Fibromyalgia, chronic fatigue syndrome, and myofascial pain syndrome

Unbiased immune profiling reveals a natural killer cell-peripheral nerve axis in fibromyalgia

ABSTRACT

The pathophysiology of fibromyalgia syndrome (FMS) remains elusive, leading to a lack of objective diagnostic criteria and targeted treatment. We globally evaluated immune system changes in FMS by conducting multiparametric flow cytometry analyses of peripheral blood mononuclear cells and identified a natural killer (NK) cell decrease in patients with FMS. Circulating NK cells in FMS were exhausted yet activated, evidenced by lower surface expression of CD16, CD96, and CD226 and more CD107a and TIGIT. These NK cells were hyperresponsive, with increased CCL4 production and expression of CD107a when co-cultured with human leukocyte antigen null target cells. Genetic and transcriptomic pathway analyses identified significant enrichment of cell activation pathways in FMS driven by NK cells. Skin biopsies showed increased expression of NK activation ligand, unique long 16-binding protein, on subepidermal nerves of patients FMS and the presence of NK cells near peripheral nerves. Collectively, our results suggest that chronic activation and redistribution of circulating NK cells to the peripheral nerves contribute to the immunopathology associated with FMS.

Brainstem damage is associated with poorer sleep quality and increased pain in gulf war illness veterans

AIMS

Gulf War Illness (GWI) is manifested as multiple chronic symptoms, including chronic pain, chronic fatigue, sleep problems, neuropsychiatric disorders, respiratory, gastrointestinal, and skin problems. No single target tissue or unifying pathogenic process has been identified that accounts for this variety of symptoms. The brainstem has been suspected to contribute to this multiple symptomatology. The aim of this study was to assess the role of the brainstem in chronic sleep problems and pain in GWI veterans.

MATERIALS AND METHODS

We enrolled 90 veterans (Age = 50 ± 5, 87% Male) who were deployed to the 1990-91 Gulf War and presented with GWI symptoms. Sleep quality was evaluated using the global Pittsburgh Sleep Quality Index. Pain intensities were obtained with the Brief Pain Inventory sum score. Volumes in cortical, subcortical, brainstem, and brainstem subregions and diffusion tensor metrics in 10 bilateral brainstem tracts were tested for correlations with symptom measures.

KEY FINDINGS

Poorer sleep quality was significantly correlated with atrophy of the whole brainstem and brainstem subregions (including midbrain, pons, medulla). Poorer sleep quality also significantly correlated with lower fractional anisotropy in the nigrostriatal tract, medial forebrain tract, and the dorsal longitudinal fasciculus. There was a significant correlation between increased pain intensity and decreased fractional anisotropy in the dorsal longitudinal fasciculus. These correlations were not altered after controlling for age, sex, total intracranial volumes, or additional factors, e.g., depression and neurological conditions.

SIGNIFICANCE

These findings suggest that the brainstem plays an important role in the aberrant neuromodulation of sleep and pain symptoms in GWI.

Investigation of thermal changes in the thyroid gland region of individuals with hypothyroidism and fibromyalgia by analyzing the temperature of brown adipose tissue

This exploratory retrospective study aims to investigate the thermal changes in the thyroid gland region of patients with hypothyroidism and fibromyalgia by analyzing the temperature of the brown adipose tissue (BAT). A total of 166 individuals from 1000 thermographic electronic medical records were classified into four groups: Group HP + FM-50 individuals with hypothyroidism and fibromyalgia; Group FM-56 individuals with fibromyalgia only; Group HP-30 individuals with hypothyroidism only, and Group Control-30 healthy individuals. The thermal images from the electronic medical records were acquired by a FLIR T650SC infrared camera (used for thermometry) and the temperature data for each group were statistically analyzed. Group HP + FM showed r = 0, meaning that the average temperatures of the thyroid and BAT are independent of each other. Groups FM, HP and Control showed r = 1, meaning that the average temperatures of the thyroid and BAT were directly related. Our findings showed that the average temperatures of the thyroid and BAT regions are similar. Also, there was no correlation between thyroid gland temperature and the presence of hypothyroidism or fibromyalgia using thermometry.

Mycoplasmas-Host Interaction: Mechanisms of Inflammation and Association with Cellular Transformation

Mycoplasmas are the smallest and simplest self-replicating prokaryotes. Located everywhere in nature, they are widespread as parasites of humans, mammals, reptiles, fish, arthropods, and plants. They usually exhibiting organ and tissue specificity. Mycoplasmas belong to the class named Mollicutes (mollis = soft and cutis = skin, in Latin), and their small size and absence of a cell wall contribute to distinguish them from other bacteria. Mycoplasma species are found both outside the cells as membrane surface parasites and inside the cells, where they become intracellular residents as "silent parasites". In humans, some Mycoplasma species are found as commensal inhabitants, while others have a significant impact on the cellular metabolism and physiology. Mollicutes lack typical bacterial PAMPs (e.g., lipoteichoic acid, flagellin, and some lipopolysaccharides) and consequently the exact molecular mechanisms of Mycoplasmas' recognition by the cells of the immune system is the subjects of several researches for its pathogenic implications. It is well known that several strains of Mycoplasma suppress the transcriptional activity of p53, resulting in reduced apoptosis of damaged cells. In addition, some Mycoplasmas were reported to have oncogenic potential since they demonstrated not just accumulation of abnormalities but also phenotypic changes of the cells. Aim of this review is to provide an update of the current literature that implicates Mycoplasmas in triggering inflammation and altering critical cellular pathways, thus providing a better insight into potential mechanisms of cellular transformation.

IMPLICACIONES DEL DOLOR CRÓNICO EN LA CALIDAD DE VIDA DE MUJERES CON FIBROMIALGIA

El objetivo de esta investigación fue comprender las implicaciones del dolor crónico en la calidad de vida de un grupo de mujeres diagnosticadas con fibromialgia. Para ello, se realizó un estudio cualitativo de diseño fenomenológico interpretativo en el que participaron 15 mujeres, con edades comprendidas entre los 23 y los 60 años. El análisis de los datos se realizó con el apoyo del programa Atlas.Ti. Los resultados indican que la intensidad de los síntomas, la interferencia del dolor crónico en actividades cotidianas, las alteraciones emocionales y las cogniciones negativas influyeron en su vida personal, familiar, social y laboral. Las estrategias de afrontamiento que asumieron las participantes facilitaron u obstaculizaron la aceptación de la enfermedad. Se concluye que el impacto de la fibromialgia en la calidad de vida depende más de las estrategias de afrontamiento que de los síntomas de la enfermedad. Las redes de apoyo facilitan el desarrollo de estrategias activas para afrontar la enfermedad.

Unique immunologic patterns in fibromyalgia

BACKGROUND

Fibromyalgia (FM) is a clinical syndrome characterized by chronic pain and allodynia. The diagnosis of FM has been one of exclusion as a test to confirm the diagnosis is lacking. Recent data highlight the role of the immune system in FM. Aberrant expressions of immune mediators, such as cytokines, have been linked to the pathogenesis and traits of FM. We therefore determined whether cytokine production by immune cells is altered in FM patients by comparing the cellular responses to mitogenic activators of stimulated blood mononuclear cells of a large number of patients with FM to those of healthy matched individuals.

METHODS

Plasma and peripheral blood mononuclear cells (PBMC) were collected from 110 patients with the clinical diagnosis of FM and 91 healthy donors. Parallel samples of PBMC were cultured overnight in medium alone or in the presence of mitogenic activators; PHA or PMA in combination with ionomycin. The cytokine concentrations of IFN-γ, IL-5, IL-6, IL-8, IL-10, MIP-1β , MCP-1, and MIP1-α in plasma as well as in cultured supernatants were determined using a multiplex immunoassay using bead array technology.

RESULTS

Cytokine levels of stimulated PBMC cultures of healthy control subjects were significantly increased as compared to matched non-stimulated PBMC cultures. In contrast, the concentrations of most cytokines were lower in stimulated samples from patients with FM compared to controls. The decreases of cytokine concentrations in patients samples ranged from 1.5-fold for MIP-1β to 10.2-fold for IL-6 in PHA challenges. In PMA challenges, we observed 1.8 to 4-fold decreases in the concentrations of cytokines in patient samples.

CONCLUSION

The cytokine responses to mitogenic activators of PBMC isolated from patients with FM were significantly lower than those of healthy individuals, implying that cell-mediated immunity is impaired in FM patients. This novel cytokine assay reveals unique and valuable immunologic traits, which, when combined with clinical patterns, can offer a diagnostic methodology in FM.

Comparison of the cortisol awakening response in women with shoulder and neck pain and women with fibromyalgia

Shoulder and neck pain (SNP) and fibromyalgia syndrome (FMS), two musculoskeletal conditions of unknown pathogenesis, share some common features in terms of altered neuroendocrine responses, pain and stress perception. However, the pain distribution in SNP is localized, whereas in FMS is more widespread. Because regional musculoskeletal pain may represent an intermediate stage along a continuum towards widespread musculoskeletal pain we compared the cortisol awakening response (CAR) in women with SNP with the CAR in FMS patients and healthy controls (HC) in a controlled hospital-hotel setting. The aim of the study was to investigate whether SNP is related to a deviant regulation of the hypothalamic-pituitary-adrenal (HPA) axis. Eighteen women with SNP, 29 female FMS patients, and 27 female HC participated in the study. Cortisol samples were collected upon awakening, 30 and 60 min later. Questionnaires measuring pain levels, sleeping problems, perceived stress, and psychological characteristics were administered to the participants. Compared with HC, women with SNP had a tendency towards higher cortisol levels, whereas FMS had lower cortisol levels. Adjustment for potential confounders did not influence the results. Women with SNP and FMS patients reported more health complaints, pain, and perceived stress than the HC, but women with SNP were less affected than the FMS patients. Women with SNP showed a tendency towards an elevated HPA axis activity compared with HC. The current findings may indicate that the hypercortisolism in regional musculoskeletal pain represent an intermediate stage towards the development of a hypocortisolism in widespread musculoskeletal pain.

Attitudes towards massage modify effects of manual therapy in breast cancer survivors: a randomised clinical trial with crossover design

Our aims were to investigate the immediate effect of myofascial release on heart rate variability and mood state, and the influence of attitude towards massage in breast cancer survivors with cancer-related fatigue. Twenty breast cancer survivors reporting moderate to high cancer-related fatigue participated in this crossover study. All patients presented to the laboratory at the same time of the day on two occasions separated by a 2-week interval. At each session, they received either a massage intervention or control intervention. Holter electrocardiogram recordings and Profile of Mood States questionnaire (six domains: tension-anxiety, depression-dejection, anger-hostility, vigour, fatigue, confusion) were obtained before and immediately after each intervention. The attitude towards massage scale was collected before the first session in all breast cancer survivors. The results showed a significant session × time interaction for standard deviation of the normal-to-normal interval (SDNN) (F= 5.063, P= 0.039), square root of mean squared differences of successive normal-to-normal intervals (RMSSD) (F= 8.273, P= 0.010), high-frequency component (HF) (F= 7.571, P= 0.013), but not for index heart rate variability (F= 3.451, P= 0.080), low-frequency component (LF) (F= 0.014, P= 0.997) and ratio LF/HF (F= 3.680, P= 0.072): significant increases in SDNN, RMSSD and HF domain (P < 0.05) were observed after the manual therapy intervention, with no changes after placebo (P > 0.6). No influence of the attitude scale on heart rate variability results was found. A significant session × time interaction was also found for fatigue (F= 5.101, P= 0.036) and disturbance of mood (F= 6.690, P= 0.018) scales of the Profile of Mood States: patients showed a significant decrease in fatigue and disturbance of mood (P < 0.001) after manual therapy, with no changes after placebo (P > 0.50). A significant influence of the attitude scale was observed in tension-anxiety, depression-dejection and anger-hostility scales. This controlled trial suggests that massage leads to an immediate increase of heart rate variability and an improvement in mood in breast cancer survivors with cancer-related fatigue. Further, the positive impact of massage on cancer-related fatigue is modulated by the attitude of the patient towards massage.

The functional status and well being of people with myalgic encephalomyelitis/chronic fatigue syndrome and their carers

BACKGROUND

Diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome or ME/CFS is largely based on clinical history, and exclusion of identifiable causes of chronic fatigue. Characterization of cases and the impact of interventions have been limited due to clinical heterogeneity and a lack of reliable biomarkers for diagnosis and outcome measures. People with ME/CFS (PWME) often report high levels of disability, which are difficult to measure objectively. The well being of family members and those who care for PWME are also likely to be affected. This study aimed to investigate the functional status and well being of PWME and their lay carers, and to compare them with people with other chronic conditions.

METHODS

We used a cross sectional design to study 170 people aged between 18 and 64 years with well characterized ME/CFS, and 44 carers, using SF-36 v2™. Mean physical and mental domains scores (scales and component summaries) were calculated and compared internally and externally with reference standards for the general population and for population groups with 10 chronic diseases.

RESULTS

SF-36 scores in PWME were significantly reduced, especially within the physical domain (mean norm-based Physical Component Summary (PCS) score = 26.8), but also within the mental domain (mean norm-based score for Mental Component Summary (MCS) = 34.1). The lowest and highest scale scores were for "Role-Physical" (mean = 25.4) and "Mental Health" (mean = 36.7) respectively. All scores were in general lower than those for the general population and diseased-specific norms for other diseases. Carers of those with ME/CFS tended to have low scores in relation to population norms, particularly within the mental domain (mean = 45.4).

CONCLUSIONS

ME/CFS is disabling and has a greater impact on functional status and well being than other chronic diseases such as cancer. The emotional burden of ME/CFS is felt by lay carers as well as by people with ME/CFS. We suggest the use of generic instruments such as SF-36, in combination of other objective outcome measurements, to describe patients and assess treatments.

Does Exercise Benefit Fibromyalgia?

This review discusses evidence-based perspectives on the potential benefits of exercise for fibromyalgia. Future directions for inquiry and clinical management also are addressed.

The effect of fibromyalgia and widespread pain on the clinically significant temporomandibular muscle and joint pain disorders--a prospective 18-month cohort study

Although most cases of temporomandibular muscle and joint disorders (TMJD) are mild and self-limiting, about 10% of TMJD patients develop severe disorders associated with chronic pain and disability. It has been suggested that fibromyalgia and widespread pain play a significant role in TMJD chronicity. This paper assessed the effects of fibromyalgia and widespread pain on clinically significant TMJD pain (GCPS II-IV). Four hundred eighty-five participants recruited from the Minneapolis/St. Paul area through media advertisements and local dentists received examinations and completed the Graded Chronic Pain Scale (GCPS) at baseline and at 18 months. Baseline widespread pain (OR: 2.53, P = .04) and depression (OR: 5.30, P = .005) were associated with onset of clinically significant pain (GCPS II-IV) within 18 months after baseline. The risk associated with baseline fibromyalgia was moderate, but not significant (OR: 2.74, P = .09). Persistence of clinically significant pain was related to fibromyalgia (OR: 2.48, P = .02) and depression (OR: 2.48, P = .02). These results indicate that these centrally generated pain conditions play a role in the onset and persistence of clinically significant TMJD.

PERSPECTIVE

Fibromyalgia and widespread pain should receive important consideration when evaluating and developing a treatment plan for patients with TMJD.

The effects of acute restraint stress on nociceptive responses evoked by the injection of formalin into the temporomandibular joint of female rats

The temporomandibular joint (TMJ) formalin test was used to evaluate the effects of acute restraint stress on the nociceptive behavioral responses of female rats during proestrus and estrus phases of the estrous cycle. Rats were subjected to one session of restraint stress (15, 30 min or 1 h). They were then either immediately killed to allow the collection of blood for hormonal radioimmunoassay determinations or subjected to TMJ formalin test to evaluate nociception. All stress protocols significantly raised the plasma concentrations of corticosterone. The performance of rats subjected to 15 and 30 min of restraint stress was similar to that of control rats, whereas rats that were stressed for 1 h showed a decrease in nociceptive responses, during both proestrus and estrus phases. The stress-induced analgesia (SIA) was greater in the proestrus phase. To evaluate the role of kappa-opioid receptors, the selective receptor kappa-opioid antagonist nor-binaltorphimine (nor-BNI; 200 microg or saline) was injected into the TMJ 24 h prior to the 1 h stress period and the TMJ formalin test. The local administration of nor-BNI partially reversed the SIA during the proestrus phase. These findings suggest that (1) acute stress for 1 h can produce analgesia both during proestrus and estrus phases; this effect is greater during the proestrus phase and (2) kappa-opioid receptor activation is involved in the SIA observed in the proestrus phase.

Cost effectiveness of pregabalin in the treatment of fibromyalgia from a UK perspective

BACKGROUND

Fibromyalgia is a chronic condition associated with widespread pain, sleep disturbance and disability. Disease related costs are high and effective treatment options few.

OBJECTIVES

To evaluate the cost effectiveness of pregabalin in the treatment of fibromyalgia.

METHODS

A decision-analytic model was developed comparing pregabalin 300 mg or 450 mg against placebo, duloxetine 60 mg or 120 mg, gabapentin, tramadol and amitriptyline. After a 12 week treatment phase patients who responded to treatment entered an ongoing treatment phase using a Markov model in which patients maintained response, lost response or dropped out. The base case considered patients with severe fibromyalgia defined as a Fibromyalgia Impact Questionnaire score of >or=59 and a pain score of >or=6.5 at baseline. Response rates for pregabalin and placebo were taken from three randomised trials, and a 1 year open-label extension study was used for long-term parameters. Response was defined as a >or=30% improvement over baseline in pain score and a patient global impression of change rating of much improved or very much improved. Relative rates of response for other comparators over placebo were extracted from a systematic review of published randomised controlled studies. The primary effectiveness endpoint was Quality Adjusted Life Years (QALYs). Utilities gained over baseline were estimated by applying the SF-6D utility algorithm to SF-36 data collected in the pregabalin trials. Resource use associated with fibromyalgia management was estimated from published studies and costs were estimated from the UK NHS perspective at 2008 prices. Costs and QALYs were discounted at 3.5%. Non-parametric bootstrapping analysis was used to generate confidence intervals.

RESULTS

In the base case, pregabalin 300 mg and 450 mg increased cost per patient by pound601 (95% CI: 532, 669) and pound653 (587, 727) and improved QALYs per patient by 0.03 (-0.03, 0.06) and 0.03 (-0.04, 0.08) respectively compared to placebo. The cost per QALY gained (CQG) was pound23,166 and pound22,533. In the base case population CQG for pregabalin 450 mg against duloxetine 60 mg and 120 mg was pound19,224 and pound14,096, against gabapentin pound35,737, against tramadol pound98,072, and was dominated by amitriptyline. Sensitivity analysis found the cost effectiveness of pregabalin to be most sensitive to drug price and response rates. Limitations of the analysis include different definitions of response used and lack of subgroup data reported in the published studies synthesised, and limited data on long-term effect of therapies in fibromyalgia. Although the analysis was based on the best available evidence, the comparisons against amitriptyline and tramadol rely on old studies that were not designed to meet current quality criteria.

CONCLUSION

This model found pregabalin 300 mg and 450 mg to be cost effective compared with placebo and, within the limits of available evidence, against duloxetine using standard UK criteria in patients with fibromyalgia experiencing severe pain.

Key symptom domains to be assessed in fibromyalgia (outcome measures in rheumatoid arthritis clinical trials)

This article discusses the key symptom domains to be assessed in fibromyalgia. Development of a consensus on a core set of outcome measures that should be assessed and reported in all clinical trials is needed to facilitate interpretation, pooling, and comparison of results. This aligns with the key objective of the Outcome Measures in Rheumatoid Arthritis Clinical Trials initiative to improve outcome measurement in rheumatic diseases through a data-driven interactive consensus process.

The assessment of vegetative and functional symptoms in fibromyalgia patients: the tropisetron experience

Vegetative and functional symptoms are, besides pain and tenderness of tender points, considered as additional information for the diagnosis of fibromyalgia (FM). In clinical trials, vegetative and functional symptoms have been included for selection of patients (e.g. sleep disturbances) and as secondary outcome parameters. Despite the relevance of these symptoms, no validated method is currently available but symptom lists are ad hoc developed by investigators. In this manuscript, data from a published double blind, randomised study are reanalysed which compared oral therapy over 10 days with 5 mg, 10 mg, and 15 mg to placebo in FM patients. This study applied a list of 17 vegetative and functional symptoms, which had to be scored by the patients by use of a 4-point severity scale (0 = none to 3 = severe). Factor analysis of the baseline data from 195 patients suggested to separate 6 sub-scales: Cardiovascular, gastrointestinal, psychiatric (sleep disturbance), nervous, autonomic system, and general disorders. Sleep disturbances, general symptoms (morning stiffness, fatigue) and autonomic symptoms (cold extremities, hyperhidrosis) were most severe in intensity. Analysis of sensitivity for treatment effects made use of differences between placebo and 5 mg tropisetron in changes between baseline and final assessment of the tropisetron trial. While, on the item level, differences in favour of tropisetron could only be demonstrated for sleep disorders, on the sub-scale level, also favourable effects of tropisetron could be shown for cardiovascular and nervous system complaints and, as a tendency, for general symptoms. On the other side, the sub-scale score of gastrointestinal symptoms worsened under tropisetron whilst it improved under placebo which effect was due to side effects of the active treatment. It is concluded that symptom clusters like sub-scales of a list of vegetative and functional symptoms will be more suitable for diagnostic purposes and evaluation of treatment outcome of clinical trials. Further research is urgently required which addresses the development of a FM-specific scale to assess vegetative and functional symptoms.

Adrenergic dysregulation and pain with and without acute beta-blockade in women with fibromyalgia and temporomandibular disorder

In patients with fibromyalgia syndrome (FMS) and temporomandibular disorder (TMD), stress and pain may chronically enhance sympathetic activity, altering cardiovascular responses and worsening pain. This study examined cardiovascular, epinephrine (EPI), norepinephrine (NE), cortisol and clinical pain responses in 54 female patients with these disorders and 34 controls. In a subsample of 10 FMS, 10 TMD patients and 16 controls, using a counterbalanced, double-blind, crossover design, the same responses were assessed after intravenous administration of low dose propranolol vs placebo. Testing included baseline, postural, speech and ischemic pain stressors. FMS patients showed lesser heart rate (HR) increases to posture challenge but greater blood pressure (BP) increases to postural and speech tasks than controls, as well as higher overall BP and greater total vascular resistance (TVR) than TMDs or controls. TMDs showed higher overall cardiac output and lower TVR than controls. Both FMS and TMD groups showed lower baseline NE than controls, and TMDs showed lower overall EPI and NE levels. Group differences in HR, EPI and NE were abolished after propranolol although BP, CO and TVR differences persisted. In both FMS and TMD, the number of painful body sites and ratings of total clinical pain obtained 4 times during each session were significantly lower after beta-blockade vs placebo.

PERSPECTIVE

These findings support the hypothesis that both FMS and TMD may frequently involve dysregulation of beta-adrenergic activity that contributes to altered cardiovascular and catecholamine responses and to severity of clinical pain. Acute treatment with low-dose propranolol led to short-term improvement in all these domains.

Compression on trigger points in the leg muscle increases parasympathetic nervous activity based on heart rate variability

Massotherapy, the therapeutic use of massage, is used to treat various chronic pain syndromes. One type of massotherapy, pressure stimulus applied over trigger points (TPs), is reported to have excellent therapeutic effects. Its effect is possibly mediated through changes in the autonomic nervous system although little research has been conducted to assess autonomic activity during TP compression. We have investigated how compression applied over TPs affects the autonomic nervous system. Six healthy young adult females whose daily working routine was carried out predominantly in a standing position were enrolled in the study cohort. After a day's work, the subjects were asked to rest supine, and electrocardiograms (ECGs), instantaneous lung volume (ILV) and systolic and diastolic blood pressures (SBP, DBP) were measured before and after pressure application over the TPs in those lower limb muscles where the subjects felt muscle fatigue or discomfort. The subjects were also asked to coordinate breathing with the beeping sounds. The therapeutic effects of TP compression were assessed by a subjective fatigue scale. Parasympathetic nervous activity was also assessed by spectral analysis of heart rate (HR) variability. The transfer function from ILV to HR was evaluated using linear analysis. The results indicated that TP compression (1) decreased HR, SBP and DBP, (2) increased parasympathetic activity, (3) increased the gain from ILV to HR, and (4) improved the fatigue scores. These findings suggest that an increase in parasympathetic nervous activity after the TP compression induced a reduction of fatigue. The therapeutic mechanisms of TP compression to enhance parasympathetic nervous system are discussed.

Fibromyalgia: nosography and therapeutic perspectives

Fibromyalgia (FM) is an important cause of morbidity and health expenditure. Severe widespread extra-articular chronic pain, along with nonrestorative sleep, dominates the clinical syndrome. The pathogenesis of FM remains unclear. While dysfunction in serotoninergic neurotransmission is believed to play an important role, several neurologic and immuno-endocrine mechanisms may also be relevant. A theory is advanced based on an inherited imbalance in neuro-vegetative systems resulting from increased sympathetic tone because of a metabolic deficiency in the serotoninergic system that, when exposed to a precipitating event, leads to the development of the clinical manifestations of FM. The importance of both nonpharmacological treatments and multimodal medication management is stressed.

Benefits of physical training in fibromyalgia and related syndromes

OBJECTIVE

To review the published information on physical training for fibromyalgia (FM) and related syndromes.

METHODS

A search of Medline literature (via Ovid and PubMed) with the following keywords: FM, chronic fatigue syndrome, therapy, rehabilitation, aerobic, exercise, and cognitive behavioral therapy. The reference lists of articles were examined for additional related articles.

RESULTS

Several studies investigated the benefits of graded exercise therapy for patients with FM or related syndromes. Although some systematic reviews have not established an unequivocal benefit of physical training, most authors report a benefit for patients with chronic pain or fatigue. Ideally, such a therapy should be a part of multidisciplinary program. Muscular rehabilitation is reserved for preventing the deconditioning syndrome often reported in patients and the vicious cycle of pain, avoidance and inactivity behaviors, or even kinesiophobia, deconditioning, incapacity and psychological distress.

CONCLUSION

This review emphasizes the relevance of graded physical training for treating FM and related syndromes. The development of rehabilitation centers, with experts able to propose a relevant therapy to patients with chronic pain or fatigue, should help alleviate this public health problem.

Posttraumatic stress disorder, tenderness, and fibromyalgia syndrome: are they different entities?

OBJECTIVES

Many features of fibromyalgia syndrome (FMS) resemble those of posttraumatic stress disorder (PTSD). The goal of this study was to investigate the comorbidity of FMS and PTSD in a cohort of men following an intensive, initial, defined traumatic event.

METHODS

One hundred twenty-four males (55 patients with PTSD, 20 patients with major depression, and 49 controls) were evaluated for the presence of FMS. The major traumatic events in all PTSD patients were combat-related. Each individual completed questionnaires characterizing his disease, disabilities, and quality of life.

RESULTS

Forty-nine percent of PTSD patients, compared to 5% of major depression patients and none of normal controls, fulfilled the American College of Rheumatology criteria for FMS (P<.0001). Significant correlations were detected between tender points and measured parameters in the PTSD group.

CONCLUSIONS

In male patients, PTSD is highly associated with FMS. The degree and impact of these disorders are also highly related.

Improvement in fibromyalgia symptoms with acupuncture: results of a randomized controlled trial

OBJECTIVE

To test the hypothesis that acupuncture improves symptoms of fibromyalgia.

PATIENTS AND METHODS

We conducted a prospective, partially blinded, controlled, randomized clinical trial of patients receiving true acupuncture compared with a control group of patients who received simulated acupuncture. All patients met American College of Rheumatology criteria for fibromyalgia and had tried conservative symptomatic treatments other than acupuncture. We measured symptoms with the Fibromyalgia Impact Questionnaire (FIQ) and the Multidimensional Pain Inventory at baseline, immediately after treatment, and at 1 month and 7 months after treatment. The trial was conducted from May 28, 2002, to August 18, 2003.

RESULTS

Fifty patients participated in the study: 25 in the acupuncture group and 25 in the control group. Total fibromyalgia symptoms, as measured by the FIQ, were significantly improved in the acupuncture group compared with the control group during the study period (P = .01). The largest difference in mean FIQ total scores was observed at 1 month (42.2 vs 34.8 in the control and acupuncture groups, respectively; P = .007). Fatigue and anxiety were the most significantly improved symptoms during the follow-up period. However, activity and physical function levels did not change. Acupuncture was well tolerated, with minimal adverse effects.

CONCLUSION

This study paradigm allows for controlled and blinded clinical trials of acupuncture. We found that acupuncture significantly improved symptoms of fibromyalgia. Symptomatic improvement was not restricted to pain relief and was most significant for fatigue and anxiety.

The epidemiology of chronic syndromes that are frequently unexplained: do they have common associated factors?

BACKGROUND

Syndromes for which no physical or pathological changes can be found tend to be researched and managed in isolation although hypotheses suggest that they may be one entity. The objectives of our study were to investigate the co-occurrence, in the general population, of syndromes that are frequently unexplained and to evaluate whether they have common associated factors.

METHODS

We conducted a population-based cross-sectional survey that included 2,299 subjects who were registered with a General Medical Practice in North-west England and who completed full postal questionnaires (response rate 72%). The study investigated four chronic syndromes that are frequently unexplained: chronic widespread pain, chronic oro-facial pain, irritable bowel syndrome, and chronic fatigue. Validated instruments were used to measure the occurrence of syndromes and to collect information on a variety of associated factors: demographic (age, gender), psychosocial (anxiety, depression, illness behaviour), life stressors, and reporting of somatic symptoms.

RESULTS

We found that 587 subjects (27%) reported one or more syndromes: 404 (18%) reported one, 134 (6%) reported two, 34 (2%) reported three, and 15 (1%) reported all four syndromes. The occurrence of multiple syndromes was greater than would be expected by chance (P < 0.001). There were factors that were common across syndromes: female gender [odds ratio (OR) = 1.8; 95% confidence interval (95% CI) 1.5-2.2], high levels of aspects of health anxiety like health worry preoccupation (OR = 3.5; 95% CI 2.8-4.4) and reassurance seeking behaviour (OR = 1.4; 95% CI 1.1-1.7), reporting of other somatic symptoms (OR = 3.6; 95% CI 2.9-4.4), and reporting of recent adverse life events (OR = 2.3; 95% CI 1.9-2.8).

CONCLUSION

This study has shown that chronic syndromes that are frequently unexplained co-occur in the general population and share common associated factors. Primary care practitioners need to be aware of these characteristics so that management is appropriate at the outset.

Estrogen regulates adrenal medullary function producing sexual dimorphism in nociceptive threshold and beta-adrenergic receptor-mediated hyperalgesia in the rat

Epinephrine produces sexually dimorphic beta(2)-adrenergic receptor-mediated mechanical hyperalgesia, with male rats exhibiting greater hyperalgesia. Because female rats have higher plasma epinephrine levels, and beta-adrenergic receptor sensitivity is affected by chronic exposure to agonists, we tested the hypothesis that this sexual dimorphism is due to epinephrine-induced desensitization of beta(2)-adrenergic receptors. Following gonadectomy, epinephrine hyperalgesia, as measured by the Randall-Selitto paw-withdrawal test, was unchanged in male rats while in females it was increased. Prepubertal male and female rats do not demonstrate sexual dimorphism in either plasma epinephrine level or epinephrine-induced hyperalgesia. Adrenal medullectomy and adrenal denervation both significantly enhanced epinephrine hyperalgesia, but only in females. In contrast, the sexually dimorphic hyperalgesia induced by prostaglandin E(2), another agent that acts directly to sensitize primary afferent nociceptors, was not enhanced by adrenal medullectomy or denervation. Chronic administration of epinephrine in male rats, to produce plasma levels similar to those of gonad-intact females, significantly attenuated epinephrine-induced hyperalgesia, making it similar to that in females. These results strongly support the suggestion that estrogen regulates plasma epinephrine in female rats and differential sensitivity to beta(2)-adrenergic agonists accounts for the sexual dimorphism in epinephrine-induced hyperalgesia. Unexpectedly, regulation of adrenal medullary function by estrogen was also found to modulate baseline nociceptive threshold such that females had a lower nociceptive threshold.

Repeated sound stress enhances inflammatory pain in the rat

While it is well established that acute stress can produce antinociception, a phenomenon referred to as stress-induced analgesia, repeated exposure to stress can have the opposite effect. Since, chronic pain syndromes, such as fibromyalgia and rheumatoid arthritis, may be triggered and/or exacerbated by chronic stress, we have evaluated the effect of repeated stress on mechanical nociceptive threshold and inflammatory hyperalgesia. Using the Randall-Selitto paw pressure test to quantify nociceptive threshold in the rat, we found that repeated non-habituating sound stress enhanced the mechanical hyperalgesia induced by the potent inflammatory mediator, bradykinin, which, in normal rats, produces hyperalgesia indirectly by stimulating the release of prostaglandin E2 from sympathetic nerve terminals. Hyperalgesia induced by the direct-acting inflammatory mediator, prostaglandin E2 as well as the baseline nociceptive threshold, were not affected. Adrenal medullectomy or denervation, reversed the effect of sound stress. In sound stressed animals, bradykinin-hyperalgesia had a more rapid latency to onset and was no longer inhibited by sympathectomy, compatible with a direct effect of bradykinin on primary afferent nociceptors. In addition, implants of epinephrine restored bradykinin-hyperalgesia in sympathectomized non-stressed rats, lending further support to the suggestion that increased plasma levels of epinephrine can sensitize primary afferents to bradykinin. These results suggest that stress-induced enhancement of inflammatory hyperalgesia is associated with a change in mechanism by which bradykinin induces hyperalgesia, from being sympathetically mediated to being sympathetically independent. This sympathetic-independent enhancement of mechanical hyperalgesia is mediated by the stress-induced release of epinephrine from the adrenal medulla.

Myofascial pain: Diagnosis and management

Clinical understanding and management of myofascial pain is overlooked frequently when dealing with pain. Myofascial pain is defined as pain or autonomic phenomena referred from active trigger points, with associated dysfunction. The trigger point is a focus of hyperirritability in the muscle that, when compressed, is locally tender and, if sensitized, gives rise to referred pain and tenderness. The pain quality is dull or achy and associated with autonomic changes. Myofascial pain is poorly understood, which results too often in underdiagnosis and poor management. The pathogenesis likely has a central mechanism with peripheral clinical manifestations. The therapy for myofascial pain requires enhancing central inhibition through pharmacology or behavioral techniques and simultaneously reducing peripheral inputs through physical therapies including exercises and trigger point-specific therapy.

Electrodermal dissociation of chronic fatigue and depression: evidence for distinct physiological mechanisms

Chronic fatigue syndrome (CFS) has an estimated prevalence between 0.5% and 3%, yet its diagnosis remains contentious. CFS is characterized by subjective symptoms that can be difficult to verify; moreover, depression is a commonly reported CFS complaint, whereas fatigue is a common symptom of depression. Our primary goal was dissociation of these disorders using psychophysiological methods. As previous research has implicated the autonomic nervous system in CFS, we conducted what we believe to be the first analysis of bilateral electrodermal and skin temperature responses of dextral females in a cross-modal orienting task, to investigate differences between these two patient groups and controls. A multivariate analysis of variance (MANOVA) examining three measures of electrodermal activity revealed prestimulus tonic skin conductance levels (SCLs) were markedly lower for the CFS group, with no difference between controls and depressives. Concurrent skin temperature levels were higher for the CFS group than the other two groups. These findings indicate that, despite overtly similar cognitive and symptom profiles, depression and CFS patients can be differentiated with psychophysiological measures. This study adds to the growing body of evidence demonstrating that CFS and depression have distinct neurobiological profiles, consistent with unique aetiologies.

[Diagnosis and clinical signs of fibromyalgia]

According to the criteria of the American College of Rheumatology (ACR 1990) fibromyalgia can be classified as a complex of clinical symptoms. It is characterised by widespread muscle pain, and pain in at least 11 out of 18 defined so-called tender points. The widespread muscle pain must be present for at least 3 months. For the diagnosis of fibromyalgia many other rheumatological, neurological and psychiatric diseases have to be excluded; additional autonomic or functional symptoms are usual. Routine laboratory or radiological examinations yield normal results. From a pathogenetic point of view endocrine disturbances and psychosocial stress factors are found. In most cases the clinical course shows a slow development of generalised pain.

Normal production of inflammatory cytokines in chronic fatigue and fibromyalgia syndromes determined by intracellular cytokine staining in short-term cultured blood mononuclear cells

It has been proposed that cytokines play a role in the pathogenesis of chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FMS). However, different studies have reported conflicting results using enzyme-linked immunosorbent assay or polymerase chain reaction to detect cytokines in these conditions. In the present study, for the first time, the production of inflammatory [interleukin (IL)-1alpha, IL-6, and TNF-alpha] and anti-inflammatory (IL-10) cytokines by CD14+ and CD14- peripheral blood mononuclear cells (PBMC) from chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FMS) patients and sex- and age-matched normal subjects was investigated at the level of individual cells using the technique of intracellular cytokine staining and flow cytometry. Cultures were carried out in the presence of polymyxin B to inhibit the effect of endotoxins on cytokine production by monocytes. The mean intensity of fluorescence (MIF) and percentage of CD14+ (monocytes) and CD14- (lymphocytes) cytokine-producing mononuclear cells were comparable in patients and controls in either unstimulated or IFN-gamma-stimulated conditions. Our study indicates that dysregulation of cytokine production by circulating monocytes or non-monocytic cells (lymphocytes) is not a dominant factor in the pathogenesis of CFS/FMS.

Chiari type I malformation revisited: diagnosis and treatment

BACKGROUND

Chiari type I malformations (Chiari I) are congenital deformities where caudal migration of the cerebellar tonsils through the foramen magnum compresses the cerebellum and cervicomedullary junction (lower brainstem and upper cervical spinal cord). Associations with chronic fatigue syndrome, fibromyalgia, orthostatic intolerance, and other neurologic syndromes have been proposed along with the current plethora of known symptoms of this disease process. In advanced cases, Chiari I malformations can lead to significant neurologic deficit and be the cause of permanent nervous system damage.

REVIEW SUMMARY

This article focuses on the clinical diagnosis and treatment of patients with Chiari I, including a discussion on the possible mechanisms of Chiari I with a review of present diagnostic tests, indications for treatment, and appraisal of surgical outcome.

CONCLUSIONS

Future radiological advances and research will undoubtedly be directed to better understanding of the pathology of the Chiari malformation and more effective medical and surgical treatment.