Fibromyalgia

Clinical Effects of Repetitive Transcranial Magnetic Stimulation of the Motor Cortex Are Associated With Changes in Resting-State Functional Connectivity in Patients With Fibromyalgia Syndrome

In this double-blinded, sham-controlled, counterbalanced, and crossover study, we investigated the potential neuroplasticity underlying pain relief and daily function improvements following repetitive transcranial magnetic stimulation of the motor cortex (M1-rTMS) in fibromyalgia syndrome (FMS) patients. Specifically, we used magnetic resonance imaging (MRI) to examine changes in brain structural and resting-state functional connectivity (rsFC) that correlated with improvements in FMS symptomology following M1-rTMS. Twenty-seven women with FMS underwent real and sham treatment series, each consisting of 10 daily treatments of 10Hz M1-rTMS over 2 weeks, with a washout period in between. Before and after each series, participants underwent anatomical and resting-state functional MRI scans and questionnaire assessments of FMS-related clinical pain and functional and psychological burdens. The expected reductions in FMS-related symptomology following M1-rTMS occurred with the real treatment only and correlated with rsFC changes in brain areas associated with pain processing and modulation. Specifically, between the ventromedial prefrontal cortex and the M1 (t = -5.54, corrected P = .002), the amygdala and the posterior insula (t = 5.81, corrected P = .044), and the anterior and posterior insula (t = 6.01, corrected P = .029). Neither treatment significantly changed brain structure. Therefore, we provide the first evidence of an association between the acute clinical effects of M1-rTMS in FMS and functional alterations of brain areas that have a significant role in the experience of chronic pain. Structural changes could potentially occur over a more extended treatment period. PERSPECTIVE: We show that the neurophysiological mechanism of the improvement in fibromyalgia symptoms following active, but not sham, rTMS applied to M1 involves changes in resting-state functional connectivity in sensory, affective and cognitive pain processing brain areas, thus substantiating the essence of fibromyalgia syndrome as a treatable brain-based disorder.

Constructing the Gendered Risk of Illness in Lyrica Ads for Fibromyalgia: Fear of Isolation as a Motivating Narrative for Consumer Demand

Direct-to-consumer television advertisements for Lyrica in the United States create narratives of gendered domestic normalcy to which women with fibromyalgia are encouraged to aspire through pharmaceutical intervention. This paper unpacks images and narratives within these advertisements to demonstrate that they rely on metaphors that represent gendered expectations in order to evoke guilt and provoke a desire for what Joseph Dumit calls "health as risk reduction," and what I argue is an attempt to show disability being erased. Following Stuart Hall's Encoding/Decoding model of communication, viewers play a role in constructing societal expectations for women with chronic pain and for themselves.

Performance of the 2016 diagnostic criteria for fibromyalgia in a tertiary care pain rehabilitation setting: a diagnostic accuracy study

OBJECTIVES

With the International Classification of Diseases 11th revision (classifying fibromyalgia as a primary pain disorder) soon to be implemented, the importance of pain physicians being able to identify patients with fibromyalgia is emphasized. The diagnostic criteria proposed in 2016 are based on self-reported pain distribution and symptom severity. The study aimed to evaluate the diagnostic accuracy of the 2016 diagnostic criteria for fibromyalgia applied in a population of patients with high impact chronic pain referred for pain rehabilitation.

METHODS

The study was performed as a diagnostic accuracy study at two Danish interdisciplinary pain rehabilitation centers, including 215 participants. All participants were evaluated clinically to identify patients with fibromyalgia. The diagnosis was based on expert opinion, but the minimum requirements were: (1) pain in all four body quadrants and axially for at least three months and (2) minimum 8 of 18 positive tender points. Participants filled in the fibromyalgia survey questionnaire, the patient version of the 2016 diagnostic criteria. Sensitivity, specificity, likelihood ratios, and positive and negative post-test probabilities were calculated using a clinical diagnosis of fibromyalgia as the reference standard.

RESULTS

Based on clinical diagnosis 45% of the participants were diagnosed with fibromyalgia; of these, only 19% had been diagnosed previously. The 2016 diagnostic criteria demonstrated a sensitivity of 88.5%, a specificity of 81.5%, a positive likelihood ratio of 4.79, a negative likelihood ratio of 0.14, a positive post-test probability of 79.4%, and a negative post-test probability of 10.2%.

CONCLUSIONS

Fibromyalgia was severely under-diagnosed among patients with high impact chronic pain referred to tertiary care in two pain rehabilitation centers in Denmark. The 2016 diagnostic criteria showed sufficient discriminatory properties suggesting that the fibromyalgia survey questionnaire can be used as a screening tool assisting the identification of fibromyalgia in this patient population.

The Role of Nutrient Supplementation in the Management of Chronic Pain in Fibromyalgia: A Narrative Review

INTRODUCTION

The multifaceted clinical presentation of fibromyalgia (FM) supports the modern understanding of the disorder as a more global condition than one simply affecting pain sensation. The main pharmacologic therapies used clinically include anti-epileptics and anti-depressants. Conservative treatment options include exercise, myofascial release, psychotherapy, and nutrient supplementation.

METHODS

Narrative review.

RESULTS

Nutrient supplementation is a broadly investigated treatment modality as numerous deficiencies have been linked to FM. Additionally, a proposed link between gut microbiome patterns and chronic pain syndromes has led to studies investigating probiotics as a possible treatment. Despite positive results, much of the current evidence regarding this topic is of poor quality, with variable study designs, limited sample sizes, and lack of control groups.

CONCLUSIONS

The etiology of FM is complex, and has shown to be multi-factorial with genetics and environmental exposures lending influence into its development. Preliminary results are promising, however, much of the existing evidence regarding diet supplementation is of poor quality. Further, more robust studies are needed to fully elucidate the potential of this alternative therapeutic option.

The Role of Vitamin D in the Management of Chronic Pain in Fibromyalgia: A Narrative Review

INTRODUCTION

Fibromyalgia (FM) is a complex disorder characterized primarily by chronic, widespread musculoskeletal pain. Currently, the Food and Drug Administration (FDA) has approved the use of three medications to treat FM: pregabalin, duloxetine, and milnacipran. The pharmaceutical intervention has lacked consistent pain relief among all patients. Therefore, the investigation into alternative treatment options has grown in interest. This narrative review aims to evaluate the evidence regarding vitamin D for the treatment of FM.

METHODS

Narrative review.

RESULTS

Low serum vitamin D has been linked to various chronic pain states. An association between vitamin D deficiency and FM has been reported but is controversial in the literature. Some studies have documented the beneficial effects of vitamin D supplementation on reducing pain symptoms and improving the overall quality of life in those with FM. Despite these positive findings, many of the studies regarding this topic lack adequate power to make substantial conclusions about the effects of vitamin D on FM.

CONCLUSION

Existing studies provide promising results. However, additional high-quality data on vitamin D supplementation is needed before recommendations for pain management can be made. Vitamin D supplementation is inexpensive, has minimal side effects, and can benefit FM patients regardless of its efficacy in pain control. Additionally, high-quality studies are warranted to fully elucidate the potential of vitamin D to manage chronic pain in FM.

A Cross-Sectional Study on Central Sensitization and Autonomic Changes in Fibromyalgia

Fibromyalgia is a multi-symptomatic disorder characterized by generalized pain. The pathophysiology of fibromyalgia is supposedly an interplay between central nervous system hyper-responsiveness, autonomic dysfunction, and peripheral pain. In this cross-sectional study, the objective was to assess central sensitization and autonomic activity in patients with fibromyalgia compared with control. Fifty adults diagnosed with fibromyalgia by the modified American College of Rheumatology 2010 criteria and an equal number of age- and sex-matched controls participated in the study in an urban tertiary care hospital. Central sensitization was assessed by history and by evidence of increased prefrontal cortical activity as measured by cortical oxygenation using functional near-infrared spectroscopy. Autonomic activity was assessed by heart rate variability, electrodermal activity, and deep breathing test in three physiological states: rest, sympathetic stress (cold pressor test), and deep breathing. Mann–Whitney U-test, paired t-test, Wilcoxon test, and Friedman test with Bonferroni a priori were used to analyze the data. Cortical activity was significantly higher in the fibromyalgia group than control. There was no significant difference in autonomic activity between the fibromyalgia and control groups. In the fibromyalgia group, variable degrees of sympathetic hyperactivity and normal parasympathetic activity were observed. Central sensitization may be playing a primary role in the pathophysiology of generalized pain in fibromyalgia.

Fibromyalgia Increases the Risk of Surgical Complications Following Total Knee Arthroplasty: A Nationwide Database Study

BACKGROUND

Although fibromyalgia is a common comorbidity with knee osteoarthritis, the orthopedic literature on this population is limited. Therefore, the purpose of this study is to assess if fibromyalgia patients have a higher likelihood of developing surgical complications after total knee arthroplasty (TKA) than a matched control cohort.

METHODS

The Medicare Standard Analytical Files of the PearlDiver supercomputer was utilized to identify patients who underwent a TKA between 2005 and 2014. Patients were 1:1 propensity score matched based on the diagnosis of fibromyalgia, age, gender, and the Charlson Comorbidity Index, yielding a total of 305,510 patients. Odds ratios (ORs), 95% confidence intervals (95% CIs), and P-values (<.05) were calculated to examine the likelihood of developing any surgical complication, as well as specific surgical complications.

RESULTS

Compared to a matched cohort, fibromyalgia patients had increased odds of developing any surgical complication (OR 1.55, 95% CI 1.51-1.60, P < .001), such as bearing wear (OR 2.11, 95% CI 1.48-3.01, P < .0001) and periprosthetic osteolysis (OR 1.71, 95% CI 1.10-2.66, P = .018). Furthermore, these patients had significantly greater odds of developing revision of tibial insert (OR 1.5, 95% CI 1.14-2.05, P = .046), mechanical loosening (OR 1.34, 95% CI 1.26-1.53, P < .0001), infection/inflammation (OR 1.33, 95% CI 1.26-1.14, P < .0001), dislocations (OR 1.33, 95% CI 1.21-1.47, P < .0001), as well as other complications (OR 1.74, 95% CI 1.68-1.80, P < .0001).

CONCLUSION

This analysis of over 300,000 patients identified that fibromyalgia patients can have a greater risk of developing certain surgical complications after TKA. Therefore, fibromyalgia patients must be made aware of the increased postoperative risks and surgeons should consider enhanced preoperative medical and surgical optimization.

Comparing Verum and Sham Acupuncture in Fibromyalgia Syndrome: A Systematic Review and Meta-Analysis

OBJECTIVES

Acupuncture is often used for relieving symptoms of fibromyalgia syndrome (FMS). Our aim is to ascertain whether verum acupuncture is more effective than sham acupuncture in FMS.

METHODS

We collected RCTs to investigate the effects of verum acupuncture and sham acupuncture on pain, sleep quality, fatigue, and general status in FMS patients. The databases used for data retrieval were PubMed, Central Cochrane, EMBASE, PsycINFO, CNKI, VIP, OASIS, KoreaMed, and RISS. Selection/exclusion from the retrieved records was performed according to prespecified criteria, and the final selected records were assessed according to the Cochrane risk of bias tool. The results of the included trials were synthesized on the basis of outcomes, and subgroup analysis depended on the type of add-on sham acupuncture that was performed.

RESULTS

Ten RCTs (690 participants) were eligible, and eight RCTs were eventually included in the meta-analysis. The synthesis showed a sizable effect of verum acupuncture compared with sham acupuncture on pain relief (standardized mean difference (SMD) -0.49, Z = 3.26, P=0.001; I 2 = 59%), improving sleep quality (SMD -0.46, Z = 3.24, P=0.001; I 2 = 0%), and reforming general status (SMD -0.69, Z = 6.27, P < 0.00001; I 2 = 4%). However, efficacy on fatigue was insignificant (SMD -0.10, Z = 0.51, P=0.61; I 2 = 46%). When compared with a combination of simulation and improper location of needling, the effect of verum acupuncture for pain relief was the most obvious.

CONCLUSIONS

Verum acupuncture is more effective than sham acupuncture for pain relief, improving sleep quality, and reforming general status in FMS posttreatment. However, evidence that it reduces fatigue was not found.

Screening for Adult ADHD in Patients with Fibromyalgia Syndrome

Objective

Fibromyalgia syndrome (FMS) is a common chronic pain disorder associated with altered activity of neurotransmitters involved in pain sensitivity such as dopamine, serotonin, and noradrenaline. FMS may significantly impact an individual's functioning due to the presence of chronic pain, fatigue, and cognitive impairment. Dyscognition may be more disabling than the chronic pain but is mostly under-recognized. This study aimed to assess the potential co-occurrence of FMS and adult attention deficit hyperactivity disorder (ADHD), a chronic neurodevelopmental disorder also associated with impaired cognition and dopaminergic function.

Methods

In a cross-sectional observational study, 123 previously confirmed FMS patients were screened for adult ADHD using the World Health Organization Adult ADHD Self Report scale v1.1. The Revised Fibromyalgia Impact Questionnaire (FIQ-R) was used to assess the impact of FMS. Cognitive assessment was based on self-report in accordance with the 2011 modified American College of Rheumatology criteria and the FIQ-R, respectively.

Results

Of the 123 participants, 44.72% (N = 55) screened positive for adult ADHD. Participants with both FMS and a positive adult ADHD screening test scored higher on the FIQ-R score (64.74, SD = 17.66, vs 54.10, SD = 17.10). Self-reported cognitive impairment was rated higher in the combined group (odds ratio = 10.61, 95% confidence interval; 3.77-29.86, P < 0.01).

Conclusions

These results indicate that the co-occurrence of adult ADHD in FMS may be highly prevalent and may also significantly impact the morbidity of FMS. Patients with FMS should be assessed for the presence of adult ADHD.

A nationwide comparative analysis of medical complications in fibromyalgia patients following total knee arthroplasty

Background

Fibromyalgia is a disease primarily characterized by chronic widespread pain and associated symptoms of fatigue, mild cognitive impairment, and sleep disturbance. The condition affects 1% to 6% of the general population in the United States and is more commonly diagnosed in women (2:1 ratio). There is evidence to suggest that fibromyalgia patients may be more at risk of postoperative complications. The rate of total knee arthroplasties (TKAs) performed worldwide is escalating and thus it is expected that the proportion of fibromyalgia patients under orthopaedic care will increase accordingly. However, the literature on TKA outcomes in this subpopulation is limited. We assessed whether fibromyalgia patients have a higher likelihood of developing medical complications compared to a matched cohort of non-fibromyalgia patients following TKA. Specifically, we assessed the likelihood of developing (I) any medical complication and (II) specific medical complications.

Methods

Using the Medicare Standard Analytical Files of the PearlDiver supercomputer, patients who underwent a TKA between 2005 and 2014 were queried. Propensity score matching was used to match patients with and without fibromyalgia in a 1:1 ratio based on age, sex, and the Charlson Comorbidity Index (CCI). A total cohort of 305,510 patients (female =242,198; male =59,810; and unknown =3,502) with (n=152,755) and without fibromyalgia (n=152,755) was identified. Statistical analyses involved the calculation of odds ratios, 95% confidence intervals (95% CI), and P values (<0.05) were utilized to evaluate the occurrence of any and specific medical complications.

Results

Compared to a matched cohort of non-fibromyalgia patients, fibromyalgia patients had increased odds of developing any medical complication following TKA [odds ratio (OR): 1.95, 95% CI: 1.86-2.04, P<0.001]. Furthermore, compared to a matched cohort, these patients had significantly greater odds of developing urinary tract infections (OR: 2.08, 95% CI: 1.89-2.29, P<0.001), acute post-hemorrhagic anemia (OR: 1.56, 95% CI: 1.41-1.73, P<0.001), thoracic or lumbosacral neuritis or radiculitis (OR: 5.85, 95% CI: 4.82-7.10, P<0.001), shortness of breath (OR: 3.02, 95% CI: 2.60-3.51, P<0.001), other diseases of lung not elsewhere classified (OR: 2.32, 95% CI: 1.77-3.03, P<0.001), other respiratory abnormalities (OR: 3.49, 95% CI: 2.87-4.24, P<0.001), transfusion of packed cells (OR: 1.69, 95% CI: 1.36-2.10, P<0.001), pneumonia (OR: 2.17, 95% CI: 1.71-2.76, P<0.001), acute kidney failure (OR: 1.27, 95% CI: 1.02-1.57, P<0.05), and neuralgia neuritis and radiculitis (OR: 5.29, 95% CI: 3.53-7.92, P<0.001).

Conclusions

As the number of fibromyalgia patients under orthopaedic care is expected to rise, it is imperative that the TKA outcomes of these patients are tracked in order to provide optimal patient care. This study identified fibromyalgia as a risk factor for a number of medical complications following TKA. Orthopaedic surgeons must be aware of the potential for poor TKA outcomes among these patients and should provide them with appropriate medical care and pre-operative guidance.

Milnacipran poorly modulates pain in patients suffering from fibromyalgia: a randomized double-blind controlled study

Introduction

Fibromyalgia is characterized by widespread and chronic pain, and its prevalence is increasing worldwide. Milnacipran, an antidepressant, is often prescribed for fibromyalgia with a possible beneficial effect on central pain modulation. The aim of this study was to evaluate if milnacipran could modify the status of conditioned pain modulation (CPM) in patients suffering from fibromyalgia.

Design and setting

Randomized, double-blind controlled trial.

Subjects and methods

Women with fibromyalgia received milnacipran 100 mg or placebo. The primary end point was the evolution of CPM with treatments after a 30-second painful stimulus. Secondary outcomes included the predictability of milnacipran efficacy from CPM performance, evolution of global pain, mechanical sensitivity, thermal pain threshold, mechanical allodynia, cognitive function, and tolerance.

Results

Fifty-four women with fibromyalgia (46.7±10.6 years) were included and randomized, and 24 patients were analyzed in each group. At inclusion, CPM was dysfunctional (CPM₃₀=-0.5±1.9), and global pain was 6.5±1.8. After treatment, there was a nonsignificant CPM difference between milnacipran and placebo (CPM₃₀=-0.46±1.22 vs -0.69±1.43, respectively, p=0.55) and 18.8% vs 6.3% (p=0.085) patients did reactivate CPM after milnacipran vs placebo. Initial CPM was not a predictor of milnacipran efficacy. Global pain, mechanical and thermal thresholds, allodynia, cognition, and tolerance were not significantly different between both groups.

Conclusion

Milnacipran did not display a significant analgesic effect after 1-month treatment, but the tendency of milnacipran to reactivate CPM in a number of patients must be explored with longer treatment duration in future studies and pleads for possible subtypes of fibromyalgia patients.

Primary Headache Disorders- Part 2: Tension-type headache and medication overuse headache

In Part 2 of Primary Headache disorders, we discuss the fourth Primary Headache Disorder, Tension-Type Headache (TTHA). We are again using the ICHD-III (Beta) definitions of such headaches, taking into consideration episodic and chronic TTHA, as well as the presence or absence of pericranial muscle tenderness. We discuss the pathophysiology and pharmacotherapeutic treatment of TTHA, and the aspects of the Myofascial Pain Syndrome that enhance and help the development of TTHA. We then discuss Medication Overuse Headache (MOH), itself a Secondary headache disorder, but one that is extremely important as it assists with the chronification of both migraine and TTHA. Finally we discuss how to manage and treat those patients with MOH. Chronic migraine, which is TTHA, Migraine as well as, in many patients, MOH, is discussed along with the treatment of this multifaceted disorder.

The effects of local cold application on fibromyalgia pain

AIM

This study was conducted to evaluate the effects of local cold application on pain when applied to the trapezius muscles of patients with fibromyalgia.

METHOD

A one-group, pre-test/post-test, pre-experimental model was applied in this study, which was conducted with 55 fibromyalgia patients who presented to a rheumatology outpatient clinic. A 10-min cold application was administered to one trapezius muscle of each patient. The participants' pain was evaluated, in total, four times (before the cold application and 10 min, 1.5 h and 24 h after the cold application). The visual analogue scale (VAS) for pain was used to collect data for the study, and Friedman and Wilcoxon tests were used to assess the data.

RESULTS

The patients' pain mean score before (6.45, SD:1.27) the cold applications was found to be significantly higher than the scores noted 10 min (2.75, SD:1.73), 1.5 h (2.45, SD:1.29), and 24 h (3.36, SD:1.30) after the application (P < 0.001).

CONCLUSION

The study found that local cold applications performed on the trapezius muscles of patients with fibromyalgia significantly decreased their pain. With its discovery of a new method of pain control in fibromyalgia patients, this study will significantly contribute to science and will serve as a guide for pain management, especially in nursing practice. Further studies to evaluate the maximum effect duration and effect mechanisms of local cold applications to the trapezius muscles of FM patients are indicated.

Rethinking chronic pain in a primary care setting

Chronic pain substantially impacts patient function and quality of life and is a burden to society at large in terms of increased health care utilization and loss of productivity. As a result, there is an increasing recognition of chronic pain as a public health crisis. However, there remains wide variability in clinical practices related to the prevention, assessment, and treatment of chronic pain. Certain fundamental aspects of chronic pain are often neglected including the contribution of the psychological, social, and contextual factors associated with chronic pain. Also commonly overlooked is the importance of understanding the likely neurobiological mechanism(s) of the presenting pain and how they can guide treatment selection. Finally, physicians may not recognize the value of using electronic medical records to systematically capture data on pain and its impact on mood, function, and sleep. Such data can be used to monitor onset and maintenance of treatments effects at the patient level and evaluate costs at the systems level. In this review we explain how these factors play a critical role in the development of a coordinated, evidence-based treatment approach tailored to meet specific needs of the patient. We also discuss some practical approaches and techniques that can be implemented by clinicians in order to enhance the assessment and management of individuals with chronic pain in primary care settings.

Poor Illness Perceptions Are a Risk Factor for Depressive and Anxious Symptomatology in Fibromyalgia Syndrome: A Longitudinal Cohort Study

BACKGROUND

Patients with widespread pain, such as in fibromyalgia, are vulnerable for depression and anxiety, which composes a relevant public health problem. Identifying risk factors for the onset of depression and anxiety is therefore warranted. Objective of this study was to determine whether severe pain, maladaptive coping, and poor illness perceptions are associated with depressive and anxious symptomatology in fibromyalgia.

METHOD

Consecutive patients referred to an outpatient clinic completed sets of physical and psychological questionnaires at baseline and at 18-month follow-up. A total of 452 patients with fibromyalgia syndrome (FMS) were eligible for inclusion, and subsequently, 280 patients returned the baseline questionnaire. Depressive and anxious symptomatology was measured with the Hospital Anxiety and Depression Scale. To measure pain severity, coping style, and illness perceptions, the Fibromyalgia Impact Questionnaire, Pain Coping Inventory, and the Illness Perception Questionnaire-Revised (IPQ-R) were used, respectively. Multivariable logistic regression analyses, bootstrapping and calibration, were performed to examine the association of pain severity, pain coping, and illness perception with depressive and anxiety symptoms at follow-up, adjusted for sociodemographic variables. Initial level of depressive and anxiety symptoms was selected as covariates.

RESULTS

Mean age was 42.6 years and 95.4% were female. At 18-month follow-up, 68 (of the 195) patients were depressed and 80 (of the 197) were anxious. Only the IPQ-R subscale "emotional representations" showed a significant positive association with depressive symptoms at follow-up (OR = 1.10), next to the initial level of depressive symptoms (OR = 1.30). In case of anxiety, only the IPQ-R subscale "treatment control" showed a significant negative association with anxiety symptoms at follow-up (OR = 0.87), next to the initial level of anxiety symptoms (OR = 1.45).

CONCLUSION

Our data suggest that not pain severity or maladaptive coping, but poor illness perceptions are important in elevated depressive and anxious symptomatology. Patients with fibromyalgia who think their illness negatively affects their mental well-being are at increased risk for more depressive symptoms, and those who think treatment of their illness will not be effective are at increased risk for more anxiety symptoms. Strengthening illness beliefs and reducing catastrophic thinking, therefore, seem crucial factors in the treatment of patients with FMS.

Gray matter abnormalities associated with fibromyalgia: A meta-analysis of voxel-based morphometric studies

OBJECTIVES

Studies employing voxel-based morphometry (VBM) have reported inconsistent findings on the association of gray matter (GM) abnormalities with fibromyalgia. The aim of the present study is to identify the most prominent and replicable GM areas that involved in fibromyalgia.

METHODS

A systematic search of the PubMed database from January 2000 to September 2015 was performed to identify eligible whole-brain VBM studies. Comprehensive meta-analyses to investigate regional GM abnormalities in fibromyalgia were conducted with the Seed-based d Mapping software package.

RESULTS

Seven studies, reporting nine comparisons and including a grand total of 180 fibromyalgia patients and 126 healthy controls, were included in the meta-analyses. In fibromyalgia patients compared with healthy controls, regional GM decreases were consistently found in the bilateral anterior cingulate/paracingulate cortex/medial prefrontal cortex, the bilateral posterior cingulate/paracingulate cortex, the left parahippocampal gyrus/fusiform cortex, and the right parahippocampal gyrus/hippocampus. Regional GM increases were consistently found in the left cerebellum. Meta-regression demonstrated that age was correlated with GM anomalies in fibromyalgia patients.

CONCLUSIONS

The current meta-analysis identified a characteristic pattern of GM alterations within the medial pain system, default mode network, and cerebro-cerebellar circuits, which further supports the concept that fibromyalgia is a symptom complex involving brain areas beyond those implicated in chronic pain.