Tag: risk factors

The natural history of concurrent sick building syndrome and chronic fatigue syndrome

Abstract:

An outbreak of chronic fatigue syndrome linked with sick building syndrome was recently described as a new association. Whether chronic fatigue syndrome acquired in this setting tends to remit or, as sporadic cases often do, persist, is unknown.

To clarify the natural history of chronic fatigue syndrome in association with sick building syndrome the 23 individuals involved in the outbreak were interviewed four years after the onset. In the previous interview one year after the onset of symptoms, 15 (including 5 with chronic fatigue syndrome and 10 with idiopathic chronic fatigue) of the 23 noted fatigue. Three years later 10 of the 15 were “fatigue free” or “much improved”.

Five were only “some better”, “the same”, or “worse”. Three of the five people previously diagnosed with chronic fatigue syndrome were “much improved” (two) or “fatigue free” (one). The remaining two were seriously impaired, homebound and unable to work.

The 10 individuals with substantially improved fatigue (three of the five with chronic fatigue syndrome and seven of the 10 with idiopathic chronic fatigue) were more likely to have noted improvement in nasal and sinus symptoms, sore throats, headaches, and tender cervical lymph nodes when compared to those with a lingering significant fatigue (p < 0.001). Upper respiratory symptoms and headaches improved in those with reduced fatigue but remained problematic in those with persisting significant fatigue.

We conclude that the fatigue related to sick building syndrome, including chronic fatigue syndrome, is significantly more likely to improve than fatigue identified in sporadic cases of chronic fatigue syndrome.

 

Source: Chester AC, Levine PH. The natural history of concurrent sick building syndrome and chronic fatigue syndrome. J Psychiatr Res. 1997 Jan-Feb;31(1):51-7. http://www.ncbi.nlm.nih.gov/pubmed/9201647

 

Fatiguing illness among employees in three large state office buildings, California, 1993: was there an outbreak?

Abstract:

The objective was to determine if a cluster of chronic fatigue syndrome (CFS)-like illness had occurred among employees in two large state office buildings in northern California, and to identify risk factors for and features of fatiguing illness in this population.

DESIGN: case-control study.

POPULATION AND SETTING: Over 3300 current employees in two state office buildings and employees in a comparable “control” building. Information was collected on demographic and occupational variables, the occurrence of fatiguing illness for at least one month in the previous year, and the presence of 36 symptoms. A total of 3312 (82%) of 4035 employees returned questionnaires. Overall, 618 (18.7%) persons reported fatigue lasting at least one month; including 382 (11.5%) with fatigue of at least six months’ duration and 75 (2.3%) with symptoms compatible with a CFS-like illness.

Independent risk factors for fatigue lasting one month or longer were found to be Native American ethnicity (OR 2.4, CI 1.1,5.3), Hispanic ethnicity (OR 1.7, CI 1.3,2.3), female sex (OR 1.5, CI 1.2,1.9), gross household incomes of less than $50,000 (OR 1.3, CI 1.1,1.6), and less than a college education (OR 1.3, CI 1.1,1.6). Similar risks were observed for persons who reported fatigue lasting six months or longer. Female sex (OR 3.2, CI 1.7, 6.4) was the only independent risk factor found for those persons classified as having a CFS-like illness. Case prevalence rates for all three categories of fatigue, as determined by multivariate analysis, were not significantly different among buildings.

Despite finding a substantial number of employees with fatiguing illness in the two state office buildings, the prevalence was not significantly different than that for a comparable control building. Previously unidentified risk factors for fatigue of at least one month and at least six months identified in this population included Hispanic ethnicity, not having completed college, and income below $50,000.

 

Source: Shefer A, Dobbins JG, Fukuda K, Steele L, Koo D, Nisenbaum R, Rutherford GW. Fatiguing illness among employees in three large state office buildings, California, 1993: was there an outbreak? J Psychiatr Res. 1997 Jan-Feb;31(1):31-43. http://www.ncbi.nlm.nih.gov/pubmed/9201645

 

Epidemiologic advances in chronic fatigue syndrome

Abstract:

Epidemiologic studies of chronic fatigue syndrome (CFS) have been hampered by the absence of a specific diagnostic test, but with increasing interest in this disorder there has been a greater understanding of the risk factors, illness patterns, and other aspects of this multisystem disorder.

Working case definitions have been developed for research purposes but they have continued to change over time and have not always been utilized precisely by various investigators. This has been a major factor in the widely varying estimates of prevalence rates, but two different studies using the same working definition and including a medical work-up have estimated the prevalence to be approximately 200/100,000. Clusters of CFS cases, which appear to be related to earlier reports of “epidemic neuromyasthenia”, have attracted considerable attention and appear to be well documented, although investigated with varying methodology and often with dissimilar case definitions.

Risk factors for cases occurring in clusters and sporadically appear to be similar, the most consistent ones being female gender and the co-existence of some form of stress, either physical or psychological. The prognosis of CFS is difficult to predict, although cases occurring as part of clusters appear to have a better prognosis as a group than sporadic cases, and those with an acute onset have a better prognosis than those with gradual onset.

It is highly unlikely that there is a single agent, infectious or noninfectious, that is responsible for more than a small proportion of CFS cases and, at the present time, the risk factors for developing CFS appear to lie more prominently in the host rather than the environment.

 

Source: Levine PH. Epidemiologic advances in chronic fatigue syndrome. J Psychiatr Res. 1997 Jan-Feb;31(1):7-18. http://www.ncbi.nlm.nih.gov/pubmed/9201643

 

Psychosocial risk factors for chronic fatigue and chronic fatigue syndrome following presumed viral illness: a case-control study

Abstract:

This study investigated psychosocial morbidity, coping styles and health locus of control in 64 cases with and without chronic fatigue identified from a cohort of primary care patients recruited 6 months previously with a presumed, clinically diagnosed viral illness. A significant association between chronic fatigue and psychosocial morbidity, somatic symptoms and escape-avoidance coping styles was shown.

Chronic fatigue cases were significantly more likely to have a past psychiatric history and a current psychiatric diagnosis based on a standardized clinical interview. Twenty-three of the cases fulfilled criteria for chronic fatigue syndrome (CFS). Such cases were significantly more fatigued than those not fulfilling criteria, but had little excess psychiatric disorder.

A principal components analysis provided some evidence for chronic fatigue being separable from general psychosocial morbidity but not from the tendency to have other somatic complaints. Past psychiatric history and psychological distress at the time of the viral illness were risk factors for psychiatric ‘caseness’ 6 months later, while presence of fatigue, psychologising attributional style and sick certification were significant risk factors for CFS. These findings extend a previous questionnaire study of predictors of chronic ‘post-viral’ fatigue.

 

Source: Cope H, Mann A, Pelosi A, David A. Psychosocial risk factors for chronic fatigue and chronic fatigue syndrome following presumed viral illness: a case-control study. Psychol Med. 1996 Nov;26(6):1197-209. http://www.ncbi.nlm.nih.gov/pubmed/8931166

 

Chronic fatigue: risk factors for symptom persistence in a 2 1/2-year follow-up study

Abstract:

BACKGROUND: The prolonged disability of patients suffering from chronic fatigue may be due to sustaining factors that are independent of the cause and subject to intervention. This study reexamined a cohort of patients with chronic fatigue to define medical and psychiatric predictors of persistent symptoms.

METHODS: Seventy-eight patients with chronic fatigue present for 6 months or more (not required to meet the Centers for Disease Control case definition for chronic fatigue syndrome [CFS]) completed a self-report, follow-up questionnaire to measure the overall improvement or worsening of their condition at a mean of 2.5 years after their initial examination. At the time of initial evaluation, patients underwent a structured psychiatric examination, physical examination, laboratory studies, and self-report measures of psychological distress and functional disability. The psychiatric examination queried the patient about 28 somatic symptoms that are separate from those associated with CFS. Discriminant analysis was used to determine which variables present at the initial examination were significant predictors of persistent symptoms and disability at 2.5 years.

RESULTS: The factors most important at the time of initial presentation in predicting persistent illness were: (1) more than eight medically unexplained physical symptoms separate from those associated with CFS case definition; (2) lifetime history of dysthymia; (3) duration of chronic fatigue symptoms greater than 1.5 years; (4) less than 16 years of formal education; and (5) age older than 38 years. None of the results of the initial physical examination, or immunologic, general laboratory, or viral antibody measurements were significant in predicting persistence of symptoms. Recovery rates for those who met the criteria for CFS by either of two case definitions were lower than the rate of noncases, but the differences were not statistically significant. The five aforementioned variables formed a significant discriminative function, correctly classifying 78% of those who recovered and 74% of those with persistent symptoms.

CONCLUSIONS: At initial examination, patients with chronic fatigue, more than eight medically unexplained physical symptoms (excluding symptoms in the case criteria for CFS), a lifetime history of dysthymic disorder, longer than 1.5 years of chronic fatigue, less than 16 years of formal education, and who were older than 38 years were the most likely to have persistence of symptoms of chronic fatigue at the 2.5-year follow-up.

 

Source: Clark MR, Katon W, Russo J, Kith P, Sintay M, Buchwald D. Chronic fatigue: risk factors for symptom persistence in a 2 1/2-year follow-up study. Am J Med. 1995 Feb;98(2):187-95. http://www.ncbi.nlm.nih.gov/pubmed/7847436

 

Predictors of chronic “postviral” fatigue

Abstract:

We set out to determine the relation between a general practitioner (GP) diagnosis of viral illness and development of chronic fatigue 6 months later. 618 subjects who attended GPs clinics in London, south, and southwest England and who received a diagnosis of viral illness were followed prospectively and fatigue was assessed by questionnaire after 6 months. At presentation, GPs recorded fatigue in 62.6% of subjects, usually since the onset of symptoms. 502 (81.2%) subjects completed the 6-month questionnaire, of whom 88 (17.5%) met criteria for chronic fatigue and 65 (12.9%) had no reported fatigue before the viral illness.

Compared with a similar group of non-postviral GP attenders, the risk ratio for chronic fatigue in the present cohort was 1.45 (95% CI 1.14-2.04). Infective symptoms did not predict fatigue 6 months later. Psychiatric morbidity, belief in vulnerability to viruses, and attributional style at initial presentation were all associated with self-designated postviral fatigue.

Logistic regression showed that somatic attributional style, less definite diagnosis by the GP, and sick certification were the only significant predictors of chronic fatigue after viral infection when other factors were controlled for. Chronic severe fatigue 6 months after GP-diagnosed viral illness is related to symptom-attributional style and doctor behaviour, rather than to features of the viral illness. Some subjects with apparent postviral fatigue had complained of tiredness before their presentation with a viral illness.

Comment in:

Chronic fatigue syndrome. [Lancet. 1994]

Chronic fatigue syndrome. [Lancet. 1994]

 

Source: Cope H, David A, Pelosi A, Mann A. Predictors of chronic “postviral” fatigue. Lancet. 1994 Sep 24;344(8926):864-8. http://www.ncbi.nlm.nih.gov/pubmed/7916407

 

Concurrent sick building syndrome and chronic fatigue syndrome: epidemic neuromyasthenia revisited

Abstract:

Sick building syndrome (SBS) is usually characterized by upper respiratory complaints, headache, and mild fatigue. Chronic fatigue syndrome (CFS) is an illness with defined criteria including extreme fatigue, sore throat, headache, and neurological symptoms.

We investigated three apparent outbreaks of SBS and observed another more serious illness (or illnesses), characterized predominantly by severe fatigue, that was noted by 9 (90%) of the 10 teachers who frequently used a single conference room at a high school in Truckee, California; 5 (23%) of the 22 responding teachers in the J wing of a high school in Elk Grove, California; and 9 (10%) of the 93 responding workers from an office building in Washington, D.C.

In those individuals with severe fatigue, symptoms of mucous membrane irritation that are characteristic of SBS were noted but also noted were neurological complaints not typical of SBS but quite characteristic of CFS. We conclude that CFS is often associated with SBS.

 

Source: Chester AC, Levine PH. Concurrent sick building syndrome and chronic fatigue syndrome: epidemic neuromyasthenia revisited. Clin Infect Dis. 1994 Jan;18 Suppl 1:S43-8. http://www.ncbi.nlm.nih.gov/pubmed/8148452

 

The chronic fatigue syndrome

Abstract:

CFIDS (chronic fatigue and immune disfunction syndrome) is also known as CFS (chronic fatigue syndrome), CEBV (chronic Epstein-Barr virus), M.E. (myalgic encephalomyelitis), yuppie flu and by other names.

It is a complex illness characterized by incapacitating fatigue (experienced as exhaustion and extremely poor stamina), neurological problems and a constellation of symptoms that can resemble many disorders, including; mononucleosis, multiple sclerosis, fibromyalgia, AIDS-related complex (ARC) and autoimmune diseases such as lupus. These symptoms tend to wax and wane, but any often severely debilitating and may last for many months or years. All sections of the population (including children) are at risk, but women under 45 seem to be most susceptible.

The investigators suggest that CFIDS results from dysfunction of the immune system. The exact nature of this dysfunction is not yet well defined, but it can generally be viewed as an unregulated or overactive state which is responsible for most of the symptoms. There is also evidence of some immune suppression in CFIDS. None of the treatments is consistently satisfactory, but some may be helpful: psychotherapy, physiotherapy, exercise programs, acupunctures, small doses of antidepressants, etc.

 

Source: Artsimovich NG, Chugunov VS, Kornev AV, Ivanova TM, Chugunov AV, Oprishchenko MA. The chronic fatigue syndrome. Zh Nevrol Psikhiatr Im S S Korsakova. 1994;94(5):47-50. [Article in Russian] http://www.ncbi.nlm.nih.gov/pubmed/7900453

 

Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes

Abstract:

375 patients with chronic fatigue syndrome (CFS) were examined using a standardized questionnaire and subsequent interview on 11 risk factors and 45 symptoms. Additionally immunologic, serologic, toxicologic, neuroradiologic, neurophysiologic and cardiologic investigations were performed.

Immunologic tests showed cellular immunodeficiences particularly in functional regard (pathological lymphocyte stimulation in 50% of the patients, disorders of granulocyte function in 44%). Furthermore variable deviations were found in the lymphocyte subpopulations (CD3, CD4, CD8, CD19, DR, Leu 11 + 19).

In the humoral part tendencies to low IgG-3- and IgG-1-subclass-levels occurred (59% respectively 11% of the patients) also as decreases in complement system (CH50, C3, C4, C1-esterase-inhibitor). In the group of activation markers and cytokines 42% of the investigated patients had circulating immune complexes (CIC), 47% increases of tumor-necrosis-factor (TNF-a) and 21% increases of soluble interleukin-2-receptor (IL-2-R).

The increased occurrence of autoantibodies in the CFS-patients (specially antinuclear anti-bodies [ANA], microsomal thyroid antibodies) suggest, that CFS is associated with or the beginning of manifest autoimmune disease.

Under the pathogens 78% of the patients had a striking serological constellation of Epstein-Barr-Virus (EBV-EA positive, low EBNA-titers), in the HHV-6-Virus 47% showed increased antibody-titers. Tests on further herpes viruses and on Borreliae, Chlamydiae, Candida and Amoebae were positive in 8 to 36% of the examined patients. Furthermore there were found variable deficits of vitamins and trace elements also as hormonal disturbances.

In 26% of the patients there were hints of pollutants (e.g. wood preservatives), in 32 patients blood-levels of pentachlorphenol (PCP) and gamma-hexachlorcyclohexan (γ-HCH, lindan) were measured, which showed vanable increases.

178 (83%) of 225 investigated patients showed disturbances of perfusion in cerebral SPECT imaging, 65 (29%) of 218 patients cerebral punctuate signal changes in cranial magnetic resonance imaging (MRI).

Neurophysiologic measurements (motor evoked potentials, MEP) showed in about 50% of 112 patients prolonged central motor conduction times. 62 patients were additionally investigated by myocardial SPECT-imaging, which was abnormal under exercise in 73%. Our data confirm the concept, that CFS must be considered as a complex psycho-neuro-immunological disorder.

 

Source: Hilgers A, Frank J. Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes. Wien Med Wochenschr. 1994;144(16):399-406.[Article in German] http://www.scopus.com/record/display.uri?eid=2-s2.0-0027940724&origin=inward&txGid=0

and http://www.ncbi.nlm.nih.gov/pubmed/7856214

 

 

Chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is defined by symptoms and diagnosed without any objective diagnostic tests. Risk factors for developing CFS may include infection, psychiatric disorders, and allergies. Modest dysfunction of multiple organ systems, including the immune, central nervous, endocrine, and muscular systems, have been identified in cases of CFS. Symptoms of various organic, psychiatric, and poorly understood disorders overlap those of CFS. There is no known cure for CFS; however, exercise, counseling, and medications may provide symptomatic relief.

 

Source: Klonoff DC. Chronic fatigue syndrome. Clin Infect Dis. 1992 Nov;15(5):812-23. http://www.ncbi.nlm.nih.gov/pubmed/1445980