Category: Etiology

Abnormalities of sleep in patients with the chronic fatigue syndrome

Abstract:

OBJECTIVE: To determine whether patients with the chronic fatigue syndrome have abnormalities of sleep which may contribute to daytime fatigue.

DESIGN: A case-control study of the sleep of patients with the chronic fatigue syndrome and that of healthy volunteers.

SETTING: An infectious disease outpatient clinic and subjects’ homes.

SUBJECTS: 12 patients who met research criteria for the chronic fatigue syndrome but not for major depressive disorder and 12 healthy controls matched for age, sex, and weight.

MAIN OUTCOME MEASURES: Subjective reports of sleep from patients’ diaries and measurement of sleep patterns by polysomnography. Subjects’ anxiety, depression, and functional impairment were assessed by interview.

RESULTS: Patients with the chronic fatigue syndrome spent more time in bed than controls (544 min v 465 min, p < 0.001) but slept less efficiently (90% v 96%, p < 0.05) and spent more time awake after initially going to sleep (31.9 min v 16.6 min, p < 0.05). Seven patients with the chronic fatigue syndrome had a sleep disorder (four had difficulty maintaining sleep, one had difficulty getting to sleep, one had difficulty in both initiating and maintaining sleep, and one had hypersomnia) compared with none of the controls (p = 0.003). Those with sleep disorders showed greater functional impairment than the remaining five patients (score on general health survey 50.4% v 70.4%, p < 0.05), but their psychiatric scores were not significantly different.

CONCLUSIONS: Most patients with the chronic fatigue syndrome had sleep disorders, which are likely to contribute to daytime fatigue. Sleep disorders may be important in the aetiology of the syndrome.

 

Source: Morriss R, Sharpe M, Sharpley AL, Cowen PJ, Hawton K, Morris J. Abnormalities of sleep in patients with the chronic fatigue syndrome. BMJ. 1993 May 1;306(6886):1161-4. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1677618/ (Full article)

 

Inability of retroviral tests to identify persons with chronic fatigue syndrome, 1992

Abstract:

Chronic fatigue syndrome (CFS) is characterized by prolonged, debilitating fatigue. Although the cause of CFS unknown, CDC and researchers in other organizations have been investigating whether infection with a previously unidentified retrovirus might be an etiologic factor. Based on reports suggesting that retroviral infection with a human T-lymphotropic virus type 2 (HTLV-II)-like retrovirus or a spumavirus might be associated with CFS, some research and commercial laboratories developed assays to test specimens from persons with CFS. Even though the hypothesized association between infection with retroviruses and CFS has not been confirmed, these tests are used commonly to evaluate patients with CFS. This report summarizes the findings of a controlled, blinded study conducted in 1992 to determine whether three retroviral tests can distinguish serologically between patients with CFS (i.e., case-patients) and healthy controls.

 

Source: Centers for Disease Control and Prevention (CDC). Inability of retroviral tests to identify persons with chronic fatigue syndrome, 1992. MMWR Morb Mortal Wkly Rep. 1993 Mar 19;42(10):183, 189-90. http://www.ncbi.nlm.nih.gov/pubmed/8446093

 

Chronic fatigue and chronic fatigue syndrome: clinical epidemiology and aetiological classification

Abstract:

To determine the medical and psychiatric diagnoses that have an aetiological role in chronic fatigue we conducted a prospective study of 405 (65% women) patients who presented for evaluation with this chief complaint to an academic medical centre.

The average age was 38.1 years and the average duration of fatigue at entry in the study was 6.9 years. All patients were given comprehensive physical and laboratory evaluations and were administered a highly structured psychiatric interview. Psychiatric diagnoses explaining the chronic fatigue were identified in 74% of patients and physical disorders were diagnosed in 7% of patients.

The most common psychiatric conditions in this series were major depression, diagnosed in 58% of patients, panic disorder, diagnosed in 14% of patients, and somatization disorder, diagnosed in 10% of patients. Primary sleep disorders, diagnosed in 2% patients, and chronic infections, confirmed in 1.6% patients, explained the majority of cases whose chronic fatigue was attributed to a physical disorder.

Thirty per cent of patients met the criteria used to define the chronic fatigue syndrome (CFS). Compared with age- and gender-matched control subjects with chronic fatigue, CFS patients had a similarly high prevalence of current psychiatric disorders (78% versus 82%), but were significantly more likely to have somatization disorder (28% versus 5%) and to attribute their illness to a viral infection (70% versus 33%).

We conclude that most patients with a chief complaint of chronic fatigue, including those exhibiting the features of CFS, suffer from standard mood, anxiety and/or somatoform disorders. Careful research is still needed to determine whether CFS is a distinct entity or a variant of these psychiatric illness.

 

Source: Manu P, Lane TJ, Matthews DA. Chronic fatigue and chronic fatigue syndrome: clinical epidemiology and aetiological classification. Ciba Found Symp. 1993;173:23-31; discussion 31-42. http://www.ncbi.nlm.nih.gov/pubmed/8491100

 

Persistence of enterovirus RNA in muscle biopsy samples suggests that some cases of chronic fatigue syndrome result from a previous, inflammatory viral myopathy

Abstract:

Molecular hybridization using an enterovirus group specific probe detected virus RNA in muscle biopsy samples from 25 of 96 cases of inflammatory muscle disease and similarly from 41 of 158 cases of postviral fatigue syndrome (PFS).

Enterovirus RNA was detected in only two of 152 samples of control muscle. The inflammatory myopathy group comprised patients with polymyositis (PM), juvenile dermatomyositis (JDM) or adult dermatomyositis (DM), and all showed the presence of an inflammatory infiltrate and fiber necrosis on histological examination of a muscle biopsy sample.

In contrast, muscle samples from the PFS group were histologically normal except for non-specific changes such as occasional single fiber atrophy. By analogy with enteroviral myocarditis, which can progress to a post-inflammatory disease with persistence of virus in myocardium and disposes to the rapid development of dilated cardiomyopathy, we propose that PFS syndrome may be a sequela of a previous inflammatory viral myopathy.

 

Source: Bowles NE, Bayston TA, Zhang HY, Doyle D, Lane RJ, Cunningham L, Archard LC. Persistence of enterovirus RNA in muscle biopsy samples suggests that some cases of chronic fatigue syndrome result from a previous, inflammatory viral myopathy. J Med. 1993;24(2-3):145-60. http://www.ncbi.nlm.nih.gov/pubmed/8409778

 

Investigation of retroviral involvement in chronic fatigue syndrome

Abstract:

Within the last few years significant efforts have been made to identify objective reliable diagnostic markers from individuals with chronic fatigue syndrome (CFS).

We report the absence of a previously described retroviral marker (HTLV-II gag) in a blinded study of CFS cases. Even with excellent reproducible sensitivities, this marker failed in repeated attempts to distinguish cases from controls. In addition, four other retroviruses (simian T cell leukaemia virus, human spumavirus, bovine leukaemia virus and simian retrovirus) were examined for their presence in these CFS cases and found to be absent.

Our findings suggest that these agents, at least as markers, are non-distinguishing for CFS and that other factors may be confounding the resolution of an aetiology to this syndrome.

 

Source: Folks TM, Heneine W, Khan A, Woods T, Chapman L, Schonberger L. Investigation of retroviral involvement in chronic fatigue syndrome. Ciba Found Symp. 1993;173:160-6; discussion 166-75. http://www.ncbi.nlm.nih.gov/pubmed/8387909

 

Viral infection and its causative role for chronic fatigue syndrome

Abstract:

Patients with chronic fatigue syndrome (CFS), of unknown etiology, have been increasingly reported. This syndrome is characterized by debilitating fatigue, lymphadenopathy, and fever. Herein, I focus on and review this syndrome from the view point of the causative role of viral infection. Since the symptoms of CFS are similar to those of chronic infectious mononucleosis (CIM) or chronic Epstein-Barr virus infection (CEBV), the role of EBV has been intensively studied. The etiological relationship between EBV and CFS, however, is questioned, like other lymphotropic viruses, including human retroviruses, adenoviruses and human herpesvirus 6. Additionally, severe chronic active EBV infection syndrome (SCAEBV) is also discussed in this review because symptoms of this disorder are similar to those of CFS but more severe in degree. Currently, the cause(s) and treatment of CFS are enigmatic and require further research and multidisciplinary study.

 

Source: Okano M. Viral infection and its causative role for chronic fatigue syndrome. Nihon Rinsho. 1992 Nov;50(11):2617-24. [Article in Japanese] http://www.ncbi.nlm.nih.gov/pubmed/1337559

 

Chronic fatigue syndrome and virus infection: human herpesvirus 6 (HHV-6) infection

Abstract:

Chronic fatigue syndrome (CFS) is newly-recognized disease characterized by chronic and debilitating fatigue. It has been suggested that viral infection may be involved in this syndrome from the results of clinical examination, including increased activity of 2′,5′-synthetase in leukocytes of patients. The following viruses have been reported as etiologic agents of this disease. First, many studies have found elevated levels of IgG to viral capsid antigen and early antigens to Epstein-Barr virus (EBV), but low titer or absence of antibody to EBV-associated nuclear antigen. Second, the enteroviruses have also been implicated as possible causative agent of CFS, because virus could be isolated from patients. Recently it was also reported that antibodies to human T-lymphotropic virus (HTLV) and HTLV type II (HTLV-II) gag sequence were detectable in patients. Finally several reports state that human herpesvirus 6 (HHV-6) could be isolated from CFS patients in the high frequency. In conclusion, it is still early to identify the etiologic agent from these reports, and more effort is needed.

 

Source: Yamanishi K. [Chronic fatigue syndrome and virus infection: human herpesvirus 6 (HHV-6) infection]. Nihon Rinsho. 1992 Nov;50(11):2612-6. [Article in Japanese] http://www.ncbi.nlm.nih.gov/pubmed/1337558

 

Assessment of regional cerebral perfusion by 99Tcm-HMPAO SPECT in chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is a severely disabling illness of uncertain aetiology. It is characterized by a chronic, sustained or fluctuating sense of debilitating fatigue without any other known underlying medical conditions. It is also associated with both somatic and neuropsychological symptoms. Both physical and laboratory findings are usually unremarkable.

Regional cerebral blood flow (rCBF) was assessed in 60 clinically defined CFS patients and 14 normal control (NC) subjects using 99Tcm-hexamethylpropyleneamine oxime (99Tcm-HMPAO) single photon emission computed tomography (SPECT). Compared with the NC group, the CFS group showed significantly lower cortical/cerebellar rCBF ratios, throughout multiple brain regions (P < 0.05). Forty-eight CFS subjects (80%) showed at least one or more rCBF ratios significantly less than normal values.

The major cerebral regions involved were frontal (38 cases, 63%), temporal (21 cases, 35%), parietal (32 cases, 53%) and occipital lobes (23 cases, 38%). The rCBF ratios of basal ganglia (24 cases, 40%) were also reduced. 99Tcm-HMPAO brain SPECT provided objective evidence for functional impairment of the brain in the majority of the CFS subjects. The findings may not be diagnostic of CFS but 99Tcm-HMPAO SPECT may play an important role in clarifying the pathoaetiology of CFS. Further studies are warranted.

 

Source: Ichise M, Salit IE, Abbey SE, Chung DG, Gray B, Kirsh JC, Freedman M. Assessment of regional cerebral perfusion by 99Tcm-HMPAO SPECT in chronic fatigue syndrome. Nucl Med Commun. 1992 Oct;13(10):767-72. http://www.ncbi.nlm.nih.gov/pubmed/1491843

 

Fatigue syndromes: new thoughts and reinterpretation of previous data

Abstract:

Recently, the author has identified 19 patients who have complained of marked fatigue that had abnormal responses to copper test bracelets or necklaces. At this time, 8 have been shown to have at least one enzyme deficiency in the heme pathway. These patients have been diagnosed with multiple sclerosis, chronic fatigue syndrome and other non-specific diagnoses. A lengthy but still limited review of the literature was performed regarding the following conditions: multiple sclerosis (MS), hepatic porphyria (HP), chronic fatigue syndrome (CFS) and paralytic polio (PP). The text will focus on similar epidemiologies, laboratory findings and clinical courses. Copper as a common but not unique etiologic agent will be discussed; as will the heme pathway, a biologic process that may be disordered in all.

 

Source: Downey DC. Fatigue syndromes: new thoughts and reinterpretation of previous data. Med Hypotheses. 1992 Oct;39(2):185-90. http://www.ncbi.nlm.nih.gov/pubmed/1461185

 

Culture and somatic experience: the social course of illness in neurasthenia and chronic fatigue syndrome

Abstract:

An anthropological view of culture and somatic experience is presented through elaboration of the notion that illness has a social course. Contemporary anthropology locates culture in local worlds of interpersonal experience. The flow of events and processes in these local worlds influences the waxing and waning of symptoms in a dialectic involving body and society over time.

Conversely, symptoms serve as a medium for the negotiation of interpersonal experience, forming a series of illness-related changes in sufferers’ local worlds. Thus, somatic experience is both created by and creates culture throughout the social course of illness. Findings from empirical research on neurasthenia in China, and chronic fatigue syndrome (CFS) in the United States, corroborate this formulation. Attributions of illness onset to social sources, the symbolic linking of symptoms to life context, and the alleviation of distress with improvement in circumstances point to the sociosomatic mediation of sickness.

Transformations occasioned by illness in the lives of neurasthenic and CFS patients confirm the significance of bodily distress as a vehicle for the negotiation of change in interpersonal worlds. An indication of some of the challenges anthropological thinking poses for psychosomatic medicine concludes the discussion.

 

Source: Ware NC, Kleinman A. Culture and somatic experience: the social course of illness in neurasthenia and chronic fatigue syndrome. Psychosom Med. 1992 Sep-Oct;54(5):546-60. http://www.ncbi.nlm.nih.gov/pubmed/1438658