Snow Leopard
Senior Member (Voting Rights)
About the only piece of data we are presented with is that Wyller found PWME to have higher sympathetic activity than normal controls on clinical testing. I would not be at all surprised if PWME had higher sympathetic activity than normal people when experimented on by Dr Wyller. The psychological context of the situation would be completely different for the two groups.
LOL
The key finding was higher norepinephrine and epinephrine in adolescents at baseline. The other findings were during orthstatic stress/exercise, which probably just reflect relative deconditioning of patients vs controls. There is talk of shifted LF/HF balance of heart rate RR‐interval (RRI) variability, but this seems to be more of a reduction in HF and parasympathetic activity, rather than increase in sympathetic activity.
Likewise, his findings of both increased plasma norepinephrine and epinephrine or other signs of increased sympathetic activity not been replicated in adults. In another study by Wyller et al. they found no difference in Heart rate variability LF power, HF power or LF/HF-ratio, or cortisol, but did find increased plasma catecholamines, albeit with substantial variation between patients (suggesting it is not a sensitive predictor).
No difference in plasma norepinephrine in adults and likewise, in another study. Another study found lower plasma epinephrine at baseline in adults.
It is notable that Wyller's proposed solution failed in a clinical trial. Catecholamine levels were reduced, but symptoms of some patients got significantly worse and notably, symptoms of orthostatic intolerance did not change. This let do the conclusion that the changes that Wyller et al had observed were likely compensation mechanisms. Yet he seems to have forgotten about that conclusion.
All of this combined suggests that the "sustained arousal" may indeed be an artifact of the clinical context of Wyller et al, (specifically, adolescent patients feeling more anxious during the testing) because that is the only group who is consistently measuring differences in catecholamines.