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Who said: 80% of ME is post-infectious

Discussion in 'Immunological' started by JaimeS, Dec 21, 2018.

  1. Snow Leopard

    Snow Leopard Senior Member (Voting Rights)

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    No, I'm just saying that there is a long list of infections associated and overly focusing on the specifics of one of them might be a waste of time.
     
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  2. Hip

    Hip Senior Member (Voting Rights)

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    It's a relatively short list: the primary ones appear to be coxsackievirus B, echovirus, Epstein-Barr virus, cytomegalovirus and HHV-6.

    I agree though that one should be looking at other possible mechanisms as well as viral causes. For example, ME/CFS might involve an exaggerated over-sensitized immune response to these viruses. So there may be a chronic viral infection, but it might take that in combination with an exaggerated immune response to create ME/CFS. So then you would want to investigate why the immune system has become sensitized.
     
    Last edited: Dec 24, 2018
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  3. weyland

    weyland Established Member

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    Similar figure referenced in the ICC primer.

    973EF55D-D0CC-4E92-9F5E-BB176922D855.jpeg
     
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  4. Vertical

    Vertical Established Member

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    The CDC estimates that 90% of PWCs are not as yet diagnosed. Therefore, an 80% (or other) calculation for cause is a non-sequitur, sic having seen only 10% of probable cases.
     
    Last edited: Dec 27, 2018
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  5. Snow Leopard

    Snow Leopard Senior Member (Voting Rights)

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    I'm not sure this "90%" is generalisable at all. Such claims were made based on studies in the 90s when medical practitioners had less knowledge or confidence to make a CFS diagnosis.

    I think diagnosis rates vary greatly by region and access to (appropriate) medical care. The recent CDC study (ongoing) claims much higher current or past diagnosis (1+% of total population), so in the region of that study at least, I doubt there are many people who are undiagnosed as a proportion of people with the illness overall.

    There are of course biases based on the sample used, whether it is a population or community based sample, a prospective sample (people who start off healthy), or people recruited from primary or secondary medical care. What was interesting though was how many studies came up with a figure of somewhere around 80% - it wasn't just one.
     
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  6. wastwater

    wastwater Senior Member (Voting Rights)

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    Last edited: Jan 9, 2019
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  7. Mithriel

    Mithriel Senior Member (Voting Rights)

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    The CDC may be better now, but their research is very dodgy. They used the "Reeves operationialised definition of ME" which was, well who knows, really, I think it involved how you felt in the last 4 weeks. They did phone surveys where people had not realised they had CFS which makes no sense. When we read 80% undiagnosed we think of poor souls suffering but being fobbed off by their doctors not people who did not know they were ill.

    Until very recently, at least I hope it is better now, the CDC worked just as hard to trivialised and widen CFS as the UK BPSers.
     
  8. JaimeS

    JaimeS Senior Member (Voting Rights)

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    CDC has a prevalence study underway?
     
  9. JaimeS

    JaimeS Senior Member (Voting Rights)

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    Lenny Jason did this exact thing -- prevalence via phone call is sometimes the best you can do when working with vast swaths of people. Many of them met the criteria for CFS that he had created using his epi survey, even though they had not been diagnosed.

    I've been thinking about this myself and every possible option will be criticized for its pitfalls.

    ICD code / diagnosis?
    What does a GP know about ME, anyhow? Probably a significant number of these diagnoses are wrong.​
    Queries via phone call?
    What was asked? How does that even work? And don't we think this selects for people who are wealthy enough to stay at home when they're sick? Or who are retired and no longer work? A vanishingly small number of people, mostly older individuals even pick up the phone if they don't recognize the number. Robocalls have become too common.​
    Diagnosed by a specialist at a particular center?
    Ah, but who knows which diagnosis they like best, or how they conceptualize the disease? Rife with bias, as clinicians tend to have a very clear mental picture of what ME "is" -- I've only encountered a small number who are less certain. They'll select for the same type of patient.​
    Some combination of the above? ICD first, follow-up call second?
    Costs an enormous amount of money in manhours and will therefore be criticized as being too small a study and therefore meaning nothing; will be criticized for the individual flaws within each part of the process.
    Ideally, you'd get hundreds of people diagnosed individually by a variety of expert clinicians.

    Good luck with the funding for that! :confused:
     
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  10. JaimeS

    JaimeS Senior Member (Voting Rights)

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    Ahhhhhhomg okay.

    So prevalence CAN BE DONE RIGHT in a disease like ME!

    I found the CDC's four-year prevalence study for autism, started in 2014 and finished up just last year (a four-year study). Here's how they did it:

    First, they connected with state and local governments in order to get permission to acquire all kinds of data. They did so in 11 different states in order to do their best to get data from different places in the country. Even so, they acknowledge that this can't represent the whole country for real, and so prevalence will be their best estimate.

    Then, they pulled "is someone potentially autistic?" from numerous, numerous sources. Not just ICD code -- it included school reports, doctor's reports, hospital admissions -- and lookalike diagnoses -- along with actual diagnoses of autism.

    Finally, they compiled vast swaths of data on each of these individuals and handed them off to trained, expert clinicians and said, "based on your best judgment, do this person's results mean they are autistic?"

    This is probably the only way to do it short of actually interviewing millions of people in person.

    I chose autism because there are a lot of similarities in terms of epidemiological issues:
    • There is no biomarker for autism
    • Symptoms present very differently, person to person
    • They have numerous diagnostic criteria and there is argument over which are valid.
    Good case study for us.
     
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  11. Mithriel

    Mithriel Senior Member (Voting Rights)

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    The phone surveys I am thinking about found people who did not realise they were ill. They only asked if people had felt more fatigued than usual in the past 4 weeks. These were not people who were trailing round doctors trying to find the answer to why they felt so bad.
     
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  12. Webdog

    Webdog Senior Member (Voting Rights)

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  13. JaimeS

    JaimeS Senior Member (Voting Rights)

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    Lots of reasons, none of which are helpful to us. It's rather dizzying actually.
     
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