Chronic fatigue syndrome in the community. Prevalence and associations

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is a poorly understood condition, apparently related to both psychiatric disturbance and infectious illness. Little progress has been made in identifying aetiology, owing to a lack of epidemiological studies using case-definition criteria.

METHOD: A community postal survey of a random sample of over 1000 patients registered at a local health centre comprised a fatigue questionnaire and the 12-item General Health Questionnaire (GHQ).

RESULTS: Total fatigue scores were modestly higher in women than men. Fatigue was most frequently attributed to psychosocial factors. Fatigue and GHQ scores were strongly correlated. Two men and two women satisfied British criteria for CFS, a prevalence of 0.56% (95% Cl 0.16-1.47%); three were probable psychiatric cases.

CONCLUSIONS: Previously reported sociodemographic associations of CFS may reflect medical referral patterns. A strong association exists with psychological morbidity, but relabelling CFS as a psychiatric disorder is not justified.

 

Source: Lawrie SM, Pelosi AJ. Chronic fatigue syndrome in the community. Prevalence and associations. Br J Psychiatry. 1995 Jun;166(6):793-7. http://www.ncbi.nlm.nih.gov/pubmed/7663830

 

Chronic fatigue syndrome

Comment on: Chronic fatigue syndrome: a follow up study. [J Neurol Neurosurg Psychiatry. 1994]

 

Chronic fatigue syndrome: a follow up study by Bonner et al’ reported that 47 patients initially diagnosed with “chronic fatigue” were contacted for follow up four years later. The authors indicated that “These patients were initially assessed before the current criteria for chronic fatigue syndrome became available, but most would have satisfied the criteria retrospectively” (p 617). At the outset, all patients were offered cognitive behavioural treatment and some were offered antidepressant medications. Each patient then made a decision to either undergo or decline cognitive behavioural treatment. Four years later, those patients who reported functional improvement were more likely to have elected to receive the cognitive behavioural treatment. Additionally, patients in the group that did not report any functional improvement were more likely to score higher on measures of depression.

The US Centers for Disease Control and Prevention (CDC) case definition,2 the proposed revisions to the CDC case definition,3 and the guidelines for research set forth by Sharpe et al4 were cited, but the researchers did not make it clear as to which criteria were used to diagnose which patients. Thus it is unknown whether uniform criteria were applied to diagnose all patients at the outset. Moreover, the authors did not specify just how many of the initial 47 patients met any of the cited criteria for chronic fatigue syndrome, as opposed to chronic fatigue. In short, they did not differentiate the exact number of chronic fatigue syndrome v chronic fatigue cases.

Only 29 of the original 47 patients (62%) agreed to be interviewed for the follow up. Thus 18 (38%) of the original patients were not included in the outcome data, where 10 subjects reported little or no improvement and 19 subjects reported improvement or recovery. The authors acknowledged that the small patient sample size constituted a methodological shortcoming, but nevertheless concluded “that there is a strong association between successful completion of [cognitive] treatment and the absence of functional disability at the four year follow up” (p 620). They further suggest that costs associated with long term disability could be reduced by the utilisation of cognitive therapy in the treatment of chronic fatigue syndrome. We would like to emphasise that the small patient sample size, together with the lack of availability of almost 40% of the initial patients for interview at follow up, make such conclusions highly inappropriate.

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1073573/pdf/jnnpsyc00030-0116.pdf

 

Source: Lipkin DM, Robin R, Vasquez L, Plioplys AV, Plioplys S. Chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 1995 Jun;58(6):764-5. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1073573/

 

Chronic fatigue syndrome: a cognitive approach

Abstract:

Observations concerning the characteristics of patients who presented to a medical clinic with a principal complaint of chronic medically unexplained fatigue (Chronic Fatigue Syndrome or CFS) are described, including the cognitions (thoughts and assumptions) elicited from a sample of these patients who were treated using cognitive behavioural therapy. On the basis of these observations a cognitive theory of the aetiology of CFS is proposed. These observations have implications for the treatment of patients with CFS.

 

Source: Surawy C, Hackmann A, Hawton K, Sharpe M. Chronic fatigue syndrome: a cognitive approach. Behav Res Ther. 1995 Jun;33(5):535-44. http://www.ncbi.nlm.nih.gov/pubmed/7598674

 

Postinfectious fatigue: prospective cohort study in primary care

Abstract:

The idea that chronic fatigue has an infectious origin has become popular, but the main evidence for such an association has come from retrospective case-control studies, which are subject to ascertainment bias. We report a prospective study of the outcome of clinically diagnosed infections in patients presenting to UK general practitioners.

Questionnaires assessing fatigue and psychiatric morbidity were sent to all patients aged 18-45 years in the study practices. The prevalence of chronic fatigue and chronic fatigue syndrome was then ascertained among 1199 people aged 18-45 who presented to the general practitioners with symptomatic infections and in 1167 people who attended the surgeries for other reasons. 84% were followed up at 6 months. 9.9% of cases and 11.7% of controls reported chronic fatigue (odds ratio 1.0 [95% CI 0.6-1.1]). There were no differences in the proportions who met various criteria for chronic fatigue syndrome. No effect of infection was noted when we excluded subjects who reported fatigue or psychological morbidity at the baseline screening.

The strongest independent predictors of postinfectious fatigue were fatigue assessed before presentation with clinical infection (3.0 [1.9-4.7]) and psychological distress before presentation (1.8 [1.2-2.9]) and at presentation with the acute infection (1.8 [1.1-2.8]). There was no effect of sex or social class. Our study shows no evidence that common infective episodes in primary care are related to the onset of chronic fatigue or chronic fatigue syndrome.

Comment in:

Viral illness and chronic fatigue (syndrome). [Lancet. 1995]

Viral illness and chronic fatigue (syndrome) [Lancet. 1995]

Viral illness and chronic fatigue (syndrome). [Lancet. 1995]

Viral illness and chronic fatigue (syndrome) [Lancet. 1995]

Viral illness and chronic fatigue (syndrome). [Lancet. 1995]

 

Source: Wessely S, Chalder T, Hirsch S, Pawlikowska T, Wallace P, Wright DJ. Postinfectious fatigue: prospective cohort study in primary care. Lancet. 1995 May 27;345(8961):1333-8. http://www.ncbi.nlm.nih.gov/pubmed/7752755

 

Chronic fatigue syndrome: a clinical and laboratory study with a well matched control group

Abstract:

OBJECTIVE: To investigate the relation between severity of complaints, laboratory data and psychological parameters in patients with chronic fatigue syndrome (CFS).

SUBJECTS: Eighty-eight patients with CFS and 77 healthy controls matched for age, sex and geographical area.

METHODS: Patients and controls visited our outpatient clinic for a detailed medical history, physical examination and psychological tests: Checklist Individual Strength (CIS). Beck Depression Inventory (BDI) and Sickness Impact Profile (SIP). Venous blood was drawn for a complete blood cell count, serum chemistry panel, C-reactive protein and serological tests on a panel of infectious agents.

RESULTS: All patients fulfilled the criteria for CFS as described by Sharpe et al. (J R Soc Med 1991; 84: 118-21), only 18 patients (20.5%) fulfilled the CDC criteria. The outcome of serum chemistry tests and haematological tests were within the normal range. No significant differences were found in the outcome of serological tests. Compared to controls, significant differences were found in the results on the CIS, the BDI, and the SIP. These results varied with the number of complaints (CDC criteria). When the number of complaints was included as the covariate in the analysis, there were no significant differences on fatigue severity, depression, and functional impairment between patients who fulfilled the CDC criteria and patients who did not.

CONCLUSION: It is concluded that the psychological parameters of fatigue severity, depression and functional impairment are related to the clinical severity of the illness. Because the extensive panel of laboratory tests applied in this study did not discriminate between patients and controls, it was not possible to investigate a possible relation between the outcomes of psychological and laboratory testing.

Comment in: Chronic fatigue syndrome: a clinical and laboratory study with a well-matched control group. [J Intern Med. 2004]

 

Source: Swanink CM, Vercoulen JH, Bleijenberg G, Fennis JF, Galama JM, van der Meer JW. Chronic fatigue syndrome: a clinical and laboratory study with a well matched control group. J Intern Med. 1995 May;237(5):499-506. http://www.ncbi.nlm.nih.gov/pubmed/7738491

 

The Multidimensional Fatigue Inventory (MFI) psychometric qualities of an instrument to assess fatigue

Abstract:

The Multidimensional Fatigue Inventory (MFI) is a 20-item self-report instrument designed to measure fatigue. It covers the following dimensions: General Fatigue, Physical Fatigue, Mental Fatigue, Reduced Motivation and Reduced Activity. This new instrument was tested for its psychometric properties in cancer patients receiving radiotherapy, patients with the chronic fatigue syndrome, psychology students, medical students, army recruits and junior physicians. We determined the dimensional structure using confirmatory factor analyses (LISREL’s unweighted least squares method). The hypothesized five-factor model appeared to fit the data in all samples tested (AGFIs > 0.93). The instrument was found to have good internal consistency, with an average Cronbach’s alpha coefficient of 0.84. Construct validity was established after comparisons between and within groups, assuming differences in fatigue based on differences in circumstances and/or activity level. Convergent validity was investigated by correlating the MFI-scales with a Visual Analogue Scale measuring fatigue (0.22 < r < 0.78). Results, by and large, support the validity of the MFI.

 

Source: Smets EM, Garssen B, Bonke B, De Haes JC. The Multidimensional Fatigue Inventory (MFI) psychometric qualities of an instrument to assess fatigue. J Psychosom Res. 1995 Apr;39(3):315-25. http://www.ncbi.nlm.nih.gov/pubmed/7636775

 

The chronically fatigued patient

Abstract:

This article illustrates that the diagnostic evaluation as well as the management of the patient presenting with chronic fatigue can be done in an orderly manner. If a medical illness is the cause of the patient’s fatigue, this is usually evident on initial presentation. A thorough history and complete physical examination, in conjunction with some screening laboratory tests, can rule out most medical causes of fatigue, and any remaining cases declare themselves over the next several visits. If a medical cause is not evident, a further “fishing expedition” is fruitless.

Psychiatric illness, such as depression or generalized anxiety disorder, accounts for another significant proportion of cases of chronic fatigue. As with medical illness, psychiatric illness should be suspected based on history and is not a diagnosis of exclusion. Some patients presenting with chronic fatigue have a history and symptom pattern consistent with the diagnosis of CFS. The cause of this syndrome is controversial and is still unknown. The clinician, however, can offer the patient care in an environment that is respectful of their physical and psychological discomfort and can provide significant symptomatic improvement to the patient.

Lastly, some patients with fatigue do not fit any diagnostic category, including CFS. As with many other common complaints, such as headaches or abdominal pain, although a diagnosis may not be given to the patient, the clinician can do a lot to reassure the patient and assist the patient in living with his or her symptoms. As Solberg eloquently wrote: “[E]valuation of the fatigued patient requires all of a physician’s best attributes–a broad view of disease, psychosocial sensitivity, and a good ongoing relationship with the patient.”

 

Source: Epstein KR. The chronically fatigued patient. Med Clin North Am. 1995 Mar;79(2):315-27. http://www.ncbi.nlm.nih.gov/pubmed/7877393

 

General practitioners’ attitudes to patients with a self diagnosis of myalgic encephalomyelitis

Comment in:

GPs’ attitudes to a self diagnosis of myalgic encephalomyelitis. Evidence supports presence of encephalitis. [BMJ. 1995]

GPs’ attitudes to a self diagnosis of myalgic encephalomyelitis. Sufferers continue to be misrepresented. [BMJ. 1995]

 

Interest in the symptom of tiredness has increased with the suggestion of a syndrome of prolonged fatigue caused by infection. The syndrome is referred to as myalgic encephalomyelitis, even though no evidence exists that sufferers have encephalitis or myelitis. Active support organisations encourage self diagnosis 1 and advise how to approach a general practitioner who “doesn’t believe in ME.”2 Problems in doctor-patient relationships may be a factor in persistent disability in fatigue states.3 We therefore used a case vignette method to examine how self diagnosis of myalgic encephalomyelitis could influence general practitioners.4

You can read the full article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2548881/pdf/bmj00581-0036.pdf

 

Source: Scott S, Deary I, Pelosi AJ. General practitioners’ attitudes to patients with a self diagnosis of myalgic encephalomyelitis. BMJ. 1995 Feb 25;310(6978):508. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2548881/

 

Case control study of chronic fatigue in pediatric patients

Abstract:

OBJECTIVE: To determine the demographic characteristics, medical features, psychological profile, and natural history of children with chronic fatigue.

DESIGN: Case control study.

SETTING: Pediatric Infectious Diseases Clinic of Kosair Children’s Hospital, 1990 to 1992.

PARTICIPANTS: Forty-four patients referred for persistent fatigue were evaluated. Twenty patients participated in a psychological study; 20 healthy controls of similar age and gender were recruited from community pediatric practices and 20 matched depressed controls were recruited from university psychiatry services (subjects were treated as groups in the analyses).

MEASURES: Demographic data were obtained for all referred patients. Those with fatigue for at least 2 months and no alternative diagnosis received a detailed history, physical, and battery of laboratory tests (complete blood count, sedimentation rate, chemistry panel, chest X-ray thyroid stimulating hormone, thyroxine, anti-nuclear antibodies, urinalysis, immunoglobulins, and Epstein-Barr virus (EBV), toxoplasma, and cytomegalovirus serologies). Psychological study participants completed the following: background structured interview; Kaufman Brief Intelligence Test; Children’s Depression Inventory; Child Behavior Checklist; Youth Self Report; Diagnostic Interview for Children and Adolescents-Revised; mail-in follow-up survey.

RESULTS: The median age of fatigue patients was 14.3 years; 60% were female, 96% white, and 87% from the mid/upper socioeconomic status (SES). Fatigue patients were demographically similar to 21 patients referred for infectious mononucleosis (IM) but were older than other clinic patients (P < .0001). White race (P = .0568) and mid/upper SES (P = .0403) were over-represented among fatigue patients compared to patients referred for other diagnoses. Of 36 patients meeting criteria for further study, 5 had an IM-like illness including evidence of recent EBV infection. For the remaining 31 patients, clinical and laboratory evaluations were unrevealing. Psychological study subjects reported marked declines in quality-of-life and scored high on measures of internalizing, withdrawal, and social isolation. Nine met diagnostic criteria for depression, although depressive symptoms were not as prominent as those reported by depressed controls. Fatigue subjects scored higher on somatization than both control groups. The follow-up survey indicated symptomatic improvement in most patients.

CONCLUSIONS: Chronic fatigue was a common reason for referral, with over-representation of white children from mid/upper SES. After exclusion of EBV-associated IM, screening laboratory tests were not helpful in establishing specific organic diagnoses. Whereas the natural history was favorable, chronic fatigue resulted in major quality-of-life changes and was associated with significant levels of psychosocial distress.

IMPLICATIONS: Psychological evaluation is warranted in these patients, as some may have treatable psychological conditions. Given the absence of proved medical therapies, psychosocial interventions to improve quality-of-life should be studied.

 

Source: Carter BD, Edwards JF, Kronenberger WG, Michalczyk L, Marshall GS. Case control study of chronic fatigue in pediatric patients. Pediatrics. 1995 Feb;95(2):179-86. http://www.ncbi.nlm.nih.gov/pubmed/7838632

 

The impact of catastrophic beliefs on functioning in chronic fatigue syndrome

Abstract:

This study investigated the association between catastrophic beliefs and disability in the context of Chronic fatigue syndrome (CFS). A sample of 282 CFS sufferers were asked about the consequences of pushing themselves beyond their present physical state. Responses were coded into catastrophic or non-catastrophic categories. While not differing on the length of illness or psychological adjustment, subjects demonstrating catastrophic responses evidenced significantly higher levels of fatigue and were more disabled in terms of their ability to work both in their normal occupation and around the house. Catastrophizers also showed greater disability in terms of their sleep and rest, social communication, and recreational activities. The role of catastrophic beliefs and personal perceptions of CFS in maintaining the illness is discussed.

 

Source: Petrie K, Moss-Morris R, Weinman J. The impact of catastrophic beliefs on functioning in chronic fatigue syndrome. J Psychosom Res. 1995 Jan;39(1):31-7. http://www.ncbi.nlm.nih.gov/pubmed/7760301