Tag: comment

Exercise responses in the chronic fatigue syndrome. Objective assessment of study is difficult without knowledge of data

Comment on: Exercise responses and psychiatric disorder in chronic fatigue syndrome. [BMJ. 1995]

 

EDITOR,-In their study of exercise responses and psychiatric disorder in the chronic fatigue syndrome Russell J M Lane and colleagues claim to have detected abnormal lactate responses to subanaerobic threshold exercise in 31 of 96 patients. As no data are offered to support this statement, however, objective assessment of the validity of their findings is difficult.

The authors’ definition of an abnormal response is “lactate concentrations exceeding the upper 99% reference limit for normal control subjects at two or more time points.” However, only three samples were taken (before, immediately after, and 30 minutes after exercise), and a raised lactate concentration in the sample obtained before exercise began cannot be described as an abnormal response to exercise. Neither the method used to measure lactate nor its precision is given; assessment of the importance of the “abnormal” lactate concentrations could not be guessed at without this information, even if the authors had given details of the patients’ concentrations.

You can read the full comment along with the authors’ reply here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2551191/pdf/bmj00618-0070a.pdf

 

Source: Hutchison AS. Exercise responses in the chronic fatigue syndrome. Objective assessment of study is difficult without knowledge of data. BMJ. 1995 Nov 11;311(7015):1304. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2551191/pdf/bmj00618-0070a.pdf

 

Illness behaviour in the chronic fatigue syndrome and multiple sclerosis. Disentangling common characteristics is not so easy

Comment on: “Abnormal” illness behaviour in chronic fatigue syndrome and multiple sclerosis. [BMJ. 1995]

 

EDITOR,-Over the past few years I have seen a growing number of patients with the chronic fatigue syndrome who have been told by psychiatrists and psychologists that abnormal illness behaviour and psychosocial factors are the main factors perpetuating their disability. Few patients have accepted or believed this explanation; neither have I. The ME Association now has evidence that the fashionable theory of abnormal illness behaviour linked to somatisation is being used by several agencies as a convenient excuse for turning down applications for financial benefits or for putting pressure on vulnerable patients to undergo speculative “rehabilitation” programmes, which they may be reluctant to participate in.

Although Peter Trigwell and colleagues conclude that patients with the chronic fatigue syndrome and multiple sclerosis have virtually identical patterns of illness behaviour without any form of shared aetiology, their study suggests that the two conditions may have more in common than just central fatigue and uncertainty about long term prognosis.’ When DeLuca et al examined patients with the chronic fatigue syndrome, patients with multiple sclerosis, and healthy controls using a paced auditory serial addition test (a method of assessing processing of complex auditory information) they found that both groups of patients scored significantly below the controls, indicating similar difficulties with tasks that require simultaneous processing of cognitive information.2

You can read the full comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2551397/pdf/bmj00615-0064a.pdf

 

Source: Shepherd C. Illness behaviour in the chronic fatigue syndrome and multiple sclerosis. Disentangling common characteristics is not so easy. BMJ. 1995 Oct 21;311(7012):1093. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2551397/pdf/bmj00615-0064a.pdf

 

Illness behaviour in the chronic fatigue syndrome and multiple sclerosis. Choice of multiple sclerosis as comparison condition was inappropriate

Comment on: “Abnormal” illness behaviour in chronic fatigue syndrome and multiple sclerosis. [BMJ. 1995]

 

EDITOR,-Peter Trigwell and colleagues compared patients with the chronic fatigue syndrome with patients with multiple sclerosis and report similar responses on Pilowsky’s illness behaviour questionnaire.’ There is accumulating evidence that the chronic fatigue syndrome is a functional disorder, with psychological, social, and physical factors implicated in its cause, whereas in multiple sclerosis the primary cause is physical. Wood et al compared patients with the chronic fatigue syndrome with patients with various muscle diseases and found a threefold increase in psychiatric diagnoses in the group with the chronic fatigue syndrome.2 Wessely et al describe an important prospective cohort study and conclude that common infections play little part in causing the chronic fatigue syndrome but that both previous psychological disorder and previous fatigue are associated with its development.3

We agree with Trigwell and colleagues that illness behaviour is highly relevant to the chronic fatigue syndrome, but we share their reservations about the particular method of assessing this. We also suggest that the choice of multiple sclerosis as a comparison condition was inappropriate. Multiple sclerosis, in contrast to muscle diseases, follows a relapsing and remitting course, often manifests sensory (subjective) rather than motor (objective) signs, and might therefore lead to illness behaviour that is abnormal, albeit for different reasons from those that might apply in the chronic fatigue syndrome.

You can read the full comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2551396/pdf/bmj00615-0063c.pdf

 

Source: Campion PD, Dowrick CF, Edwards RH. Illness behaviour in the chronic fatigue syndrome and multiple sclerosis. Choice of multiple sclerosis as comparison condition was inappropriate. BMJ. 1995 Oct 21;311(7012):1092-3. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2551396/pdf/bmj00615-0063c.pdf

Patients with a self diagnosis of myalgic encephalomyelitis

Comment on: Patients with a self diagnosis of myalgic encephalomyelitis. [BMJ. 1995]

 

EDITOR,-S J Hurel and colleagues should have checked their facts more thoroughly before making such a generalised attack on the content of literature produced by the two support groups for patients with myalgic encephalomyelitis (ME).

The ME Association does not believe that candida albicans is involved in the pathogenesis of the condition. Our booklet Guidelines for the Care of Patients states that “no reliable scientific evidence has ever been published to support such a link” and that “consequently, anti-candida regimes involving highly restricted diets, probiotics and antifungal drugs cannot be recommended.”2 Equally, we repeatedly warn our members about the serious dangers of colonic cleansing (particularly in relation to the risk of unhygienic operators transferring gastrointestinal pathogens) and advise extreme caution when consulting herbalists or buying over the counter herbal remedies. If we really were producing literature that contained pseudoscientific nonsense and advocated dubious forms of alternative therapy I doubt whether the Department of Health would be providing funding to expand the work of our information department.

Had the authors checked with our booklet they would have found that we are not in favour of self diagnosis and strongly recommend consideration of nearly 50 physical and psychological conditions that can present with chronic fatigue as the principal clinical feature. In this context pituitary tumours are specifically mentioned as we are aware of at least two other cases similar to that reported by Hurel and colleagues in which misdiagnosis occurred. Furthermore, our literature emphasises that “significant or progressive weight loss is not a normal feature of ME, and where it occurs alternative explanations (eg hormonal) should always be excluded.”

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2550999/pdf/bmj00614-0065a.pdf

 

Source: Shepherd C. Patients with a self diagnosis of myalgic encephalomyelitis. BMJ. 1995 Oct 14;311(7011):1021. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2550999/pdf/bmj00614-0065a.pdf (Full comment)

 

Patients with a self diagnosis of myalgic encephalomyelitis

Comment in: Patients with a self diagnosis of myalgic encephalomyelitis. [BMJ. 1995]

 

EDITOR,-Myalgic encephalomyelitis is most commonly related to an underlying psychological or psychiatric disturbance.’2 Shonagh Scott and colleagues report that when general practitioners deal with symptoms consistent with those of myalgic encephalomyelitis their attitude is likely to be influenced by the patient’s perception, expectations, and social class.’ It is not uncommon for patients to diagnose myalgic encephalomyelitis themselves before they seek a consultation; this can lead to disruption of the doctor-patient relationship, unsatisfactory consultations, and possibly failure to diagnose any underlying pathological process. We report on a patient with a self diagnosis of myalgic encephalomyelitis in whom hypopituitarism was diagnosed only after a protracted period

You can read the full comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2550388/pdf/bmj00603-0061a.pdf

Comment on:

Population based study of fatigue and psychological distress. [BMJ. 1994]

Professional and popular views of chronic fatigue syndrome. [BMJ. 1994]

 

Source: Hurel SJ, Abuiasha B, Baylis PH, Harris PE. Patients with a self diagnosis of myalgic encephalomyelitis. BMJ. 1995 Jul 29;311(7000):329. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2550388/pdf/bmj00603-0061a.pdf (Full comment)

 

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/

 

GPs’ attitudes to a self diagnosis of myalgic encephalomyelitis. Sufferers continue to be misrepresented

Comment on: General practitioners’ attitudes to patients with a self diagnosis of myalgic encephalomyelitis. [BMJ. 1995]

 

EDITOR,-Shonagh Scott and colleagues’ paper on general practitioners’ attitudes to self diagnosed myalgic encephalomyelitis illustrates, if nothing else, the continuing misrepresentation of this illness and those who suffer from it.’ Contrary to the authors’ claims, Action for ME has never encouraged self diagnosis, and nor have the other “active support organisations” in Britain. Moreover, we have never advocated that patients should make unreasonable demands on their general practitioners.

Despite what Scott and colleagues imply, it is not just patients who recognise the existence of myalgic encephalomyelitis but also the World Health Organisation (the disease appears in the International Classification of Diseases (10th revision)), several handbooks, and many doctors. Indeed, positive attitudes to fatigue syndromes such as myalgic encephalomyelitis have been noted in several studies in the past few years. For instance, Ho-Yen and McNamara surveyed 178 general practitioners in Scotland and found that 71% accepted the existence of the disorder.2 In New Zealand the figure was 90%.3

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2549698/pdf/bmj00593-0058a.pdf

 

Source: Arber M. GPs’ attitudes to a self diagnosis of myalgic encephalomyelitis. Sufferers continue to be misrepresented. BMJ. 1995 May 20;310(6990):1330. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2549698/

 

Chronic fatigue syndrome and fibromyalgia

Comment on: Population study of tender point counts and pain as evidence of fibromyalgia. [BMJ. 1994]

 

EDITOR,-The relation between muscle pain, tender points, the chronic fatigue syndrome, and fibromyalgia are complex, and simplistic answers are inappropriate. In their paper Peter Croft and colleagues extrapolate their results to make two statements that I believe to be incorrect.’

My conclusions are based on 100 consecutive patients seen at Raigmore Hospital NHS Trust, who fulfilled precise definitions of the chronic fatigue syndrome 2 or fibromyalgia.3 The importance of this definition of the syndrome is that it has the same three month cut off for length of illness as fibromyalgia.3 Of the 100 patients, 99 (74 women, 25 men) had the chronic fatigue syndrome and one (a woman) had fibromyalgia. Of the patients with the chronic fatigue syndrome, 63 had muscle pain and 28 had tender points on examination, 23 had both, and five had no muscle pain but tender points. These results do not support the authors’ statement that the reason why fibromyalgia is not more common in Britain has been the acceptability of the chronic fatigue syndrome as an alternative diagnosis.

The authors also say that it is “inappropriate to define an entity as fibromyalgia.” As a clinical virologist, I strongly disagree with this as the distribution and number of tender points in fibromyalgia are different from those in the chronic fatigue syndrome, and the management of the two conditions is different.4 Patients with the syndrome should be advised not to increase their activities gradually until they feel 80% of normal,5 whereas patients with fibromyalgia may benefit from a regimen of increasing activity.4

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2541601/pdf/bmj00468-0067b.pdf

 

Source: Ho-Yen DO. BMJ. Chronic fatigue syndrome and fibromyalgia. 1994 Dec 3;309(6967):1515. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2541601/

 

Single fibre EMG studies in chronic fatigue syndrome: a reappraisal

Comment on: Single fibre EMG studies in chronic fatigue syndrome: a reappraisal. [J Neurol Neurosurg Psychiatry. 1994]

 

We were interested in the short report from Roberts and Byrne concerning single fibre EMG studies in chronic fatigue syndrome. They concluded that there was no evidence of abnormality at the terminal axon, neuromuscular junction, or muscle membrane in patients with chronic fatigue syndrome-a finding that concurs with our own of essentially normal jitter in 34 of 35 patients with chronic unexplained fatigue. We did detect some evidence of raised fibre density in a small subgroup of patients with pronounced myalgia who also had mild abnormalities on muscle biopsy.

Raised fibre density is usually a result of collateral sprouting after reinnervation, but can also be due to fibre splitting as can occur in some myopathic states. Therefore we believe that fibre density estimation performed in addition to jitter measurement adds considerably to the information obtained from single fibre EMG studies.

You can read the full comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1073160/pdf/jnnpsyc00039-0137a.pdf

 

Source: Connolly S, Fowler CJ. Single fibre EMG studies in chronic fatigue syndrome: a reappraisal. J Neurol Neurosurg Psychiatry. 1994 Sep;57(9):1157. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1073160/

 

Chronic fatigue syndrome and myalgic encephalomyelitis

Comment on:

Chronic fatigue syndrome. Distinguish between syndromes… [BMJ. 1994]

Chronic fatigue syndrome. Role of psychological factors overemphasised. [BMJ. 1994]

 

Editor,-Our recent editorial on the chronic fatigue syndrome and myalgic encephalomyelitis prompted considerable correspondence,’ which raised issues of case definition, clinical management, and attitudes towards people with psychiatric illnesses. Sadly, many of our critics show that the editor of the BMJ is wrong to state in the “editor’s choice” in the issue of 14 May that “only the naivest medical students think that diseases have some independent, objective reality.” Medical students show greater intellectual sophistication in tackling the classification of ill defined illnesses than many patients and doctors-and particularly medical practitioners with self diagnosed myalgic encephalomyelitis.

Case definition-Ellen M Goudsmit’ and Nick Anderson’ assert that research criteria for the chronic fatigue syndrome fail to distinguish myalgic encephalomyelitis and exaggerate psychiatric associations. The best replicated research finding, however, is that patients suffer substantial emotional morbidity, whether the chronic fatigue syndrome is defined by British or, as patient groups prefer, Australian or American criteria. All three sets of criteria can be used to identify cases on a continuum of fatigue, which includes myalgic encephalomyelitis. We did not cite DO Ho-Yen’s prevalence study as it used an idiosyncratic definition of cases of the ‘chronic fatigue syndrome and surveyed doctors’ diagnoses rather than patients.

You can read the full comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2540769/pdf/bmj00450-0067b.pdf

 

Source: Lawrie SM, Pelosi AJ. Chronic fatigue syndrome and myalgic encephalomyelitis. BMJ. 1994 Jul 23;309(6949):275. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2540769/