Does pain in fibromyalgia reflect somatization?

A retrospective observational study comparing somatosensory amplification in fibromyalgia, chronic pain, psychiatric disorders and healthy subjects

OBJECTIVES

Somatosensory amplification (SA) has been described as an important feature of somatoform disorders, and an "amplifying somatic style" has been reported as a negative connotation of body perception. As widespread pain (WSP) in fibromyalgia (FM) is due to a central sensitization (CS) rather than organic alterations, there has been discussion as to whether FM is equivalent to or distinct from somatization disorder (SD). Assuming SD and FM are two distinct entities, an increase in somatic amplification should be expected only in subjects who have SD, regardless of the type of pain they experience. Purpose of the study was to explore the magnitude of SA in FM, and whether this depends on the association with SD.

METHODS

FM (n=159) other forms of chronic pain (OCP, n=582), psychiatric (Psy, n=53) and healthy (H, n=55) subjects were investigated using the Somatosensory Amplification Scale (SSAS), Illness Behavior Questionnaire, (IBQ), Italian Pain Questionnaire (IPQ), and Cold Pressor Test (CPT) in a retrospective observational study.

RESULTS

FM subjects displayed higher SSAS scores than the other groups. High SSAS score was associated with FM (OR=8.39; 95%CI: 5.43-12.46) but not OCP. Although FM has the highest prevalence of SD (x²=14.07; p=.007), high SSAS scores were associated with SD in OCP but not in FM.

CONCLUSIONS

Unlike in OCP, in FM high SSAS scores were independent of the presence of SD. From a biopsychosocial perspective, SSAS may be a factor associated with the onset of FM.

Association between childhood trauma and loss of functionality in adult women with fibromyalgia

OBJECTIVE: To investigate whether history of childhood trauma is associated with loss of functionality in adult women with fibromyalgia (FM). A secondary objective was to assess the presence of differences between depressed and non-depressed adult women with FM in a regression model for functionality. METHODS: A total of 114 adult women with FM according to the American College of Rheumatology diagnostic criteria answered the Childhood Trauma Questionnaire and the Fibromyalgia Impact Questionnaire. All subjects were interviewed by trained psychiatrists and evaluated for depression using the Mini International Neuropsychiatric Interview (MINI) - Brazilian version 5.0.0. Correlation and regression models were used to investigate associations between childhood trauma and loss of functionality among patients with FM. The sample was stratified by presence and absence of clinical depression. RESULTS: Overall, childhood trauma was associated with of loss of functionality in adult women with FM. When stratified by depression, the regression model significantly increased the association among non-depressed patients, even after adjustment for age and use of psychotropic medications. CONCLUSIONS: Childhood trauma showed a clinically important association with loss of functionality among adult women with FM. The associations were more pronounced among subjects without comorbid depression.

The clinical concept of fibromyalgia as a changing paradigm in the past 20 years

Fibromyalgia (FMS) is a valid clinical condition that affects 2%–4% of the population with a pivot symptom of widespread body pain. The cause and cure of FMS are as yet unknown. The concept of FMS has evolved over the past two decades to incorporate symptoms beyond pain as contributing to the global spectrum of suffering. FMS is now recognized to be grounded in the neurological domain with evidence of dysregulation of pain processing. Appreciation of the neurophysiologic mechanisms operative in FMS has contributed to rational treatment recommendations, although a “gold standard treatment” does not currently exist. Ideal treatments for FMS patients should be individualized with emphasis on active patient participation, good health practices, and multimodal intervention, incorporating nonpharmacologic and pharmacologic treatments. Predictors of outcome, which is favourable in over 50% of patients, are unknown, but those with better outcome do more physical activity and use fewer medications.

Social influences on the concept of fibromyalgia

Despite relevant evidence of physical illness promoting fibromyalgia syndrome (FMS), some authors claim that it is a psychological illness, or due to "psychological amplification." Good evidence for such views is lacking. Selection processes lead to increased rates of psychological illness in general practice and in specialist practice. The physical distress of FMS can increase both anxiety and depression. Questionable research supported by the insurance industry has tended to provide negative and disparaging views of pain. Current imaging studies support the view that central effects connected with FMS relate to the processing of noxious stimulation more than affective disorder.

Biology and therapy of fibromyalgia: pain in fibromyalgia syndrome

Fibromyalgia (FM) pain is frequent in the general population but its pathogenesis is only poorly understood. Many recent studies have emphasized the role of central nervous system pain processing abnormalities in FM, including central sensitization and inadequate pain inhibition. However, increasing evidence points towards peripheral tissues as relevant contributors of painful impulse input that might either initiate or maintain central sensitization, or both. It is well known that persistent or intense nociception can lead to neuroplastic changes in the spinal cord and brain, resulting in central sensitization and pain. This mechanism represents a hallmark of FM and many other chronic pain syndromes, including irritable bowel syndrome, temporomandibular disorder, migraine, and low back pain. Importantly, after central sensitization has been established only minimal nociceptive input is required for the maintenance of the chronic pain state. Additional factors, including pain related negative affect and poor sleep have been shown to significantly contribute to clinical FM pain. Better understanding of these mechanisms and their relationship to central sensitization and clinical pain will provide new approaches for the prevention and treatment of FM and other chronic pain syndromes.

La fibromialgia y su diagnóstico

Fibromyalgia or fibromyalgic syndrome (FMS) is a clinical picture of unknown origin that is characterized by generalized, incapacitating and chronic pain together with the demonstration in the physical examination of previously defined points in which moderate pressure causes pain, called fibromyalgia tender points (FTP). FMS lacks objective, analytic imaging or pathological data, so that its diagnosis is based exclusively on subjective data, such as that the pain reported by the patient and the pain caused by the FTP pressure. Although the fibromyalgia classification criteria of the American College of Rheumatology are not diagnostic criteria, they have been extensively used to diagnose FMS in patients with chronic diffuse arthromyalgias. Fibromyalgia diagnosis reduces the patient's anxiety, avoiding complementary expensive and unnecessary tests and it allows the patient to share his/her fears, illnesses and expectations with other human beings who suffer the same problem.