The PACE trials: a £6 million failure

There is nothing complicated about the PACE trials – or at least, there should not have been. Patients were selected to participate in a trial of cognitive behaviour therapy targeted to their “inappropriate illness beliefs” and a course of “graded exercise therapy” to get them back in shape – together this is called CBT/GET and has been proclaimed as the “best” treatment for ME and CFS by the governments of the UK, the US, among others, for two decades now.  [For an excellent critique of the PACE trial, see  David Tuller's "Trial by Error" .]

These treatments are controversial, to say the least. The main reason is that the entire programme of “CBT/GET” with regards to ME and CFS is based on the assertion that the patients’ physical symptoms have no medical explanation – in insurance (and now medical) parlance, these patients all have “MUS”s (Medically Unexplained Symptoms).

But there are numerous studies that DO offer a medical, or physiological, explanation for the symptoms. Most specifically, research has shown that high-functioning patients who fit the Canadian Consensus Criteria for ME/CFS (2003) do perform roughly the same as deconditioned controls on Cardio-Pulmonary Exercise Testing (CPET)  – but on a  SECOND day of testing, while the deconditioned controls perform the same as they did the day before, the patients’ scores drop by as much as one-half. (See, for example, Discriminative Validity of Metabolic and Workload Measurements to Identify Individuals With Chronic Fatigue Syndrome, Christopher R. Snell, Staci R. Stevens, Todd E. Davenport, and J. Mark Van Ness, Physical Therapy (June 2013).

The CPET has long been used in cardiology – and athletics – and is highly regarded as objective. It can’t be gamed. The tester puts a mask over the patients nose and mouth (or over the mouth and clamps the nose shut) so that the air going into and out of the patients’ lungs is measured by a machine while the patient rides a stationary bicycle or walks on a treadmill that gets progressively more difficult. When the patient reaches maximal cardiac effort [a pulse of (200-age) x .8], the machine records the amount of oxygen intake and carbon dioxide release – that is, it measures how much oxygen the patient inputs and how much carbon dioxide has been produced.

CPET testing of patients with ME or CFS – which has now been replicated on three continents by numerous researchers (and is into second-order studies where the patients’ blood is tested for other characteristics before, during, and after testing) has effectively demonstrated that what patients have been saying for years – and what has been recognized by the non-psychiatric school of thought regarding the disease – is both profound and measurable – patients suffer from what is called in the literature “post-exertional malaise” or post-exertional worsening of symptoms.  

This symptom is considered so profound, and so important, that the recent Report on ME/CFS from the Institute of Medicine at the US National Academies of Sciences concluded it should be a requirement for the definition of the disease.

Now, imagine a patient for whom a defining symptom is the inability to maintain the same level of exercise two days in a row. Imagine a treatment where the patient is told to (1) increase exercise daily, and (2) ignore how it makes them feel. These patients end up operating in constant anaerobic metabolism, which is dangerous for trained athletes – certainly it is dangerous for patients.

That brings us to my own principle frustration with this literature. The psychiatric literature on the disease known as ME and/or CFS does not reference the great body of literature on physical abnormalities found in the disease. Those who know nothing of these diseases who read this psychiatric literature won’t know about post-exertional “malaise” (or worsening of symptoms); won’t know about significant cognitive dysfunction and sleep abnormalities; ataxia, gait abnormalities, muscle pain; and – above all – won’t know that one-fourth of patients are either bedridden or housebound.

Here, then, is the major source of the division between QMUL/KCL and the rest of the ME/CFS community.  It has nothing to do with how patients feel about psychiatrists or psychiatric diagnosis.  Rather, the QMUL/KCL world admits to no evidence of physical abnormalities in patients with this disease – an assertion I do not believe they are entitled to make. Certainly readers should have the opportunity to choose for themselves; a full and objective bibliography should be provided by the authors, not just a bibliography of work that agrees with their thesis.

Under the circumstances, the authors of this £6 million study – which used taxpayers’ funds – are being suspiciously coy. Patients have insisted for years that the CBT/GET protocol is not just meaningless – it is directly harmful. Indeed, if CBT/GET were a pharmaceutical drug instead of a protocol, it would have been denied a long time ago on the basis of the number of adverse events.

But both the UK and the US governments continue to recommend this treatment – and they base that recommendation on the PACE trials plus the body of literature written by the schools of psychiatry at QMUL and KCL.

It is not just an academic discussion. Policy choices rest on the conclusion. Treatment choices rest on the conclusions.

It is imperative that we get this right. If the authors are wrong, then this is actually harming patients, even as I write this sentence. They would probably consider that sentence harassment. But how else am I to say it? There is evidence that the adverse events from this treatment protocol are being swept under the rug.

One million American adults suffer from this disease. 250,000 patients in the UK are also victims. This is too important not to make absolutely certain we are doing the right thing.

What I do not understand is why the psychiatrists at QMUL and KCL don’t agree with that.