The prognosis of different fatigue diagnostic labels: a longitudinal survey

Abstract:

BACKGROUND: Several different diagnostic labels exist for the fatigue syndromes, including chronic fatigue syndrome (CFS), myalgic encephalomyelitis (ME) and postviral fatigue syndrome (PVFS). An allied condition is fibromyalgia. No study has examined prognostic differences across these different labels.

OBJECTIVE: To compare the prognoses of patients labelled with different fatigue syndromes in primary care.

METHODS: We performed a longitudinal survey, using electronic records from the General Practice Research Database. All 18,122 patients diagnosed by their GP with a fatigue syndrome from 1988-2001 with a minimum of one year of records after diagnosis were collated into four groups: CFS, ME, PVFS and fibromyalgia. CFS and ME were combined for the main analysis as no code for CFS was available until 1995. The length of illness was calculated as the interval between the diagnosis and the last recorded fatigue symptom, expressed as days per year, to account for differing lengths of record after diagnosis.

RESULTS: Patients with CFS/ME combined had a worse prognosis (median length of illness 80 days per year; interquartile range 0-242) than fibromyalgia (51; 0-244) or PVFS 0 (0-108), a significant difference, P < 0.001. In a subgroup analysis, ME had a worse prognosis (median length of illness in days per year 106; interquartile range 0-259) than CFS (33; 0-170), P < 0.001, in spite of a better course before diagnosis. Secondary outcome measures were consistent with these results.

CONCLUSION: There were important differences in outcome between the various fatigue labels, with ME having the worst prognosis and PVFS the best. This could be an adverse effect of the label ME itself. Alternatively, patients who are destined to have a worse prognosis may preferentially attract the ME label. Our data support the first interpretation.

 

Source: Hamilton WT, Gallagher AM, Thomas JM, White PD. The prognosis of different fatigue diagnostic labels: a longitudinal survey. Fam Pract. 2005 Aug;22(4):383-8. Epub 2005 Apr 1. http://fampra.oxfordjournals.org/content/22/4/383.long (Full article)

 

Cognitive behaviour therapy for adolescents with chronic fatigue syndrome: data are insufficient and conclusion inappropriate

Comment on: Cognitive behaviour therapy for adolescents with chronic fatigue syndrome: randomised controlled trial. [BMJ. 2005]

 

Editor—I have concerns about the design and interpretation of the study reported by Stulemeijer et al on cognitive behaviour therapy for adolescents with chronic fatigue syndrome.1 The trial arms were not matched for the number of contacts with healthcare professionals. Experience from larger and more carefully controlled randomised interventional trials of patients with chronic fatigue syndrome has clearly shown that short term improvement in symptoms is related directly to the maintenance of regular contacts with healthcare professionals rather than the therapeutic effect of the intervention itself and consequently, the improvement is not sustained once the contact is lost.2

The authors did not offer patients in their waiting list the opportunity to meet therapists regularly for five months but without having cognitive behaviour therapy. Few follow up data on patients in the intervention arm show that the specific treatment benefit was carried forward without regular contacts with the therapists. A cautious approach is essential in inferring direct benefit from cognitive behaviour therapy in the intervention arm (as opposed to short term benefit from close contact with therapists). The level of activity in some of their participants whom the authors considered to be passive remained unclear.

You can read the rest of this comment here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC555921/

 

Source: Chaudhuri A. Cognitive behaviour therapy for adolescents with chronic fatigue syndrome: data are insufficient and conclusion inappropriate. BMJ. 2005 Apr 2;330(7494):789-90; author reply 790. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC555921/ (Full article)

 

Predictors of outcome following treatment for chronic fatigue

Abstract:

We explored the role of baseline characteristics of 105 patients who presented with fatigue in primary care in determining outcome following either graded exercise or cognitive-behavioural therapy. Meeting the criteria for chronic fatigue syndrome was the most powerful predictor of poor outcome and this negative effect was enhanced by greater functional impairment or greater perceived negative consequences, but was not further enhanced by both.

 

Source: Darbishire L, Seed P, Ridsdale L. Predictors of outcome following treatment for chronic fatigue. Br J Psychiatry. 2005 Apr;186:350-1. http://bjp.rcpsych.org/content/186/4/350.long (Full article)

 

Exercise capacity and immune function in male and female patients with chronic fatigue syndrome (CFS)

Abstract:

Hyperactivition of an unwanted cellular cascade by the immune-related protein RNase L has been linked to reduced exercise capacity in persons with chronic fatigue syndrome (CFS). This investigation compares exercise capacities of CFS patients with deregulation of the RNase L pathway and CFS patients with normal regulation, while controlling for potentially confounding gender effects.

Thirty-five male and seventy-one female CFS patients performed graded exercise tests to voluntary exhaustion. Measures of peak VO2, peak heart rate, body mass index, perceived exertion, and respiratory quotient were entered into a two-way factorial analysis with gender and immune status as independent variables. A significant multivariate main effect was found for immune status (p < 0.01), with no gender effect or interaction.

Follow-up analyses identified VO2(peak) as contributing most to the difference. These results implicate abnormal immune activity in the pathology of exercise intolerance in CFS and are consistent with a channelopathy involving oxidative stress and nitric oxide-related toxicity.

 

Source: Snell CR, Vanness JM, Strayer DR, Stevens SR. Exercise capacity and immune function in male and female patients with chronic fatigue syndrome (CFS). In Vivo. 2005 Mar-Apr;19(2):387-90. http://iv.iiarjournals.org/content/19/2/387.long (Full article)

 

Exercise responsive genes measured in peripheral blood of women with chronic fatigue syndrome and matched control subjects

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is defined by debilitating fatigue that is exacerbated by physical or mental exertion. To search for markers of CFS-associated post-exertional fatigue, we measured peripheral blood gene expression profiles of women with CFS and matched controls before and after exercise challenge.

RESULTS: Women with CFS and healthy, age-matched, sedentary controls were exercised on a stationary bicycle at 70% of their predicted maximum workload. Blood was obtained before and after the challenge, total RNA was extracted from mononuclear cells, and signal intensity of the labeled cDNA hybridized to a 3800-gene oligonucleotide microarray was measured. We identified differences in gene expression among and between subject groups before and after exercise challenge and evaluated differences in terms of Gene Ontology categories. Exercise-responsive genes differed between CFS patients and controls. These were in genes classified in chromatin and nucleosome assembly, cytoplasmic vesicles, membrane transport, and G protein-coupled receptor ontologies. Differences in ion transport and ion channel activity were evident at baseline and were exaggerated after exercise, as evidenced by greater numbers of differentially expressed genes in these molecular functions.

CONCLUSION: These results highlight the potential use of an exercise challenge combined with microarray gene expression analysis in identifying gene ontologies associated with CFS.

 

Source: Whistler T, Jones JF, Unger ER, Vernon SD. Exercise responsive genes measured in peripheral blood of women with chronic fatigue syndrome and matched control subjects. BMC Physiol. 2005 Mar 24;5(1):5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1079885/ (Full article)

 

Subjective quality of life in patients with chronic fatigue syndrome

Abstract:

The aim of this study was to (1) assess Subjective Quality of Life (SQOL) of patients with Chronic Fatigue Syndrome (CFS) using a generic concept and to compare the findings with those in groups with mental disorders and healthy subjects, and (2) investigate whether and, if so, to what extent socio-demographic and clinical variables predict SQOL in CFS patients.

Seventy-three patients diagnosed with CFS were randomly selected and interviewed from two specialised clinics. CFS was diagnosed using the Oxford Criteria. SQOL was assessed on the Manchester Short Assessment of Quality of Life (MANSA) and Health-Related Quality of Life (HRQOL) on the Medical Outcome Study Short-Form 36 (MOS) SF-36. A battery of mood and symptom questionnaires, including the Symptom Checklist Questionnaire (SCL-90-R), was administered to assess various aspects of symptomatology as potential predictor variables.

Multiple regression analyses were conducted to identify predictors of SQOL. Overall, SQOL was low in CFS patients and less favourable than in groups with mental disorders and healthy subjects. Satisfaction was particularly low with life as a whole, leisure activities and financial situation. Whilst SQOL was only moderately correlated with HRQOL, the SCL-90-R score, especially SCL-90-R Depression scale score, was the best predictor of SQOL explaining 35% of the variance. HRQOL and generic SQOL appear distinct despite some overlap.

The findings underline that SQOL is significantly disrupted in CFS patients. Depressive symptoms are statistically the strongest ‘predictor’ of SQOL, although the direction of the relationship is not established. These data suggest that treatment of depression associated with CFS, regardless of causation, could help to improve SQOL in CFS patients.

 

Source: Rakib A, White PD, Pinching AJ, Hedge B, Newbery N, Fakhoury WK, Priebe S. Subjective quality of life in patients with chronic fatigue syndrome. Qual Life Res. 2005 Feb;14(1):11-9. http://www.ncbi.nlm.nih.gov/pubmed/15789937

 

The placebo response in the treatment of chronic fatigue syndrome: a systematic review and meta-analysis

Abstract:

OBJECTIVE: The placebo response is conventionally asserted to be high in chronic fatigue syndrome (CFS) because of the latter’s subjective nature and obscure pathogenesis, but no systematic review of placebo responses has been undertaken. We report such a study. Patient expectation is known to be important in the placebo response. It is also known that CFS patients attending specialist clinics often have strong physical attributions regarding causation and hence skepticism about psychological or psychiatric interventions. If so, the placebo response in CFS may be influenced by the type of intervention according to its perceived rationale. We aimed to estimate the summary placebo response in clinical trials of CFS and to determine whether intervention type influences the placebo response in CFS.

METHODS: We searched Medline, Embase, Cochrane Library, PsychInfo, and the references of the identified articles, and contacted experts for controlled trials (randomized or nonrandomized) of any intervention on CFS patients reporting the placebo response as a clinical improvement in physical or general outcomes. Data were extracted from the articles and validity assessment conducted by one reviewer and checked by a second. Meta-analysis and metaregression were performed.

RESULTS: The pooled placebo response was 19.6% (95% confidence interval, 15.4-23.7), lower than predicted and lower than in some other medical conditions. The meta-regression revealed that intervention type significantly contributed to the heterogeneity of placebo response (p = .03).

CONCLUSION: In contrast with the conventional wisdom, the placebo response in CFS is low. Psychological-psychiatric interventions were shown to have a lower placebo response, perhaps linked to patient expectations.

 

Source: Cho HJ, Hotopf M, Wessely S. The placebo response in the treatment of chronic fatigue syndrome: a systematic review and meta-analysis. Psychosom Med. 2005 Mar-Apr;67(2):301-13. http://www.ncbi.nlm.nih.gov/pubmed/15784798

 

A feasibility study comparing two treatment approaches for chronic fatigue syndrome in adolescents

Chronic fatigue syndrome (CFS) involves severe disabling fatigue that affects physical and mental functioning.1 Reported prevalence varies between 0.05% and 2% depending on definitions and methodologies.2 3 There are significant short and long term effects on young people and their families, including long term school non-attendance.4 5 Most reported studies are not randomised, are from a variety of different clinical settings, and show variable outcomes: 5–20% being seriously incapacitated in the longer term, with larger numbers having residual symptoms.2 6–9

You can read the rest of this article here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1720370/pdf/v090p00369.pdf

 

Source: Wright B, Ashby B, Beverley D, Calvert E, Jordan J, Miles J, Russell I, Williams C. A feasibility study comparing two treatment approaches for chronic fatigue syndrome in adolescents. Arch Dis Child. 2005 Apr;90(4):369-72. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1720370/pdf/v090p00369.pdf (Full article)

 

Prevalence of severe fatigue in primary care

Although chronic fatigue in UK adult primary care patients is relatively common,1 there have been no comparative studies in children. Estimates of the prevalence of chronic fatigue syndrome (CFS) or CFS-like illness in children vary widely according to case definition and methodology and range from 2.7/100 0002 to 570/ 100 000,3 although they all suggest that the prevalence is lower than among adults.1

You can read the rest of this article here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1720362/pdf/v090p00367.pdf

 

Source: Haines LC, Saidi G, Cooke RW. Prevalence of severe fatigue in primary care. Arch Dis Child. 2005 Apr;90(4):367-8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1720362/pdf/v090p00367.pdf (Full article)

 

Prevalence of atopy in chronic fatigue syndrome

Abstract:

BACKGROUND: Several hypotheses have been postulated to explain the etiopathogenesis of chronic fatigue syndrome (CFS). Among these, immunologic dysfunction has been proposed. Up to 30 % of these patients have a history of allergic disease. The aim of this study was to investigate whether allergic sensitization is higher in patients with CFS than in the general population.

METHODS: Twenty-five patients with CFS and 20 controls were evaluated. A clinical history for allergy was taken and immediate hypersensitivity tests were performed.

RESULTS: Twelve patients (48 %) and eight controls (40 %) had a family history of atopy. Personal histories of atopy were as follows: rhinoconjunctivitis: 12 patients (48 %), seven controls (35 %); asthma: five patients (20 %), two controls (10 %); food allergy: three patients (12 %); atopic dermatitis: two patients; contact dermatitis: two patients. No statistically significant differences were found between the groups in any of the variables (p > 0.05). In the CSF group, 3.4 % (15/441) of the inhalant prick tests were positive, and in the control group 3.8 % (16/420) were positive. None of the tests for hypersensitivity to food or latex were positive.

CONCLUSIONS: In our study atopy was not more prevalent in patients with CFS than in healthy controls, although the CSF group tended to report more respiratory symptoms and drug allergies.

 

Source: Ferré Ybarz L, Cardona Dahl V, Cadahía García A, Ruiz E, Vázquez A, Fernández de Sevilla T, Alegre Martín J. Prevalence of atopy in chronic fatigue syndrome. Allergol Immunopathol (Madr). 2005 Jan-Feb;33(1):42-7. [Article in Spanish] http://www.ncbi.nlm.nih.gov/pubmed/15777523