Trial Report Worsening Symptoms Is Associated with Larger Cerebral Blood Flow Abnormalities during Tilt-Testing in ME/CFS, 2023, van Campen

https://www.mdpi.com/1648-9144/59/12/2153

Worsening Symptoms Is Associated with Larger Cerebral Blood Flow Abnormalities during Tilt-Testing in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)
by
C. (Linda) M. C. van Campen
1,*,
Peter C. Rowe
2 and
Frans C. Visser
1


1 Stichting CardioZorg, Planetenweg 5, 2132 HN Hoofddorp, The Netherlands
2 Department of Pediatrics, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA
*Author to whom correspondence should be addressed.
Medicina 2023, 59(12), 2153; https://doi.org/10.3390/medicina59122153
Submission received: 19 November 2023 / Revised: 6 December 2023 / Accepted: 11 December 2023 / Published: 12 December 2023

Abstract

Background and Objectives:

During tilt testing, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) patients experience an abnormal reduction in cerebral blood flow (CBF).

The relationship between this CBF reduction and symptom severity has not been examined in detail.

Our hypothesis was that ME/CFS severity is related to the degree of the CBF reduction during tilt testing.

Materials and Methods:

First, from our database, we selected ME/CFS patients who had undergone assessments of ME/CFS symptomatology and tilt tests on the same day, one at the first visit and the second during a follow-up.

The change in symptomatology was related to the change in CBF during the tilt test.

Second, we combined the data of two previously published studies (n = 219), where disease severity as defined by the 2011 international consensus criteria (ICC) was available but not published.

Results:

71 patients were retested because of worsening symptoms.

The ICC disease severity distribution (mild-moderate-severe) changed from 51/45/4% at visit-1 to 1/72/27% at follow-up (p < 0.0001).

The %CBF reduction changed from initially 19% to 31% at follow-up (p < 0.0001). Of 39 patients with stable disease, the severity distribution was similar at visit-1 (36/51/13%) and at follow-up (33/49/18%), p = ns.

The %CBF reduction remained unchanged: both 24%, p = ns. The combined data of the two previously published studies showed that patients with mild, moderate, and severe disease had %CBF reductions of 25, 29, and 33%, respectively (p < 0.0001).

Conclusions:

Disease severity and %CBF reduction during tilt testing are highly associated in ME/CFS: a more severe disease is related to a larger %CBF reduction.

The data suggest a causal relationship where a larger CBF reduction leads to worsening symptoms.


Keywords:
orthostatic intolerance; tilt-table testing; ME/CFS; stroke volume index; cardiac index; cerebral blood flow; disease severity; symptom worsening

 

They looked at historical records from their clinic for patients who had taken two tilt tests. They divided the records into two groups, those who had no change in symptoms at the second visit (n=39) and those who had worsened symptoms at the second visit (n=71). They looked at how much their cerebral blood flood (CBF) reduction differed between the two tests.

Though while they say that there were 71 in the worsened group in the text and Table 1, this figure that shows the group level values says n=68 without explaining why.


Looking at the following figure, no overall difference in CBF reduction in the group with unchanged symptoms. In the worsened symptom group, I only see a single participant that didn't have a greater reduction.


That's a surprisingly close relationship between worsening symptoms and greater CBF reduction. Either 68/69 or 70/71 (~98.5%) participants who reported worsening symptoms also had greater reduction.

Going back to the methods in the abstract:

That second sentence is strange. At first read, I thought they were reporting the results of this study. But it's in the methods section. Did they select participants based on whether their change in symptoms was associated with change in CBF reduction? Even though that was the outcome of this study? That would be like picking only people who improved from a drug for a study, then reporting that the drug causes improvement in everyone.

From discussion:

 

That is a little strange. But the method suggests that grouping was entirely due to the change in symptoms through the application of the ICC criteria. The combination of long-COVID and hypermobile patients into the ME/CFS basket was curious though.

 

That part was studied separately from the clinic health records, and it seems like they all fit ICC. They're from two previous van Campen studies on ME/CFS.

• Van Campen, C.L.M.C.; Rowe, P.C.; Visser, F.C. The myalgic encephalomyelitis/chronic fatigue syndrome patients with joint hypermobility show larger cerebral blood flow reductions during orthostatic stress testing than patients without hypermobility: A case control study. Med. Res. Arch. 2021, 9. [Google Scholar] [CrossRef]
• Van Campen, C.L.M.C.; Visser, F.C. Long-haul covid patients: Prevalence of pots are reduced but cerebral blood flow abnormalities remain abnormal with longer disease duration. Healthcare 2022, 10, 2105. [Google Scholar] [CrossRef] [PubMed]

Edit: Linked wrong study before.

 

I emailed Dr. van Campen about this since I wanted to confirm if it was placed in the methods section by accident.

She said it was on purpose, and I realized "related" can mean a technique, as well as a descriptor. So they meant:

All this about CBF reduction is looking quite interesting. I wonder if any other groups have seen similar results.