Advancing ME/CFS Research: Identifying Targets for Intervention and Learning from Long COVID Dec. 12-13, 2023

Discussion in 'General ME/CFS news' started by Jaybee00, Nov 30, 2023.

  1. SNT Gatchaman

    SNT Gatchaman Senior Member (Voting Rights)

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    See also abstract from a 2022 ISMRM presentation: Lower Cerebral Venous Oxygenation in Post-acute Sequelae of COVID-19 (I can't find a subsequent publication)

    These findings suggesting increased oxygen extraction in the brain are opposite to findings indicating impaired peripheral oxygen extraction for muscles.
     
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  2. Dolphin

    Dolphin Senior Member (Voting Rights)

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    Sean likes this.
  3. SNT Gatchaman

    SNT Gatchaman Senior Member (Voting Rights)

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    I just watched this again, attempting to gather info on how POT(S) / OI / cerebral blood flow could be coherently understood (Day 2 @ 3h 07m).

    Note that they found differences in LC vs HC but not CFS vs HC/LC. Apart from the disease duration differences, the "CFS" patients may therefore be less well characterised and some may not fulfil modern criteria for ME/CFS with PEM, while perhaps it's more likely that the LC cohort does. We'll have to wait for a publication to evaluate that.

    My summary notes —

    - Used Fukuda for LC and CFS inclusion, with LC needing confirmed infection and subsequent ongoing symptoms

    - TRUST (T2 Relaxation Under Spin-Tagging)
    - Measures venous oxygenation (Yv) - superior sagittal sinus (ie SvO2)
    - Compare against SpO2 as surrogate for arterial oxygenation (Ya)

    - OEF (Oxygen Extraction Fraction)
    - OEF = Ya - Yv
    - Yv decreased in LC, not CFS
    - OEF increased in LC, not CFS
    - But note outliers in CFS

    - CMRO2 (Cerebral metabolic rate of oxygen consumption)
    - "Remarkably well-conserved in normal conditions"
    - CMRO2 = Ca x CBF x OEF
    - Ca is a constant representing the amount of oxygen-carrying molecules per unit volume of blood
    - If OEF increased then accompanied by decreased CBF

    - CBF measured by phase-contrast MRI of the 4 arteries (carotid, vertebrals)
    - No significant differences between HC/LC/CFS
    - But one LC low outlier

    - Physical functioning positively correlated with SvO2 (Yv)
    - General fatigue is negatively correlated with SvO2 (Yv)
     
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