Artikel Nijmegen januari 2005:

Maja Stulemeijer, Lieke W A M de Jong, Theo J W Fiselier, Sigrid W B Hoogveld, and Gijs Bleijenberg

Cognitive behaviour therapy for adolescents with chronic fatigue syndrome:

randomised controlled trial

BMJ 2005; 330: 14

Full text at: http://bmj.bmjjournals.com/cgi/content/full/330/7481/14

Reaktie Chaudhuri januari 2005:

http://bmj.bmjjournals.com/cgi/eletters/330/7481/14#91025

General conclusion: insufficient data, inappropriate conclusion

 

3 January 2005

Abhijit Chaudhuri,
Senior Lecturer in Clinical Neurosciences
University of Glasgow



I have a few concerns regarding the design and interpretation of this published trial (1).

First, the trial arms were not matched for the number of contacts with the health care 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 are directly related to the maintenance of regular contacts with the health care professionals rather than due to 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 (CBT).

In addition, there are no follow-up data regarding patients in the intervention arm beyond five months to show that the specific treatment benefit was carried forward in the absence of regular contacts with the therapists.

Taken together, one has to be extremely cautious in inferring direct benefit from CBT in the intervention arm (as opposed to short-term benefit from close contact with therapists) and such a claim would only reflect uncritical belief in the efficacy of CBT.

Second, the authors indicated that a proportion of their patients were "passive", i.e., adolescents who spend "most time lying down and go out infrequently. most do not attend school at all" (p2, intervention).

The baseline characteristics show that all participants were attending school - either full time or part time (Table 1) and yet nearly a third of patients in the intervention arm were considered to be "passive" by the authors.
I am not sure if these data are compatible with their own definition of passivity (1). May I ask what were the outcome results of subgroup analysis in the so-called "active" and "passive patients?

Third, the results (Table 2) did not show how many adolescents in each arm returned to full-time schooling, clearly a more meaningful and simpler index of response to therapy.

Fourth, it was suggested that the intervention (CBT) was effective by challenging patients' belief that activity would
aggravate symptoms (p2, "intervention" and p5,"what this study adds").

If it is true, then I am afraid the authors challenged a scientific fact because epidemiological data confirm that fatigue made worse by exercise is a characteristic feature of adolescents at risk of chronic fatigue syndrome (3).

Encouraging activity in disabled patients is entirely different from challenging an accepted feature of the disease: e.g., when a patient with hemiparesis is encouraged to walk, the existence of weakness due to a stroke is not challenged.

Finally, the trial recruited relatively small number of patients and given a high drop-out rate (nearly 20%) of the participants in the intervention arm, there is a possibility of Type 2 error.

In conclusion, the study does not have the strength to conclude that "CBT is an effective treatment for chronic fatigue syndrome in adolescents"(1).

Amendments regarding the conclusion and the rhetorical summary point of this paper are to be expected from the authors and/or the editors. Failure to do so would perpetuate the view that the BMJ has a selective bias towards research that supports a psychological view of chronic fatigue syndrome irrespective of the quality of the presented material.


References:

1. Stulemeijer M, de Jong LWAM, Fiselier TJW, Hoogveld SWB, Bleijenbrg G. Cognitive behaviour therapy for adolescents with chronic fatigue syndrome: randomised controlled trial. BMJ 2005; 330: 14-18.

2. Blacker CV, Greenwood DT, Wesnes KA, et al. Effect of galantamine hydrobromide in chronic fatigue syndrome: a randomized controlled trial. JAMA 2004; 292: 1195-204.

3. Mears CJ, Taylor RR, Jordan KM, et al. Sociodemographic and symptom correlates of fatigue in an adolescent primary care sample. J Adolesc Health 2004; 35: 528e.21-6.

Competing interests: None declared