Fibromyalgia Fatigue Research Articles

Fibromyalgia and Fatigue: Central Processing, Widespread Dysfunction

Abstract Biological and psychological bases for the covariation of pain and fatigue in fibromyalgia (FM) are reviewed. FM is characterized as a disorder of central sensitization, with pain and fatigue as the most prominent symptoms. The roles of sleep disturbance and affective dysregulation as both precipitants and consequences of pain and fatigue in FM are discussed. It is argued that a positive affective disturbance may uniquely characterize pain and fatigue symptoms in FM. Finally, pharmacological and nonpharmacological treatments for FM are highlighted, with an emphasis on the efficacy of these treatments in alleviating pain and fatigue symptoms.

Central motor control failure in fibromyalgia: a surface electromyography study

BackgroundFibromyalgia (FM) is characterised by diffuse musculoskeletal pain and stiffness at multiple sites, tender points in characteristic locations, and the frequent presence of symptoms such as fatigue. The aim of this study was to assess whether the myoelectrical manifestations of fatigue in patients affected by FM are central or peripheral in origin.MethodsEight female patients aged 55.6 ± 13.6 years (FM group) and eight healthy female volunteers aged 50.3 ± 9.3 years (MCG) were studied by means of non-invasive surface electromyography (s-EMG) involving a linear array of 16 electrodes placed on the skin overlying the biceps brachii muscle, with muscle fatigue being evoked by means of voluntary and involuntary (electrically elicited) contractions. Maximal voluntary contractions (MVCs), motor unit action potential conduction velocity distributions (mean ± SD and skewness), and the mean power frequency of the spectrum (MNF) were estimated in order to assess whether there were any significant differences between the two groups and contraction types.ResultsThe motor pattern of recruitment during voluntary contractions was altered in the FM patients, who also showed fewer myoelectrical manifestations of fatigue (normalised conduction velocity rate of changes: -0.074 ± 0.052%/s in FM vs -0.196 ± 0.133%/s in MCG; normalised MNF rate of changes: -0.29 ± 0.16%/s in FM vs -0.66 ± 0.34%/s in MCG). Mean conduction velocity distribution and skewnesses values were higher (p < 0.01) in the FM group. There were no between-group differences in the results obtained from the electrically elicited contractions.ConclusionThe apparent paradox of fewer myoelectrical manifestations of fatigue in FM is the electrophysiological expression of muscle remodelling in terms of the prevalence of slow conducting fatigue-resistant type I fibres. As the only between-group differences concerned voluntary contractions, they are probably more related to central motor control failure than muscle membrane alterations, which suggests pathological muscle fibre remodelling related to altered suprasegmental control.

Autonomic dysfunction in fibromyalgia syndrome: Postural orthostatic tachycardia

Although fibromyalgia (FM) syndrome is defined by chronic widespread pain and tenderness, additional symptoms, including disabling fatigue and dizziness, are often reported by patients with this chronic illness. Although nonrestorative sleep may play an important role for chronic fatigue in FM, other mechanisms, including dysfunction of the autonomic nervous system (ANS), need to be considered. Many important biological functions, such as heart rate, blood pressure, respirations, and bowel function, are tightly regulated by the ANS. However, dysfunction of the ANS is common in FM and often becomes quite apparent after positional changes from supine to upright. Although such positional changes sometimes result in syncope, they are more often associated with palpitations and dizziness. Head-up tilt table testing can be used to evaluate autonomic dysfunction and is frequently helpful for the work-up of FM complaints, including fatigue, dizziness, and palpitations. One of the most common events experienced by FM patients during tilt table testing is postural orthostatic tachycardia syndrome, which is defined as a heart rate increase of more than 30 beats per minute after more than 3 minutes of standing upright.

NO-mediated alterations in skeletal muscle nutritive blood flow and lactate metabolism in fibromyalgia

The purpose of these investigations was to determine if differences exist in skeletal muscle nutritive blood flow and lactate metabolism in women with fibromyalgia (FM) compared to healthy women (HC); furthermore, to determine if differences in nitric oxide-mediated systems account for any detected alterations in blood flow and lactate metabolism and contribute to exertional fatigue in FM. FM ( n=8) and HC ( n=8) underwent a cycle ergometry test of aerobic capacity, a muscle biopsy for determination of nitric oxide synthase (eNOS, nNOS, iNOS) content, and microdialysis for investigation of muscle nutritive blood flow and lactate metabolism. During prolonged (3 h) resting conditions, the ethanol outflow/inflow ratio (inversely related to blood flow) increased in FM over time compared to HC ( P<0.05). FM also exhibited a reduced nutritive blood flow response to aerobic exercise ( P<0.05). There was an increase in dialysate lactate in response to acetylcholine in FM, and to sodium nitroprusside in both groups, with a greater rise in dialysate lactate in FM ( P<0.05). The iNOS protein content was higher in FM and was negatively correlated with total exercise time ( r 2=0.462, P<0.05). In conclusion: (1) There is reduced nutritive flow response to aerobic exercise and reduced maximal exercise time in FM that might relate to higher iNOS protein content and contribute to exertional fatigue in FM; (2) The increased dialysate lactate in FM in response to stimulation of NOS or a nitric oxide donor suggest that FM may be more sensitive than HC to the suppressive effect of nitric oxide on oxidative phosphorylation.

Breastfeeding in chronic illness: the voices of women with fibromyalgia.

To describe what it is like for women with fibromyalgia (FM) to breastfeed their infants. Nine women with FM who chose to breastfeed their infants were the sample for this qualitative study. van Manen's phenomenological method of reflection, writing, and rewriting was used to analyze the data collected through in-depth tape-recorded interviews and written stories. All nine women felt that they were not successful in their attempts to breastfeed, and felt frustrated. Themes included (a) muscle soreness, pain, and stiffness made it difficult to breastfeed the baby; (b) fatigue interfered with the breastfeeding process; (c) the need for medication, perceived insufficient milk supply, and sore nipples led to forced unplanned weaning; and (d) being forced to wean the infant when not ready to do so created sadness and a feeling of depression. Nurses who work with women with FM who choose to breastfeed need to be proactive in providing informational, emotional, and physical support to facilitate a successful breastfeeding experience for these women. Knowing that the pain, muscle soreness, stiffness, and fatigue of FM may affect breastfeeding can direct nurses to help women with FM plan for support after childbirth and learn techniques to control/reduce the muscle pain and stiffness. Nurses are encouraged to refer breastfeeding women with FM to lactation consultants and support groups for encouragement and validation regarding their concerns about breastfeeding. It is important that nurses continue to serve as advocates for breastfeeding women with FM and keep other healthcare providers informed about the issues related to breastfeeding for women with FM.

PAIN IN FIBROMYALGIA

Just as our caveman forebears were frail in the face of predatory animals, we are frail in today's society of childhood neglect or abuse, bumper-to-bumper traffic, frustration at work, and multiple daily hassles. The same neuroendocrine systems and pain regulatory mechanisms that protected early man during acute stress are still encoded in our genome, but may be maladaptive in psychologically and physiologically vulnerable people faced with chronic stress. Many patients with fibromyalgia become vulnerable because of the long-lasting psychological and neurophysiological effects of negative experiences in childhood. Ill-equipped with positive cognitive, emotional, and behavioral skills as adults, they display maladaptive coping strategies, low self-efficacy, and negative mood when confronted with the inevitable stressors of life. Psychological distress ensues, which reduces thresholds for pain perception and tolerance (already relatively low in women) even further. Converging lines of psychological and neurobiological evidence strongly suggest that chronic stress-related blunting of the HPA, sympathetic, and other axes of the stress response together with associated alterations in pain regulatory mechanisms may finally explain the pain and fatigue of fibromyalgia. Vulnerable people who can be classified by the ACR criteria as having fibromyalgia do not have a discrete disease. They are simply the most ill in a continuum of distress, chronic pain, and painful tender points in the general population.