Fibromyalgia: generalized pain intolerance and manifold symptom reporting

We tested the current criteria for fibromyalgia. Pain tolerance was measured at tender point and control point sites using a pressure algometer, and responses to 6 standard psychological self-reports were obtained from 125 patients with generalized nonarticular rheumatism, rheumatoid arthritis, or osteoarthritis. Among patients with generalized nonarticular rheumatism, published symptom criteria for fibromyalgia did not correlate significantly with the number of tender points. Only lower generalized pressure point pain tolerance distinguished fibromyalgia from other generalized nonarticular rheumatism. Generalized nonarticular rheumatism mean scores were much higher than controls on tests measuring the tendency to report physical symptoms, including headaches and functional bowel syndrome. It is probable that patients with fibromyalgia do not differ in any important physical or psychological respect from other patients with generalized nonarticular rheumatism except for the presence of tender points. However, the presence of tender points is merely a reflection of the patient's general pressure pain sensitivity and is not indicative of any special localized pathological phenomenon. The concept of fibromyalgia as an entity separate from the rest of generalized nonarticular rheumatism may be an artifact of a physician's approach to the patient. Most patients with generalized nonarticular rheumatism demonstrate an abnormally high frequency of reporting manifold disagreeable symptoms and probably come to the attention of many medical disciplines.     

Evidence of qualitatively altered nociception in patients with fibromyalgia

Objective. To investigate the perception of pain in tender muscles of patients with fibromyalgia. Methods. Twenty-five women with fibromyalgia and 25 healthy women were examined. Seven different pressure intensities were used to palpate a highly tender muscle and a largely normal muscle. Subjects then recorded their response to induced pain on a visual analog scale. The examiner was blinded to each subject's response. Results. The stimulus-response function for pressure versus pain recorded for normal muscle was well described by a power function. For highly tender muscle, the stimulus-response function was displaced toward lower pressures and, more importantly, it was linear, i.e., qualitatively different from that of normal muscle. Conclusion. This study demonstrates that nociception is qualitatively altered in patients with fibromyalgia, which is consistent with recent findings in other patients with tender muscles. The data strongly indicate that fibromyalgic pain, at least in part, is due to aberrant central pain mechanisms.     

Decreased pain threshold in children with growing pains

OBJECTIVE: To investigate whether children with recurrent musculoskeletal pain termed growing pains (GP) have lower pain thresholds than children without GP. METHODS: We measured the pain threshold of 44 children with GP and 46 controls. Pain thresholds were measured by use of a Fisher type dolorimeter with pressure applied to areas associated with increased tenderness in fibromyalgia (FM), control points, and anterior tibia, the usual region of pain in children with GP. Unpaired Student's t test and chi-square tests were used to compare the pain threshold and number of tender points in patients and controls. RESULTS: The pain threshold in characteristic tender points of FM, control points, and anterior tibia in the children with GP was significantly lower in children with GP (3.5 +/- 0.6 kg/cm2 in GP versus 4.0 +/- 0.7 in controls, p < 0.001, 3.8 +/- 0.7 versus 4.4 +/- 0.8, p = 0.005; 5.1 +/- 1.1 versus 5.9 +/- 1.5, p = 0.004). Children with GP had a significantly greater number of tender points in response to an applied pressure of 4 kg/cm2. CONCLUSION: Children with GP have more tender points and lower pain thresholds than children without GP indicating that GP may represent a variant of a noninflammatory pain syndrome in younger children.     

A double‐blind,multicenter trial comparing duloxetine with placebo in the treatment of fibromyalgia patients with or without major depressive disorder

Objective

To assess the efficacy and safety of duloxetine, a serotonin and norepinephrine reuptake inhibitor, in subjects with primary fibromyalgia, with or without current major depressive disorder.

Methods

This study was a randomized, double‐blind, placebo‐controlled trial conducted in 18 outpatient research centers in the US. A total of 207 subjects meeting the American College of Rheumatology criteria for primary fibromyalgia were enrolled (89% female, 87% white, mean age 49 years, 38% with current major depressive disorder). After single‐blind placebo treatment for 1 week, subjects were randomly assigned to receive duloxetine 60 mg twice a day (n = 104) or placebo (n = 103) for 12 weeks. Co–primary outcome measures were the Fibromyalgia Impact Questionnaire (FIQ) total score (score range 0–80, with 0 indicating no impact) and FIQ pain score (score range 0–10). Secondary outcome measures included mean tender point pain threshold, number of tender points, FIQ fatigue, tiredness on awakening, and stiffness scores, Clinical Global Impression of Severity (CGI‐Severity) scale, Patient Global Impression of Improvement (PGI‐Improvement) scale, Brief Pain Inventory (short form), Medical Outcomes Study Short Form 36, Quality of Life in Depression Scale, and Sheehan Disability Scale.

Results

Compared with placebo‐treated subjects, duloxetine‐treated subjects improved significantly more (P = 0.027) on the FIQ total score, with a treatment difference of −5.53 (95% confidence interval −10.43, −0.63), but not significantly more on the FIQ pain score (P = 0.130). Compared with placebo‐treated subjects, duloxetine‐treated subjects had significantly greater reductions in Brief Pain Inventory average pain severity score (P = 0.008), Brief Pain Inventory average interference from pain score (P = 0.004), number of tender points (P = 0.002), and FIQ stiffness score (P = 0.048), and had significantly greater improvement in mean tender point pain threshold (P = 0.002), CGI‐Severity (P = 0.048), PGI‐Improvement (P = 0.033), and several quality‐of‐life measures. Duloxetine treatment improved fibromyalgia symptoms and pain severity regardless of baseline status of major depressive disorder. Compared with placebo‐treated female subjects (n = 92), duloxetine‐treated female subjects (n = 92) demonstrated significantly greater improvement on most efficacy measures, while duloxetine‐treated male subjects (n = 12) failed to improve significantly on any efficacy measure. The treatment effect on significant pain reduction in female subjects was independent of the effect on mood or anxiety. Duloxetine was safely administered and well tolerated.

Conclusion

In this randomized, controlled, 12‐week trial (with a 1‐week placebo lead‐in phase), duloxetine was an effective and safe treatment for many of the symptoms associated with fibromyalgia in subjects with or without major depressive disorder, particularly for women, who had significant improvement across most outcome measures.

     

Primary juvenile fibromyalgia. Psychological adjustment,family functioning,coping, and functional disability

Objectives. 1) To determine the importance of psychological adjustment and family functioning in primary juvenile fibromyalgia by assessing these factors in children with fibromyalgia and in their parents, compared with children with juvenile rheumatoid arthritis (JRA) and with pain-free control children and their parents. 2) To examine which of these factors predict functional disability. Methods. Fifteen children in each of the 3 study groups, and their parents, completed self-report questionnaires and pain diaries. A medical evaluation of each child was performed, including assessment of tender points by palpation and by dolorimetry. Results. All children in the fibromyalgia group met the Yunus and Masi criteria for fibromyalgia, and 11 met the American College of Rheumatology criteria. There were almost no significant group differences in the children's or parents' psychological adjustment, ratings of family functioning, or coping strategies. Significant group differences in functional disability, pain, fatigue, tender point threshold, and control point tolerance were found. A number of the psychological adjustment, pain, fatigue, and coping variables were significantly associated with functional disability. Conclusion. The notion that fibromyalgia is a psychogenic condition is not supported by these results. Fibromyalgia is associated with disability of a magnitude comparable to that of other chronic pain conditions. Disability among children with fibromyalgia or JRA is a function of the children's psychological adjustment and physical state, and of the parents' physical state and method of coping with pain.     

Oxidative stress in fibromyalgia and its relationship to symptoms

Oxidative stress is thought to play a role in the pathogenesis of fibromyalgia. We examined the hypothesis that oxidative stress was increased in patients with fibromyalgia and related to the severity of symptoms. Urinary F₂-isoprostane excretion was measured in 48 patients with fibromyalgia and compared to those of 96 control subjects. In patients, we examined the association between oxidative stress and symptoms. Patients with fibromyalgia were significantly more symptomatic than control subjects, but urinary F₂-isoprostane excretion did not differ significantly (2.3 ± 1.9 vs. 2.8 ± 2.2 ng/mg creatinine, p = 0.16). In patients with fibromyalgia, F₂-isoprostane excretion was associated with fatigue visual analog scale (rho = 0.30, p = 0.04) but not with pain, quality of life, functional capacity, depression, number of tender points, or overall impact of fibromyalgia. Oxidative stress is not increased in patients with fibromyalgia, but as was previously found in patients with systemic lupus erythematosus, oxidative stress was associated with fatigue. Jason D. Morrow: deceased     

Evidence of augmented central pain processing in idiopathic chronic low back pain

OBJECTIVE: For many individuals with chronic low back pain (CLBP), there is no identifiable cause. In other idiopathic chronic pain conditions, sensory testing and functional magnetic resonance imaging (fMRI) have identified the occurrence of generalized increased pain sensitivity, hyperalgesia, and altered brain processing, suggesting central augmentation of pain processing in such conditions. We compared the results of both of these methods as applied to patients with idiopathic CLBP (n = 11), patients with widespread pain (fibromyalgia; n = 16), and healthy control subjects (n = 11). METHODS: Patients with CLBP had low back pain persisting for at least 12 months that was unexplained by MRI/radiographic changes. Experimental pain testing was performed at a neutral site (thumbnail) to assess the pressure-pain threshold in all subjects. For fMRI studies, stimuli of equal pressure (2 kg) and of equal subjective pain intensity (slightly intense pain) were applied to this same site. RESULTS: Despite low numbers of tender points in the CLBP group, experimental pain testing revealed hyperalgesia in this group as well as in the fibromyalgia group; the pressure required to produce slightly intense pain was significantly higher in the controls (5.6 kg) than in the patients with CLBP (3.9 kg) (P = 0.03) or the patients with fibromyalgia (3.5 kg) (P = 0.006). When equal amounts of pressure were applied to the 3 groups, fMRI detected 5 common regions of neuronal activation in pain-related cortical areas in the CLBP and fibromyalgia groups (in the contralateral primary and secondary [S2] somatosensory cortices, inferior parietal lobule, cerebellum, and ipsilateral S2). This same stimulus resulted in only a single activation in controls (in the contralateral S2 somatosensory cortex). When subjects in the 3 groups received stimuli that evoked subjectively equal pain, fMRI revealed common neuronal activations in all 3 groups. CONCLUSION: At equal levels of pressure, patients with CLBP or fibromyalgia experienced significantly more pain and showed more extensive, common patterns of neuronal activation in pain-related cortical areas. When stimuli that elicited equally painful responses were applied (requiring significantly lower pressure in both patient groups as compared with the control group), neuronal activations were similar among the 3 groups. These findings are consistent with the occurrence of augmented central pain processing in patients with idiopathic CLBP.     

Effects of functional training on pain,leg strength,and balance in women with fibromyalgia

Aim: The aim of this study was to analyze the effect of 18-week functional training (FT) program consisting in two sessions a week of in-water exercise and one of on-land exercise on pain, strength, and balance in women with fibromyalgia.

Methods: A sample consisting of 36 fibromyalgia patients was included in the study. The patients were allocated randomly into the experimental group (EG, n = 20), and control group (CG, n = 16). Standardized field-based fitness tests were used to assess muscle strength (30-s chair stand and handgrip strength) and agility/dynamic balance and static balance. Fibromyalgia impact and pain were analyzed by Fibromyalgia Impact Questionnaire (FIQ), tender points (TPs), visual analog scale (VAS).

Results: We observed a significant reduction in the FIQ (p = 0.042), the algometer scale of TP (p = 0.008), TP (p < 0.001), and VAS (p < 0.001) in the EG. The EG shows better results in leg strength (p < 0.001), handgrip strength (p = 0.025), agility/dynamic balance (p = 0.032) and balance (p = 0.006).

Conclusions: An 18-week intervention consisting in two sessions of in-water exercise and one session of on-land exercise of FT reduces pain and improves functional capacity in FM patients. These results suggested that FT could play an important role in maintaining an independent lifestyle in patients with FM.     

Evoked pain measures in fibromyalgia

Fibromyalgia is defined by widespread pain and tenderness at a minimum of 11 of 18 defined tender points. Current evidence indicates that tender points are not unique to fibromyalgia and are simply regions in the body where all people are more tender. Tenderness (i.e. sensitivity to pressure) is widespread in fibromyalgia rather than being confined to tender points, and patients are also more sensitive to heat, cold and electrical stimulation. Using the number of painful tender points as a measure of tenderness is clinically expedient but is theoretically vulnerable to bias and is influenced by subjective distress. Other means of assessing tenderness (e.g. pressure dolorimeter devices, or more elaborate psychophysical methods) demonstrate the same increased pain sensitivity in fibromyalgia that is noted with tender point assessments, but these measures are relatively independent of biasing factors or distress. Fibromyalgia is one of only a few syndromes defined by the presence of both spontaneous (i.e. clinical) and evoked (i.e. experimental) pain. While the issues associated with the evaluation of spontaneous pain are shared with all chronic pain syndromes, the issues associated with the evaluation of evoked pain sensitivity are specific to fibromyalgia and related musculoskeletal disorders. This chapter focuses on the evaluation of altered pain sensitivity in fibromyalgia. It describes current measurement methodology, briefly reviews studies of sensitivity to experimentally evoked painful and non-painful sensations, analyses the factors assessed by different measurement methodologies, and concludes with recommendations for future diagnostic criteria and measurement methods.     

Influence of catechol-O-methyltransferase (COMT) gene polymorphisms in pain sensibility of Brazilian fibromialgia patients

Fibromyalgia syndrome (FS) is a rheumatic syndrome affecting to 2–3% of individuals of productive age, mainly women. Neuroendocrine and genetic factors may play a significant role in development of the disease which is characterized by diffuse chronic pain and presence of tender points. Several studies have suggested an association between FS, especially pain sensitivity, and polymorphism of the catechol-O-methyltransferase (COMT) gene. The aim of the present study was to characterize the SNPs rs4680 and rs4818 of the COMT gene and assess its influence in pain sensitivity of patients with fibromyalgia screened by the Fibromyalgia Impact Questionnaire (FIQ). DNA was extracted from peripheral blood of 112 patients with fibromyalgia and 110 healthy individuals and was used as template in PCR for amplification of a 185-bp fragment of the COMT gene. The amplified fragment was sequenced for analyses of the SNPs rs4680 and rs4818. The frequency of mutant genotype AA of SNP rs6860 was 77.67% in patients with FS and 28.18% for the control group. For the SNP rs4818, the frequency of mutant genotype CC was 73.21 and 39.09% for patients with FS and controls, respectively. Moreover, the FIQ score was higher in patients with the homozygous mutant genotype for SNPs rs4680 (87.92 points) and rs4818 (86.14 points). These results suggest that SNPs rs4680 and rs4818 of the COMT gene may be associated with fibromyalgia and pain sensitivity in FS Brazilian patients.     

High frequency of fibromyalgia in patients with chronic fatigue seen in a primary care practice

We administered a standardized history questionnaire and performed a tender point examination on 27 patients with debilitating fatigue of at least 6 months duration, seen in a primary care practice, as well as on 20 patients with fibromyalgia. Sixteen of the 27 patients with chronic fatigue met the full criteria for the working case definition of chronic fatigue syndrome (CFS). Eight patients with chronic fatigue denied having any current persistent, diffuse musculoskeletal pain, and their tender point scores were similar to those in 10 normal control subjects. In contrast, 19 patients with chronic fatigue (70%) had persistent, diffuse musculoskeletal pain. The results of their tender point examinations were similar to those of the patients with fibromyalgia. Thus, the majority of these patients with debilitating chronic fatigue, including those who met criteria for CFS, met the historical and tender point diagnostic criteria for fibromyalgia. The presence of current musculoskeletal pain will identify those CFS patients who have fibromyalgia.     

Low levels of somatomedin C in patients with the fibromyalgia syndrome. A possible link between sleep and muscle pain

Objective. Fibromyalgia is a common syndrome of musculoskeletal pain and fatigue. Lacking distinctive tissue or laboratory correlations, it has often been considered a form of “psychogenic rheumatism.” In the present study, the notion that the stage-4 sleep anomaly typically seen in the fibromyalgia syndrome may disrupt growth hormone secretion was tested. Because growth hormone has a very short half-life, serum levels of somatomedin C were measured; somatomedin C is the major mediator of growth hormone's anabolic actions and is a prerequisite for normal muscle homeostasis. Methods. Serum levels of somatomedin C were measured in 70 female fibromyalgia patients and 55 healthy controls, using a peptide-specific radioimmunoassay. Results. Significantly lower levels of somatomedin C were observed in the fibromyalgia patients compared with controls (mean ± SD 124.7 ± 47 ng/ml versus 175.2 ± 60 ng/ml; P = 0.000001). These results could not be explained by concomitant therapy or by weight, and in a subset of 21 patients in whom this was investigated, there was no correlation with various indices of disease activity. Conclusion. These findings indicate that there is a distinctive disruption of the growth hormone-somatomedin C neuroendocrine axis in a majority of fibromyalgia patients. It is hypothesized that this abnormality may explain the link between disturbed sleep and predisposition to muscle pain.     

Preliminary criteria for primary fibromyalgia syndrome (PFS): multivariate analysis of a consecutive series of PFS, other pain patients, and normal subjects

Primary fibromyalgia syndrome (PFS) is a common form of nonarticular rheumatism with chronic and generalized musculoskeletal aching and stiffness, accompanied by tender points at characteristic sites in the absence of an underlying condition. No satisfactory criteria for its diagnosis, based on appropriate controlled studies, have yet been proposed. We undertook such a study which included a consecutive series of clinically diagnosed PFS and compared them with 3 control groups--mild rheumatoid arthritis, localized fibromyalgia secondary to trauma and normal controls. Multivariate statistical analysis plus clinical judgement identified 6 historical features and 7 pairs of tender points that best discriminated PFS from the control groups. The criteria, derived from a combination of these historical features and tender points, provided greater than 90% sensitivity and specificity. In an independent and consecutive sample of 45 PFS patients, the criteria yielded a sensitivity of 89%. The present study indicates that a combination of historical features and TP's will likely provide effective PFS criteria.     

Measurement of pain threshold in patients with rheumatoid arthritis,osteoarthritis, ankylosing spondylitis,and healthy controls

Summary Pain threshold was measured using a pressure algometer in 126 subjects, of whom 54 were females and 72 males. These subjects included 18 males and 18 females with rheumatoid arthritis, 18 males and 18 females with osteoarthritis, 18 males with ankylosing spondylitis, and 18 male and 18 female healthy control volunteers. Six points were studied on each side of the body: 2 cm above the eyebrow on the forehead, lateral aspect of the arm at the insertion of the deltoid muscle, midpoint of the ulna, hypothenar eminence in the palm, midpoint of the quadriceps muscle, and midpoint of the anteromedial aspect of the tibia. None of these points corresponded to the trigger points in fibromyalgia. The pain threshold was statistically significantly higher in patients with ankylosing spondylitis than in patients with osteoarthritis, and these in turn were statistically higher than in the normal subjects. Patients with rheumatoid arthritis had significantly lower pain thresholds than the normal subjects. No laterality in pain threshold was identified, but females had in general a lower pain threshold.     

Quantifying pain threshold and quality of life of fibromyalgia patients

The most typical symptom of fibromyalgia (FM) is diffuse pain, and pain at specific points—tender points—is crucial for its diagnosis. By comparing healthy individuals and FM patients, this study was aimed at assessing pain and quality of life of Brazilian females with FM, while seeking for a correlation between pain threshold and quality of life. A total of 178 women were evaluated: 124 were FM patients and 54 were healthy women. Pain threshold at tender points was quantified by dolorimetry, and diffuse pain by means of the visual analogue scale (VAS); the Fibromyalgia Impact Questionnaire (FIQ) was used to evaluate quality of life. Statistical treatment of the data allowed for proposing two indexes: a pain threshold index (PT) and a quality of life one (QOL). PT is the lowest value among all pain thresholds measured at the 18 tender points; QOL is the mean of responses to the FIQ and VAS. Both indexes were tested and showed significant differences between the test and control groups. By pairing pain threshold values of each tender point in the test and control groups, it was found that the most sensitive points matched between the two groups, that is, the most sensitive anatomic spots in a healthy individual are also likely to be the most sensitive points in a person with FM. This suggests that a stimulus that provokes slight discomfort to a healthy person may produce more pain in FM patients—which may bear implications for FM clinical treatment. In this sample of Brazilian women, FM patients had both lower pain threshold and worse quality of life than healthy women.     

A randomized,sham‐controlled,proof of principle study of transcranial direct current stimulation for the treatment of pain in fibromyalgia

Objective

Recent evidence suggests that fibromyalgia is a disorder characterized by dysfunctional brain activity. Because transcranial direct current stimulation (tDCS) can modulate brain activity noninvasively and can decrease pain in patients with refractory central pain, we hypothesized that tDCS treatment would result in pain relief in patients with fibromyalgia.

Methods

Thirty‐two patients were randomized to receive sham stimulation or real tDCS with the anode centered over the primary motor cortex (M1) or the dorsolateral prefrontal cortex (DLPFC) (2 mA for 20 minutes on 5 consecutive days). A blinded evaluator rated the patient's pain, using the visual analog scale for pain, the clinician's global impression, the patient's global assessment, and the number of tender points. Other symptoms of fibromyalgia were evaluated using the Fibromyalgia Impact Questionnaire and the Short Form 36 Health Survey. Safety was assessed with a battery of neuropsychological tests. To assess potential confounders, we measured mood and anxiety changes throughout the trial.

Results

Anodal tDCS of the primary motor cortex induced significantly greater pain improvement compared with sham stimulation and stimulation of the DLPFC (P < 0.0001). Although this effect decreased after treatment ended, it was still significant after 3 weeks of followup (P = 0.004). A small positive impact on quality of life was observed among patients who received anodal M1 stimulation. This treatment was associated with a few mild adverse events, but the frequency of these events in the active‐treatment groups was similar to that in the sham group. Cognitive changes were similar in all 3 treatment groups.

Conclusion

Our findings provide initial evidence of a beneficial effect of tDCS in fibromyalgia, thus encouraging further trials.

     

Relationship between the body image and level of pain, functional status, severity of depression, and quality of life in patients with fibromyalgia syndrome

The aims were to investigate how the body image is affected in fibromyalgia syndrome (FMS) in comparison to healthy people, as well as to explore the relationship of the body image with the level of pain, functional status, severity of depression, and quality of life (QoL). Demographic variables, symptoms of fibromyalgia, and number of fibromyalgia tender points for 51 patients with FMS and 41 control subjects were recorded. All patients were asked to mark the level of pain on visual analogue scale (VAS). Six-minute walking test was recorded for functional assessment. The impact of the disease was evaluated by fibromyalgia impact questionnaire (FIQ). All patients were asked to complete body image scale (BIS), Beck depression inventory (BDI), and short form-36 (SF-36). There were no differences between groups with regard to demographic variables (p>0.05). Mean VAS was 7.5±1.4 for the patients with FMS and 0.3±0.4 for control subjects (p<0.05). Mean FIQ was 70.8±13.2 and 8.2±9.6 for the FMS and control groups, respectively (p<0.05). Mean BIS and BDI were 106.5±24.0 and 20.2±11.2 for FMS group and 66.3±23.4 and 3.4±4.0 for control group, respectively (p<0.05). SF-36 subscores were found to be significantly lower in patients with FMS than control subjects (p<0.05), except for the social function subscore. BIS score had significant relationships both with VAS (r=0.843) and FIQ (r=0.290) in patients with FMS (p<0.05). There were significant relationships between BIS scores and SF-36 pain (r=?-0.288), energy/vitality (r=?-0.519), mental health (r=?-0.442), and general health (r=?-0,492) subscores (p<0.05). Body image was associated with VAS in the multivariate linear regression analysis. The results of the present study indicate that body image is disturbed in patients with FMS compared to control subjects. For the evaluation of the level of pain, impact of the disease, and QoL in patients with FMS, it would be useful to consider the relationship of the body image disturbance with these parameters.     

The relationship between serum antioxidant vitamins,magnesium levels,and clinical parameters in patients with primary fibromyalgia syndrome

We proposed to assess serum antioxidant vitamins and magnesium (Mg) levels in patients with fibromyalgia (FM) in comparison to healthy controls. Additionally, the association between the serum antioxidant vitamins, magnesium levels, and clinical parameters in FM patients was also investigated. Forty female patients, aged between 30 and 50 years, were diagnosed with FM according to ACR-1990 criteria, and 40 healthy controls were included in the present study. Socio-demographic characteristics of participants, accompanying symptoms, and number of tender points (TP) of the patients were recorded. The intensity of pain was measured using the visual analogue scale (VAS). The functional status and depression levels were evaluated with Fibromyalgia Impact Questionnaire (FIQ) and Beck Depression Inventory (BDI), respectively. Serum vitamins A, C, and E and Mg levels were measured. There were no significant differences in the levels of vitamins A, C, and E and Mg between control subjects and patients with fibromyalgia (p > 0.05). In addition, no statistically significant correlations were found between mean levels of serum vitamins A, C, and E, and Mg and number of TP, scores of VAS, FIQ, and BDI in patients with FM (p > 0.05). According to the results of this study, it was asserted that other complex mechanism may play an important role in the pathophysiology of FM without plasma antioxidant vitamins and Mg levels.     

More pain,more tender points: is fibromyalgia just one end of a continuous spectrum?

OBJECTIVES: To investigate the hypothesis that fibromyalgia represents one end of a spectrum in which there is a more general association between musculoskeletal pain and tender points. METHODS: The subjects studied were 177 individuals selected from a population based screening survey for musculoskeletal pain. All subjects completed a pain mannikin and were examined for the presence of tender points at the nine American College of Rheumatology bilateral sites. RESULTS: There were moderately strong associations (odds ratios range 1.3-3.1) between the reported presence of pain in a body segment and the presence of a tender point within that segment. Further, there was evidence of a trend of increasing number of tender points with increasing number of painful segments. The reporting of non-specific pain, aching, or stiffness, was also associated with high tender point counts. CONCLUSION: This study illustrates that the association between tender points and pain is not restricted to the clinically defined subgroup with chronic widespread pain. Given that widespread pain and tender points have previously been linked with distress, this might reflect lesser degrees, or earlier phases of the somatisation of distress.     

Predictors of clinical pain intensity in patients with fibromyalgia syndrome

Central changes in pain processing have been previously reported in patients with fibromyalgia syndrome. These changes include decreased thresholds to mechanical and thermal stimuli (allodynia) and central sensitization, both of which are fundamental to the generation of clinical pain. Therefore, psychophysical measures of central pain processing may be useful predictors of clinical pain intensity of fibromyalgia syndrome patients. Previous studies of fibromyalgia syndrome patients have shown statistically significant correlations of psychophysical test results with clinical pain intensity. The tests used to characterize this important relationship were dependent on spinal cord pain mechanisms and included temporal summation of pain or wind-up and wind-up after-sensations. Particularly, the magnitude of wind-up after-sensations appeared to be one of the best predictors for clinical pain intensity of fibromyalgia syndrome patients (27%). Furthermore, the combination of tender point count, negative affect, and wind-up aftersensations accounted for approximately 50% of the variance in clinical pain intensity of fibromyalgia syndrome patients. Therefore, wind-up after-sensations, tender point count, and negative affect not only seem to represent relevant pain mechanisms but also strongly emphasize their importance for fibromyalgia syndrome pain.