Usefulness of an abnormal cardiovascular response during low-grade head-up tilt-test for ... adolescents with chronic fatigue ..., 2007, Wyller et al

Hutan

Hutan

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Usefulness of an abnormal cardiovascular response during low-grade head-up tilt-test for discriminating adolescents with chronic fatigue from healthy controls
Vegard Bruun Wyller 1, Reidar Due, J Philip Saul, Jan P Amlie, Erik Thaulow
2007

https://pubmed.ncbi.nlm.nih.gov/17398200/

Hemodynamic dysfunction is documented in chronic fatigue syndrome (CFS). This study was conducted to investigate cardiovascular responses to orthostatic stress in adolescents with CFS, using a novel procedure for tilt-table testing. A total of 27 adolescents with CFS and 33 healthy control subjects with equal age and gender distribution underwent 15 minutes of 20 degrees head-up tilt testing. Heart rate, systolic blood pressure (BP), mean BP, diastolic BP, stroke index, total peripheral resistance index, end-diastolic volume index, and acceleration index were continuously and noninvasively recorded.

At rest, patients with CFS had higher total peripheral resistance index values (p<0.01) and lower stroke index and end-diastolic volume index values (p<0.05) than controls. During 20 degrees head-up tilt testing, patients with CFS had greater increases in heart rate, diastolic BP (p<0.001), mean BP (p<0.01), and total peripheral resistance index (p<0.05) than controls and greater decreases in stroke index (p<0.05). Syncope or near syncope was not observed. In conclusion, this study found that adolescents with CFS have significant abnormalities of cardiovascular regulation in response to mild orthostatic stress, differentiating them from healthy controls.
 
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From 2007, in case you missed that. And I think that's the BPS Wyller.

To repeat the conclusion:
this study found that adolescents with CFS have significant abnormalities of cardiovascular regulation in response to mild orthostatic stress, differentiating them from healthy controls.

Here is an objective measure, known about for years, why has it not been included as an outcome in treatment trials?

20 degrees is hardly any degree of tilt - so the laughable 'fear of standing' idea that has been proposed to explain OI in ME/CFS doesn't apply.
 
Just looking at the abstract posted I am not sure this shows anything. I think it might simply indicate an adrenaline surge in patients.

If you put patients and healthy people in a strange contraption supposedly to 'test' for signs of illness you are likely to get different adrenaline output in people who understand that they are ill and people who see themselves as well and just there as 'controls'.

Fifteen minutes of 20 degree tilt seems to me to be hard to interpret. The effect on physiology may have more to do with being immobilised in one position than anything to do with tilt. There may be a lot more in the paper.

The conclusion from Wyller might well be that PWME are more easily stressed but do not actually pass out. But they will be more stressed simply because the situation is more stressful than for controls.
 
Could that problem of an adrenaline surge in the patient's be overcome using several different angles for a few minutes each and looking for a dose response? If it's purely stress based adrenaline surge causing the cardiovascular signs, then the response should be the same regardless of angle of tilt.
And change the order - start them at, say 10%, then make the tilt go to horizontal as though that were the test.
 
If you click on the Wyller link, you will see that he did a whole lot of investigations in young people with CFS. It could be interesting to pick through them - maybe there are some clues as to where he started and how he got to where he is now, with respect to ME/CFS. Maybe our Norwegian members have some insights.

I thought this other paper in particular was worth a look.

Elevated nocturnal blood pressure and heart rate in adolescent chronic fatigue syndrome
Harald Hurum 1, Dag Sulheim, Erik Thaulow, Vegard Bruun Wyller
2011

Aim: To compare ambulatory recordings of heart rate (HR) and blood pressure in adolescents with chronic fatigue syndrome (CFS) and healthy controls. We hypothesized both HR and blood pressure to be elevated among CFS patients.

Methods: Forty-four CFS patients aged 12-18 years were recruited from our paediatric outpatient clinic. The controls were 52 healthy adolescents having similar distribution of age and gender. 24-h ambulatory blood pressure and HR were recorded using a validated, portable oscillometric device.

Results: At night (sleep), HR, mean arterial blood pressure and diastolic blood pressure were significantly higher in CFS patients as compared with controls (p < 0.01). During daytime, HR was significantly higher among CFS patients (p < 0.05), whereas blood pressures were equal among the two groups.

Conclusions: The findings support previous experimental evidence of sympathetic predominance of cardiovascular control in adolescent CFS patients. Also, the findings prompt increased focus on cardiovascular risk assessment and suggest a possible target for therapeutic intervention.
 
Figure 1. Mean changes in cardiovascular variables (based on coherent averaging of individual recordings) in controls (black) and patients with CFS (red) during a 20° HUT. Shaded areas, 95% confidence intervals for the mean (shown for clarity, although the consecutive data points are not independent of one another). Data are normalized to zero for the first time period. The time axis is adjusted so that zero corresponds to the start of tilting. ACI = acceleration index; MBP = mean BP; SI = stroke index.
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From the discussion —

The most important findings in this study are that (1) at rest, patients with CFS have higher HRs, higher TPRI [Total Peripheral Index] values, lower stroke index values, and lower EDVI [End-Diastolic Volume Index] values than controls; and (2) during orthostatic stress, patients with CFS have larger increases in HR, mean BP, diastolic BP, and TPRI, no decreases in acceleration index, and larger decreases in stroke index than controls. These deviations were strikingly homogenous within the patient group and significantly different from controls, despite the small number of subjects studied and the application of very mild orthostatic stress.
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Moderate hypovolemia, which indeed has been found in 1 study of CFS, can explain all the findings. An alternative explanation is a general enhancement of sympathetic efferent activity due either to changes in peripheral autonomic neuronal control or to changes in the brainstem cardiovascular control center. If so, the reduced EDVI and stroke index must be attributed to increased HR and reduced diastolic filling time.
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The findings during the HUT appear to indicate an enhanced sympathetic response to orthostatic stress in the patients with CFS. A reduction in acceleration index, as observed in controls, is expected because of reduced cardiac filling and thereby reduced ventricular performance according to the Frank-Starling mechanism. A tendency toward increased acceleration index, as observed in patients with CFS, therefore points to an increased cardiac inotropic effect, further indicating a general enhancement of cardiovascular sympathetic efferent activity. Moderate hypovolemia and cardiovascular deconditioning are possible explanations for these findings as well.
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Hutan said:
Here is an objective measure, known about for years, why has it not been included as an outcome in treatment trials?
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It look like these were just greater increases in heart rate and blood pressure in the ME/CFS group compared to healthy controls. Perhaps it could be the result of deconditioning/being less fit?
 
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