Mental Stress and Autonomic nervous system functioning in CFS

[Cort]

Just reading the words he uses is so interesting. Look at this

There is accumulating evidence of altered cardiovascular autonomic responses to different somatic stressors, in particular orthostatic stress,

I've never thought of standing as a "somatic stressor"; I had always thought of somatic as reflecting stress associated with the mind. On the other hand somatic simply refers to 'stress', I believe, and there is of course the stress of standing, the stress of physical exercise, etc... There appears to be more to 'somatism' which is the study of the stress response I think - than I had thought.

IN this small study he did not find that doing simple arithmetic tasks altered blood pressure, skin blood flow in people with CFS. He did find that heart rate as increased at baseline - so there is evidence of autonomic dysfunction.

What he probably should have done I would guess is really stress them...give them the test several times over the course of the day and see what happens at the end of the day. We know that even exercise to exhaustion tests don't start showing their full effects until the next day and you try it again.

The problem with these kind of one-off tests is that not only do they not show much but that they don't reflect real life and they give some medical professionals the opportunity to say -See there's nothing wrong...

Wyller keeps pumping stuff out though and some of it is really interesting

Biopsychosoc Med. 2010 Dec 14;4(1):22. [Epub ahead of print]
No differences in cardiovascular autonomic responses to mental stress in chronic fatigue syndrome adolescents as compared to healthy controls.
Egge C, Wyller VB.

Abstract

ABSTRACT: Chronic fatigue syndrome (CFS) is a disabling disease with unknown etiology. There is accumulating evidence of altered cardiovascular autonomic responses to different somatic stressors, in particular orthostatic stress, whereas autonomic responses to mental stress remain to be investigated.

In this study, we explored cardiovascular autonomic responses to a simple mental stress test in CFS patients and healthy controls. A consecutive sample of 13 patients with CFS, aged 12 to 18 years, and a volunteer sample of 53 healthy control subjects of equal age and gender distribution were included.

Blood pressure, heart rate and acral skin blood flow were continuously recorded during an arithmetic exercise. At baseline, heart rate was significantly higher among CFS patients than controls (p = 0.02). During the arithmetic exercise, however, there were no significant differences in the responses between the two groups. In conclusion, CFS patients have unaltered autonomic responses to simple mental stress as compared to healthy control subjects.

 

[Dolphin]

Link to full text (provisional)

Link to full text (provisional):
http://www.bpsmedicine.com/content/pdf/1751-0759-4-22.pdf

Final version will be at: http://www.bpsmedicine.com/content/4/1/22

 

[Cort]

Excellent - thanks for 'leaping in there' Dolphin....

 

[Dolphin]

No problem, Cort. What are dolphins for.

 

[Esther12]

Ta.

 

[biophile]

Just another "chronic fatigue" study?

Thanks Dolphin for the full text.

This study is somewhat disappointing. While their hypothesis and conclusion was interesting (that autonomic reactivity in adolescent CFS patients is sensitive to only physical stresses rather than mental stresses), they mention confounding factors which erode my confidence in the study. Unless I misread, their "CFS" patients didn't require any other symptoms besides idiopathic chronic fatigue, which isn't a good sign when considering they state that their previous studies on autonomic reactivity used the same patients. They also did not control for test performance or activity levels, and noted (as Cort pointed out) that the mental tests may not have been stressing enough.

Cort says:

I've never thought of standing as a "somatic stressor"; I had always thought of somatic as reflecting stress associated with the mind. On the other hand somatic simply refers to 'stress', I believe, and there is of course the stress of standing, the stress of physical exercise, etc... There appears to be more to 'somatism' which is the study of the stress response I think - than I had thought.

"Somatic" simply means bodily or of the body, on its own it doesn't suggest the mind or mental stresses. Of course, the word is frequently employed to do so, such as psychosomatic (ie mindbody), and some interpretations of functional somatic syndrome (ie functional bodily syndrome, as opposed to an organic bodily disease) and somatisation (eg to transfer into the body / interpret or experience as bodily etc).

 

[Sushi]

"In conclusion, CFS patients have unaltered autonomic responses to simple mental stress as compared to healthy control subjects"
Darn it.
I just missioned off to see a specialist about this today. He's booked me in for three days of testing (tilt-table on the NHS - I'm so excited!)

The tilt table test I did (they differ from doc to doc) involved some mental stressors. For instance they had you read a few sentences into a recorder and then measured all your responses when they played it back to you and asked you to read the same sentences out loud, but not synced to the recording you had just made. Course, I had wacky responses.

While a lot of the TTT test measures responses to stuff like gripping, blowing etc., a doc who is experienced realizes that there is mental stress in the various parts too--cause you can feel your wacky responses and they can be scary.

Esther, do you know if they are going to inject stuff into a vein first? And whether they are going to make you stand there till you pass out? It is good to know about all this ahead of time because you might not want to go through everything they want you to go through.

My doc at that time had POTS himself so he didn't inject you and stipulated that anytime you felt really uncomfortable you could stop the test. He did NOT want to take you to a faint, as he knew how hard that is on the body. Even this "compassionate" TTT took a week to recover from.

Don't want to put you off (the test gives great info in the hands of a good doc) but it is wise to know what they plan to do ahead and give your input.

Hope it goes well for you,
Sushi

 

[Dolphin]

I haven't read the study yet but it seems plausible that it was not demanding enough either in length and/or intensity.

Also, some tests are more important to others for the person doing it (i.e. some people might perhaps not push themselves that hard for a research test) - I relapsed after an exam in college (got a good result) (within a couple of hours my throat swelled up and I felt flu like from then on for weeks - a few days later a locum was called to the house and I had a high temperature - this was May/early June so not the normal time for such problems); the mathematics department were tough and didn't tell you how many questions to answer - you were marked out of the number of questions the best person did. I had done previous exams without fewer problems.
I'm no expert but maybe some sort of incentive to get people to push themselves in tests might be good e.g. financial rewards if they get a certain percentage correct or a certain number of questions done within the time.

 

[Esther12]

Don't want to put you off

*gulp*

I thought I just lay on a tilty table.

 

[Cort]

No problem, Cort. What are dolphins for.

That's right - such beautiful graceful and powerful creatures - we love to watch them work...

 

[Cort]

*gulp*

I thought I just lay on a tilty table.

Actually it depends on how they do it; they injected me with something and I mostly passed but I felt awful (they didn't measure that). My twin brother on the other hand felt just fine...

It is surprisingly stressful - just getting tilted up - and, of course, some people have a terrible time with it.....but when they faint they usually stop the test so that's good

that was probably not very reassuring


Good luck with it - please report back.


T

 

[Esther12]

that was probably not very reassuring

I suddenly feel more sympathetic for the Wessely anti-testing position!

 

[Dolphin]

Actually it depends on how they do it; they injected me with something and I mostly passed but I felt awful (they didn't measure that). My twin brother on the other hand felt just fine...

Didn't know you were a twin, Cort. Did you take part in the twin studies with Dedra Buchwald?

 

[Sushi]

I'm going to have to stay with relatives of my partner too, so will feel a bit awkward if I'm going to be even more of a burden than usual. Oh well. These shaming experiences are good for the soul!

I suggest that you take a "recovery pack" with you. I had to fast (they usually make you fast so you don't barf!) so I was dehydrated and had low blood sugar when they started. They offered me apple juice afterwards, but I needed much more. I had the kind of food and drink that helps restore me, with me, and I had to sit around for an hour eating drinking and stabilizing before I could leave.

Again, sorry to put you off, you may sail through, but it is good to be prepared!

Sushi

 

[Dolphin]

Esther12, if it's on the NHS, I reckon it won't be too fancy - most tilt table testing doesn't involve mental stressors from what I can make out. If there's a local group, they might be able to tell you.

 

[Esther12]

Ah well. Good to be pre-warned.