reacted somewhat differently from controls with whole virus HHV-1 antigens and recombinant EBV EBNA6 and EA antigens. We conclude that ME/CFS samples had similar levels of IgG reactivity as blood donor samples with HHV-1-7 antigens. The subtle serological differences should not be over-interpreted, but they may indicate that the immune system of some ME/CFS patients interact with the ubiquitous herpesviruses in a way different from that of healthy controls.

The tibial nerve compression test for the diagnosis of lumbar spinal canal stenosis-A simple and reliable physical examination for use by primary care physicians

Objectives

In the present study, we aimed to evaluate the diagnostic accuracy and suitability of the ‘Tibial Nerve Compression Test (TNCT)’ as a screening tool for lumbar spinal canal stenosis (LSS).

Methods

A total of 108 consecutive patients admitted to our hospital for surgical treatment or diagnosis of LSS were included in this study. Fifty healthy volunteers were examined as a control group. The severity of tenderness was scored (tenderness score) and measured on a visual analogue scale (P-VAS score). These scores were compared between the LSS and control groups. Moreover, they were compared before and after the operation among operated patients.

Results

The positive tenderness rate was significantly higher (92.6% [100/108]) in the LSS group than in the control group (30% [15/50]). The sensitivity and specificity of TNCT (95% confidence interval) were 0.93 (0.88–0.96) and 0.70 (0.61–0.77), respectively. Positive tenderness rates and P-VAS scores were significantly higher in the LSS group (p < 0.0001). Scores on all measures significantly improved post-operatively in operated patients (p < 0.0001).

Conclusion

The Tibial Nerve Compression Test is a useful screening tool for LSS diagnosis in a primary care setting.

Level of evidence

Level II, diagnostic study

Altered fMRI resting-state connectivity in individuals with fibromyalgia on acute pain stimulation

BACKGROUND

Fibromyalgia is a chronic widespread pain condition, with patients commonly reporting other symptoms such as sleep difficulties, memory complaints and fatigue. The use of magnetic resonance imaging (MRI) in fibromyalgia has allowed for the detection of neural abnormalities, with alterations in brain activation elicited by experimental pain and alterations in resting state connectivity related to clinical pain.

METHODS

In this study, we sought to monitor state changes in resting brain connectivity following experimental pressure pain in fibromyalgia patients and healthy controls. Twelve fibromyalgia patients and 15 healthy controls were studied by applying discrete pressure stimuli to the thumbnail bed during MRI. Resting-state functional MRI scanning was performed before and immediately following experimental pressure pain. We investigated changes in functional connectivity to the thalamus and the insular cortex.

RESULTS

Acute pressure pain increased insula connectivity to the anterior cingulate and the hippocampus. Additionally, we observed increased thalamic connectivity to the precuneus/posterior cingulate cortex, a known part of the default mode network, in patients but not in controls. This connectivity was correlated with changes in clinical pain.

CONCLUSIONS

These data reporting changes in resting-state brain activity following a noxious stimulus suggest that the acute painful stimuli may contribute to the alteration of the neural signature of chronic pain. WHAT DOES THIS STUDY/ADD?: In this study acute pain application shows an echo in functional connectivity and clinical pain changes in chronic pain.

A case of fibromyalgia involving pain throughout the body treated with site-specific targeted pain control

Introduction

Fibromyalgia is characterized by chronic pain and tenderness throughout the body. Patients with fibromyalgia are treated with pharmacotherapy and many other therapies. However, because the cause of fibromyalgia is unclear, there is currently no clinically effective treatment method.

Case presentation

We report the case of a patient who developed fibromyalgia after left femoral neck fracture. After several caudal epidural blocks for lumbar pain, the pain throughout the body and abnormal discomfort in the laryngopharyngeal region reduced. Site-specific targeted pain control was effective in treating his pain and discomfort.

Conclusion

The present case suggests that treatment targeting symptoms in one part of the body might produce a systemic therapeutic effect in patients with fibromyalgia.

Perceived function and physical performance are associated with pain and fatigue in women with fibromyalgia

BACKGROUND

Fibromyalgia is a condition characterized by chronic widespread muscle pain and fatigue and associated with significant impairment in perceived function and reduced physical performance. The purpose of this study was to determine the degree to which pain and fatigue are associated with perceived function and physical performance in women with fibromyalgia.

METHODS

Hierarchical linear regression determined the contribution of pain and fatigue (Numeric Rating Scale (NRS) for resting, movement and combined) to perceived function (Fibromyalgia Impact Questionnaire Revised - Function Subscale, FIQR-Function), Multidimensional Assessment of Fatigue - Activities of Daily Living (MAF-ADL) and SF-36 Physical Function Subscale (SF-36-PF) and physical performance (6-Minute Walk Test, 6MWT and Five Time Sit To Stand, 5TSTS) while controlling for age, body mass index, pain catastrophizing, fear of movement, anxiety, and depression in women with fibromyalgia (N = 94).

RESULTS

For perceived function, movement pain and movement fatigue together better predicted FIQR-function (adjusted R(2) = 0.42, p ≤ 0.001); MAF-ADL (adjusted R(2) = 0.41, p ≤ 0.001); and SF-36-PF function (adjusted R(2) = 0.34, p ≤ 0.001). For physical performance measures, movement pain and fatigue together predicted 6MWT distance (adjusted R(2) = 0.42, p ≤ 0.001) and movement fatigue alone predicted performance time on the 5TSTS (adjusted R(2) = 0.20, p ≤ 0.001).

CONCLUSIONS

Pain and fatigue are significantly associated with and explain more than one-third of the variance in perceived function and physical performance in women with fibromyalgia.

TRIAL REGISTRATION

NIH Clinicaltrials.gov

REGISTRATION

NCT01888640 . Registered 13 June 2013.

Relation of dopamine receptor 2 binding to pain perception in female fibromyalgia patients with and without depression--A [¹¹C] raclopride PET-study

Dopamine D2/D3 receptor availability at rest and its association with individual pain perception was investigated using the [(11)C] raclopride PET-method in 24 female Fibromyalgia (FMS) participants with (FMS+, N=11) and without (FMS-, N=13) comorbid depression and in 17 healthy women. Thermal pain thresholds (TPT) and pain responses were assessed outside the scanner. We compared the discriminative capacity, i.e. the individual׳s capacity to discriminate between lower and higher pain intensities and the response criterion, i.e. the subject׳s tendency to report pain during noxious stimulation due to psychological factors. [(11)C] raclopride binding potential (BP), defined as the ratio of specifically bound non-displaceable radioligand at equilibrium (BP(ND)) was used as measure of D2/D3 receptor availability. We found significant group effects of BP(ND) in striatal regions (left ventral striatum, left caudate nucleus and left nucleus accumbens) between FMS+ and FMS- compared to healthy subjects. Correlational analysis showed negative associations between TPT and D2/D3 receptor availability in the left caudate nucleus in FMS-, between TPT and D2/D3 receptor availability in the right caudate nucleus in FMS + and positive associations between TPT and D2/D3 receptor availability in the left putamen and right caudate nucleus in healthy controls. The response criterion was positively associated with D2/D3 receptor availability in the right nucleus accumbens in FMS - and negatively with D2/D3 receptor availability in the left caudate nucleus in healthy controls. Finally, no significant associations between D2/D3 receptor availability and discriminative capacity in any of the groups or regions were determined. These findings provide further support for a disruption of dopaminergic neurotransmission in FMS and implicate DA as important neurochemical moderator of differences in pain perception in FMS patients with and without co-morbid depression.

Laser-Evoked Potentials in Fibromyalgia: The Influence of Greater Occipital Nerve Stimulation on Cerebral Pain Processing

OBJECTIVE

Fibromyalgia causes widespread musculo-skeletal pain in the four quadrants of the body. Greater occipital nerve stimulation has recently shown beneficial effects in fibromyalgia patients on pain, fatigue, and mood disorders. Laser-evoked potentials (LEPs) are used for research to understand the pathophysiological mechanisms of pain and to evaluate the effects of pain treatment. In fibromyalgia patients, LEPs tend to have a higher N2 amplitude, a tendency to shorter latencies, and patients have a lower pain threshold. Greater occipital nerve stimulation might exert a modulation of the medial pain pathways processing the affective motivational components of pain (unpleasantness) as well as the descending pain inhibitory pathways (reducing pain), both of which are contributing to the N2P2 peak.

MATERIALS AND METHODS

To test this hypothesis, the authors performed LEPs in a group of fibromyalgia patients with and without greater occipital nerve stimulation.

RESULTS

Occipital nerve stimulation does not alter the amplitudes of the LEP recordings, although a significant difference in latencies can be seen. More specifically, latencies of the N2P2 increased in the condition after stimulation, and especially at the Pz electrode.

CONCLUSION

Our results suggest Occipital Nerve Stimulation (ONS) induces a modification of the balance between antinociceptive pain inhibitory pathways and pain-provoking pathways.

New Approach in Fibromyalgia Exercise Program: A Preliminary Study Regarding the Effectiveness of Balance Training

OBJECTIVES

To determine the effectiveness of balance exercises on the functional level and quality of life (QOL) of patients with fibromyalgia syndrome (FMS) and to investigate the circumstances associated with balance disorders in FMS.

DESIGN

Randomized controlled trial.

SETTING

Physical medicine and rehabilitation clinic.

PARTICIPANTS

Patients (N=57) (age range, 18-65y) with FMS were randomly assigned into 2 groups.

INTERVENTIONS

Group 1 was given flexibility and balance exercises for 6 weeks, whereas group 2 received only a flexibility program as the control group.

MAIN OUTCOME MEASURES

Functional balance was measured by the Berg Balance Scale (BBS), and dynamic and static balance were evaluated by a kinesthetic ability trainer (KAT) device. Fall risk was assessed with the Hendrich II fall risk model. The Nottingham Health Profile, Fibromyalgia Impact Questionnaire (FIQ), and Beck Depression Inventory (BDI) were used to determine QOL and functional and depression levels, respectively. Assessments were performed at baseline and after the 6-week program.

RESULTS

In group 1, statistically significant improvements were observed in all parameters (P<.05), but no improvement was seen in group 2 (P>.05). When comparing the 2 groups, there were significant differences in group 1 concerning the KAT static balance test (P=.017) and FIQ measurements (P=.005). In the correlation analysis, the BDI was correlated with the BBS (r=-.434) and Hendrich II results (r=.357), whereas body mass index (BMI) was correlated with the KAT static balance measurements (r=.433), BBS (r=-.285), and fall frequency (r=.328).

CONCLUSIONS

A 6-week balance training program had a beneficial effect on the static balance and functional levels of patients with FMS. We also observed that depression deterioration was related to balance deficit and fall risk. Higher BMI was associated with balance deficit and fall frequency.

Effects of xenon irradiation of the stellate ganglion region on fibromyalgia

[Purpose] The aim of the study was to determine the effect of xenon irradiation of the stellate ganglion region on fibromyalgia. [Subjects] The study included 5 men and 22 women (age, 56.4 ± 16.3 years [range, 25–84 years]) who were diagnosed with fibromyalgia according to the modified 2010 criteria of the American College of Rheumatology between July and August 2013. [Methods] Bilateral xenon light irradiation (0.38–1.1 μm) around the stellate ganglion was performed in the supine position by physical therapists using a xenon phototherapy device. We evaluated pain before and after irradiation using the visual analogue scale. [Results] We did not observe a relationship between the change in the visual analogue scale score and duration of fibromyalgia. However, we observed a relationship between the change in the visual analogue scale score and the score for the Japanese version of the Fibromyalgia Impact Questionnaire using the Cochran-Armitage test for trend. [Conclusion] Xenon light irradiation of the stellate ganglion significantly decreased the visual analogue scale score in patients with fibromyalgia having a higher score in the Fibromyalgia Impact Questionnaire, suggesting that a stronger effect could be obtained in patients with more severe fibromyalgia.

Analgesic and anti-hyperalgesic effects of muscle injections with lidocaine or saline in patients with fibromyalgia syndrome

BACKGROUND

Patients with musculoskeletal pain syndrome including fibromyalgia (FM) complain of chronic pain from deep tissues including muscles. Previous research suggests the relevance of impulse input from deep tissues for clinical FM pain. We hypothesized that blocking abnormal impulse input with intramuscular lidocaine would decrease primary and secondary hyperalgesia and FM patients' clinical pain.

METHODS

We enrolled 62 female patients with FM into a double-blind controlled study of three groups who received 100 or 200 mg of lidocaine or saline injections into both trapezius and gluteal muscles. Study variables included pressure and heat hyperalgesia as well as clinical pain. In addition, placebo factors like patients' anxiety and expectation for pain relief were used as predictors of analgesia.

RESULTS

Primary mechanical hyperalgesia at the shoulders and buttocks decreased significantly more after lidocaine than saline injections (p = 0.004). Similar results were obtained for secondary heat hyperalgesia at the arms (p = 0.04). After muscle injections, clinical FM pain significantly declined by 38% but was not statistically different between lidocaine and saline conditions. Placebo-related analgesic factors (e.g., patients' expectations of pain relief) accounted for 19.9% of the variance of clinical pain after the injections. Injection-related anxiety did not significantly contribute to patient analgesia.

CONCLUSION

These results suggest that muscle injections can reliably reduce clinical FM pain, and that peripheral impulse input is required for the maintenance of mechanical and heat hyperalgesia of patients with FM. Whereas the effects of muscle injections on hyperalgesia were greater for lidocaine than saline, the effects on clinical pain were similar for both injectates.

Estrogenic influences in pain processing

Gonadal hormones not only play a pivotal role in reproductive behavior and sexual differentiation, they also contribute to thermoregulation, feeding, memory, neuronal survival, and the perception of somatosensory stimuli. Numerous studies on both animals and human subjects have also demonstrated the potential effects of gonadal hormones, such as estrogens, on pain transmission. These effects most likely involve multiple neuroanatomical circuits as well as diverse neurochemical systems and they therefore need to be evaluated specifically to determine the localization and intrinsic characteristics of the neurons engaged. The aim of this review is to summarize the morphological as well as biochemical evidence in support for gonadal hormone modulation of nociceptive processing, with particular focus on estrogens and spinal cord mechanisms.

Transcutaneous electrical nerve stimulation reduces pain, fatigue and hyperalgesia while restoring central inhibition in primary fibromyalgia

Because transcutaneous electrical nerve stimulation (TENS) works by reducing central excitability and activating central inhibition pathways, we tested the hypothesis that TENS would reduce pain and fatigue and improve function and hyperalgesia in people with fibromyalgia who have enhanced central excitability and reduced inhibition. The current study used a double-blinded randomized, placebo-controlled cross-over design to test the effects of a single treatment of TENS with people with fibromyalgia. Three treatments were assessed in random order: active TENS, placebo TENS and no TENS. The following measures were assessed before and after each TENS treatment: pain and fatigue at rest and in movement; pressure pain thresholds, 6-m walk test, range of motion; 5-time sit-to-stand test, and single-leg stance. Conditioned pain modulation was completed at the end of testing. There was a significant decrease in pain and fatigue with movement for active TENS compared to placebo and no TENS. Pressure pain thresholds increased at the site of TENS (spine) and outside the site of TENS (leg) when compared to placebo TENS or no TENS. During active TENS, conditioned pain modulation was significantly stronger compared to placebo TENS and no TENS. No changes in functional tasks were observed with TENS. Thus, the current study suggests TENS has short-term efficacy in relieving symptoms of fibromyalgia while the stimulator is active. Future clinical trials should examine the effects of repeated daily delivery of TENS, similar to the way in which TENS is used clinically on pain, fatigue, function, and quality of life in individuals with fibromyalgia.

Factors promoting sustainable work in women with fibromyalgia

PURPOSE

To examine and describe the factors promoting sustainable work in women with fibromyalgia (FM).

METHODS

A qualitative interview study. Twenty-seven gainfully employed women with FM participated in five focus group interviews. Their median age was 52 years, ranging from 33 to 62. The interviews were recorded, transcribed verbatim and analysed by qualitative latent content analysis.

RESULTS

Four categories were identified describing factors promoting sustainable work: the meaning of work and individual strategies were individual promoters while a favourable work environment and social support outside work were environmental promoters. The meaning of work included individual meaning and social meaning. The individual strategies included handling symptoms, the work day and long-term work life. A favourable work environment included the physical and psychosocial work environment. Social support outside work included societal and private social supports.

CONCLUSIONS

Promoting factors for work were identified, involving individual and environmental factors. These working women with FM had developed advanced well-functioning strategies to enhance their work ability. The development of such strategies should be supported by health-care professionals as well as employers to promote sustainable work in women with FM.

IMPLICATIONS FOR REHABILITATION

Work disability is a common consequence of fibromyalgia (FM). Working women with FM appear to have developed advanced well-functioning individual strategies to enhance their work ability. The development of individual strategies should be supported by health-care professionals as well as employers to promote sustainable work and health in women with FM.

Evidence-based pain management: is the concept of integrative medicine applicable?

This article is dedicated to the concept of predictive, preventive, and personalized (integrative) medicine beneficial and applicable to advance pain management, overviews recent insights, and discusses novel minimally invasive tools, performed under ultrasound guidance, enhanced by model-guided approach in the field of musculoskeletal pain and neuromuscular diseases. The complexity of pain emergence and regression demands intellectual-, image-guided techniques personally specified to the patient. For personalized approach, the combination of the modalities of ultrasound, EMG, MRI, PET, and SPECT gives new opportunities to experimental and clinical studies. Neuromuscular imaging should be crucial for emergence of studies concerning advanced neuroimaging technologies to predict movement disorders, postural imbalance with integrated application of imaging, and functional modalities for rehabilitation and pain management. Scientific results should initiate evidence-based preventive movement programs in sport medicine rehabilitation. Traditional medicine and mathematical analytical approaches and education challenges are discussed in this review. The physiological management of exactly assessed pathological condition, particularly in movement disorders, requires participative medical approach to gain harmonized and sustainable effect.

Simplifying Fibromyalgia Assessment: The VASFIQ Brief Symptom Scale

OBJECTIVES

We tested the ability of the VASFIQ, a seven-item scale composed of Fibromyalgia Impact Questionnaire (FIQ) visual analog scales (VASs), to quantify fibromyalgia global disease severity and identify fibromyalgia patients with significant symptoms of fatigue, poor sleep, depression or anxiety.

METHODS

Spearman rank correlations were used to compare global VASFIQ, FIQ and Patient Global Impression of Change (PGIC) scores and individual FIQ VAS scores with full-length, validated questionnaire scores for fatigue (Multidimensional Assessment of Fatigue-Global Fatigue Index [MAF-GFI]), poor sleep (Medical Outcomes Study Sleep Problems Index [SPI]) and depression and anxiety (Hospital Anxiety and Depression Scale [HADS]). Patient scores used in the analyses were derived from 2229 patients enrolled in three pregabalin fibromyalgia trials. Receiver operating characteristic analyses determined VASFIQ cutoff scores identifying patients with clinically significant symptom levels using full-length, validated symptom questionnaires to define cases.

RESULTS

Global VASFIQ and FIQ scores correlated highly at baseline and study endpoints (ρ = 0.94 and 0.97, respectively; both p<0.0001). Change in global VASFIQ and FIQ scores correlated similarly to PGIC scores at study endpoints (ρ = 0.58 and 0.61, respectively; both p<0.0001). Individual FIQ VAS scores correlated with corresponding full-length symptom questionnaire scores at baseline and study endpoints (VASfatigue with MAF-GFI, ρ = 0.64 and 0.76; VASsleep with SPI, ρ = 0.50 and 0.67; VASdepression with HADS-D, ρ = 0.43 and 0.62; VASanxiety with HADS-A, ρ = 0.47 and 0.67, respectively; p <0.0001 for all). Patients with significant symptoms of fatigue were identified by VASfatigue >7.5, poor sleep by VASsleep >7.9, depression by VASdepression >5.8 and anxiety by VASanxiety >6.0. VASFIQ global scores ≥31.4 and ≥45.0 identified patients with moderate and severe global fibromyalgia symptoms, respectively.

CONCLUSIONS

The VASFIQ scale accurately quantifies global fibromyalgia severity and identifies patients with significant symptoms of fatigue, poor sleep, depression or anxiety with brevity, enabling rapid patient assessment and informing treatment decisions in busy clinics.

Heritability of chronic pain in 2195 extended families

Chronic pain is pathological, persisting beyond normal tissue healing time. Previous work has suggested ∼50% variation in chronic pain development is heritable. No data are currently available on the heritability of pain categorized using the Chronic Pain Grade (CPG). Furthermore, few existing studies have accounted for potential confounders that may themselves be under genetic control or indeed 'heritable' non-genetic traits. This study aimed to determine the relative contributions of genetic, measured and shared environmental and lifestyle factors to chronic pain. Chronic pain status was determined and CPG measured in participants from Generation Scotland: the Scottish Family Health Study, a large cohort of well-characterized, extended families from throughout Scotland, UK. Heritability estimates (h (2) ) for 'any chronic pain' and 'severe' chronic pain (CPG 3 or 4) were generated using SOLAR software, with and without adjustment for shared household effects and measured covariates age, body mass index, gender, household income, occupation and physical activity. Data were available for 7644 individuals in 2195 extended families. Without adjustment, h (2) for 'any chronic pain' was 29% [standard errors (SE) 6%; p < 0.001], and for 'severe' chronic pain was 44% (SE 3%; p <0.001). After adjustment, 'any chronic pain' h(2) = 16% (SE 7%; p = 0.02) and 'severe' chronic pain h(2) = 30% (SE 13%; p = 0.007). Co-heritability of both traits was 11% (SE 76%). This study supports the use of chronic pain as a phenotype in genetic studies, with adequate correction for confounders to specifically identify genetic risk factors for chronic pain.

Genetic variation in the beta-2 adrenergic receptor is associated with chronic musculoskeletal complaints in adolescents

BACKGROUND

There is significant evidence to suggest that psychological and stress-related factors are important predictors of the onset of chronic widespread pain (CWP) and fibromyalgia (FM). The hypothalamic-pituitary-adrenal axis, together with the efferent sympathetic/adrenomedullary system, influence all body organs (including muscles) during short- and long-term threatening stimuli. The aim of this study was to investigate the relationship between genetic variants in adrenergic candidate genes and chronic musculoskeletal complaints (MSCs) in adolescents.

METHODS

Adolescents from the Western Australian Pregnancy (Raine) Cohort attending the 17-year cohort review completed a questionnaire containing a broad range of psychosocial factors and pain assessment (n = 1004). Blood samples were collected for DNA extraction and genotyping. Genotype data was obtained for 14 single nucleotide polymorphisms (SNPs) in two candidate genes - beta-2 adrenergic receptor (ADRB2) and catecholamine-O-methyltransferase (COMT). Haplotypes were reconstructed for all individuals with genotype data.

RESULTS AND CONCLUSION

Both female gender and poor mental health were associated with (1) an increased risk for chronic, disabling comorbid neck and low back pain (CDCP); and (2) an increase in the number of areas of pain. Of the 14 SNPs evaluated, only SNP rs2053044 (ADRB2, recessive model) displayed an association with CDCP [odds ratio (OR) = 2.49; 95% confidence interval (CI) = 1.25, 4.98; p = 0.01] and pain in three to four pain areas in the last month (OR = 1.86; 95% CI = 1.13, 3.06; p = 0.02). These data suggest that genetic variants in ADRB2 may be involved in chronic MSCs.

Neuroticism in young women with fibromyalgia links to key clinical features

Objective. We examined personality traits in young women with FM, in order to seek associations with key psychological processes and clinical symptoms. Methods. Twenty-seven women with FM and 29 age-matched female healthy controls [HC] completed a series of questionnaires examining FM symptoms, personality and psychological variables. Results. Significant differences between characteristic FM symptoms (sleep, pain, fatigue, and confusion) as well as for the psychological variables of depression, anxiety, and stress were found between FM and HC (P < 0.001). Neuroticism was the only subscale of the Big Five Inventory that showed a significant difference between the FM group and HC group [P < 0.05]. Within the FM group, there was a significant association between the level of the neuroticism and each of pain, sleep, fatigue, and confusion, depression, anxiety, and stress (P < 0.05–0.01). The association between the level of neuroticism and the level of stress was the strongest of all variables tested (P < 0.001). Conclusion. The personality trait of neuroticism significantly associates with the key FM characteristics of pain, sleep, fatigue and confusion as well as the common co-morbidities of depression, anxiety and stress. Personality appears to be an important modulator of FM clinical symptoms.

Central amplification and fibromyalgia: disorder of pain processing

Fibromyalgia (FM), a complex chronic pain disorder affecting a heterogeneous patient population, is an area of active basic and clinical research. Although diagnostic criteria for FM have been available for 2 decades, there remains no definitive diagnostic and no consensus regarding its etiology. Accumulating evidence suggests the underlying cause of FM pain results from abnormal pain processing particularly in the central nervous system rather than from dysfunction in peripheral tissues where pain is perceived. In this review, we examine recent studies investigating abnormalities in central pain processing as a component of FM in both preclinical models of generalized muscle hypersensitivity and clinical research in patients with FM. We focus our discussion on two areas where strong evidence exists for abnormalities in sensory signaling: the reduction of descending control, including suppression of descending inhibitory pathways and/or enhancement of descending facilitatory pathways, and changes in key neurotransmitters associated with central sensitization. Finally, we discuss currently available pharmacological treatments indicated for the management of pain in FM patients, based on their proposed mechanism of action and efficacy.

Is Chiari I malformation associated with fibromyalgia?

BACKGROUND

The symptoms of Chiari I Malformation (CIM) and fibromyalgia (FM) overlap. Some FM patients have been surgically treated for presumed CIM-type pathology.

OBJECTIVE

To determine whether CIM is more common among FM patients than pain- and fatigue-free controls.

METHODS

One hundred seventy-six participants with FM and 67 pain- and fatigue-free control subjects underwent magnetic resonance imaging of the brain and upper cervical spine. Posterior fossa cerebrospinal fluid flow was assessed with cardiac gated cine phase-contrast imaging at the craniocervical region. CIM was defined as inferior extension of cerebellar tonsils ≥ 5 mm below the basion-opisthion line of the foramen magnum or tonsillar position 3 to 5 mm below the basion-opisthion line plus abnormalities of CSF flow, posterior fossa volume, or hindbrain or cervical spinal cord movement. Visual analog scales, questionnaires, and interviews were used to collect data on sleep quality, fatigue, pain, and headache. We used regression techniques to examine the association of outcome measures with disease status and the Fisher exact test to compare the CIM prevalence in the 2 groups.

RESULTS

The FM group was older (mean age, 50 vs 40 years) and more likely to be white (89% vs 73%) and female (93% vs 54%; P < .01). Mean tonsillar position and the prevalence of CIM (2.8% vs 4.5%; P = .69) were similar in the FM and control groups. FM patients experienced more headaches, pain, fatigue, and sleep disturbances than control subjects (P < .01).

CONCLUSION

Most patients with FM do not have CIM pathology. Future studies should focus on dynamic neuroimaging of craniocervical neuroanatomy in patients with FM.

A comparison of the clinical features of fibromyalgia syndrome in different settings

BACKGROUND

The "funnel hypothesis" of fibromyalgia syndrome (FMS) assumes that the high levels of somatic and psychological symptoms reported by FMS-patients are due to a selection bias of patients seeking for medical specialist care. We tested the hypothesis by comparing FMS-patients from a general population sample and different clinical settings.

METHODS

From a cross-sectional survey of a representative sample of the German general population, persons meeting FMS-criteria were selected. Consecutive in- and outpatients from German rheumatology, pain medicine, psychosomatic medicine and integrative medicine settings with established or initial diagnosis of FMS were recruited. FMS was diagnosed in all samples by the survey criteria of the regional pain scale. Somatic symptom intensity was measured by 13 items of the Patient Health Questionnaire PHQ 15, depressed mood by the 9-items PHQ 9.

RESULTS

96 persons of the general population, 86 of the rheumatology, 80 of the pain medicine, 69 of the psychosomatic medicine and 58 of the integrative medicine setting were included into the comparison. Patients of the clinical settings reported more pain sites and more somatic and depressive symptoms than FMS-persons of the general population. Patients of the different clinical settings did not differ in the number of pain sites and the intensity of depressive and somatic symptoms.

CONCLUSIONS

We found a "funnel" between FMS-persons of the general population and FMS-patients of clinical settings, but not between patients of different levels of care. Patients contacting the health care system did not differ in clinical features.

Reconstruction of nasal deformity in Wegener's granulomatosis: contraindication or benefit?

BACKGROUND

Saddle-nose deformity is a well-recognized stigma of patients affected by Wegener granulomatosis (WG). However, plastic surgical repair is seldom performed. In this study, the authors aimed to evaluate their own patients exclusively reconstructed by costal cartilage L-strut of the nose for this specific deformity.

METHODS

During a 5-year-period, four women with an average age of 33 years underwent reconstructive rhinoplasty of their saddle-nose deformity caused by WG, which in every case was in remission regarding the nose at the time of surgery. Restoration of the nasal framework was performed by an L-shaped rib cartilage graft.

RESULTS

The external form and function of the newly reconstructed nose was preserved during an average follow-up period of 42 months for all the patients. No resorption of the rib cartilage graft was observed. A review of the literature found a total of 22 nasal reconstructions for patients affected by WG.

CONCLUSION

According to this patient series and a review of the literature, external nasal reconstruction for patients affected by WG appears to be safe and effective if the disease is in remission before any operation. Despite concern that high-dose immune suppression therapy may increase the risk of failure in primary nasal dorsal repair, this could not be observed in the patients of this series, all of whom were receiving immunosuppressive medication. Therefore, nasal reconstruction to improve the physical appearance and thus the psychological well-being of these chronically ill patients seems to be justified.

Attenuation of experimental pain by vibro-tactile stimulation in patients with chronic local or widespread musculoskeletal pain

Patients with chronic pain syndromes, like fibromyalgia (FM) complain of widespread pain and tenderness, as well as non-refreshing sleep, cognitive dysfunction, and negative mood. Several lines of evidence implicate abnormalities of central pain processing as contributors for chronic pain, including dysfunctional descending pain inhibition. One form of endogenous pain inhibition, diffuse noxious inhibitory controls (DNIC), has been found to be abnormal in some chronic pain patients and evidence exists for deficient spatial summation of pain, specifically in FM. Similar findings have been reported in patients with localized musculoskeletal pain (LMP) disorders, like neck and back pain. Whereas DNIC reduces pain through activation of nociceptive afferents, vibro-tactile pain inhibition involves innocuous A-beta fiber. To assess whether patients with localized or widespread chronic pain disorders have dysfunctional A-beta related pain inhibition we enrolled 28 normal pain-free controls (NC), 29 FM patients, and 19 subjects with neck or back pain. All received 10s sensitivity-adjusted noxious heat stimuli to the forearms as test stimuli. To assess endogenous analgesic mechanisms of study subjects, vibro-tactile conditioning stimuli were simultaneously applied with test stimuli either homotopically or heterotopically. Additionally, the effect of distraction on experimental pain was assessed. Homotopic vibro-tactile stimulation resulted in 40% heat pain reductions in all subject groups. Distraction did not seem to affect experimental pain ratings.

CONCLUSIONS

Vibro-tactile stimulation effectively recruited analgesic mechanisms not only in NC but also in patients with chronic musculoskeletal pain, including FM. Distraction did not seem to contribute to this analgesic effect.

Pilot study assessing balance in women with fibromyalgia syndrome

The purpose of current study was to assess postural control and balance self-efficacy in people with fibro-myalgia syndrome [FMS]. Thirty-two females with FMS completed the Activity-specific Balance Confidence Scale, Berg Balance test, NeuroCom Balance Master sensory-organization test, and limits of stability. There was a high prevalence of reported falls and a low mean score on the Activity-specific Balance Confidence Scale. A significant number of subjects scored below the population norm fifth percentile score on the sensory-organization test composite, visual, and vestibular sections. Preliminary evidence suggests that women with FMS may present with deficits in postural control, sensory organization, and balance self-efficacy.

Patient-centered perspective on treatment outcomes in chronic pain

OBJECTIVE

To define patient-determined success criteria for fibromyalgia and back pain treatment across four outcome domains: pain, fatigue, emotional distress, interference with daily activities.

DESIGN

Retrospective correlational clinical sample design.

SETTING

Tertiary care clinics at health science center.

PATIENTS

248 fibromyalgia patients and 52 back pain patients.

INTERVENTIONS

N/A.

OUTCOME MEASURES

Patient Centered Outcomes Questionnaire, measures of usual pain intensity and pain unpleasantness.

RESULTS

Overall, for treatment to be considered successful, fibromyalgia patients required pain levels of 3.30 (54% reduction), fatigue levels of 3.08 (60% reduction), distress levels of 2.49 (60% reduction), and interference levels of 2.67 (63% reduction). Comparatively, back pain patients required pain levels of 2.23 (58% reduction), fatigue levels of 2.29 (57% reduction), distress levels of 1.65 (67% reduction), and interference levels of 1.81 (68% reduction). Overall, both fibromyalgia and back pain patients did not expect to meet their criteria for success.

CONCLUSIONS

Results highlight the importance of assessing the patient's view of successful outcome. Both fibromyalgia and back pain patients appear to have stringent criteria for success that existing treatments are often unlikely to meet. Comparison across groups indicated fibromyalgia patients have higher usual levels of pain, fatigue, distress, and interference. Interestingly, fibromyalgia patients also require greater changes across domains in order to consider treatment successful, despite rating higher levels of pain, fatigue, distress, and interference as successful. Recognizing patients' success criteria and treatment expectations encourages discussion and development of individualized treatment goals, and wider implementation of individualized treatment for chronic-pain populations is encouraged.

Objective measures of disordered sleep in fibromyalgia

OBJECTIVE

Patients with fibromyalgia syndrome (FM) complain of inadequate sleep, which could contribute to common symptoms including sleepiness, fatigue, or pain. However, measures that consistently and objectively distinguish FM patients remain elusive.

METHODS

Fifteen women with FM and 15 age- and gender-matched controls underwent 3 nights of polysomnography; Multiple Sleep Latency Tests to assess sleepiness; testing of auditory arousal thresholds during non-REM stage 2 and stage 4 sleep; overnight assessment of urinary free cortisol; and analysis of 24-hour heart rate variability.

RESULTS

On the second night of polysomnography, women with FM in comparison to controls showed more stage shifts (p = 0.04) but did not differ significantly on any other standard polysomnographic measure or on the Multiple Sleep Latency Tests. Alpha EEG power during deep non-REM sleep, alone or as a proportion of alpha power during remaining sleep stages, also failed to distinguish the groups, as did auditory arousal thresholds. Urinary free cortisol did not differ between FM and control subjects in a consistent manner. However, decreased short-term heart rate variability (HRV) and especially ratio-based HRV among FM subjects suggested diminished parasympathetic and increased sympathetic activity, respectively. Other HRV measures suggested decreased complexity of HRV among the FM subjects.

CONCLUSION

Standard measures of sleep, a gold-standard measure of sleepiness, quantified alpha-delta EEG power, auditory arousal thresholds, and urinary free cortisol largely failed to distinguish FM and control subjects. However, HRV analyses showed more promise, as they suggested both increased sympathetic activity and decreased complexity of autonomic nervous system function in FM.

Comparing fibromyalgia patients from primary care and rheumatology settings: clinical and psychosocial features

The aim of this study was to compare clinical symptoms, perceived health status, health resource use and psychosocial features in fibromyalgia (FM) patients at different health care levels. A total of 315 participants were recruited from primary care (PC) (n=101) and rheumatology settings (RS) (n=214). Subjects completed a protocol of clinical features and health resource use, hospital anxiety and depression scale, sickness impact profile, chronic pain self-efficacy scale, multidimensional pain locus of control scale, perceived health competence scale and chronic pain coping inventory. Student's t test, effect size, and contrast and power test were performed to examine differences between samples. FM patients treated in PC and RS were similar in most variables assessed and only differed significantly in tender points, sleep disturbance, wellness-focused coping strategies and in self-efficacy beliefs. The similarities do not support patient selection through care levels and thus, in the Spanish health care system at least, endorse PC as a reference unit for treatment and questioning the benefits of referring patients to RS.

Sleep stage dynamics in fibromyalgia patients and controls

OBJECTIVE

To determine whether previously described sleep stage dynamics, reflecting the mean duration of specific sleep stages, may have clinical utility in a sample of patients with fibromyalgia syndrome (FMS) and controls.

METHODS

Women with FMS (n=15, screened to exclude other sleep disorders) and age-matched women in good health (n=15) were studied with nocturnal polysomnography, multiple sleep latency tests, 2-week pain diaries, and a measure of current pain intensity.

RESULTS

The FMS subjects, in comparison to controls, did not show differences in several common polysomnographic measures, except for increased numbers of stage shifts (126+/-27 vs. 107+/-22, p=.042). Mean durations for episodes of total sleep, stage 1 sleep, stage 3/4 sleep, and rapid eye movement sleep failed to distinguish FMS and control subjects (Wilcoxon rank sum tests, p>.10 for each), but those for stage 2 sleep were shorter in the FMS subjects (p=.006), possibly because transitions to stage 3/4 sleep occurred more quickly (p=.036). Shorter stage 2 sleep durations predicted higher pain diary scores (Spearman rho=-.56, p=.0014) and current pain intensity (rho=-.71, p<0.0001).

CONCLUSIONS

Sleep stage dynamic, and, more specifically, shorter durations of sleep stage 2 periods, distinguish FMS and control female subjects and may predict pain levels experienced in FMS. Analysis of the lengths of individual sleep stages, in addition to the usual sleep stage amounts and percentages listed in standard polysomnogram reports, may have clinical utility.

Low intensity permanent magnets in the treatment of chronic lumbar radicular pain

We assessed the pain-relieving efficacy of static magnetic fields produced by 200 Gauss (G) magnets compared with 50G magnets in a double-blind, randomized, two-phase crossover study in patients with chronic lumbar radicular pain. The surface field strengths of the magnets were 200 and 50G. Phase I included four random periods of two-week duration: two periods with 200G, one period with 50G, and one period of "no treatment." The magnets were positioned either vertically or horizontally in standard lumbosacral elastic corsets. Phase II consisted of two five-week periods with the most effective magnet from Phase I and its corresponding 50 or 200G device. The primary outcome was average daily leg pain score (0-10 scale) in each period of Phase II. Thirty-eight of 40 randomized patients completed Phase I, and 28 of 31 Phase II participants completed the study. In Phase I, pain scores did not differ significantly between 200 and 50G magnets. Phase II average leg pain scores tended to be lower with 200 vs. 50G magnets (3.2+/-2.1 for 200G vs. 3.9+/-2.2 for 50G magnets [P=0.08]) after excluding one unblinded patient. The relative treatment effect of the 200G magnets appeared to increase throughout the five-week period. Although these data cannot rule out a chance effect, the positive trends suggest that larger, longer-duration, sham-controlled trials with 200G magnets be considered in patients with chronic lumbar radicular pain.

Sleep-disordered breathing among women with fibromyalgia syndrome

BACKGROUND

In clinical practice, polysomnograms ("sleep studies") are seldom ordered for patients with fibromyalgia, although sleep issues dominate the symptom complex. One reason for this is the lack of understanding how information from these studies could aid clinical decisions.

METHODS

The authors conducted a chart review of one rheumatologist's community-based practice where polysomnograms were offered routinely to all women who met the American College of Rheumatology criteria for fibromyalgia. Interpretation of these standardized protocol-based polysomnograms was performed by a board-certified neurologist using standard criteria.

RESULTS

Mean age of the study subjects (n = 23) was 45 (standard deviation, 7.8) years. Median body mass index was 27 kg/m2 (interquartile range 20-48). These women had poor sleep with many arousals (median arousal index 23), apnea-hypopneas (median apnea-hypopnea index 22, interquartile range 17-30). Desaturation was common with half the patients having nadir oxygen saturation less than 87%. Restless legs were detected in polysomnograms among many women who clinically denied it (mean leg movement index 5.8).

CONCLUSIONS

A large proportion of women with fibromyalgia in a general rheumatology practice had sleep-disordered breathing, which can be detected using sleep polysomnograms. Studies are needed to examine if treatment of the commonly detected sleep apnea will have a beneficial effect on symptoms of fibromyalgia.

Is further evaluation for growth hormone (GH) deficiency necessary in fibromyalgia patients with low serum insulin-like growth factor (IGF)-I levels?

OBJECTIVE

Fibromyalgia (FM) is characterized by diffuse pain, fatigue, and sleep disturbances; symptoms that resemble the adult growth hormone (GH) deficiency syndrome. Many FM patients have low serum GH levels, with a hypothesized aetiology of dysregulated GH/insulin-like growth factor (IGF)-I axis. The aim of this study was to assess the GH reserve in FM patients with low serum IGF-I levels using the GH-releasing hormone (GHRH)-arginine test.

DESIGN

We retrospectively reviewed the GHRH-arginine data of 77 FM patients with low serum IGF-I levels referred to our tertiary unit over a 4-year period.

RESULTS

Of the 77 FM patients, 13 patients (17%) failed the GHRH-arginine test. Further evaluation with pituitary imaging revealed normal pituitary glands (n=7), coincident microadenomas (n=4), empty sella (n=1) and pituitary cyst (n=1), and relevant medical histories such as previous head injury (n=4), Sheehan's syndrome (n=1), and whiplash injury (n=1). In contrast, the remaining 64 patients (83%) that responded to the GHRH-arginine test demonstrated higher peak GH levels compared to age and BMI-matched controls (n=24).

CONCLUSION

Our data shows that a subpopulation of FM patients with low serum IGF-I levels will fail the GHRH-arginine test. We, thus, recommend that the GH reserve of these patients should be evaluated further, as GH replacement may potentially improve the symptomatology of those with true GH deficiency. Additionally, the increased GH response rates to GHRH-arginine stimulation in the majority of FM patients with low serum IGF-I levels further supports the hypothesis of a dysregulated GH/IGF-I axis in the pathophysiology of FM.