Tag: pain

Cold pressor pain sensitivity in monozygotic twins discordant for chronic fatigue syndrome

Abstract:

OBJECTIVE: Individuals with chronic fatigue syndrome (CFS) experience many pain symptoms. The present study examined whether pain and fatigue ratings and pain threshold and tolerance levels for cold pain differed between twins with CFS and their cotwins without CFS.

DESIGN: Cotwin control design to assess cold pain sensitivity, pain, and fatigue in monozygotic twins discordant for CFS.

PATIENTS AND SETTING: Fifteen monozygotic twin pairs discordant for CFS recruited from the volunteer Chronic Fatigue Twin Registry at the University of Washington.

RESULTS: Although cold pain threshold and tolerance levels were slightly lower in twins with CFS than their cotwins without CFS, these differences failed to reach statistical significance. Subjective ratings of pain and fatigue at multiple time points during the experimental protocol among twins with CFS were significantly higher than ratings of pain (P = 0.003) and fatigue (P < 0.001) by their cotwins without CFS.

CONCLUSIONS: These results, while preliminary, highlight the perceptual and cognitive components to the pain experience in CFS. Future studies should focus on examining the heritability of pain sensitivity and the underlying mechanisms involved in the perception of pain sensitivity in CFS.

 

Source: Ullrich PM, Afari N, Jacobsen C, Goldberg J, Buchwald D. Cold pressor pain sensitivity in monozygotic twins discordant for chronic fatigue syndrome. Pain Med. 2007 Apr;8(3):216-22. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2957294/ (Full article)

 

Central sensitization: a biopsychosocial explanation for chronic widespread pain in patients with fibromyalgia and chronic fatigue syndrome

Abstract:

In addition to the debilitating fatigue, the majority of patients with chronic fatigue syndrome (CFS) experience chronic widespread pain. These pain complaints show the greatest overlap between CFS and fibromyalgia (FM). Although the literature provides evidence for central sensitization as cause for the musculoskeletal pain in FM, in CFS this evidence is currently lacking, despite the observed similarities in both diseases. The knowledge concerning the physiological mechanism of central sensitization, the pathophysiology and the pain processing in FM, and the knowledge on the pathophysiology of CFS lead to the hypothesis that central sensitization is also responsible for the sustaining pain complaints in CFS.

This hypothesis is based on the hyperalgesia and allodynia reported in CFS, on the elevated concentrations of nitric oxide presented in the blood of CFS patients, on the typical personality styles seen in CFS and on the brain abnormalities shown on brain images. To examine the present hypothesis more research is required. Further investigations could use similar protocols to those already used in studies on pain in FM like, for example, studies on temporal summation, spatial summation, the role of psychosocial aspects in chronic pain, etc.

 

Source: Meeus M, Nijs J. Central sensitization: a biopsychosocial explanation for chronic widespread pain in patients with fibromyalgia and chronic fatigue syndrome. Clin Rheumatol. 2007 Apr;26(4):465-73. Epub 2006 Nov 18. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1820749/ (Full article)

 

Chronic musculoskeletal pain in patients with the chronic fatigue syndrome: a systematic review

Abstract:

BACKGROUND: In addition to debilitating fatigue the majority of patients with chronic fatigue syndrome (CFS) experience chronic widespread pain.

AIMS: Conducting a systematic review to critically assess the existing knowledge on chronic pain in CFS. We focussed on the definition, the prevalence and incidence, the aetiology, the relevance and the therapy strategy for chronic musculoskeletal pain and post-exertional pain in CFS.

METHODS: To identify relevant articles, we searched eight medical search engines. The search terms “chronic fatigue syndrome” AND “pain”, “nociception”, “arthralgia” and “myalgia”, were used to identify articles concerning pain in CFS. Included articles were reviewed by two blinded researchers.

RESULTS: Twenty-five articles and two abstract were identified and selected for further appraisal. Only 11 search results focussed on musculoskeletal pain in CFS patients. Regarding the standardized review of the articles, a 96% agreement between the researchers was observed. There is no consensus in defining chronic widespread pain in CFS, and although there is little or no strong proof for the exact prevalence, chronic pain is strongly disabling in CFS. Aetiological theories are proposed (sleep abnormalities, tryptophan, parovirus-B, hormonal and brain abnormalities and central sensitisation) and a reduction of pain threshold after exercise has been shown. Furthermore depression seemed not related to pain in CFS and a staphylococcus toxoid vaccine caused no significant pain reduction.

CONCLUSIONS: The results from the systematic review highlight the clinical importance of chronic pain in CFS, but only few studies addressing the aetiology or treatment of chronic pain in CFS are currently available.

 

Source: Meeus M, Nijs J, Meirleir KD. Chronic musculoskeletal pain in patients with the chronic fatigue syndrome: a systematic review. Eur J Pain. 2007 May;11(4):377-86. Epub 2006 Jul 13. https://www.ncbi.nlm.nih.gov/pubmed/16843021

 

Chronic musculoskeletal pain in chronic fatigue syndrome: recent developments and therapeutic implications

Abstract:

Patients with chronic fatigue syndrome (CFS) experience chronic musculoskeletal pain which is even more debilitating than fatigue. Scientific research data gathered around the world enables clinicians to understand, at least in part, chronic musculoskeletal pain in CFS patients. Generalized joint hypermobility and benign joint hypermobility syndrome appear to be highly prevalent among CFS sufferers, but they do not seem to be of any clinical importance.

On the other hand, pain catastrophizing accounts for a substantial portion of musculoskeletal pain and is a predictor of exercise performance in CFS patients. The evidence concerning pain catastrophizing is supportive of the indirect evidence of a dysfunctional pain processing system in CFS patients with musculoskeletal pain. CFS sufferers respond to incremental exercise with a lengthened and accentuated oxidative stress response, explaining muscle pain, postexertional malaise, and the decrease in pain threshold following graded exercise in CFS patients.

Applying the scientific evidence to the manual physiotherapy profession, pacing self-management techniques and pain neurophysiology education are indicated for the treatment of musculoskeletal pain in CFS patients. Studies examining the effectiveness of these strategies for CFS patients are warranted.

 

Source: Nijs J, Meeus M, De Meirleir K. Chronic musculoskeletal pain in chronic fatigue syndrome: recent developments and therapeutic implications. Man Ther. 2006 Aug;11(3):187-91. Epub 2006 Jun 14. https://www.ncbi.nlm.nih.gov/pubmed/16781183

 

The association between experimental and clinical pain measures among persons with fibromyalgia and chronic fatigue syndrome

Abstract:

Evoked or experimental pain is often used as a model for the study of clinical pain, yet there are little data regarding the relationship between the two. In addition, there are few data regarding the types of stimuli and stimulus intensities that are most closely related to clinical pain. In this study, 36 subjects with fibromyalgia (FM), chronic fatigue syndrome (CFS), or both syndromes were administered measures of clinical pain and underwent a dolorimetry evaluation. Subjects also underwent experimental pain testing utilizing heat and pressure stimulation.

Stimulation levels evoking low, moderate and high sensory intensity, and comparable levels of unpleasantness, were determined for both types of stimuli using random staircase methods. Clinical pain was assessed using visual analogue ratings and the short form of the McGill Pain Questionnaire (MPQ). Ratings of heat pain sensation were not significantly associated with clinical pain ratings, with the exception of unpleasantness ratings at high stimulus intensities. Pain threshold and tolerance as assessed by dolorimetry were significantly associated with average measures of clinical pain.

Both intensity and unpleasantness ratings of pressure delivered using random staircase methods were significantly associated with clinical pain at low, moderate and high levels, and the strength of the association was greater at increasingly noxious stimulus intensities. These findings suggest that random pressure stimulation as an experimental pain model in these populations more closely reflects the clinical pain for these conditions. These findings merit consideration when designing experimental studies of clinical pain associated with FM and CFS.

 

Source: Geisser ME, Gracely RH, Giesecke T, Petzke FW, Williams DA, Clauw DJ. The association between experimental and clinical pain measures among persons with fibromyalgia and chronic fatigue syndrome. Eur J Pain. 2007 Feb;11(2):202-7. Epub 2006 Mar 20. https://www.ncbi.nlm.nih.gov/pubmed/16546424

 

Chronic fatigue syndrome: assessment of increased oxidative stress and altered muscle excitability in response to incremental exercise

Abstract:

OBJECTIVES: Because the muscle response to incremental exercise is not well documented in patients suffering from chronic fatigue syndrome(CFS), we combined electrophysiological (compound-evoked muscle action potential, M wave), and biochemical (lactic acid production, oxidative stress) measurements to assess any muscle dysfunction in response to a routine cycling exercise.

DESIGN: This case-control study compared 15 CFS patients to a gender-, age- and weight-matched control group (n=11) of healthy subjects.

INTERVENTIONS: All subjects performed an incremental cycling exercise continued until exhaustion.

MAIN OUTCOME MEASURES: We measured the oxygen uptake (VO2), heart rate (HR), systemic blood pressure, percutaneous O2 saturation (SpO2), M-wave recording from vastus lateralis, and venous blood sampling allowing measurements of pH (pHv), PO2 (PvO2), lactic acid (LA), and three markers of the oxidative stress (thiobarbituric acid-reactive substances, TBARS, reduced glutathione, GSH, and ascorbic acid, RAA).

RESULTS: Compared with control, in CFS patients (i) the slope of VO2 versus work load relationship did not differ from control subjects and there was a tendency for an accentuated PvO2 fall at the same exercise intensity, indicating an increased oxygen uptake by the exercising muscles; (ii) the HR and blood pressure responses to exercise did not vary; (iii) the anaerobic pathways were not accentuated; (iv) the exercise-induced oxidative stress was enhanced with early changes in TBARS and RAA and enhanced maximal RAA consumption; and (v) the M-wave duration markedly increased during the recovery period.

CONCLUSIONS: The response of CFS patients to incremental exercise associates a lengthened and accentuated oxidative stress together with marked alterations of the muscle membrane excitability. These two objective signs of muscle dysfunction are sufficient to explain muscle pain and postexertional malaise reported by our patients.

 

Source: Jammes Y, Steinberg JG, Mambrini O, Brégeon F, Delliaux S. Chronic fatigue syndrome: assessment of increased oxidative stress and altered muscle excitability in response to incremental exercise. J Intern Med. 2005 Mar;257(3):299-310. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2796.2005.01452.x/full (Full article)

 

Chronic fatigue syndrome: lack of association between pain-related fear of movement and exercise capacity and disability

Abstract:

BACKGROUND AND PURPOSE: Patients who experience pain, a symptom of chronic fatigue syndrome (CFS), often exhibit kinesiophobia (irrational fear of movement). The purpose of this study was to examine whether pain-related fear of movement is associated with exercise capacity, activity limitations, or participation restrictions in patients with CFS who experience widespread pain.

SUBJECTS AND METHODS: Sixty-four subjects met the inclusion criteria. All subjects fulfilled the 1994 Centers for Disease Control and Prevention case definition for CFS and experienced widespread myalgias or arthralgias. The subjects completed the Tampa Scale for Kinesiophobia-Dutch Version (TSK-DV) and the Dutch Chronic Fatigue Syndrome-Activities and Participation Questionnaire (CFS-APQ). They then performed a maximal exercise test on a bicycle ergometer. Heart rate was monitored continuously by use of an electrocardiograph. Ventilatory factors were measured through spirometry. Correlations between the TSK-DV scores and both the exercise capacity data and the CFS-APQ scores were assessed using the Spearman rank correlation coefficient. Using the Mann-Whitney U test, the TSK-DV scores were compared between subjects who performed a maximal exercise stress test and those who did not perform the test.

RESULTS: Forty-seven subjects (73.4%) attained a total score of greater than 37 on the TSK-DV, indicating high fear of movement. Neither the exercise capacity data nor the CFS-APQ scores indicated a correlation with the TSK-DV scores (n=64). Subjects who did not perform a maximal exercise capacity test had more fear of movement (median TSK-DV score=43.0, interquartile range=10.3) compared with those who did perform a maximal exercise capacity test (median TSK-DV score=38.0, interquartile range=13.2; Mann-Whitney U-test score=322.5, z=-1.974, P=.048), but the correlation analysis was unable to reveal an association between exercise capacity and kinesiophobia in either subgroup.

DISCUSSION AND CONCLUSION: These results indicate a lack of correlation between kinesiophobia and exercise capacity, activity limitations, or participation restrictions, at least in patients with CFS who are experiencing widespread muscle or joint pain.

 

Source: Nijs J, Vanherberghen K, Duquet W, De Meirleir K. Chronic fatigue syndrome: lack of association between pain-related fear of movement and exercise capacity and disability. Phys Ther. 2004 Aug;84(8):696-705. http://ptjournal.apta.org/content/84/8/696.long (Full article)

 

Exercise lowers pain threshold in chronic fatigue syndrome

Abstract:

Post-exertional muscle pain is an important reason for disability in patients who are diagnosed to have Chronic Fatigue Syndrome (CFS). We compared changes in pain threshold in five CFS patients with five age and sex matched controls following graded exercise. Pain thresholds, measured in the skin web between thumb and index finger, increased in control subjects with exercise while it decreased in the CFS subjects. Increased perception of pain and/or fatigue after exercise may be indicative of a dysfunction of the central anti-nociceptive mechanism in CFS patients.

 

Source: Whiteside A, Hansen S, Chaudhuri A. Exercise lowers pain threshold in chronic fatigue syndrome. Pain. 2004 Jun;109(3):497-9. http://www.ncbi.nlm.nih.gov/pubmed/15157711

 

Chronic diffuse musculoskeletal pain, fibromyalgia and co-morbid unexplained clinical conditions

Abstract:

This chapter reviews our current knowledge on the presence of overlapping syndromes in one form of chronic diffuse pain, fibromyalgia. Patients with fibromyalgia often present with signs and symptoms of other unexplained clinical conditions, including chronic fatigue syndrome, irritable bowel syndrome, temporomandibular disorders, and multiple chemical sensitivities. The high prevalence, impact on function and opportunities for treatment underscore the need for clinicians and researchers to screen routinely for co-morbid unexplained clinical conditions among persons with fibromyalgia. We, therefore, describe a simple approach to screening for such conditions in accordance with published criteria. Interventions should directly address both fibromyalgia symptoms and co-morbid unexplained clinical conditions, as well as the multiple factors that propagate pain, fatigue and limitations in function.

 

Source: Aaron LA, Buchwald D. Chronic diffuse musculoskeletal pain, fibromyalgia and co-morbid unexplained clinical conditions. Best Pract Res Clin Rheumatol. 2003 Aug;17(4):563-74. http://www.ncbi.nlm.nih.gov/pubmed/12849712

 

Relationship between musculoskeletal symptoms and blood markers of oxidative stress in patients with chronic fatigue syndrome

Abstract:

In 21 patients with chronic fatigue syndrome (CFS) versus 20 normal subjects, we investigated the oxidant/antioxidant balance and its correlation with muscle symptoms. Patients versus controls showed significantly: lower Lag Phase and Vitamin E (Vit E) concentrations in plasma and low-density lipoproteins (LDL), higher LDL thiobarbituric acid reactive substances (TBARS), higher fatigue and lower muscle pain thresholds to electrical stimulation.

A significant direct linear correlation was found between fatigue and TBARS, thresholds and Lag Phase, thresholds and Vit E in plasma and LDL. A significant inverse linear correlation was found between fatigue and Lag Phase, fatigue and Vit E, thresholds and TBARS. Increased oxidative stress and decreased antioxidant defenses are related to the extent of symptomatology in CFS, suggesting that antioxidant supplementation might relieve muscle symptoms in the syndrome.

 

Source: Vecchiet J, Cipollone F, Falasca K, Mezzetti A, Pizzigallo E, Bucciarelli T, De Laurentis S, Affaitati G, De Cesare D, Giamberardino MA. Relationship between musculoskeletal symptoms and blood markers of oxidative stress in patients with chronic fatigue syndrome. Neurosci Lett. 2003 Jan 2;335(3):151-4. http://www.ncbi.nlm.nih.gov/pubmed/12531455