Research Provides More Evidence That Chronic Fatigue Syndrome Is A Legitimate Medical Condition

Press Release: Researchers at Georgetown University Medical Center have found that chronic fatigue syndrome (CFS) may be rooted in distinct neurological abnormalities that can be medically tested. Although the sample studied was small, this research provides objective, physiological evidence that the controversial disorder can be considered a legitimate medical condition.

Chronic fatigue syndrome defines a range of illnesses including fibromyalgia and Gulf War syndrome, all of which have fatigue as a major symptom. Even among medical professionals, there is a disagreement about the causes, diagnosis and treatment of CFS because so much about the disorder remains unknown. One reason CFS is difficult to diagnose is because it shares symptoms with many other diseases, including multiple sclerosis and lupus. Even when other illnesses are ruled out and a CFS diagnosis is given, there is not a standardized course of treatment and it’s difficult for doctors to measure patient improvement. Estimates are that two to four times as many women as men are diagnosed with CFS.

The Georgetown study, published in the November edition of the BMC Neurology Journal, an online publication, reveals that patients diagnosed with CFS and its family of illnesses have a set of proteins in their spinal cord fluid that were not detected in healthy individuals. These proteins might give insight into the causes of CFS and could someday be used as markers to diagnose patients with the disorder.

“For years, patients with chronic fatigue syndrome have suffered from painful symptoms for which there is no blood test, diagnosable physical condition or any method for doctors to measure improvement,” said James Baraniuk, MD, assistant professor of medicine at Georgetown University Medical Center and first author on the study. “Our research provides initial evidence that chronic fatigue syndrome and its family of illnesses may be legitimate, neurological diseases and that at least part of the pathology involves the central nervous system.”

The disorder is characterized by profound fatigue that is not improved by bed rest and that may get worse with physical or mental activity, according to the Centers for Disease Control and Prevention. Persons with CFS usually function at a lower level of activity than they were capable of before the onset of illness, feeling too tired to perform normal activities or easily exhausted with no apparent reason. Patients also report various nonspecific symptoms, including weakness, muscle pain, impaired memory and/or mental concentration, insomnia and post-exertional fatigue lasting more than 24 hours.

The study looked at 50 individuals suffering from at least two disorders related to CFS, including fibromyalgia and Gulf War syndrome. By examining spinal cord fluid in patients with CFS and in healthy individuals, the researchers found that CFS patients have 16 proteins that healthy individuals do not. Five of these 16 proteins are found in all patients with the illnesses but in none of the controls. The results indicate that those 16 proteins could possibly serve as a “biosignature” for the disease and could someday be used to diagnose CFS.

“Although this is a small study and more research on the subject is necessary, these results indicate it might be possible to develop a simple laboratory test to diagnose these disorders in the future,” Baraniuk said.

Other co-authors on the paper include Begona Casada, PhD, and Hilda Maibach, MS, of Georgetown University Medical Center; Daniel J. Clauw, MD, of the University of Michigan; and Lewis K. Pannell, PhD, of the University of South Carolina; and Sonya Hess, PhD, of the National Institute of Diabetes and Digestive and Kidney Diseases.

 

Source: Georgetown University Medical Center. “Research Provides More Evidence That Chronic Fatigue Syndrome Is A Legitimate Medical Condition.” ScienceDaily. ScienceDaily, 10 January 2006. www.sciencedaily.com/releases/2006/01/060110013424.htm

Functional somatic syndromes: sensitivities and specificities of self-reports of physician diagnosis

Abstract:

OBJECTIVE: Functional somatic syndromes have no laboratory or pathologic abnormalities and so are diagnosed by symptom-based case definitions. However, many studies, including recent ones, have used self-reports of physician diagnosis rather than the case definitions. Our objective was to determine the sensitivities and specificities of self-report of physician diagnosis for chronic fatigue syndrome (CFS), fibromyalgia (FM), irritable bowel syndrome (IBS), panic disorder, and migraine.

METHODS: Each of 312 female patients with incident interstitial cystitis/bladder pain syndrome and matched population-based controls were queried on self-report of physician diagnosis and separately on established case definitions for each of these syndromes.

RESULTS: Using the symptom-based case definitions as standards, we found that self-report of physician diagnosis did not identify 90% of the controls who had CFS, 77% who had FM, 69% who had IBS, 43% who had panic disorder, and 23% who had migraine. In addition, it missed most individuals with multiple syndromes. Findings in one cohort (controls) were confirmed in another (patients with interstitial cystitis/bladder pain syndrome).

CONCLUSIONS: Self-report of physician diagnosis did not identify most of the three most venerable functional somatic syndromes, IBS, FM, and, especially, CFS; nor did it identify substantial minorities of individuals with panic disorder and migraine. Self-report of physician diagnosis was particularly poor in recognizing persons with multiple syndromes. The insensitivity of this diagnostic test has effects on not only prevalence and incidence estimates but also correlates, comorbidities, and case recruitment. To reveal individuals with these syndromes, singly or together, queries of symptoms, not diagnoses, are necessary.

Comment in: Recalling, reporting, and thinking about diagnoses. [Psychosom Med. 2012]

 

Source: Warren JW, Clauw DJ. Functional somatic syndromes: sensitivities and specificities of self-reports of physician diagnosis. Psychosom Med. 2012 Nov-Dec;74(9):891-5. doi: 10.1097/PSY.0b013e31827264aa. Epub 2012 Oct 15. https://www.ncbi.nlm.nih.gov/pubmed/23071343

 

Prognostic factors for recent-onset interstitial cystitis/painful bladder syndrome

Abstract:

Study Type – Prognosis (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? Interstitial cystitis/painful bladder syndrome (IC/PBS) comprises pain perceived to be from the bladder, urinary urgency and frequency, and nocturia. As diagnosed at present, it is primarily identified in adult women. It is a chronic disease yet its natural history has not been well studied. In a prospective study of 304 incident female IC/PBS cases followed for a median of 33 months after onset, women with baseline chronic fatigue syndrome had a worse prognosis for IC/PBS. Mild IC/PBS at baseline was the only variable that was directly associated with a good prognosis.

OBJECTIVE: To identify baseline variables that predict the prognosis of interstitial cystitis/painful bladder syndrome (IC/PBS) in women seeking medical care for recent onset of this syndrome.

SUBJECTS AND METHODS: In a prospective study of women with incident IC/PBS (≤12 months of symptoms), we contacted patients at intervals and asked standardized questions about IC/PBS symptoms in the previous week. Logistic regression analyses assessed baseline variables as predictors of mild vs more severe IC/PBS at the last follow-up.

RESULTS: Median length of follow-up was 33 months after onset of IC/PBS; 304 (97%) patients had at least one follow-up assessment. Mild IC/PBS at baseline was the only variable that was directly associated with a mild IC/PBS endpoint. Conversely, a history of chronic fatigue syndrome (CFS) was inversely associated with a mild endpoint of IC/PBS (i.e. individuals with CFS had a worse prognosis for their IC/PBS symptoms).

CONCLUSIONS: At a median of nearly 3 years after onset, baseline mild IC/PBS was directly associated with a milder disease severity. Baseline co-morbid CFS was associated with more severe disease. Whether CFS was uniquely associated or represented several co-morbid non-bladder syndromes (NBSs) could not be determined.

© 2012 BJU INTERNATIONAL.

Comment in: Re: prognostic factors for recent-onset interstitial cystitis/painful bladder syndrome. [J Urol. 2013]

 

Source: Warren JW, Clauw DJ, Langenberg P. Prognostic factors for recent-onset interstitial cystitis/painful bladder syndrome. BJU Int. 2013 Mar;111(3 Pt B):E92-7. doi: 10.1111/j.1464-410X.2012.11422.x. Epub 2012 Aug 9. http://onlinelibrary.wiley.com/doi/10.1111/j.1464-410X.2012.11422.x/full (Full article)

Perspectives on fatigue from the study of chronic fatigue syndrome and related conditions

Abstract:

Fatigue is a symptom whose causes are protean and whose phenotype includes physical, mood, and behavioral components. Chronic fatigue syndrome (CFS) is an illness that has strong biological underpinnings and no definite etiology. Diagnostic criteria established by the Centers for Disease Control and Prevention have helped classify CFS as an overlap of mood, behavioral, and biological components. These include the presence of fatigue for more than 6 months associated with a diminution of functional activity and somatic symptoms, and pain not attributable to a specific diagnosis or disease. Four of the following criteria need to be present: sore throat, impaired memory or cognition, unrefreshing sleep, postexertional fatigue, tender glands, aching stiff muscles, joint pain, and headaches.

Many researchers have observed that CFS shares features in common with other somatic syndromes, including irritable bowel syndrome, fibromyalgia, and temporomandibular joint dysfunction. Correlations between inflammation and infection, augmented sensory processing, abnormalities of neurotransmitters, nerve growth factors, low levels of serotonin and norepinephrine, abnormalities of homeostasis of the stress system, and autonomic dysfunction may be hallmarks of CFS. The relative contributions of each of these abnormalities to the profound fatigue associated with CFS need to be explored further to better evaluate and treat the syndrome.

Copyright (c) 2010 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

 

Source: Clauw DJ. Perspectives on fatigue from the study of chronic fatigue syndrome and related conditions. PM R. 2010 May;2(5):414-30. doi: 10.1016/j.pmrj.2010.04.010. https://www.ncbi.nlm.nih.gov/pubmed/20656623

 

Comorbid somatic symptoms and functional status in patients with fibromyalgia and chronic fatigue syndrome: sensory amplification as a common mechanism

Abstract:

BACKGROUND: Somatic symptoms are common in conditions such as fibromyalgia (FM) and chronic fatigue syndrome (CFS).

OBJECTIVE: Authors investigated a potential shared pathologic mechanism: a generalized perceptual abnormality where there is heightened responsiveness to varied sensory stimulation, including pain.

METHOD: A composite measure of sensory sensitivity was created and compared with measures of somatic symptoms, comorbid psychological disturbances, and self-reported physical functioning in 38 patients with FM and/or CFS.

RESULTS: Sensory amplification influenced physical functioning indirectly through pain intensity, and physical symptoms and fatigue also independently contributed to physical functioning.

CONCLUSION: Sensory amplification may be an underlying pathophysiologic mechanism in these disorders that is relatively independent of depression and depressive symptoms.

 

Source: Geisser ME, Strader Donnell C, Petzke F, Gracely RH, Clauw DJ, Williams DA. Comorbid somatic symptoms and functional status in patients with fibromyalgia and chronic fatigue syndrome: sensory amplification as a common mechanism. Psychosomatics. 2008 May-Jun;49(3):235-42. doi: 10.1176/appi.psy.49.3.235. https://www.ncbi.nlm.nih.gov/pubmed/18448779

 

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

 

Ambulatory monitoring of physical activity and symptoms in fibromyalgia and chronic fatigue syndrome

Abstract:

OBJECTIVE: Fibromyalgia (FM) and chronic fatigue syndrome (CFS) are associated with substantial physical disability. Determinants of self-reported physical disability are poorly understood. This investigation uses objective ambulatory activity monitoring to compare patients with FM and/or CFS with controls, and examines associations of ambulatory activity levels with both physical function and symptoms during activities of daily life.

METHODS: Patients with FM and/or CFS (n = 38, mean +/- SD age 41.5 +/- 8.2 years, 74% women) completed a 5-day program of ambulatory monitoring of physical activity and symptoms (pain, fatigue, and distress) and results were compared with those in age-matched controls (n = 27, mean +/- SD age 38.0 +/- 8.6 years, 44% women). Activity levels were assessed continuously, ambulatory symptoms were determined using electronically time-stamped recordings at 5 time points during each day, and physical function was measured with the 36-item Short Form health survey at the end of the 5-day monitoring period.

RESULTS: Patients had significantly lower peak activity levels than controls (mean +/- SEM 8,654 +/- 527 versus 12,913 +/- 1,462 units; P = 0.003) and spent less time in high-level activities when compared with controls (P = 0.001). In contrast, patients had similar average activity levels as those of controls (mean +/- SEM 1,525 +/- 63 versus 1,602 +/- 89; P = 0.47). Among patients, low activity levels were associated with worse self-reported physical function over the preceding month. Activity levels were inversely related to concurrent ambulatory pain (P = 0.031) and fatigue (P < 0.001). Pain and fatigue were associated with reduced subsequent ambulatory activity levels, whereas activity levels were not predictive of subsequent symptoms.

CONCLUSION: Patients with FM and/or CFS engaged in less high-intensity physical activities than that recorded for sedentary control subjects. This reduced peak activity was correlated with measures of poor physical function. The observed associations may be relevant to the design of behavioral activation programs, because activity levels appear to be contingent on, rather than predictive of, symptoms.

 

Source: Kop WJ, Lyden A, Berlin AA, Ambrose K, Olsen C, Gracely RH, Williams DA, Clauw DJ. Ambulatory monitoring of physical activity and symptoms in fibromyalgia and chronic fatigue syndrome. Arthritis Rheum. 2005 Jan;52(1):296-303. http://onlinelibrary.wiley.com/doi/10.1002/art.20779/full (Full article)

 

A tender sinus does not always mean rhinosinusitis

Abstract:

BACKGROUND: Sinus tenderness has not been quantitatively assessed.

OBJECTIVE: We sought to compare sinus and systemic tenderness in rhinosinusitis, allergic rhinitis, and chronic fatigue syndrome (CFS), and healthy (non-CFS) groups.

METHODS: Cutaneous pressures (kg/cm(2)) causing pain at 5 sinus and 18 systemic sites were measured in acute and chronic rhinosinusitis, active allergic rhinitis, healthy non-CFS/no rhinosinusitis, and CFS subjects.

RESULTS: Sinus thresholds differed significantly (P </= 10(-11), ANOVA) between non-CFS/no rhinosinusitis (1.59 +/- 0.14 kg/cm(2), mean +/- 95% CI, n = 117), allergic rhinitis (1.19 +/- 0.31, n = 30), exacerbations of chronic rhinosinusitis (1.25 +/- 0.26, n = 25), non-CFS/chronic rhinosinusitis (1.23 +/- 0.27, n = 23), acute rhinosinusitis (1.10 +/- 0.20, n = 22), CFS/no rhinosinusitis (0.98 +/- 0.15, n = 70), and CFS/chronic rhinosinusitis (0.78 +/- 0.12, n = 56). Systemic pressure thresholds were lower for CFS (1.46 +/- 0.15) than for non-CFS (2.67 +/- 0.22, P </= 10(-11)).

CONCLUSIONS: The lower sinus thresholds of rhinosinusitis groups validated the sign of sinus tenderness. Sinus and systemic thresholds were both 44% lower in CFS than in non-CFS subjects, suggesting that systemic hyperalgesia contributed to CFS sinus tenderness and “rhinosinusitis” complaints.

 

Source: Naranch K, Park YJ, Repka-Ramirez MS, Velarde A, Clauw D, Baraniuk JN. A tender sinus does not always mean rhinosinusitis. Otolaryngol Head Neck Surg. 2002 Nov;127(5):387-97. http://www.ncbi.nlm.nih.gov/pubmed/12447232

 

Cytokines in nasal lavage fluids from acute sinusitis, allergic rhinitis, and chronic fatigue syndrome subjects

Abstract:

The aim of this study was to compare the degree of inflammation present in acute sinusitis, allergic rhinitis, chronic Fatigue Syndrome (CFS), and non-CFS control subjects by measuring cytokine concentrations in nasal lavage fluids. The concentrations of total protein (TP; Lowry assay), nerve growth factor (NGF), tumor necrosis factor (TNF) alpha, and interleukin (IL)-8 were measured by ELISA in nasal lavage fluids from acute sinusitis (n = 13), active allergic rhinitis (n = 16), CFS (n = 95), and non-CFS (n = 89) subjects. CFS and non-CFS groups were subdivided further using allergy skin test and rhinitis score results. Acute sinusitis subjects had significantly higher TP (p = 0.011, ANOVA), TNF-alpha (p = 0.00071), and IL-8 (p = 0.0000027) concentrations and IL-8/TP ratios (p = 0.0030) than the other three patient groups. There were no differences based on skin test or rhinitis score severity within either the CFS or non-CFS groups. The mucopurulent discharge of acute sinusitis contained significantly higher TNF-alpha and IL-8. Neutrophils were a likely source for these cytokines. There were no differences between CFS and non-CFS subjects, making it unlikely that the rhinitis of CFS has an inflammatory component.

 

Source: Repka-Ramirez S, Naranch K, Park YJ, Clauw D, Baraniuk JN. Cytokines in nasal lavage fluids from acute sinusitis, allergic rhinitis, and chronic fatigue syndrome subjects. Allergy Asthma Proc. 2002 May-Jun;23(3):185-90. http://www.ncbi.nlm.nih.gov/pubmed/12125506

 

IgE levels are the same in chronic fatigue syndrome (CFS) and control subjects when stratified by allergy skin test results and rhinitis types

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) has an uncertain pathogenesis. Allergies have been suggested as one cause.

OBJECTIVE: The aim of this study was to compare serum immunoglobulin (Ig)E in CFS and control subjects to determine whether IgE levels were elevated in CFS. This would be suggestive of increased atopy in CFS.

METHODS: IgE was measured by quantitative ELISA (sandwich) immunoassay in 95 CFS and 109 non-CFS control subjects. Subjects were classified by positive or negative allergy skin tests (AST) and rhinitis questionnaires (rhinitis score, RhSc) into four rhinitis types: nonallergic rhinitis (NAR with positive RhSc and negative AST); allergic rhinitis (AR with positive AST and RhSc); atopic/no rhinitis (AST positive/RhSc negative); and nonatopic/no rhinitis (both AST and RhSc negative) subjects.

RESULTS: IgE was not significantly different between control (128 +/- 18 IU/mL, mean +/- SEM) and CFS (133 +/- 43 IU/mL) groups, or between control and CFS groups classified into the four rhinitis types. IgE was significantly higher in subjects with positive AST whether or not they had positive RhSc or CFS symptoms.

CONCLUSIONS: Elevated IgE and positive AST indicate allergen sensitization, but are not necessarily indicators of symptomatic allergic diseases. There was no association between IgE levels and CFS, indicating that atopy was probably not more prevalent in CFS. Therefore, TH2-lymphocyte and IgE-mast cell mechanisms are unlikely causes of CFS.

 

Source: Repka-Ramirez MS, Naranch K, Park YJ, Velarde A, Clauw D, Baraniuk JN. IgE levels are the same in chronic fatigue syndrome (CFS) and control subjects when stratified by allergy skin test results and rhinitis types. Ann Allergy Asthma Immunol. 2001 Sep;87(3):218-21. http://www.ncbi.nlm.nih.gov/pubmed/11570618