Functional status in patients with chronic fatigue syndrome, other fatiguing illnesses, and healthy individuals

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is a condition that may be associated with substantial disability. The Medical Outcomes Study Short-Form General Health Survey (SF-36) is an instrument that has been widely used in outpatient populations to determine functional status. Our objectives were to describe the usefulness of the SF-36 in CFS patients and to determine if subscale scores could distinguish patients with CFS from subjects with unexplained chronic fatigue (CF), major depression (MD), or acute infectious mononucleosis (AIM), and from healthy control subjects (HC). An additional goal was to ascertain if subscale scores correlated with the signs and symptoms of CFS or the presence of psychiatric disorders and fibromyalgia.

DESIGN: Prospectively collected case series.

SETTING: Patients with CFS and CF were seen in a university-based referral clinic and had undergone a complete medical and psychiatric evaluation. Other study subjects were recruited from the community to participate in research studies.

PARTICIPANTS: The study included 185 patients with CFS, 246 with CF, 111 with AIM, and 25 with MD. There were 99 HC subjects.

MEASURES: The SF-36 and a structured psychiatric interview were used. The SF-36 contains 8 subscales: physical, emotional, social, and role functioning, body pain, mental health, vitality, and general health- and a structured psychiatric interview.

RESULTS: Performance characteristics (internal reliability coefficients, convergent validity) of the SF-36 were excellent. A strikingly consistent pattern was found for the physical functioning, role functioning, social functioning, general health, and body pain subscales, with the lowest scores in CFS patients, intermediate scores in AIM patients, and the highest scores in the HC subjects. The CFS patients had significantly lower scores than patients with CF alone on the physical functioning (P < or = 0.01), role functioning (P < or = 0.01), and body pain (P < or = 0.001) subscales. The emotional functioning and mental health scores were worst among those with MD. The presence of fibromyalgia, being unemployed, and increasing fatigue severity all were associated with additional functional limitations across multiple functional domains, with increasing fatigue appearing to have the greatest effect.

CONCLUSIONS: The SF-36 is useful in assessing functional status in patients with fatiguing illnesses. Patients with CFS and CF have marked impairment of their functional status. The severity and pattern of impairment as documented by the SF-36 distinguishes patients with CFS and CF from those with MD and AIM, and from HC, but does not discriminate between CF and CFS.

 

Source: Buchwald D, Pearlman T, Umali J, Schmaling K, Katon W. Functional status in patients with chronic fatigue syndrome, other fatiguing illnesses, and healthy individuals. Am J Med. 1996 Oct;101(4):364-70. http://www.ncbi.nlm.nih.gov/pubmed/8873506

 

Chronic fatigue, chronic fatigue syndrome, and fibromyalgia. Disability and health-care use

Abstract:

OBJECTIVES: Disabling chronic fatigue that does not meet criteria for chronic fatigue syndrome (CFS) or fibromyalgia (FM) is a condition thought to be associated with substantial disability and an apparently high use of health-care services. The authors compare patients who have chronic fatigue, CFS, FM, or CFS and FM together (CFS+FM) on employment status, self-reported disability, number of medical care visits, type of services obtained, and other diagnoses received.

METHODS: The authors studied 402 patients from a university-based chronic fatigue clinic. All patients underwent an initial structured diagnostic assessment. One hundred forty-seven patients met case criteria for CFS, 28 for FM, 61 for CFS+FM, and 166 fell in the residual chronic fatigue group. Of these patients, 388 completed a follow-up questionnaire an average of 1.7 years later. Chi-squared tests and analysis of variance were used to compare groups on follow-up measures of health-care use and disability.

RESULTS: Patients with chronic fatigue, CFS, FM, and CFS+FM were similar in terms of disability and health-care use, though those with CFS+FM were significantly more likely to be unemployed and to use more chiropractic and “other” provider services. Rates of unemployment ranged from 26% (chronic fatigue) to 51% (CFS+FM). Overall, patients reported a mean of 21 visits to a wide variety health-care providers during the previous year, with no significant differences between groups.

CONCLUSIONS: Chronic fatigue, CFS, and FM are associated with considerable personal and occupational disability and low rates of employment. The potentially large economic burden of these disorders underscores the need for accurate estimates of direct and indirect costs, the relative contribution of individual factors to disability, and the need to develop targeted rehabilitation programs.

 

Source: Bombardier CH, Buchwald D. Chronic fatigue, chronic fatigue syndrome, and fibromyalgia. Disability and health-care use. Med Care. 1996 Sep;34(9):924-30. http://www.ncbi.nlm.nih.gov/pubmed/8792781

 

Evidence that abnormalities of central neurohormonal systems are key to understanding fibromyalgia and chronic fatigue syndrome

Abstract:

Fibromyalgia (FM) and chronic fatigue syndrome (CFS) fall into the spectrum of what might be termed stress-associated syndromes by virtue of frequent onset after acute or chronic stressors and apparent exacerbation of symptoms during periods of physical or emotional stress. These illnesses also share perturbation of the hypothalamic-pituitary-adrenal axis and sympathetic stress response systems. In this article, the authors discuss the specific neurohormonal abnormalities found in FM and CFS and potential mechanisms by which dysfunction of neurohormonal stress-response systems could contribute to vulnerability to stress-associated syndromes and to the symptoms of FM and CFS.

 

Source: Crofford LJ, Demitrack MA. Evidence that abnormalities of central neurohormonal systems are key to understanding fibromyalgia and chronic fatigue syndrome. Rheum Dis Clin North Am. 1996 May;22(2):267-84. http://www.ncbi.nlm.nih.gov/pubmed/8860799

 

Periodic K-alpha sleep EEG activity and periodic limb movements during sleep: comparisons of clinical features and sleep parameters

Abstract:

The K-alpha sleep electroencephalographic (EEG) phenomenon is characterized by periodic (approximately 20-40 seconds) K-complexes, immediately followed by alpha-EEG activity (7.5-11 Hz) of 0.5- to 5.0-second duration. A group of 14 subjects with the periodic K-alpha anomaly was found to have a similar distribution pattern of interevent intervals as compared with previously published data for sleep-related periodic limb movements during sleep (PLMS). Sleep parameters and somatic symptoms of 30 patients with K-alpha were compared with 30 patients with PLMS. The periodic K-alpha group was predominantly female, younger, exhibiting more slow-wave sleep, gastrointestinal symptoms and muscular complaints and fewer movement arousals on overnight polysomnography. The K-alpha group presented uniformly with complaints of unrefreshing sleep, often associated with fibromyalgia and chronic fatigue syndrome. The PLMS group was predominantly male, showed greater sleep disruption and presented with a variety of sleep-related symptoms.

 

Source: MacFarlane JG, Shahal B, Mously C, Moldofsky H. Periodic K-alpha sleep EEG activity and periodic limb movements during sleep: comparisons of clinical features and sleep parameters. Sleep. 1996 Apr;19(3):200-4. http://www.ncbi.nlm.nih.gov/pubmed/8723376

 

Silicone breast implant–associated musculoskeletal manifestations

Abstract:

Three hundred consecutive women with silicone breast implants (SBI), referred to the arthritis clinic with a variety of musculoskeletal complaints, were evaluated for the presence of underlying connective tissue disease. A complete history and physical examination were performed, as well as laboratory testing for C-reactive protein, rheumatoid factor; and autoantibody determination by indirect immunofluorescence and immunodiffusion.

The group mean age was 44.4 years (range 25-69), the mean time from initial implant surgery to appearance of symptoms was 6.8 years (range: 6m-19y) and 83.3% of women studied had clinical manifestations highly suggestive of an underlying connective tissue disorder. Fifty-four percent met criteria for fibromyalgia and/or chronic fatigue syndrome, distinct connective tissue diseases was detected in 11%, undifferentiated connective tissue disease or human adjuvant disease was found in 10.6%, and a variety of disorders such as angioneurotic oedema, frozen shoulder, multiple sclerosis-like syndrome were present.

Several other miscellaneous conditions including recurrent unexplained low grade fever, hair loss, skin rash, sicca symptoms, Raynaud’s phenomenon, carpal tunnel syndrome, memory loss, headaches, chest pain, and shortness of breath were also seen accompanying specific and non-specific conditions. Seventy percent of patients who underwent explanation of the implants reported improvement of their systemic symptomatology.

A significant proportion of SBI patients referred for rheumatic evaluation have clinical manifestations highly suggestive of an underlying connective tissue disease. Furthermore, improvement of their symptomatology follows explanation of the implants in over half of the patients.

 

Source: Cuellar ML, Gluck O, Molina JF, Gutierrez S, Garcia C, Espinoza R. Silicone breast implant–associated musculoskeletal manifestations. Clin Rheumatol. 1995 Nov;14(6):667-72. http://www.ncbi.nlm.nih.gov/pubmed/8608686

 

The pathogenesis of chronic pain and fatigue syndromes, with special reference to fibromyalgia

Abstract:

Syndromes characterized by chronic pain and fatigue have been described in the medical literature for centuries. Fibromyalgia is the term currently used to describe this symptom complex, and considerable research has been performed in the last decade to delineate the epidemiology, pathophysiology, and genesis of this entity. Although fibromyalgia is defined by its musculoskeletal features, it is clear that there are a large number of non-musculoskeletal symptoms, such that we now understand that there is considerable overlap with allied conditions such as the chronic fatigue syndrome, migraine and tension headaches, irritable bowel syndrome, and affective disorders. This article will review our current state of knowledge regarding fibromyalgia and these allied conditions, and present a unifying hypothesis that describes both the pathophysiology of symptoms and the genesis of these disorders.

 

Source: Clauw DJ. The pathogenesis of chronic pain and fatigue syndromes, with special reference to fibromyalgia. Med Hypotheses. 1995 May;44(5):369-78. http://www.ncbi.nlm.nih.gov/pubmed/8583967

 

Absence of parvovirus B19 infection in chronic fatigue syndrome

Abstract:

OBJECTIVE: To evaluate the presence of infection with parvovirus B19 in patients with chronic fatigue syndrome (CFS) who also had rheumatologic symptoms and mild hematologic abnormalities.

METHODS: Seven patients meeting the Centers for Disease Control and Prevention working case definition for CFS who also had mild leukopenia, thrombocytopenia, or anemia were studied. Bone marrow was aspirated from each patient, and examined for morphologic abnormalities, including features seen in marrow infections with parvovirus B19, as well as for parvoviral DNA, using polymerase chain reaction (PCR) amplification. Serum obtained at the time of marrow aspiration was also evaluated for parvoviral DNA, using the PCR method, and was examined for the presence of IgM and IgG antibodies to the virus.

RESULTS: No evidence of marrow involvement with parvovirus B19 was found in any patient. One patient had antibody evidence of a transient parvoviral infection, during which time an underlying thrombocytopenia worsened.

CONCLUSION: Despite examining a selected group of patients thought most likely to have parvoviral infection, based on clinical and hematologic measures, no evidence of clinically important parvoviral infection was noted. Thus, it seems unlikely that parvovirus B19 plays a role in CFS, even though it has been associated with fibromyalgia, a clinically similar syndrome.

 

Source: Ilaria RL Jr, Komaroff AL, Fagioli LR, Moloney WC, True CA, Naides SJ. Absence of parvovirus B19 infection in chronic fatigue syndrome. Arthritis Rheum. 1995 May;38(5):638-41. http://www.ncbi.nlm.nih.gov/pubmed/7748220

 

Fibromyalgia, chronic fatigue syndrome, and myofascial pain syndrome

Abstract:

Two important studies in which nuclear magnetic resonance spectroscopy was used convincingly demonstrated that muscle is not the primary pathologic factor in fibromyalgia. There were further studies reporting that fibromyalgia-chronic fatigue syndrome may follow well treated Lyme disease or mimic Lyme disease. The longest therapeutic trial to date in fibromyalgia demonstrated an initial modest effect of tricyclic medications, but at 6 months that efficacy was no longer evident. Investigation in both fibromyalgia and chronic fatigue syndrome now focuses on the central nervous system. The use of new technology, eg, neurohormonal assays and imaging such as single-photon emission computed tomography scan, may be important in understanding these elusive conditions.

 

Source: Goldenberg DL. Fibromyalgia, chronic fatigue syndrome, and myofascial pain syndrome. Curr Opin Rheumatol. 1995 Mar;7(2):127-35. http://www.ncbi.nlm.nih.gov/pubmed/7766493

 

Sleep, neuroimmune and neuroendocrine functions in fibromyalgia and chronic fatigue syndrome

Abstract:

The justification for disordered chronobiology for fibromyalgia and chronic fatigue syndrome (CFS) is based on the following evidence: The studies on disordered sleep physiology and the symptoms of fibromyalgia and CFS; the experimental studies that draw a link between interleukin-1 (IL-1), immune-neuroendocrine-thermal systems and the sleep-wake cycle; studies and preliminary data of the inter-relationships of sleep-wakefulness, IL-1, and aspects of peripheral immune and neuroendocrine functions in healthy men and in women during differing phases of the menstrual cycle; and the observations of alterations in the immune-neuroendocrine functions of patients with fibromyalgia and CFS (Moldofsky, 1993b, d). Time series analyses of measures of the circadian pattern of the sleep-wake behavioural system, immune, neuroendocrine and temperature functions in patients with fibromyalgia and CFS should determine whether alterations of aspects of the neuro-immune-endocrine systems that accompany disordered sleep physiology result in nonrestorative sleep, pain, fatigue, cognitive and mood symptoms in patients with fibromyalgia and CFS.

 

Source: Moldofsky H. Sleep, neuroimmune and neuroendocrine functions in fibromyalgia and chronic fatigue syndrome. Adv Neuroimmunol. 1995;5(1):39-56. http://www.ncbi.nlm.nih.gov/pubmed/7795892

 

Comparison of patients with chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS), fibromyalgia (FM), and multiple chemical sensitivities (MCS) are conditions associated with fatigue and a variety of other symptoms that appear to share many clinical and demographic features. Our objectives were to describe the similarities and differences among patients with CFS, FM, and MCS. Additional objectives were to determine how frequently patients with MCS and FM met the criteria for CFS and if they differed in their health locus of control.

METHODS: Demographic, clinical, and psychosocial measures were prospectively collected in 90 patients, 30 each with CFS, FM, and MCS. Patients were recruited from a university-based referral clinic devoted to the evaluation and treatment of chronic fatigue and three private practices. Variables included demographic features, symptoms characteristic of each condition, psychological complaints, a measure of health locus of control, and information on health care use.

RESULTS: Overall, the three patient groups were remarkably similar in demographic characteristics and the presence of specific symptoms. Patients with CFS and FM frequently reported symptoms compatible with MCS. Likewise, 70% of patients with FM and 30% of those with MCS met the criteria for CFS. Health care use was substantial among patients with CFS, FM, and MCS, with an average of 22.1, 39.7, and 23.3 visits, respectively, to a medical provider during the prior year. Health locus of control did not differ among the three populations.

CONCLUSIONS: In general, demographic and clinical factors and health locus of control do not clearly distinguish patients with CFS, FM, and MCS. Symptoms typical of each disorder are prevalent in the other two conditions.

Comment in: Chronic fatigue, fibromyalgia, and chemical sensitivity: overlapping disorders. [Arch Intern Med. 1995]

 

Source: Buchwald D, Garrity D. Comparison of patients with chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities. Arch Intern Med. 1994 Sep 26;154(18):2049-53. http://www.ncbi.nlm.nih.gov/pubmed/8092909