Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-COVID Syndrome: A Common Neuroimmune Ground? Abstract: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating chronic disease of unknown etiology, sharing a similar clinical presentation with the increasingly recognized post-COVID syndrome. We performed the first cross-sectional study of ME/CFS in a community population in Russia. Then we described and compared some clinical and pathophysiological characteristics of ME/CFS and post-COVID syndrome as neuroimmune disorders. Of the cohort of 76 individuals who suggested themselves as suffering from ME/CFS, 56 were diagnosed with ME/CFS by clinicians according to ≥1 of the four most commonly used case definitions. Of the cohort of 14 individuals with post-COVID-19 syndrome, 14 met the diagnostic criteria for ME/CFS. The severity of anxiety/depressive symptoms did not correlate with the severity of fatigue either in ME/CFS or in post-COVID ME/CFS. Still, a positive correlation was found between the severity of fatigue and 20 other symptoms of ME/CFS related to the domains of “post-exertional exhaustion”, “immune dysfunction”, “sleep disturbances”, “dysfunction of the autonomic nervous system”, “neurological sensory/motor disorders” and “pain syndromes”. Immunological abnormalities were identified in 12/12 patients with ME/CFS according to the results of laboratory testing. The prevalence of postural orthostatic tachycardia assessed in the active orthostatic test amounted to 37.5% in ME/CFS and 75.0% in post-COVID ME/CFS (the latter was higher than in healthy controls, p = 0.02). There was a more pronounced increase in heart rate starting from the 6th minute of the test in post-COVID ME/CFS compared with the control group. Assessment of the functional characteristics of microcirculation by laser doppler flowmetry revealed obvious and very similar changes in ME/CFS and post-COVID ME/CFS compared to the healthy controls. The identified laser doppler flowmetry pattern corresponded to the hyperemic form of microcirculation disorders usually observed in acute inflammatory response or in case of systemic vasoconstriction failure. https://www.mdpi.com/2075-4418/13/1/66 Peer-Review Record https://www.mdpi.com/2075-4418/13/1/66/review_report
Yes, and from the abstract, a well-informed team. Varvara A. Ryabkova 1,2,* Natalia Y. Gavrilova 1, Tamara V. Fedotkina 1,3, Leonid P. Churilov 1,4, Yehuda Shoenfeld 1,5,6 1 Laboratory of the Mosaic of Autoimmunity and Department of Pathology, Saint Petersburg State University, 199034 Saint-Petersburg, Russia 2 Department of Hospital Therapy Named after Academician M.V. Chernorutskii, Research Institute of Rheumatology and Allergology, Pavlov First Saint Petersburg State Medical University,197022 Saint-Petersburg, Russia 3 National Medical Research Center Named after V. A. Almazov, 197341 Saint Petersburg, Russia 4 Saint Petersburg Research Institute of Phthisiopulmonology, 191036 Saint Petersburg, Russia 5 Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Tel-Hashomer, Ramat-Gan 52621, Israel 6 Ariel University, Ariel 98603, Israel This is interesting
Orthostatic testing Interesting and matches my experience - I wonder how many OI studies have controlled for that. Test was a supine to standing test, 10 minutes of standing Smart analysis - they found it was the sustained increase in heart rate that differentiated the OI in the disease participants from the controls edit to add: Immune cells Nothing much there I think, in very small samples, apart from this
It's actually completely meaningless, I think, @Hutan. As are the data on interferons I think. One of the authors here is a serious red flag in autoimmune research.
Microcirculation A non-invasive study of blood microcirculation parameters using the LDF method was carried out on 10 participants from cohort 1, 7 participants from cohort 2, and 7 healthy individuals. Laser doppler flowmetry Flow of blood is influenced by 1. passive mechanisms (in terms of the blood vessel): the pulse from the heart and the respiratory pump (I assume movement of the body due to breathing), and 2. active mechanisms - oscillations of the vessel due to sympathetic nerve fibres, smooth muscle in the vascular wall and molecules from the endothelium M—average value of tissue perfusion with blood, σ—mean square deviation of M oscillations in a given time interval, vALF—contribution of low-frequency oscillations (0.05–0.2 Hz) to the total power of the spectrum of biorhythms; vAHF— contribution of high-frequency oscillations (0.2–0.4 Hz) to the total power of the spectrum of biorhythms; vACF—contribution of pulse frequency oscillations (0.8–1.6 Hz) to the total power of the biorhythms; IFM—the oscillation index; R—vascular resistance; CT—microvascular tone, r—effect size. (There seems to be an error with the headings for the p values - I think the last column should be 1st versus 2nd ie ME/CFS versus post-covid ME/CFS) So, they conclude that there is congestion of the tissue with blood in both ME/CFS and post-Covid ME/CFS. They suggest the increased vascular resistance found in ME/CFS might be a product of the time chronic inflammatory processes have existed.
Re the laser doppler flowmetry There certainly was less there than I had hoped. You don't think the technique is useful? I don't know if it is a validated method or not.
I am afraid it is just a word salad, @Hutan. Anyone familiar with the clinical pathology of inflammation can see that they do not actually think through what they are saying. If there is inflammation with increased flow the bit goes pink and warm - you can see it and feel it. I haven't even worked out which bit of the person they are 'measuring'.
I get the impression that this is a team of people, probably some of whom have personal experience of ME/CFS, trying to fight for recognition in a society that, like most places, has dismissed ME/CFS as psychosomatic and just a version of depression. In that context, it's not surprising that anything remotely looking like evidence would be reported with enthusiasm. We've seen worse efforts to investigate and describe ME/CFS.
