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Twisk in reactie op

artikel Meeus en anderen:

de essentie van "ME"

is post-exertoniele "malaise"








Naar aanleiding van een recent verschenen studie van Mira Meeus en collega's

heb ik een ingezonden brief gestuurd naar de redacteur van Clinical Rheumatology (zie onder).


Meeus, Nijs en anderen stellen op basis van subjectieve en objectieve criteria vast dat ME/CVS

gepaard gaat met grote beperkingen, cognitieve klachten en afgenomen spierkracht-/herstel.


Ook stellen zij artsen zich niet al te druk druk hoeven te maken over dat diagnosecriteria (1, 2 en 3).

Die "aanbeveling" doen zij o.m. op basis van het feit dat de symptomen en mate van invaliditeit

bij 10 CVS-patiŽnten die niet aan de Ramsay-criteria voldeden niet afweken niet noemenswaardig

afweken van die van de overige 38 CVS-patiŽnten die wel aan de Ramsay-criteria voldeden.


Het belangrijkste argument tegen de aanbeveling dat diagnosecriteria er nauwelijks toe doen

is het feit dat er geen vergelijking gemaakt is tussen "CVS"-patiŽnten mťt post-exertional "malaise" (objectief vastgesteld) en "CVS"-patiŽnten zonder dit karakteristieke symptoom van ME.

Alhoewel de brief door de ene reviewer als ter zake doend en relevant werd beoordeeld,

was de andere reviewer van mening dat de "CVS"-criteria welllicht zelfs te strikt zijn en

dat het bewijs van de afwijkingen (in subgroepen) (referenties: zie onder) niet echt geleverd is.


Op grond van de beoordeling van die laatste reviewer werd de brief voor publicatie afgewezen.


En zo draaien we nog jaren en jaren in cirkeltjes rond...






What is in a name?

Post-exertional "malaise" the essence of ME (Myalgic Encephalomyelitis).


Twisk, FNM.






The accuracy and relevance of the diagnostic criteria for

Myalgic Encephalomyelitis (ME) and/or chronic fatigue syndrome (CFS)

are subject of debate.


A recent study established severe impairment in CFS,

both objectively and subjectively.


Based upon their comparison of

the outcomes of subjective and objective measures of symptom burden

in those only meeting the CFS criteria and

those also fulfilling the original criteria for ME or the 2003 Canadian criteria,

the authors conclude that

the diagnostic criteria are of little relevance to clinicians.


Despite its great relevance,

this study fails to address a crucial issue:

a subdivision of patients with post-exertional "malaise":

a prolonged increase of ďfatigueĒ, cognitive deficits, pain etc.

after minimal (physical or mental) exertion,

labelled ME patients,

and those without,

labelled CFS patients.


There is evidence that

ME and CFS patients

are distinct symptomatological and immunological patient subgroups.


This distinction and an accurate diagnosis,

based upon objective measures,

have important implications for

the effect of proposed effective therapies,

e.g. graded exercise therapy.





Myalgic Encephalomyelitis, chronic fatigue syndrome,

assessment, post-exertional malaise, exercise






A recent study (1) provides a wealth of data on

the level of impairment in

Myalgic Encephalomyelitis (ME) / chronic fatigue syndrome (CFS),

both assessed subjectively as objectively.


Based upon the outcomes of subjective and objective measures

in those only meeting the CFS criteria and

those also fulfilling the criteria for ME,

as defined by Ramsay et al., or the 2003 Canadian criteria,

the authors conclude that

'[I]t seems that clinicians should not bother too much about the diagnostic criteria,

as long as either the 1994 CDC criteria [for CFS] or

the Canadian criteria [for ME/CFS] are used' (1).


While the study is indisputably of great relevance,

it fails to address a crucial issue (2):

the distinction between patients with post-exertional malaise,

a prolonged increase of ďfatigueĒ, cognitive deficits, pain etc.

after minimal exertion, and

patients without this phenomenon (3).


As Meeus et al. (1) did with other symptoms,

e.g. cognitive deficits, muscle power and recovery,

the most crucial feature of ME (2), post-exertional malaise,

should be assessed objectively, e.g. by

a) by using repeated exercise tests (4,5);

b) comparing scores on (specific) cognitive tests before and after a single exercise test (6,7);

c) assessing cognitive test scores at various degrees of orthostasis (8,9); and

d) comparing the scores of two cognitive tests with 4-24h rest in-between.


Post-exertional "malaise", e.g. as indicated by

a decline in oxygen uptake at the anaerobic threshold and/or at peak exercise (5),

is present or not.


Subjective measures, e.g. visual analog scales scores (1),

are inadequate,

since healthy controls also report to experience post-exertional "malaise" (10).


Post-exertional "malaise" is reflected by distinctive immunological abnormalities (11).


A recent study established unique immunological abnormalities

in patients meeting the ICC criteria for ME (12),

in which post-exertional "malaise" is obligatory, and

patients only fulfilling the criteria for CFS, and

highly significant correlations

between the physical status and immune parameters in ICC patients (13).


Another study (14) observed neuroinflammation

in widespread brain areas in ME patients (12),

which was associated with the severity of neuropsychological symptoms.


Johnston et al. (15) found that

patients meeting the ICC criteria for ME

reported significantly lower scores for

physical functioning, physical role, bodily pain, and social functioning

than those that only meeting the CFS criteria.


Since there is debate about the name (1),

the diagnostic criteria, and the distinction between ME and CFS (2),

the lack of a comparison of

patients with post-exertional malaise (11), established objectively,

with patients without this anomaly is a missed opportunity.



'the lack of power to compare

those fulfilling the [original] ME criteria and those who did not

prohibits drawing firm conclusions regarding these criteria' (1) and

the fact that there were

no comparisons made

between the clinical picture of

patients with and without post-exertional malaise and

other potentially essential criteria of ME (12),

the conclusion that

'clinicians should not bother too much about the diagnostic criteria' (1)

is very premature at the least.


As noted, post-exertional "malaise" is obligatory for the diagnosis ME

according to the recently published International Consensus Criteria for ME (12).


Whether these criteria are too restrictive

with regard to other essential symptoms (10)

remains to be elucidated.


In conclusion,

without investigating

the differences in the clinical picture of

(ME) patients with post-exertional "malaise", and

CFS patients without this symptom objectively and

with sufficient statistical power,

it is preliminary to conclude that

diagnostic criteria have little relevance.


It seems likely that

exercise therapies will intensify the symptoms

in patients with long-lasting post-exertional "malaise": ME patients.


Therefore an accurate diagnosis

using objective measures is crucial (2).





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