Antonio Collado

Hyperexcitable C nociceptors in fibromyalgia

To test the hypothesis that peripheral C nociceptor function may be abnormal in fibromyalgia and that C nociceptor dysfunction may contribute to the symptoms reported by these patients.

Documento de consenso sobre el diagnóstico y tratamiento de la fibromialgia en Cataluña

La fibromialgia (FM) es una enfermedad cronica y compleja que provoca dolores extensos que pueden llegar a ser invalidantes, y afecta a la esfera biologica, psicologica y social del paciente. La FM es un problema de salud dada su elevada prevalencia y morbilidad, su alto indice de frecuentacion y el elevado consumo de recursos sanitarios que provoca 1 . El Pla de Salut de Catalunya 1996-1998 ya recoge este problema, fruto del cual se elaboraron unos Criterios Comunes Minimos para la Atencion de Enfermos con Fibromialgia. Debido a la evolucion de los conocimientos que ha acontecido en los ultimos anos y a la confirmacion de su alta prevalencia y morbilidad, se ha constituido un grupo de trabajo multidisciplinario con la voluntad de redactar un documento orientativo, a modo de guia de practica clinica, que estructure y homogeneice los conceptos y actitudes que se pueden aplicar a estos pacientes.

Increased glutamate/glutamine compounds in the brains of patients with fibromyalgia: a magnetic resonance spectroscopy study.

OBJECTIVE Fibromyalgia (FM) has been defined as a systemic disorder that is clinically characterized by pain, cognitive deficit, and the presence of associated psychopathology, all of which are suggestive of a primary brain dysfunction. This study was undertaken to identify the nature of this cerebral dysfunction by assessing the brain metabolite patterns in patients with FM through magnetic resonance spectroscopy (MRS) techniques. METHODS A cohort of 28 female patients with FM and a control group of 24 healthy women of the same age were studied. MRS techniques were used to study brain metabolites in the amygdala, thalami, and prefrontal cortex of these women. RESULTS In comparison with healthy controls, patients with FM showed higher levels of glutamate/glutamine (Glx) compounds (mean +/- SD 11.9 +/- 1.6 arbitrary units [AU] versus 13.4 +/- 1.7 AU in controls and patients, respectively; t = 2.517, 35 df, corrected P = 0.03) and a higher Glx:creatine ratio (mean +/- SD 2.1 +/- 0.4 versus 2.4 +/- 1.4, respectively; t = 2.373, 35 df, corrected P = 0.04) in the right amygdala. In FM patients with increased levels of pain intensity, greater fatigue, and more symptoms of depression, inositol levels in the right amygdala and right thalamus were significantly higher. CONCLUSION The distinctive metabolic features found in the right amygdala of patients with FM suggest the possible existence of a neural dysfunction in emotional processing. The results appear to extend previous findings regarding the dysfunction in pain processing observed in patients with FM.

HLA class II antigens (DR, DQ loci) and peripheral arthritis in ankylosing spondylitis.

Fifty one patients with ankylosing spondylitis (AS) were typed for HLA-A, B, C, DR, and DQ antigens. The antigen frequencies were compared with those of a normal population and with a B27 positive control group. All but one of the patients with AS were HLA-B27 positive. A positive linkage disequilibrium between Cw1, Cw2, DR1, and the B27 antigen was observed. Patients with AS showed a significant increase in DQw2 antigen compared with the B27 positive control group. No differences in antigenic frequencies were observed in patients having peripheral arthritis and patients with only axial involvement. Seven out of nine patients (78%) with an erosive peripheral arthritis were DR7 positive, suggesting that DR7 or genes closely linked could be related with a more aggressive peripheral joint involvement in patients with AS.

Personality does not distinguish people with fibromyalgia but identifies subgroups of patients

OBJECTIVES The objectives were to compare the personality of fibromyalgia (FM) patients with other chronic painful and nonpainful disorders considering the confusion due to psychopathology and to assess the clustering of FM patients according to their personality profile. METHODS Differences in the NEO Five-Factor Inventory between FM, non-FM chronic pain and drug-resistant epileptic patients were assessed including the confounding effect of demographics and psychopathological status by multivariate regression analysis. Clustering of FM patients was assessed by two-step cluster analysis. Differences in clinical severity and psychosocial problems between subgroups and their outcome 6 months after multidisciplinary treatment were assessed. RESULTS The final sample comprised 874 patients. Once the effect of confounding variables was considered, clinically nonsignificant differences in personality were observed between groups. FM patients could, however, be grouped into two clusters. Cluster 1 was characterized by higher neuroticism and lower extraversion and showed a worse pretreatment clinical state including more psychosocial problems. In spite of having reached a wider general improvement at 6-month follow-up, Cluster 1 patients remained more anxious and depressed. CONCLUSIONS Identifying personality-based subgroups of FM might allow implementing specific preventive strategies. FM treatment might be optimized by increasing medication compliance, improving therapeutic alliance and testing different therapeutic options and treatment sequencing for each personality subgroup.

Pain locus of control predicts return to work among Spanish fibromyalgia patients after completion of a multidisciplinary pain program.

OBJECTIVE To assess the influence of the pain locus of control on return to work in fibromyalgia patients. METHODS Ninety-eight fibromyalgia patients on sick leave were enrolled in a multidisciplinary treatment program and were followed up for 12 months post-discharge. Treatment was considered successful at discharge in the case of patients who returned to work and unsuccessful in patients who remained sick listed. Treatment was considered successful during follow-up in patients who remained at work for at least the last 6 months of follow-up. Patients who took sick leave again and those lost to follow-up were considered failures. Logistic regression methods were used to define the best predictive models of treatment failure. RESULTS Fifty-eight patients were considered treatment successes at discharge and 50 at 12-month follow-up. The subscale Fate from the Multidimensional Health Locus of Control-Pain Scale and the Health Assessment Questionnaire predicted treatment failure at discharge (-2lnR=57.79; chi-square=74.74; df=2; P<.001). The predictive model of treatment failure at 12-month follow-up was unspecific. CONCLUSION Fibromyalgia patients undergoing a multidisciplinary treatment who were least likely to return to work at discharge were those with a pain locus of control characterized by more negative expectations about pain progression and a high perceived functional disability.

Immunoglobulin A in the skin of patients with ankylosing spondylitis.

Cutaneous immunofluorescence studies were carried out in 21 patients with ankylosing spondylitis (AS) and the results compared with those for 18 healthy subjects. The most prominent finding was the presence of IgA in dermal vessels of patients with AS (71% compared with 17% of the control group). IgG and IgM cutaneous deposits were also observed in patients with AS, but these results did not differ from those of the control group. A renal biopsy was performed in three of the patients presenting with unexplained microscopic haematuria. One of them had an IgA nephropathy, but no correlation was found between kidney and skin deposits of IgA. These findings suggest that IgA cutaneous deposits in AS are not a marker of IgA nephropathy but stress the role of immunoglobulin A in the pathogenesis of this disease.

The Symptom Checklist-Revised (SCL-90-R) is able to discriminate between simulation and fibromyalgia.

This study assessed the ability of the Symptom Checklist-Revised (SCL-90-R) to discriminate between two groups of fibromyalgia patients (those who were about to begin a treatment including the explicit aim of returning to work and those who were initiating a legal procedure to obtain permanent disability compensation) and two groups of healthy volunteers (medical students and psychology graduates), who were asked to produce a symptomatic resemblance to a chronic pain disorder. Logistic regression analyses were applied to the SCL-90-R subscales and individual probabilistic indices of simulation were calculated. Results showed that the SCL-90-R was able to discriminate between healthy subjects and both groups of patients with a high sensitivity and specificity. The individual indices of simulation, which might be more useful in clinical practice than the comparison of the SCL-90-R profiles, also showed an appropriate level of accuracy.

Work, family and social environment in patients with Fibromyalgia in Spain: an epidemiological study: EPIFFAC study

AbstractBackgroundFibromyalgia (FM) is a condition characterized by widespread pain, estimated to affect 2.4% of the Spanish population. Nowadays, there are no consistent epidemiological studies on the actual impact of the disease on work and family of these patients in a representative manner; therefore, the purpose of the study is to analyze the impact on family, employment and social environment in a representative sample of patients with FM attending Primary Public Care Centers in Spain.MethodsWe carried out an epidemiological study, with a probability sampling procedure, stratified, relative to the municipality size and the number of health centres, seeking territorial representation. The survey was conducted using a self-administered structured questionnaire.ResultsA sample of 325 patients with FM was studied in 35 Primary Health Care Centers (PHCCs). The sample is composed of 96.6% of women, 51.9 (8) years of mean (standard deviation- sd) age. Ninety-three percent of the patients have worked throughout their life. Mean (sd) age onset of symptoms was 37 (11) years and diagnosis of FM was established 6.6 (8) years later. Family Environment: Fifty-nine percent of patients have difficulties with their partner. Forty-four percent of the patients report to be fairly or totally dependent on a family member in household chores. The household income decreased a mean (sd) of 708 (504) Euros/month in 65% of the patients. In 81% of the patients, there was an increase in extra expenses related to the disease with a mean (sd) of 230 (192) Euros/month. Working environment: At the moment of the study, 45% of the patients had work activity (34% were working and 11% were at sick leave), 13% were unemployed seeking job and 42% were not in the labor force. Twenty-three percent of patients had some degree of permanent work disability pension. Social Environment: The degree of satisfaction with health care professionals was low and twenty-six percent of the patients were members of specific patients associations.ConclusionsThis study finds that people with FM who visit PHCCs of Spain experience a high impact on families and employment with heavy loss of ability to work.

OP0067 Cluster analysis of clinical data identifies fibromyalgia subgroups

Background Fibromyalgia (FM) is characterized by widespread pain and other symptoms, such as psychiatric and physical comorbidities. The heterogeneity of FM hinders its assessment and management. Objectives The aim of this work is to identify FM subgroups by classifying clinical data into simplified dimensions. Methods 44 variables were evaluated in 560 unrelated Spanish FM cases of Caucasian origin. All participants fulfilled 1990 ACR FM criteria and were evaluated at one of five Rheumatology Units. A partitioning analysis was performed to find groups of variables similar to each other, thus describing underlying FM dimensions. Given the mixed nature type of the variables, these were transformed into binary types (0=mild; 1=severe), and a generalization of the Gower method was applied to find similarities between variables. A score was constructed per sample and dimension based on the weights of the variables depicting the specific dimension. Kmeans clustering procedure was then applied into resulting scores to create FM subgroups. This analysis was also performed in a replication set of 950 cases. Results Variables clustered into three independent dimensions: pain and other symptoms, family and personal comorbidities and clinical scales (fig. 1). Only the two most reliable dimensions (pain and other symptoms and comorbidities) were considered for FM subgroups construction. Resulting scores classified FM samples into three subgroups: high symptomatology and comorbidities, high symptomatology but low comorbidities and low symptomatology and comorbidities. Both the variable clustering and the sample subgrouping were replicated in the second cohort. Figure 1. Clustering of variables. The variables included in each dimension are listed and sorted by their weighted contribution. Conclusions We have identified three subgroups of FM samples in a large cohort of FM by clustering clinical data. This partitioning method could be used as a useful tool in FM severity assessment and personalized treatment. Disclosure of Interest None Declared