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Williams, White et al: PACE: Heterogeneity in CFS - empirically defined subgroups [...]

mango

Senior Member
Messages
905
Heterogeneity in chronic fatigue syndrome - empirically defined subgroups from the PACE trial.

Williams TE
1, Chalder T 2, Sharpe M 3, White PD 1.

Author information

  1. Centre for Psychiatry, Wolfson Institute of Preventive Medicine, Barts and the London School of Medicine, Queen Mary University of London, London,UK.
  2. Academic Department of Psychological Medicine,King's College London, Weston Education Centre,London,UK.
  3. Department of Psychiatry,Psychological Medicine Research, University of Oxford,Oxford,UK.
Psychol Med. 2017 Jan 23:1-12. doi: 10.1017/S0033291716003615. [Epub ahead of print]

Abstract

BACKGROUND:
Chronic fatigue syndrome is likely to be a heterogeneous condition. Previous studies have empirically defined subgroups using combinations of clinical and biological variables. We aimed to explore the heterogeneity of chronic fatigue syndrome.

METHOD:
We used baseline data from the PACE trial, which included 640 participants with chronic fatigue syndrome. Variable reduction, using a combination of clinical knowledge and principal component analyses, produced a final dataset of 26 variables for 541 patients. Latent class analysis was then used to empirically define subgroups.

RESULTS:
The most statistically significant and clinically recognizable model comprised five subgroups. The largest, 'core' subgroup (33% of participants), had relatively low scores across all domains and good self-efficacy. A further three subgroups were defined by: the presence of mood disorders (21%); the presence of features of other functional somatic syndromes (such as fibromyalgia or irritable bowel syndrome) (21%); or by many symptoms - a group which combined features of both of the above (14%). The smallest 'avoidant-inactive' subgroup was characterized by physical inactivity, belief that symptoms were entirely physical in nature, and fear that they indicated harm (11%). Differences in the severity of fatigue and disability provided some discriminative validation of the subgroups.

CONCLUSIONS:
In addition to providing further evidence for the heterogeneity of chronic fatigue syndrome, the subgroups identified may aid future research into the important aetiological factors of specific subtypes of chronic fatigue syndrome and the development of more personalized treatment approaches.

KEYWORDS:
Chronic fatigue syndrome; heterogeneity; latent class analysis; nosology; subgroups

DOI: 10.1017/S0033291716003615

https://www.ncbi.nlm.nih.gov/pubmed/28112075
 
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deleder2k

Senior Member
Messages
1,129
Great study. So great. Truly amazing. Done by one of of the best researchers that God ever created. This study is good. It is actually so good that the patients will call the researchers and say: "Please, researchers, stop doing all these good studies. All the good research is just too much. You're making us too healthy with you're research. You've spent your research grants too good the last years. We can't stand it anymore. Patients in U.K are sick of all the greatness seen in ME research in the U.K." They make so much difference for the patients. If they continue like this they won't have ME patients left in about 200000000 years. That would be a pity.

Best regards from Donald JT
 
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A.B.

Senior Member
Messages
3,780
Yesterday they wanted to lump all patients into the same category, now they are suddenly interested in defining subgroups. I wonder what happened that changed their mind? Was it perhaps two large trials that showed CBT/GET don't work for anyone except maybe a few percent of a "fatigue" cohort?
 
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Hajnalka

Senior Member
Messages
910
Location
Germany
Haha, at first glance I thought: subgroups, that's interesting - autoimmune, viral etc. Not quite what I expected. ;)
The smallest 'avoidant-inactive' subgroup was characterized by physical inactivity, belief that symptoms were entirely physical in nature, and fear that they indicated harm (11%).
Yawn, this is getting so old, not even upsetting anymore, just boring. It will be so embarrassing for them, once PACE will be retracted.
 

A.B.

Senior Member
Messages
3,780
Yes, let's not fall prey to unreasonable optimism. Judging by their past behaviour by developing subgroup specific treatments they are most likely talking about different flavors of psychotherapy. Now that vanilla CBT/GET is rapidly approaching its expiration date, they are looking for new therapies to sell.
 
Messages
44
I have only read the abstract as when I try to get to the article it says "Page not found". I wonder are they saying that only a subgroup of 11% of participants are avoidant-inactive? If so , then the results of the trial have been very poorly communicated.
 

Hajnalka

Senior Member
Messages
910
Location
Germany
Judging by their past behaviour by developing subgroup specific treatments they are most likely talking about different flavors of psychotherapy.
Of course! It has proven to be the most efficient treatment - and save. They just want to help. Because CFS patients suffer and the symptoms feel very real to them. They will not stop helping us just because militant activists (like you apparently) think it's entirely physical in nature. ;)
 

ash0787

Senior Member
Messages
308
Let me tell you folks, you're gonna be so proud of your researchers, so proud,

All these researchers packing up and going to biomedical because theres just not enough government support
for social scientists, such a shame.

People often ask me, how do you do it, how are you so successful ? the key has always been to take 10 year old disreputable studies and selectively use the non empirical data to support our biases.

Make Psychiatry Great Again
 

Jonathan Edwards

"Gibberish"
Messages
5,256
It is of course very interesting that a sample of people who agreed to take part in a trial in which they might be randomised to graded exercise therapy contained rather few people who were inactive and afraid of over-exertion. It adds further evidence to the belief that common sense is common sense.
 
Messages
2,391
Location
UK
Variable reduction, using a combination of clinical knowledge and principal component analyses, produced a final dataset of 26 variables
There is obviously a lot of PACE data that was not released. There are 12 variables in the released PACE data, and there were evidently more (many more?) than 26 collected for the trial.

I really do feel that for any published results, all the underlying data should be made available for open peer review. (I mean - they cannot be worried about the wider scientific community seeing the whole picture ... can they?!:rolleyes:).

Also: "... using a combination of clinical knowledge ...", um ... how well do we trust this?
 
Messages
2,158
I suspect this is part of the foundation on which they want to build MEGA - a paper to cite that demonstrates there are definable subgroups within CFS.

The fact that their subgroups make no sense at all is, for that purpose, irrelevant.

Actually reading the abstract, I conclude they have lost altogether any detectable signs of intelligence, reason and logic and sanity.

It's utter garbage.
 

Forbin

Senior Member
Messages
966
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Sidereal

Senior Member
Messages
4,856
Chronic fatigue syndrome is likely to be a heterogeneous condition.

Actually, recent research is showing that there's a common underlying metabolic picture in real ME/CFS (regardless of superficial heterogeneity in onset, symptoms etc.) so 'chronic fatigue syndrome' will likely turn out to be one disease + a bunch of misdiagnoses.

The smallest 'avoidant-inactive' subgroup was characterized by physical inactivity, belief that symptoms were entirely physical in nature, and fear that they indicated harm (11%).

:lol:
 

user9876

Senior Member
Messages
4,556
There is obviously a lot of PACE data that was not released. There are 12 variables in the released PACE data, and there were evidently more (many more?) than 26 collected for the trial.
A lot of data was collected. The FoI was restricted to a very limited set of data. It was sufficient for checking the recovery results but limited hence avoiding privacy issues.