Genetic polymorphisms of the beta2-adrenergic receptor relate to guanosine protein-coupled stimulator receptor dysfunction in fibromyalgia syndrome

A Comprehensive Review of the Genetic and Epigenetic Contributions to the Development of Fibromyalgia

This narrative review summarizes the current knowledge of the genetic and epigenetic contributions to the development of fibromyalgia (FM). Although there is no single gene that results in the development of FM, this study reveals that certain polymorphisms in genes involved in the catecholaminergic pathway, the serotonergic pathway, pain processing, oxidative stress, and inflammation may influence susceptibility to FM and the severity of its symptoms. Furthermore, epigenetic changes at the DNA level may lead to the development of FM. Likewise, microRNAs may impact the expression of certain proteins that lead to the worsening of FM-associated symptoms.

AKAP12 and RNF11 as Diagnostic Markers of Fibromyalgia and Their Correlation with Immune Infiltration

Fibromyalgia (FM) is a chronic nonarticular rheumatic disease mainly characterized by diffuse disseminated skeletal muscle pain, with varied symptoms including anxiety, sleep disturbance, and fatigue. Due to its unknown etiology and pathogenesis, FM is easily ignored in clinical practice, resulting in unclear diagnosis and difficult treatment. This study is aimed at investigating whether AKAP12 and RNF11 can be used as biomarkers for the diagnosis of FM and at determining their correlation with immune infiltration. The FM dataset in Gene Expression Omnibus (GEO) database was downloaded and was randomly divided into the training and test sets. Differentially expressed genes (DEGs) were screened, and functional correlation analysis was performed. Diagnostic markers of FM were screened and validated by random forest (RF). The least absolute shrinkage and selection operator (LASSO) logistic regression algorithm was then used to evaluate immune cell infiltration in the FM patients' peripheral blood. Finally, Spearman's rank correlation analysis was used to identify correlation between the diagnostic indexes and immune cell infiltration. A total of 69 DEGs were selected. Results indicated that AKAP12 and RNF11 can be used as diagnostic markers of FM, and CD8 + T cells might contribute in the pathogenesis of FM. In addition, AKAP12 was positively correlated with CD8 + T cells, while RNF11 was negatively correlated with CD8 + T cells. In conclusion, AKAP12 and RNF11 can be used as diagnostic indicators of FM, and CD8 + T cells may be involved in the occurrence and development of FM.

The evaluation of nailfold capillaroscopy pattern in patients with fibromyalgia

Objectives

This study aims to evaluate nailfold capillaroscopic pattern in patents with fibromyalgia and to assess the relation of capillaroscopic parameters with clinical variables and disease-related measures.

Patients and methods

This cross-sectional, case-control study included 60 participants (4 males, 56 females; mean age: 44.0±8.2 years; range, 26 to 64 years) between August 2019 and November 2019. All participants were divided into two groups as the primary fibromyalgia group (n=30) who met the 2016 modified American College of Rheumatology Diagnostic Criteria for Fibromyalgia and the control group (n=30) consisting of age- and sex-matched healthy individuals. Nailfold capillaroscopy was performed by a digital microscope under a magnification of 200X. Capillary density, capillary loop diameter, number of dilated, giant and neoangiogenic capillaries, capillary shape, number of avascular areas, micro-aneurysms and micro-hemorrhages were evaluated by an assessor who was blind to the group allocation. In the fibromyalgia group, Widespread Pain Index, Symptom Severity Scale scores, and Fibromyalgia Severity scores were calculated. Health status and presence of benign joint hypermobility syndrome (BJHS) were evaluated using the Fibromyalgia Impact Questionnaire (FIQ) and revised Brighton criteria, respectively.

Results

Of the capillaroscopic parameters, the mean capillary loop diameter, number of micro-aneurysms, avascular areas, and neoangiogenic capillaries were significantly higher in the patient group compared to the controls (p<0.001, p=0.016, p=0.038, and p=0.04, respectively). Nailfold capillaroscopic findings did not significantly differ between the patients with (n=16) and without concomitant BJHS (n=14). Of the disease-related measures, only FIQ score showed a weak correlation with the number of dilated capillaries (p=0.324).

Conclusion

Patients with fibromyalgia have distinct capillaroscopic patterns than healthy population. Capillaroscopic features, in general, are not related to clinical variables and disease-related measures.

Fibromyalgia: A Review of Related Polymorphisms and Clinical Relevance

Fibromyalgia (FM) is a chronic pain syndrome that affects the central nervous system and generates disability, which is characterized by generalized pain, fatigue, and functional decline. In this review, we aimed to identify the polymorphisms related to the pathophysiology of FM and the clinical characteristics generated by genetic influence. Only original studies with genes related to FM were considered, totaling 27 articles. The genes found were: MTHFR, RGS4, MYT1L, TACR1, SCN9A, DRD3, ADRB2, IL-4, HLA-DRB1, EDN1, CNR1, TAAR1, OPRM1, ADRA1A, ADRB3, BDNF, GRIA4, HTR3A, HTR3B, HTR2A, SERPINA 1 or A1AT, NRXN3, GCH1, MEFV, TRPV3, SLC6A4, ACE I/D, TSPO, COMT, and MAOA. Several genes related to different pain syndromes and altered pain thresholds have been identified and some polymorphisms were related to susceptibility to FM. It was observed that 73.33% of the genes related to FM were also associated with some psychological disorders, such as anxiety, depression, schizophrenia, and obsessive and compulsive disorder, and 40.00% with pain sensitivity and/or migraine, besides other disorders associated (drug addiction, autoimmune disorders, circulatory problems, and metabolic alterations). This review demonstrated an association of FM and genetic polymorphisms that can expand our knowledge about the pathophysiology of this disease.

Abdominal pain in patients with inflammatory bowel disease: association with single-nucleotide polymorphisms prevalent in irritable bowel syndrome and clinical management

BACKGROUND

Abdominal pain is a frequent symptom in patients with inflammatory bowel disease (IBD) including Crohn's disease (CD) and ulcerative colitis (UC). Pain can result from ongoing inflammation or functional disorders imitating irritable bowel syndrome (IBS). Several single-nucleotide polymorphisms (SNPs) have been associated with IBS. However, the impact of IBS genetics on the clinical course of IBD, especially pain levels of patients remains unclear.

METHODS

Data of 857 UC and 1206 CD patients from the Swiss IBD Cohort Study were analysed. We tested the association of the maximum of the abdominal pain item of disease activity indices in UC and CD over the study period with 16 IBS-associated SNPs, using multivariate ANOVA models.

RESULTS

In UC patients, the SNPs rs1042713 (located on the ADRB2 gene) and rs4663866 (close to the HES6 gene) were associated with higher abdominal pain levels (P = 0.044; P = 0.037, respectively). Abdominal pain was not associated with any markers of patient management in a model adjusted for confounders. In CD patients, higher levels of abdominal pain correlated with the number of physician contacts (P < 10^-15), examinations (P < 10^-12), medical therapies (P = 0.023) and weeks of hospitalisation (P = 0.0013) in a multivariate model.

CONCLUSIONS

We detected an association between maximal abdominal pain in UC patients and two IBS-associated SNPs. Abdominal pain levels had a pronounced impact on diagnostic and therapeutic procedures in CD but not in UC patients.

Exploratory study into the relationship between the symptoms of chronic fatigue syndrome (CFS)/myalgic encephalomyelitis (ME) and fibromyalgia (FM) using a quasiexperimental design

OBJECTIVE

To explore the relationship between symptoms of chronic fatigue syndrome (CFS)/myalgic encephalomyelitis (ME) and fibromyalgia (FM). The hypothesis predicated that there would be no significant differences between the group's symptom experience.

DESIGN

A quasiexperimental design. Structural equation modelling (SEM) and invariance testing.

PARTICIPANTS

Males (M) and females (F) >16 with a confirmed diagnosis of CFS/ME or FM by a general practitioner or specialist. CFS/ME (n=101, F: n=86, M: n=15, mean (M) age M=45.5 years). FM (n=107, F: n=95, M: n=12, M=47.2 years).

OUTCOME MEASURES

Diagnostic criteria: the American Centers for Disease Control and Prevention (CDC) for CFS/ME and the American College of Rheumatology (ACR) criteria for FM. Additional symptom questionnaires measuring: pain, sleep quality, fatigue, quality of life, anxiety and depression, locus of control and self-esteem.

RESULTS

Invariance was confirmed with the exception of the American CDC Symptom Inventory, Fibromyalgia Impact Questionnaire and Hospital Anxiety and Depression Scale (p<0.05) based on five questions. Consequently, it was erroneous to conclude differences. Therefore, the Syndrome Model was created. SEM could not have tested the ACR previously, as it comprised a single data point. Thus, it was combined with these three questionnaires, increasing the data points, to create this new measurable model. Results confirmed no significant differences between groups (p=0.07 (p<0.05)).

CONCLUSION

Participants responded in a similar manner to the questionnaire, confirming the same symptom experience. It is important to consider this in context with differing criteria and management guidelines, as this may influence diagnosis and the trajectory of patient's management. With the biomedical cause currently unclear, it is the symptom experience and the impact on quality of life that is important. These findings are meaningful for patients, clinicians and policy development and support the requirement for future research.

Comparison of Beta-2 Adrenergic Receptor Gene Polymorphisms Between Patients with Fibromyalgia Syndrome and Healthy Controls

Objectives

This study aims to compare the beta-2 adrenergic receptor (ADRB2) gene polymorphisms of patients with fibromyalgia syndrome (FMS) with those of healthy control subjects, and to investigate the possible relationship between symptoms of FMS and polymorphisms of the ADRB2 gene.

Patients and methods

The study included 170 females (mean age 47.8±10.3 years; range, 21 to 75 years) diagnosed with FMS according to the 2010 American College of Rheumatology criteria and 170 healthy females (mean age 47.2±8.8 years; range, 20 to 72 years) as the control group. Several clinical symptoms of the participants related to FMS were questioned and recorded. The visual analog scale (VAS) and Fibromyalgia Impact Questionnaire (FIQ) scores of the fibromyalgia group were recorded. In both groups, the ADRB2 (rs1042717) single-nucleotide polymorphism was detected by way of a real-time polymerase chain reaction. The wild-type (Guanine/Guanine), the mutant type (Adenine/Adenine) and heterozygous type (Adenine/Guanine) were detected. The sample power was calculated considering the minor allele frequency.

Results

The comparison of the ADRB2 gene polymorphism between patients with FMS and the control subjects showed that the groups were similar in terms of ADBR2 gene polymorphism and genotype (p>0.05). There was no significant difference in terms of genotype when the ADRB2 gene polymorphisms in patients with FMS were compared in terms of clinical symptoms, VAS and FIQ scores (p>0.05).

Conclusion

Beta-2 adrenergic receptor (rs1042717) gene polymorphisms and genotype distribution are no different between patients with FMS and healthy individuals. ADRB2 gene polymorphisms in patients with FMS have no effect on clinical symptoms and VAS and FIQ scores. The results of the present study will light the way for future research into ADRB2 gene polymorphisms in the pathogenesis of FMS.

Pain catastrophizing is associated with the Val66Met polymorphism of the brain-derived neurotrophic factor in fibromyalgia

BACKGROUND

Fibromyalgia (FM) is a musculoskeletal chronic pain syndrome that impacts negatively patient's daily lives. Its pathogenesis is characterized by a complex relationship between biological and psychosocial factors not fully understood yet. Pain catastrophizing is associated with FM and is an important predictor of outcomes. This study aimed to answer two questions: (i) whether the allele and genotype frequencies of BDNF Val66Met (rs6265) polymorphism differs between FM patients and healthy controls (HC); and (ii) if the BDNF Val66Met polymorphism is a factor that predicts pain catastrophizing in FM.

METHODS

In a cross-sectional design, 108 FM patients and 108 HC were included. FM patients responded to the Brazilian Portuguese version of the Pain Catastrophizing Scale (BP-PCS) to assess pain catastrophizing, as well as other validated tools for anxiety (The State-Trait Anxiety Inventory - STAI), depression (Beck Depression Inventory II - BDI-II) and functional aspects (Fibromyalgia Impact Questionnaire - FIQ; Central Sensitization Inventory validated and adapted for Brazilian population - CSI-BP; Pittsburgh Sleep Quality Index - PSQI; and Resilience Scale). All subjects were genotyped for the BDNF Val66Met polymorphism.

RESULTS

Val allele was significantly more frequent in FM patients compared to the control group (p < 0.05). Also, FM patients with Val/Val genotype showed more pain catastrophizing thoughts, and this genotype was significantly associated with magnification and rumination dimensions of BP-PCS (p < 0.05). Furthermore, there were significant differences in levels of anxiety and symptoms of depression, years of education, and the functional situation between the FM and control groups.

CONCLUSIONS

The findings show an association of BDNF Val66Met polymorphism with pain catastrophizing in FM, which opens new avenues to comprehend the interplay between molecular genetic characteristics and neuroplasticity mechanisms underpinning FM.

Dysfunctional stress responses in chronic pain

Many dysfunctional and chronic pain conditions overlap. This review describes the different modes of chronic deregulation of the adaptive response to stress which may be a common factor for these conditions. Several types of dysfunction can be identified within the hypothalamo-pituitary-adrenal axis: basal hypercortisolism, hyper-reactivity, basal hypocortisolism and hypo-reactivity. Neuroactive steroid synthesis is another component of the adaptive response to stress. Dehydroepiandrosterone (DHEA) and its sulfated form DHEA-S, and progesterone and its derivatives are synthetized in cutaneous, nervous, and adipose cells. They are neuroactive factors that act locally. They may have a role in the localization of the symptoms and their levels can vary both in the central nervous system and in the periphery. Persistent changes in neuroactive steroid levels or precursors can induce localized neurodegeneration. The autonomic nervous system is another component of the stress response. Its dysfunction in chronic stress responses can be expressed by decreased basal parasympathethic activity, increased basal sympathetic activity or sympathetic hyporeactivity to a stressful stimulus. The immune and genetic systems also participate. The helper-T cells Th1 secrete pro-inflammatory cytokines such as IL-1-β, IL-2, IL-6, IL-8, IL-12, IFN-γ, and TNF-α, whereas Th2 secrete anti-inflammatory cytokines: IL-4, IL-10, IGF-10, IL-13. Chronic deregulation of the Th1/Th2 balance can occur in favor of anti- or pro-inflammatory direction, locally or systemically. Individual vulnerability to stress can be due to environmental factors but can also be genetically influenced. Genetic polymorphisms and epigenetics are the main keys to understanding the influence of genetics on the response of individuals to constraints.

Fibromyalgia: A Critical and Comprehensive Review

Fibromyalgia is a disorder that is part of a spectrum of syndromes that lack precise classification. It is often considered as part of the global overview of functional somatic syndromes that are otherwise medically unexplained or part of a somatization disorder. Patients with fibromyalgia share symptoms with other functional somatic problems, including issues of myalgias, arthralgias, fatigue and sleep disturbances. Indeed, there is often diagnostic and classification overlap for the case definitions of a variety of somatization disorders. Fibromyalgia, however, is a critically important syndrome for physicians and scientists to be aware of. Patients should be taken very seriously and provided optimal care. Although inflammatory, infectious, and autoimmune disorders have all been ascribed to be etiological events in the development of fibromyalgia, there is very little data to support such a thesis. Many of these disorders are associated with depression and anxiety and may even be part of what has been sometimes called affected spectrum disorders. There is no evidence that physical trauma, i.e., automobile accidents, is associated with the development or exacerbation of fibromyalgia. Treatment should be placed on education, patient support, physical therapy, nutrition, and exercise, including the use of drugs that are approved for the treatment of fibromyalgia. Treatment should not include opiates and patients should not become poly pharmacies in which the treatment itself can lead to significant morbidities. Patients with fibromyalgia are living and not dying of this disorder and positive outlooks and family support are key elements in the management of patients.

Programmed symptoms: disparate effects united by purpose

Central sensitivity syndromes (CSS) share features of similar multiple symptoms, virtually unknown mechanisms and lack of effective treatments. The CSS nomenclature was chosen over alternatives because it focused on a putative physiological mechanism of central sensitization common to disorders such as fibromyalgia, irritable bowel syndrome, vulvodynia and temporomandibular disorder. Increasing evidence from multiple biological systems suggests a further development. In this new model central sensitization is part of a ensemble that includes also the symptoms of widespread pain, fatigue, unrefreshing sleep and dyscognition. The main feature is an intrinsic program that produces this ensemble to guide behavior to restore normal function in conditions that threaten survival. The well known “illness response” is a classic example that is triggered in response to the specific threat of viral infection. The major leap for this model in the context of CSS is that the symptom complex is not a reactive result of pathology, but a purposeful feeling state enlisted to combat pathology. Once triggered, this state is produced by potential mechanisms that likely include contributions of the peripheral and central immune systems, as well as stress response systems such as the autonomic system and the hypothalamic–pituitary–adrenal (HPA) axis. These act in concert to alter behavior in a beneficial direction. This concept explains similar symptoms for many triggering conditions, the poorly understood pathology, and the resistance to treatment.

Update on the genetics of the fibromyalgia syndrome

Fibromyalgia syndrome (FMS), a condition characterized by chronic widespread pain and tenderness, is a complex condition considered to represent a paradigm of centralized pain. FMS has demonstrated a clear familial aggregation, and hence it is considered to have a genetic background. Multiple candidate-gene studies have been conducted in this field, focusing on target genes that play a role in the transmission and processing of pain. While many of these have focused in the past on markers related to neurotransmitter systems such as catecholamines (catechol-O-methyltransferase (COMT)) and serotonin, novel target genes have recently emerged. In addition, genome-wide sequencing scanning (genome-wide association study (GWAS)) is increasingly being harnessed for the study of chronic pain, including FMS. Micro RNAs are another novel field of research related to posttranscriptional inhibition of gene expression, which are currently regarding the pathogenesis of FMS.

Genetic variants associated with development of TMD and its intermediate phenotypes: the genetic architecture of TMD in the OPPERA prospective cohort study

Genetic risk factors are believed to combine with environmental exposures and contribute to the risk of developing temporomandibular disorder (TMD). In this prospective cohort study, 2,737 people without TMD were assessed for common genetic variation in 358 genes known to contribute to nociceptive pathways, inflammation, and affective distress. During a median follow-up period of 2.8 years, 260 people developed first-onset TMD. Hazard ratios were computed as measures of association between 2,924 single-nucleotide polymorphisms and TMD incidence. After correction for multiple testing, no single single-nucleotide polymorphism was significantly associated with risk of onset TMD. However, several single-nucleotide polymorphisms exceeded Bonferroni correction for multiple comparison or false discovery rate thresholds (.05, .1, or .2) for association with intermediate phenotypes shown to be predictive of TMD onset. Nonspecific orofacial symptoms were associated with voltage-gated sodium channel, type I, alpha subunit (SCN1A, rs6432860, P = 2.77 × 10(-5)) and angiotensin I-converting enzyme 2 (ACE2, rs1514280, P = 4.86 × 10(-5)); global psychological symptoms with prostaglandin-endoperoxide synthase 1 (PTGS1, rs3842803, P = 2.79 × 10(-6)); stress and negative affectivity with amyloid-β (A4) precursor protein (APP, rs466448, P = 4.29 × 10(-5)); and heat pain temporal summation with multiple PDZ domain protein (MPDZ, rs10809907, P = 3.05 × 10(-5)). The use of intermediate phenotypes for complex pain diseases revealed new genetic pathways influencing risk of TMD.

PERSPECTIVE

This article reports the findings of a large candidate gene association study of first-onset TMD and related intermediate phenotypes in the OPPERA Study. Although no genetic markers predicted TMD onset, several genetic risk factors for clinical, psychological, and sensory phenotypes associated with TMD onset were observed.

Management of fibromyalgia syndrome: review of evidence

Fibromyalgia syndrome (FMS) is a common chronic musculoskeletal pain disorder of unknown etiology and characterized by generalized body pain, hyperalgesia, and other functional and emotional comorbidities. Despite extensive research, no treatment modality is effective for all FMS patients. In this paper, we briefly review the history of FMS and diagnostic criteria, and potential pathophysiological mechanisms including central pain modulation, neurotransmitters, sympatho-adrenal and hypothalamic–pituitary–adrenal systems and peripheral muscle issues. The primary focus of the paper is to review treatment options for managing fibromyalgia symptoms. We will discuss FDA-approved medications and other pharmacologic agents, and non-pharmacologic treatments that have shown promising effects.

The phenotypic and genetic signatures of common musculoskeletal pain conditions

Musculoskeletal pain conditions, such as fibromyalgia and low back pain, tend to coexist in affected individuals and are characterized by a report of pain greater than expected based on the results of a standard physical evaluation. The pathophysiology of these conditions is largely unknown, we lack biological markers for accurate diagnosis, and conventional therapeutics have limited effectiveness. Growing evidence suggests that chronic pain conditions are associated with both physical and psychological triggers, which initiate pain amplification and psychological distress; thus, susceptibility is dictated by complex interactions between genetic and environmental factors. Herein, we review phenotypic and genetic markers of common musculoskeletal pain conditions, selected based on their association with musculoskeletal pain in previous research. The phenotypic markers of greatest interest include measures of pain amplification and 'psychological' measures (such as emotional distress, somatic awareness, psychosocial stress and catastrophizing). Genetic polymorphisms reproducibly linked with musculoskeletal pain are found in genes contributing to serotonergic and adrenergic pathways. Elucidation of the biological mechanisms by which these markers contribute to the perception of pain in these patients will enable the development of novel effective drugs and methodologies that permit better diagnoses and approaches to personalized medicine.

Effect of experimental stress in 2 different pain conditions affecting the facial muscles

Chronic facial muscle pain is a common feature in both fibromyalgia (FM) and myofascial (MF) pain conditions. In this controlled study, a possible difference in the mode of deregulation of the physiological response to a stressing stimulus was explored by applying an acute mental stress to FM and MF patients and to controls. The effects of the stress test were observed on pain, sympathetic variables, and both tonic and reflex electromyographic activities of masseteric and temporal muscles. The statistical analyses were performed through a generalized linear model including mixed effects. Painful reaction to the stressor was stronger (P < .001) and longer (P = .011) in FM than in MF independently of a higher pain level at baseline. The stress-induced autonomic changes only seen in FM patients did not reach significance. The electromyographic responses to the stress test were strongest for controls and weakest for FM. The stress test had no effect on reflex activity (area under the curve [AUC]) or latency, although AUC was high in FM and latencies were low in both pain groups. It is suggested that FM is characterized by a lower ability to adapt to acute stress than MF.

PERSPECTIVE

This study showed that an acute psychosocial stress triggered several changes in 2 pain conditions including an increase in pain of larger amplitude in FM than in MF pain. Similar stress-induced changes should be explored as possible mechanisms for differentiation between dysfunctional pain conditions.

Obesity is a risk factor for musculoskeletal pain in adolescents: findings from a population-based cohort

Obesity is a risk factor for fibromyalgia in adults, but whether a similar relationship exists in children is uncertain. This study examined whether obesity is associated with reporting of musculoskeletal pain, including chronic regional pain (CRP) and chronic widespread pain (CWP), in adolescents, in a population-based setting. A pain questionnaire was administered to offspring of the Avon Longitudinal Study of Parents and Children at age 17, asking about site, duration, and pain intensity, from which participants with different types of musculoskeletal pain were identified. Relationships between obesity and pain were examined by calculating odds ratios stratified by gender and adjusted for socioeconomic status as reflected by level of maternal education. A total of 3376 participants (1424 boys) with complete data were identified, mean age 17.8; 44.7% of participants reported any pain within the last month lasting 1day or longer; 16.3% reported lower back pain, 9.6% shoulder pain, 9.4% upper back pain, 8.9% neck pain, 8.7% knee pain, 6.8% ankle/foot pain, 4.7% CRP, and 4.3% CWP; 7.0% of participants were obese. Obesity was associated with increased odds of any pain (odds ratio [OR] 1.33, P=.04), CRP (OR 2.04, P=.005), and knee pain (OR 1.87, P=.001), but not CWP (OR 1.10, P=.5). Compared with non obese participants, those with any pain, knee pain, and CRP reported more severe average pain (P<.01). Obese adolescents were more likely to report musculoskeletal pain, including knee pain and CRP. Moreover, obese adolescents with knee pain and CRP had relatively high pain scores, suggesting a more severe phenotype with worse prognosis.

Fibromyalgia: a primer for the anesthesia community

PURPOSE OF REVIEW

The present review is intended to give an overview of fibromyalgia for the anesthesiologist. While the basics of the treatment of fibromyalgia are included, the intent is to provide context to discuss the potential implications in perioperative management.

RECENT FINDINGS

Research continues to demonstrate that fibromyalgia patients have neurophysiologic abnormalities that alter sensory perception, including lower levels of central neurotransmitters associated with the inhibition of pain and higher levels those that facilitate pain. While comorbid mood disorders are more common in fibromyalgia patients, studies have shown that fibromyalgia symptoms are not explained by depression alone. In the last year, the American College of Rheumatology established a new self-report questionnaire for the diagnosis of fibromyalgia in lieu of the previously required tender point examination plus self-report questionnaire. This questionnaire allows for the study of the severity of sensitivity and symptomatology on a continuum, which is termed 'fibromyalgianess'. Some new concepts in the treatment have been proposed, including sodium oxybate, transcranial magnetic stimulation, and web-based cognitive behavioral therapy.

SUMMARY

The impact of fibromyalgia on anesthesia care is not known. Years of quality research have clearly demonstrated multiple pathophysiologic changes that could impact anesthesia care and future study is needed.

Genetics and Gene Expression Involving Stress and Distress Pathways in Fibromyalgia with and without Comorbid Chronic Fatigue Syndrome

In complex multisymptom disorders like fibromyalgia syndrome (FMS) and chronic fatigue syndrome (CFS) that are defined primarily by subjective symptoms, genetic and gene expression profiles can provide very useful objective information. This paper summarizes research on genes that may be linked to increased susceptibility in developing and maintaining these disorders, and research on resting and stressor-evoked changes in leukocyte gene expression, highlighting physiological pathways linked to stress and distress. These include the adrenergic nervous system, the hypothalamic-pituitary-adrenal axis and serotonergic pathways, and exercise responsive metabolite-detecting ion channels. The findings to date provide some support for both inherited susceptibility and/or physiological dysregulation in all three systems, particularly for catechol-O-methyl transferase (COMT) genes, the glucocorticoid and the related mineralocorticoid receptors (NR3C1, NR3C2), and the purinergic 2X4 (P2X4) ion channel involved as a sensory receptor for muscle pain and fatigue and also in upregulation of spinal microglia in chronic pain models. Methodological concerns for future research, including potential influences of comorbid clinical depression and antidepressants and other medications, on gene expression are also addressed.