Electroencephalogram characteristics in patients with chronic fatigue syndrome

[Kati]

https://www.dovepress.com/electroen...th-chronic-fatigue--peer-reviewed-article-NDT

Open access. Used CDC criteria.

Electroencephalogram characteristics in patients with chronic fatigue syndrome
Tong Wu,1 Xianghua Qi,1 Yuan Su,2 Jing Teng,1 Xiangqing Xu1

1Internal Medicine-Neurology, Shandong Provincial Traditional Chinese Medical Hospital, 2School of Mathematic and Quantitative Economics, Shandong University of Finance and Economics, Jinan, People’s Republic of China

Abstract

Objective:
To explore the electroencephalogram (EEG) characteristics in patients with chronic fatigue syndrome (CFS) using brain electrical activity mapping (BEAM) and EEG nonlinear dynamical analysis.

Methods:
Forty-seven outpatients were selected over a 3-month period and divided into an observation group (24 outpatients) and a control group (23 outpatients) by using the non-probability sampling method. All the patients were given a routine EEG. The BEAM and the correlation dimension changes were analyzed to characterize the EEG features.

Results:
1) BEAM results indicated that the energy values of δ, θ, and α1 waves significantly increased in the observation group, compared with the control group (P<0.05, P<0.01, respectively), which suggests that the brain electrical activities in CFS patients were significantly reduced and stayed in an inhibitory state;

2) the increase of δ, θ, and α1 energy values in the right frontal and left occipital regions was more significant than other encephalic regions in CFS patients, indicating the region-specific encephalic distribution;

3) the correlation dimension in the observation group was significantly lower than the control group, suggesting decreased EEG complexity in CFS patients.

Conclusion: The spontaneous brain electrical activities in CFS patients were significantly reduced. The abnormal changes in the cerebral functions were localized at the right frontal and left occipital regions in CFS patients

 

[Kati]

i posted when I saw the abstract. i am reading the beginning and their introduction is not sitting too well with me so far:

One of the major causes of CFS is mental stress. In addition, smoking, excessive drinking, unhealthy diet and lifestyle, as well as lack of exercise and psycho- logical counseling, may aggravate CFS progression

 

[Never Give Up]

Ick.

 

[Effi]

i am reading the beginning and their introduction is not sitting too well with me so far:

does this take away from their conclusion though? (Not sure how reliable this kind of testing is - if anyone knows more I'd love to hear more)

Conclusion: The spontaneous brain electrical activities in CFS patients were significantly reduced. The abnormal changes in the cerebral functions were localized at the right frontal and left occipital regions in CFS patients

 

[sdmcvicar]

Well, at first glance, the data looks very clean. Several alarm flags though:

1) I noticed that in Table 3 that they used

"A comparison of 14 lead results in the two groups"

Depending on if they mean 14 from each group, or 14 total, that means they excluded 1/3 or 2/3 of their data, respectively. Lead could mean that they gave the most consistent data. I wish I could discard a third of my own data, it would turn a lot of not significant comparisons into highly significant results.

2) This is an open access journal I've never heard of. This potentially means a minimal peer review process or that the authors couldn't publish in a higher impact factor journal.

3) In addition to their 24 CFS patients and 23 controls,

"One hundred and three people dropped out of the study during the process."

I'm not sure if this is normal in their area, but that seems pretty high for people who enrolled in the study, since EEG is non-invasive.

4) Minimal references, many of which are guidelines for classification or method, and CFS-specific papers are ones I don't recognize.

As always, it would be good to see this replicated in a larger study by a reputable lab. It would also be nice if they tested an intervention (eg provigil) in the control and CFS groups to see if they return to near normal for a brief period.

 

[jimells]

"A comparison of 14 lead results in the two groups"

Depending on if they mean 14 from each group, or 14 total, that means they excluded 1/3 or 2/3 of their data, respectively. Lead could mean that they gave the most consistent data. I wish I could discard a third of my own data, it would turn a lot of not significant comparisons into highly significant results.

This is just a guess, but perhaps "14 leads" means "14 electrodes"?

 

[Effi]

thanks @sdmcvicar

 

[sdmcvicar]

This is just a guess, but perhaps "14 leads" means "14 electrodes"?

You are absolutely right. Missed that the header within the table was labeled as Lead rather than Electrode, and that there are 14 of them listed. Thank you. This increases my confidence in the results substantially.

It would also be nice if they tested an intervention (eg provigil) in the control and CFS groups to see if they return to near normal for a brief period.

Having thought about this a little more, it would also be interesting to see effect (if any) of hyperventilation (hyper-oxygenation of the blood) on the results in the CFS cohort. Not sure how common this is, but when I was initially being assessed as a teen in Canada, they used EEG to rule out epilepsy as a cause of my symptoms. As part of that test, they had me breathe as rapidly and deeply as I could until I started to shake and started having difficulty coordinating the rhythm of breathing. I recall being as lucid as I'd been prior to my flu-like symptom onset (no trace of brain fog) for roughly an hour after that.

I fully realize that this is anecdotal, but hyperoxygenation of the blood might offset the reduced blood flow and brain activity, characterized in multiple journal articles as a symptom of CFS, for a brief period of time. It's not viable as a long term intervention (I can't imagine starting off my day by hyperventilating until I lose coordination, or taking 8-9 hits of oxygen to get through a workday), but it might help characterize the brain fog in a qualitative fashion.

Of course, this could all be rambling resulting from 4 hours sleep plus the caffeine equivalent of 4 cups of coffee so far this morning.

 

[jimells]

I fully realize that this is anecdotal, but hyperoxygenation of the blood might offset the reduced blood flow and brain activity, characterized in multiple journal articles as a symptom of CFS, for a brief period of time.

Is it really possible to "hyperoxygenate" the blood? How can red blood cells be more than 100% saturated with oxygen? I readily admit ignorance about this stuff. My impression is the primary effect of hyperventilation is a reduction on blood carbon dioxide levels, which can cause lots of bad effects:

If excess ventilation cannot be compensated metabolically, it will lead to a rise in blood pH. This rise in blood pH is known as respiratory alkalosis. When hyperventilation leads to respiratory alkalosis, it may cause a number of physical symptoms: dizziness, tingling in the lips, hands or feet, headache, weakness, fainting and seizures. In extreme cases it can cause carpopedal spasms (flapping and contraction of the hands and feet).

If carbon dioxide levels are high, the body assumes that oxygen levels are low, and accordingly, the brain's blood vessels dilate to assure sufficient blood flow and supply of oxygen. Conversely, low carbon dioxide levels cause the brain's blood vessels to constrict, resulting in reduced blood flow to the brain and lightheadedness.

Hyperventilation doesn't sound like a very good idea for us.

 

[sdmcvicar]

Is it really possible to "hyperoxygenate" the blood? How can red blood cells be more than 100% saturated with oxygen?

Normal resting blood saturation is something like 96-99%. Hyperventilation or 100% O2 inhalation can increase that value to 100%. 1-4% doesn't sound like much, but below 90% is considered hypoxia requiring medical intervention, so the differences can be pretty substantial in terms of resulting cognitive or physical function.

It's really hyperoxygenation of the brain tissue that results in increased cognitive function. This has been shown to boost performance on cognitive tests taken shortly after administration of 100% oxygen in both adolescents and the aged. If your blood is constantly saturated with oxygen, more is delivered to the tissues, which are not always near saturation. An example of poorly oxygen saturated tissue would be muscles during an anaerobic exercise while weight lifting. There, the cells can't metabolize glucose efficiently because there's not enough oxygen to "burn" it, so they have to switch to a much less energy efficient pathway that causes lactic acid buildup and muscle fatigue.

Hyperventilation doesn't sound like a very good idea for us.

Undoubtedly. Again, it's used as a stress test to diagnose epilepsy, as the effects you listed can cause onset or increase severity of an epileptic episode.

 

[alex3619]

Oxygen can indeed be beyond 100%. 100% would be 100% of a reference standard. Both blood cells and plasma can carry oxygen over that but the effect is marginal. Slow deep breaths are more likely to help than rapid breathing. What is not clear is that this will help, though some get benefit from oxygen therapy.

This study seems to be some people using their pet method, and CFS is just a test case. They probably do not know the CFS literature well.

 

[sdmcvicar]

@alex3619, you're probably correct about the reason for the study. As I'd mentioned before, I don't think much of it as an intervention for CFS/ME.

I'm trying to tie some disparate threads of research together as. It, in general, has lead me some pretty outlandish theories, but it's occasionally worked for me in other areas of research. My (overcaffeinated, sleep-deprived) thoughts went something like this:

1. There have been a number of studies describing brain abnormalities in CFS patients as compared to healthy adult controls, such as reduced blood flow, altered brain activation by fMRI, and now this EEG study.

2. Some of these results have been put forth as correlating with the brain fog severity.

3. My understanding (possibly flawed) is that healthy adults generally display minimal changes in cognitive tests after hyperoxygenation, but that patient populations displaying cognitive decline can show marked but transient improvements with the same treatment.

4. My own experience (n=1) leads me to the question: Does hyperoxygenation transiently improve cognitive function in a subset of CFS patients?

5. If so, would hyperoxygenation also shift the energy levels observed by this "BEAM" EEG method from the inhibited state observed in the CFS cohort toward values seen in the healthy controls, while the controls remain relatively unaffected after hyperoxygenation.

6. If so, does this provide additional, quantitative evidence of a physiological impairment in the brain that correlates to a well-characterized symptom of CFS/ME?

 

[JAH]

I had a 48 HR EEG this week to rule out seizure, and it was normal.

 

[jimells]

I had a 48 HR EEG this week to rule out seizure, and it was normal.

Was it hard to sleep with all those wires stuck to your head?

 

[JAH]

Hey jimellis - the test was brutal because I had to share a room the first night and got no sleep. Second night better, (semi private) but with CFS, it's just very tough, because I feel so miserable when I can't sleep and rest. So many people coming in and out. So - wires weren't the problem, noise and light were.

My doc was wrong, not frontal lobe seizures, they did some other tests to determine why I'm having these "events", I might have porphyria.

I see Dr. Montoya, and will ask him to also read the EEG, to see if there is any CFS pattern there. These were epilepsy docs I saw this week. Still recovering...haven't gotten out of bed since.

 

[jimells]

I might have porphyria.

The porphyrias are a group of rare diseases in which chemical substances called porphyrins accumulate with high metabolism. The body requires porphyrins to produce heme, which carries oxygen in the blood.

But in the porphyrias, there is a deficiency (inherited or acquired) of the enzymes that transform the various porphyrins into others, leading to abnormally high levels of one or more of these substances. This manifests with neurological symptoms or skin problems, or occasionally both.

Uggh. Sounds horrible. It's a good thing you have real doctors on your side. In the UK they'd just call it "psychogenic non-epileptic seizures" and tell you to do CBT.

 

[alex3619]

I had a 48 HR EEG this week to rule out seizure, and it was normal.

qEEG or BEAM as the call it is a different technology, though related.

 

[JAH]

qEEG or BEAM as the call it is a different technology, though related.

Thanks for the clarification