Role of fatigue in limiting physical activities in humans with neuromuscular diseases

Abstract:

New methods of examining both central and peripheral fatigue are now available. A broader understanding of the mechanisms of fatigue in healthy human subjects has begun to emerge. The mechanisms of fatigue in patients with various neuromuscular diseases are even more complex than in healthy persons. Examples of both central and peripheral fatigue in various neuromuscular diseases and other disorders are presented, including metabolic myopathy, chronic fatigue syndrome, postpolio syndrome, and amyotrophic lateral sclerosis.

 

Source: Miller RG. Role of fatigue in limiting physical activities in humans with neuromuscular diseases. Am J Phys Med Rehabil. 2002 Nov;81(11 Suppl):S99-107. http://www.ncbi.nlm.nih.gov/pubmed/12409815

 

Hemodynamic and neurohumoral responses to head-up tilt in patients with chronic fatigue syndrome

Abstract:

BACKGROUND: Data on the prevalence of orthostatic intolerance (OI) in patients with chronic fatigue syndrome (CFS) are limited and controversial. We tested the hypothesis that a majority of CFS patients exhibit OI during head-up tilt.

METHODS: Hemodynamic and neurohumoral responses to 40 minutes of head-up tilt were studied in 36 CFS patients and 36 healthy controls. Changes in stroke volume, cardiac output and peripheral vascular resistance were estimated from finger arterial pressure waveform analysis (Modelflow). Blood samples were drawn before and at the end of head-up tilt for measurement of plasma catecholamines.

RESULTS: At baseline, supine heart rate was higher in CFS patients (CFS: 66.4 +/- 8.4 bpm; controls: 57.4 +/- 6.6 bpm; p < 0.001) as was the plasma epinephrine level (CFS: 0.11 +/- 0.07 nmol/l; controls: 0.08 +/- 0.07 nmol/l: p = 0.015). An abnormal blood pressure and/or heart rate response to head-up tilt was seen in 10 (27.8 %) CFS patients (6 presyncope, 2 postural tachycardia, 2 tachycardia and presyncope) and 6 (16.7 %, p = 0.26) controls (5 presyncope, 1 tachycardia, 2 tachycardia and presyncope). Head-up tilt-negative CFS patients showed a larger decrease in stroke volume during tilt (-46.9 +/- 10.6) than head-up tilt-negative controls (-40.3 +/- 13.6 %, p = 0.008). Plasma catecholamine responses to head-up tilt did not differ between these groups.

CONCLUSION: Head-up tilt evokes postural tachycardia or (pre)syncope in a minority of CFS patients. The observations in head-up tilt-negative CFS patients of a higher heart rate at baseline together with a marked decrease in stroke volume in response to head-up tilt may point to deconditioning.

 

Source: Timmers HJ, Wieling W, Soetekouw PM, Bleijenberg G, Van Der Meer JW, Lenders JW. Hemodynamic and neurohumoral responses to head-up tilt in patients with chronic fatigue syndrome. Clin Auton Res. 2002 Aug;12(4):273-80. http://www.ncbi.nlm.nih.gov/pubmed/12357281

 

Latent class analysis of symptoms associated with chronic fatigue syndrome and fibromyalgia

Abstract:

BACKGROUND: Chronic fatigue syndrome and fibromyalgia continue to be perplexing conditions of unknown validity. Aetiological and symptomatic heterogeneity is likely and the distinctiveness of these disorders remains unclear. Our aims were to investigate empirically symptomatic heterogeneity in chronic fatigue syndrome and fibromyalgia.

METHODS: Latent class analysis was applied to data from 646 patients who met accepted criteria for chronic fatigue syndrome and/or fibromyalgia who were systematically evaluated at a specialist fatigue clinic. Thirty-two symptoms commonly found in chronic fatigue syndrome and fibromyalgia were entered into the latent class analysis.

RESULTS: We chose to interpret a four class solution. The classes appeared to differ in a graded fashion (rather than qualitatively) for symptom endorsements, pre-morbid characteristics, and co-morbidity with panic disorder and major depression.

CONCLUSIONS: These results were unexpected given the usual assumption of the distinctiveness of chronic fatigue syndrome and fibromyalgia. These results support a conceptualization of chronic fatigue syndrome and fibromyalgia as being characterized by greater similarities than differences.

 

Source: Sullivan PF, Smith W, Buchwald D. Latent class analysis of symptoms associated with chronic fatigue syndrome and fibromyalgia. Psychol Med. 2002 Jul;32(5):881-8. http://www.ncbi.nlm.nih.gov/pubmed/12171382

 

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

 

Fatigue after breast cancer and in chronic fatigue syndrome: similarities and differences

Abstract:

OBJECTIVE: Fatigue is investigated in 57 severely fatigued disease-free breast cancer patients and in 57 gender- and age-matched patients with chronic fatigue syndrome (CFS) using multidimensional and multimethod assessment. A comparison between these groups of patients is important to determine whether a cognitive behavioural intervention to reduce fatigue in CFS patients would be appropriate as well for severely fatigued disease-free breast cancer patients.

METHODS: Measurement included computerised questionnaires and a standardised neuropsychological test. Furthermore, patients filled out a daily Self-Observation List (SOL) and wore an actometer during a period of 12 days.

RESULTS: In comparison to severely fatigued disease-free breast cancer patients, CFS patients score more problematic with regard to the level of fatigue, functional impairment, physical activity, pain and self-efficacy. However, a subgroup of severely fatigued disease-free breast cancer patients reports the same amount of problems as CFS patients with regard to psychological well-being, sleep and concentration. Finally, CFS patients and severely fatigued breast cancer patients score equal on measures of social support.

CONCLUSION: There seem to be some similarities but also many differences between severely fatigued breast cancer survivors and females with CFS. Therefore, cognitive behaviour therapy (CBT) to reduce fatigue after treatment for cancer should also differ in certain aspects from cognitive behaviour therapy as it has been developed for patients with CFS.

 

Source: Servaes P, Prins J, Verhagen S, Bleijenberg G. Fatigue after breast cancer and in chronic fatigue syndrome: similarities and differences. J Psychosom Res. 2002 Jun;52(6):453-9. http://www.ncbi.nlm.nih.gov/pubmed/12069869

 

A factor analysis of chronic fatigue symptoms in a community-based sample

Abstract:

BACKGROUND: This study examined characteristics of fatigue in individuals with chronic fatigue from a community-based study. Most studies of chronic fatigue have been based on patients recruited from primary or tertiary care settings. Samples such as these might not be representative of patients within the general population. The purpose of this study was to determine the factor structure of participants’ symptoms in a random community sample of individuals with chronic fatigue.

METHOD: A random sample of 18,675 respondents in Chicago received a brief telephone questionnaire designed to identify individuals with chronic fatigue. A group of 780 (4.2%) with chronic fatigue received further interview via telephone questionnaire involving characteristics of their fatigue. The analyses for this study were based on those people identified with having chronic fatigue. A factor analysis was conducted on responses to questionnaire items, and a four-factor solution emerged. Mean factor scores were derived and analyzed in relation to sociodemographic characteristics and sample subgroups.

RESULTS: The four factors were labeled: Lack of Energy, Physical Exertion, Cognitive Functioning, and Fatigue and Rest.

CONCLUSIONS: Results indicated that individuals with chronic fatigue have symptoms that can be differentiated into theoretically distinct factors.

 

Source: Jason LA, Taylor RR, Kennedy CL, Jordan K, Huang CF, Torres-Harding S, Song S, Johnson D. A factor analysis of chronic fatigue symptoms in a community-based sample.  Soc Psychiatry Psychiatr Epidemiol. 2002 Apr;37(4):183-9. http://www.ncbi.nlm.nih.gov/pubmed/12027245

 

Peripheral vestibular dysfunction in chronic fatigue syndrome

Abstract:

OBJECTIVE: To report left-sided peripheral vestibular failure as the cause of dizziness in a 12-year-old boy diagnosed as having chronic fatigue syndrome (CFS).

DESIGN: Retrospective case report with review of literature and discussion.

SETTING: Tertiary children’s hospital.

CONCLUSION: We recommend proper vestibular assessment for CFS patients presenting with dizziness, as effective treatment for peripheral vestibular disorder exists in the form of balance rehabilitation exercises.

 

Source: Palaniappan R, Sirimanna T. Peripheral vestibular dysfunction in chronic fatigue syndrome. Int J Pediatr Otorhinolaryngol. 2002 May 31;64(1):69-72. http://www.ncbi.nlm.nih.gov/pubmed/12020917

 

Impaired postural cerebral hemodynamics in young patients with chronic fatigue with and without orthostatic intolerance

Abstract:

OBJECTIVES: To measure postural changes in cerebral hemodynamics in young patients with chronic fatigue with and without orthostatic intolerance.

STUDY DESIGN: We studied 28 patients (age, 10 to 22 years) and 20 healthy control subjects (age, 6 to 27 years). Cerebral oxygenated hemoglobin (oxy-Hb) and deoxygenated Hb were noninvasively and continuously measured with near infrared spectroscopy during active standing. Beat-to-beat arterial pressure was monitored by Finapres.

RESULTS: Orthostatic intolerance determined by cardiovascular responses to standing was observed in 16 of 28 patients: instantaneous orthostatic hypotension in 8, delayed orthostatic hypotension in 2, and postural orthostatic tachycardia in 6. A rapid recovery of oxy-Hb by near infrared spectroscopy at the onset of active standing was not found in 15 of 16 patients with chronic fatigue and orthostatic intolerance and in 6 of 12 patients with chronic fatigue without orthostatic intolerance but only in 2 of 20 control subjects. Thirteen of 16 patients with orthostatic intolerance showed prolonged reduction in oxy-Hb during standing.

CONCLUSIONS: Impaired cerebral hemodynamics in patients with chronic fatigue syndrome and postural orthostatic tachycardia suggest a link between impaired cerebral oxygenation and chronic fatigue. However, this cannot explain the symptoms in patients meeting the criteria of chronic fatigue without orthostatic intolerance.

Comment in:

Chronic fatigue syndrome and Addison’s disease. [J Pediatr. 2003]

Orthostatic intolerance and chronic fatigue syndrome: new light on an old problem. [J Pediatr. 2002]

 

Source: Tanaka H, Matsushima R, Tamai H, Kajimoto Y. Impaired postural cerebral hemodynamics in young patients with chronic fatigue with and without orthostatic intolerance. J Pediatr. 2002 Apr;140(4):412-7. http://www.ncbi.nlm.nih.gov/pubmed/12006954

 

Mediators of inflammation and their interaction with sleep: relevance for chronic fatigue syndrome and related conditions

Abstract:

In humans, activation of the primary host defense system leads to increased or decreased NREM sleep quality, depending on the degree of early immune activation. Modest elevations of certain inflammatory cytokines are found during experimental sleep loss in humans and, in addition, relatively small elevations of cytokines are seen following commencement of pharmacological treatments with clozapine, a CNS active antipsychotic agent, known to have immunomodulatory properties. Cytokines such as TNF-alpha, its soluble receptors, and IL-6, present in the periphery and the CNS, comprise a link between peripheral immune stimulation and CNS-mediated behaviors and experiences such as sleep, sleepiness, and fatigue. The debilitating fatigue experienced in chronic fatigue syndrome and related diseases may also be related to altered cytokine profiles.

 

Source: Mullington JM, Hinze-Selch D, Pollmächer T. Mediators of inflammation and their interaction with sleep: relevance for chronic fatigue syndrome and related conditions.  Ann N Y Acad Sci. 2001 Mar;933:201-10. http://www.ncbi.nlm.nih.gov/pubmed/12000021

 

Dry eyes and mouth syndrome–a subgroup of patients presenting with sicca symptoms

Abstract:

OBJECTIVE: To evaluate the characteristics of patients presenting with symptoms suggestive of Sjögren’s syndrome (SS) but failing to satisfy diagnostic criteria.

METHODS: Clinical, serological and histological data were collected on 34 patients presenting with dry eyes and/or mouth who did not satisfy the Vitali criteria for the diagnosis of SS. They were compared with 136 patients with primary SS, 38 patients with secondary SS, and 13 patients without SS. Questionnaires on symptoms from each group were compared with 43 healthy controls.

RESULTS: The 34 patients who did not satisfy the diagnostic criteria for SS or any other connective tissue disease were designated dry eyes and mouth syndrome (DEMS). Their demography including age was similar to that of a primary SS group and there was no more atrophy seen on their biopsies compared with SS and non-SS controls. They scored highly on visual analogue scales of symptoms but had few objective signs. All were negative for anti-Ro and anti-La although the prevalence of antinuclear antibodies (19%) was increased compared with a normal population. There was no excess of SS-associated tissue types.

CONCLUSION: There was no evidence that age, salivary gland atrophy or subclinical SS accounted for the symptoms in DEMS. Most of the patients fitted into a spectrum of disease which tended more towards fibromyalgia and/or chronic fatigue syndrome.

Comment in: Dry eyes and mouth syndrome or sicca, asthenia and polyalgia syndrome? [Rheumatology (Oxford). 2003]

 

Source: Price EJ, Venables PJ. Dry eyes and mouth syndrome–a subgroup of patients presenting with sicca symptoms. Rheumatology (Oxford). 2002 Apr;41(4):416-22. http://rheumatology.oxfordjournals.org/content/41/4/416.long (Full article)