Re: Occupational Aspects of the Management of Chronic Fatigue Syndrome: a National Guideline.
Ross et al (2004) review mentioned on page 14:
Employment outcomes
A preliminary literature search showed that, although there is a considerable body of research on CFS, few studies have looked at employment outcomes. During the first GDG meeting, a paper specifically focussing on work outcomes was identified: “Disability and chronic fatigue syndrome – a focus on function” by SD Ross et al. [48]. This paper summarises a systematic review of studies published in English from 1 January 1988 to 15 November 2001. Interventional and observational studies of adults with CFS were eligible for inclusion in the Guideline Development Group’s evidence review if they reported measures of disability and employment. This identified 3,840 studies, of which 37 reported employment status and some measure of mental or physical impairment associated with disability. Most patients with CFS in these studies were unemployed. In 22 studies, the employment status of controls was also available. Only depression seemed to be associated with unemployment in patients with CFS. No other measurable impairment seemed to be consistently associated with disability or work outcomes. Only CBT, rehabilitation, and exercise therapy interventions were associated with restoring the ability to work. No specific patient characteristics were identified as best predictors of positive employment outcomes. The Ross paper concluded that for questions of disability and employment in CFS, the limitations inherent in the current literature are extensive.
Last year I
wrote harshly about using this to support CBT/GET. "Associated" with restoring the ability to work does not mean actually restoring said ability. Basically, three of the four studies had uncontrolled comparisons, and the employment data on the remaining study was based on only 2 people.
Then the national guidelines explores the evidence for itself. Page 19 has the method for selection of papers for critical appraisal. Page 21 has the grading of reviewed evidence. Page 22 has the limitations of the literature review.
Grade A: At least one meta-analysis, systematic review or RCT rated as 1++, and directly applicable to the target population; or A systematic review of RCTs or a body of evidence consisting principally of studies rated as 1+, directly applicable to the target population, and demonstrating overall consistency of results.
Grade B: A body of evidence including studies rated as 2++, directly applicable to the target population, and demonstrating overall consistency of results; or Extrapolated evidence from studies rated as 1++ or 1+.
[etc C and D]
Page 25 has "4. Treatments for CFS that have been shown to improve work outcomes."
Evidence for CBT ("A Grade")
Butler et al. 1991 [40], Deale et al. 1997 [22], Deale et al. 2001 [23].
22. Deale A, Chalder T, Marks I, Wessely S. Cognitive behavior therapy for Chronic Fatigue Syndrome: a randomized controlled trial. American Journal of Psychiatry 1997, 154(3)408–414.
http://ajp.psychiatryonline.org/data/Journals/AJP/3674/408.pdf
Deal et al 1997: Oxford or CDC was used. Table 1 seems to suggest similar levels of unemployment between groups. On quick glance I cannot find mention of employment outcomes. According to the national guidelines:
The study looked at 10 different outcome measures, one of which was the Work and Social Adjustment Scale (WASAS). This scale measures impairment in work, home management, social activities and private leisure. Impairments are measured on a scale of 0–8. 8 represents maximum impairment. Pre-treatment mean WASAS was 6.0 for the 30 CBT patients and 6.1 for the 30 relaxation patients. At 6 months after treatment, mean WASAS was 3.3 for the CBT group and 5.4 for the relaxation group. At six months follow-up, 70% of those who had completed CBT achieved substantial improvement in physical functioning compared with 19% of the relaxation group.
In other words it appears that the WASAS is being confused with employment outcomes.
23. Deale A, Husain K, Chalder T, Wessely S. Long-term outcome of cognitive behavior therapy versus relaxation therapy for Chronic Fatigue Syndrome: a 5-year follow-up study. American Journal of Psychiatry 2001, 158(12)2038–2042.
http://psychiatryonline.org/data/Journals/AJP/3731/2038.pdf
Deale et al 2001: Similar proportions of patients were employed, but patients in the cognitive behavior therapy group worked significantly more mean hours per week : 35.57(8.11) hours vs 24.00 (4.97) hours, p<0.04.
I do not recall all the criticisms for this study but I remember being somewhat surprised when first hearing about them because I did not realize it was that bad. FWIW, this is the only study in the national guidelines which actually has relevant evidence for employment outcomes, and the much larger and better conducted PACE Trial (which showed no improvements in employment outcomes) trumps it anyway.
Interesting quote:
"Predetermined criteria for 'complete recovery' required that patients no longer met chronic fatigue syndrome criteria, were employed full-time, and scored less than 4 on the Fatigue Questionnaire and more than 83 on the Medical Outcomes Study Short-Form General Health Survey physical functioning scale."
40. Butler S, Chalder T, Ron M, Wessely S. Cognitive behavioral therapy in chronic fatigue syndrome. Journal of Neurology, Neurosurgery and Psychiatry 1991, 54:153–158.
http://jnnp.bmj.com/content/54/2/153.full.pdf
Butler et al 1991: Was an
uncontrolled pilot study, (it was rated 2+ which is "Well-conducted case-control or cohort studies with a low risk of confounding, bias, or chance and a moderate probability that the relationship is causal.")
Evidence for GET ("B Grade")
"Prins and couper 1998 [27], and White 1997 Fulcher [32]"
The citation here is somewhat confusing. There is no "Prins and couper 1998". The only mention of Couper is a Cochrane review on CBT not GET. Reference 27 is a CBT study too:
27. Prins JB, Bleijenberg G, Bazelmans E, Elving LD, De Boo TM, Severens JL, Van Der Wilt GJ, Spinhoven P, Van Der Meer JWM. Cognitive behaviour therapy for chronic fatigue syndrome: a multicentre randomised controlled trial. Lancet 2001, 357:841–847.
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(00)04198-2/abstract
"Patients were eligible for the study if they met the US Centers for Disease Control and Prevention criteria for CFS,[1] with the exception of the criterion requiring four of eight additional symptoms to be present."
In other words,
not a study about CFS.
32. Fulcher KY, White PD. Randomised controlled trial of graded exercise in patients with the chronic fatigue syndrome. British Medical Journal 1997, 314:1647–1652.
www.ncbi.nlm.nih.gov/pmc/articles/pmid/9180065/
Fulcher & White 1997: The guidelines graded this as "1+ Well-conducted meta-analyses, systematic reviews of RCTs or RCTs with a low risk of bias." and stated that
"Patients were followed up by questionnaire approximately one year after supervised treatment stopped. 66% of patients who completed exercise treatment were working or studying at least part-time, compared with 39% of all 66 patients before treatment (95% confidence interval of difference 9% to 44%)."
However, AFAIK the comparison of improved occupational status was
uncontrolled at 12 month follow-up because it was a crossover study which did not account for dropouts or compare with the controls that only did the flexibility program instead of the exercise program The authors acknowledge this weakness but then dismiss it by claiming that spontaneous improvement was an unlikely explanation because it didn't occur in a "similar sample" in another study. The sparse details are on p1651. Table 6 of Ross et el points out that follow-up figures are "based on the number of patients enrolled" and at 15 month follow-up from baseline the rate of employment went from 39% to 47% (no control group).
The evidence has never been strong and is now clearly overshadowed by the PACE Trial.
In fact, the only questionnaire outcome measurement where the was a (barely) statistical signficance at 5 years was self-rating of improvement. And if you take into account the 12% of known misdiagnosed CBT patients (who probably had a full recovery due to getting appropriate treatment), there's probably no statistical significance in any of the 5 year results.
