January 19, 2016
The scientific debate about the PACE trial continues with the publication of three letters in the Lancet Psychiatry journal this week.
Prof James Coyne and Prof Keith Laws argue that “although the PACE programme of cognitive behavioural therapy (CBT) or graded exercise therapy (GET) led patients to report less fatigue or greater physical function than patients in the adaptive pacing therapy and specialist medical care groups in the short term, evidence in the long-term follow-up is unconvincing.”
M.E. advocate Frank Twisk questions the criteria used by the researchers who carried out the trial, before discussing the application of subjective measures and, like Profs Coyne and Laws, the follow-up data.
Dr Charles Shepherd refers to a recent patient survey, undertaken by the ME Association, which found that 73% of respondents reported that CBT had no effect on their symptoms and 74% that their symptoms were made worse by GET. He says: “The argument here is not with psychiatry. Mental illness is just as real and horrible as physical illness, and as with any long-term illness, some people with M.E./CFS develop comorbid depression and other mental health problems. The argument is with a flawed model of causation that takes no account of the heterogeneity of both clinical presentations and disease pathways that come under the umbrella diagnosis of M.E./CFS along with the conclusion that CBT and GET should to be used as one size fits all primary interventions for everyone with mild or moderate symptoms."
In their response to these three letters, the PACE trial authors discuss their methodology and address issues raised about follow-up, stating: "Our more recent article reporting long-term patient outcomes found that improvement was maintained for those originally allocated to CBT or GET. While recovery for all participants receiving these treatments has never been claimed, a mean improvement of approximately 20 points on the medical outcomes study short-form 36 (SF-36) physical functioning scale from trial entry is, contrary to Frank Twisk's comments about the lack of treatment effect, clearly clinically meaningful. Nor is its value to patients negated by Coyne and Laws' reference to mean SF-36 scores from selected cross-sectional studies of patients with other illnesses."