Fibromyalgia is a common illness characterized by chronic widespread pain, sleep problems (including unrefreshing sleep), physical exhaustion and cognitive difficulties. The definition, pathogenesis and treatment are controversial, and some even contest the existence of this disorder. In 1990, the American College of Rheumatology (ACR) defined classification criteria that required multiple tender points (areas of tenderness occurring in muscles and muscle-tendon junctions) and chronic widespread pain. In 2010, the ACR preliminary diagnostic criteria excluded tender points, allowed less extensive pain and placed reliance on patient-reported somatic symptoms and cognitive difficulties. Fibromyalgia occurs in all populations worldwide, and symptom prevalence ranges between 2% and 4% in the general population. The prevalence of people who are actually diagnosed with fibromyalgia ('administrative prevalence') is much lower. A model of fibromyalgia pathogenesis has been suggested in which biological and psychosocial variables interact to influence the predisposition, triggering and aggravation of a chronic disease, but the details are unclear. Diagnosis requires the history of a typical cluster of symptoms and the exclusion of a somatic disease that sufficiently explains the symptoms by medical examination. Current evidence-based guidelines emphasize the value of multimodal treatments, which encompass both non-pharmacological and selected pharmacological treatments tailored to individual symptoms, including pain, fatigue, sleep problems and mood problems. For an illustrated summary of this Primer, visit: http://go.nature.com/LIBdDX.

The growing number of studies indicates increasing interest in the WHODAS 2.0 for assessing individual functioning and disability in different settings and individual health conditions. The WHODAS 2.0 shows strong correlations with several other measures of activity limitations; probably due to the fact that it shares the same disability latent variable with them. Implications for Rehabilitation WHODAS 2.0 seems to be a valid, reliable self-report instrument for the assessment of disability. The increasing interest in use of the WHODAS 2.0 extends to rehabilitation and life sciences rather than being limited to psychiatry. WHODAS 2.0 is suitable for assessing health status and disability in a variety of settings and populations. A critical issue for rehabilitation is that a single "minimal clinically important .difference" score for the WHODAS 2.0 has not yet been established.

In the last decade, there has been burgeoning interest in the effectiveness of third-generation psychological therapies for managing fibromyalgia (FM) symptoms. The present study examined the effectiveness of acceptance and commitment therapy (ACT) on functional status as well as the role of pain acceptance as a mediator of treatment outcomes in FM patients. A total of 156 patients with FM were enrolled at primary health care centers in Zaragoza, Spain. The patients were randomly assigned to a group-based form of ACT (GACT), recommended pharmacological treatment (RPT; pregabalin + duloxetine), or wait list (WL). The primary end point was functional status (measured with the Fibromyalgia Impact Questionnaire, FIQ). Secondary end points included pain catastrophizing, pain acceptance, pain, anxiety, depression, and health-related quality of life. The differences between groups were calculated by linear mixed-effects (intention-to-treat approach) and mediational models through path analyses. Overall, GACT was statistically superior to both RPT and WL immediately after treatment, and improvements were maintained at 6months with medium effect sizes in most cases. Immediately after treatment, the number needed to treat for 20% improvement compared to RPT was 2 (95% confidence interval 1.2-2.0), for 50% improvement 46, and for achieving a status of no worse than mild impaired function (FIQ total score <39) also 46. Unexpectedly, 4 of the 5 tested path analyses did not show a mediation effect. Changes in pain acceptance only mediated the relationship between study condition and health-related quality of life. These findings are discussed in relation to previous psychological research on FM treatment.

No abstract

No abstract

No abstract

The objective of the present study was to examine the dimensionality, reliability, and construct validity of the Five Facet Mindfulness Questionnaire (FFMQ) in three Spanish samples using structural equation modeling (SEM). Pooling the FFMQ data from 3 Spanish samples (n = 1191), we estimated the fit of two competing models (correlated five-factor vs. bifactor) via confirmatory factor analysis. The factorial invariance of the best fitting model across meditative practice was also addressed. The pattern of relationships between the FFMQ latent dimensions and anxiety, depression, and distress was analyzed using SEM. FFMQ reliability was examined by computing the omega and omega hierarchical coefficients. The bifactor model, which accounted for the covariance among FFMQ items with regard to one general factor (mindfulness) and five orthogonal factors (observing, describing, acting with awareness, non-judgment, and non-reactivity), fit the FFMQ structure better than the correlated five-factor model. The relationships between the latent variables and their manifest indicators were not invariant across the meditative experience. Observing items had significant loadings on the general mindfulness factor, but only in the meditator sub-sample. The SEM analysis revealed significant links between mindfulness and symptoms of depression and stress. When the general factor was partialled out, the acting with awareness facet did not show adequate reliability. The FFMQ shows a robust bifactor structure among Spanish individuals. Nevertheless, the Observing subscale does not seem to be adequate for assessing mindfulness in individuals without meditative experience.

Fibromyalgia (FM) syndrome represents a great challenge for clinicians and researchers because the efficacy of currently available treatments is limited. This study examined the efficacy of mindfulness-based stress reduction (MBSR) for reducing functional impairment as well as the role of mindfulness-related constructs as mediators of treatment outcomes for people with FM. Two hundred twenty-five participants with FM were randomized into 3 study arms: MBSR plus treatment-as-usual (TAU), FibroQoL (multicomponent intervention for FM) plus TAU, and TAU alone. The primary endpoint was functional impact (measured with the Fibromyalgia Impact Questionnaire Revised), and secondary outcomes included “fibromyalginess,” anxiety and depression, pain catastrophising, perceived stress, and cognitive dysfunction. The differences in outcomes between groups at post-treatment assessment (primary endpoint) and 12-month follow-up were analyzed using linear mixed-effects models and mediational models through path analyses. Mindfulness-based stress reduction was superior to TAU both at post-treatment (large effect sizes) and at follow-up (medium to large effect sizes), and MBSR was also superior to FibroQoL post-treatment (medium to large effect sizes), but in the long term, it was only modestly better (significant differences only in pain catastrophising and fibromyalginess). Immediately post-treatment, the number needed to treat for 20% improvement in MBSR vs TAU and FibroQoL was 4.0 (95% confidence interval [CI] = 2.1-6.5) and 5.0 (95% CI = 2.7-37.3). An unreliable number needed to treat value of 9 (not computable 95% CI) was found for FibroQoL vs TAU. Changes produced by MBSR in functional impact were mediated by psychological inflexibility and the mindfulness facet acting with awareness. These findings are discussed in relation to previous studies of psychological treatments for FM.