Testing identifies autonomic symptoms of Gulf War syndrome

[Altostrata]

Also seen in psychiatric drug withdrawal syndromes, autonomic problems are found through specialized testing to be associated with Gulf War syndrome.

 

http://www.medpagetoday.com/Neurology/GeneralNeurology/36113

 

Nerve Deficits May Drive Gulf War Syndrome

By Nancy Walsh, Staff Writer, MedPage Today

Published: November 26, 2012

• Dysfunction of the autonomic nervous system may underlie the symptoms experienced by veterans with Gulf War syndrome and its variant subtypes.
• Note that scores on several measures of autonomic function were significantly higher among cases, including secretomotor symptoms, sleep abnormalities, urinary symptoms, and upper gastrointestinal motility problems, consistent with dysfunction of both central and peripheral cholinergic function.

Dysfunction of the autonomic nervous system may underlie the myriad symptoms experienced by veterans with Gulf War syndrome and its variant subtypes, a case-control study suggested.

 

On the self-administered Autonomic Symptom Profile (ASP) questionnaire, the mean score for orthostatic intolerance among controls was 2.4 out of a maximum of 40, compared with a score of 22.2 among cases with the syndrome subtype in which confusion and ataxia predominate, according to Robert Haley, MD, of the University of Texas Southwestern Medical Center in Dallas, and colleagues.

 

For the Gulf War syndrome variant in which impaired cognition is the dominant symptom, the mean ASP score for orthostatic tolerance was 12.9, and for the variant characterized mainly by central neuropathic pain the mean score was 13.7 (P<0.001 for all), the researchers reported online in Archives of Neurology.

 

Moreover, the Composite Autonomic Severity Scores, which combine objective measures of autonomic deficits on a scale of zero to 10, also were higher overall in cases than in controls, again most notably with the confusion/ataxia variant (1.90 versus 0.71, P=0.045).

 

During the 2 decades since 700,000 members of the U.S. military were deployed to the Persian Gulf after Iraq's invasion of Kuwait, an estimated one-fourth have reported multiple chronic symptoms including pain, fatigue, diarrhea, sexual dysfunction, and cognitive abnormalities.

 

Hypotheses as to the cause of the illness have included neurotoxic exposures and stress, but few objective correlations such as laboratory or pathologic tests or biomarkers have been identified.

 

....

Haley and colleagues previously found evidence implicating central cholinergic parasympathetic dysfunction in a small group of veterans afflicted with the syndrome.

 

To further explore this possible underlying explanation for multiple seemingly unrelated symptoms, the researchers enrolled 66 cases and 31 controls, who were also military veterans but who had not been deployed in the Gulf War.

 

Scores on several domains of the ASP other than orthostatic intolerance also were significantly higher among cases, including secretomotor symptoms, sleep abnormalities, urinary symptoms, and upper gastrointestinal motility problems (P<0.001 for all).

 

Those domains related to cholinergic activity, and accounted for much of the difference between cases and controls (R2≥0.20).

 

In contrast, symptoms relating primarily to the adrenergic system, including vasomotor and pupillomotor symptoms, sexual dysfunction, and reflex syncope, explained less of the difference (R2<0.20), the researchers found.

 

"The pattern of autonomic symptoms and objective test findings points predominantly to dysfunction of both central and peripheral cholinergic functions, possibly from neurotoxic damage to cholinergic neurons or cholinergic receptors," explained Haley and colleagues.

 

In another objective test of autonomic function, which measures axonal sweat gland stimulation, reductions were seen in distal postganglionic function, with diminished sudomotor sweat production in the foot....

 

This reduction in sweat was less in the ankle and leg and was not present in the arm, "indicating nerve length-related damage to the peripheral autonomic nervous system affecting the distal small cholinergic sudomotor fibers," the authors observed.

 

Additional tests included investigations of circadian changes in parasympathetic tone using 24-hour electrocardiograms, in which the normal nocturnal increase in high-frequency heart rate variability was lacking in cases but not controls.

 

The confusion/ataxia variant group also had lower daytime high-frequency heart rate variability compared with controls, while the daytime variability was higher than controls in the neuropathic pain group.

 

A moderate inverse correlation was seen between nocturnal heart rate variability and scores on objective autonomic tests (r = −0.41, P<0.001), while a weak correlation was seen for daytime variability (r = −0.22, P=0.04).

 

This blunting of the expected nocturnal rise in high-frequency heart rate variability "clearly demonstrated" impairment of the autonomic nervous system, the researchers stated.

"These results confirm dysfunction among Gulf War veterans of both central control of parasympathetic function and peripheral cholinergic autonomic nerves, further implicating underlying damage to the cholinergic components of the central and peripheral nervous system," they concluded.

 

In his editorial, Freeman argued in favor of stress as a major underlying factor in these disturbances of autonomic function, pointing to animal models showing alterations in nerve circuitry, catecholamine and serotonergic function, and impairments of the hypothalamic-pituitary-adrenal axis.

 

Similar findings have been seen in human stress-induced hypoglycemia.

 

"Taken together, these preclinical and clinical data demonstrate a wide array of objective structural, physiological, and clinical manifestations of stress," Freeman wrote.

 

....

The study was funded by the Department of Veterans Affairs, the U.S. Army Medical Research and Materiel Command, and NIH.

 

The lead author has received an honorarium from Targeted Medical Pharma for reviewing a new drug application for a medication to treat fatigue.

 

Primary source: Archives of Neurology

Source reference:

Haley R, et al "Cholinergic autonomic dysfunction in veterans with Gulf War illness: confirmation in a population-based sample" Arch Neurol 2012; DOI: 10.1001/jamaneurol.2013.596.

 

Additional source: Archives of Neurology

Source reference:

Freeman R "Objective evidence of autonomic dysfunction and the role of stress in the Gulf War syndrome" Arch Neurol 2012; DOI: 10.1001/jamaneurol.2013.1494.

[Barbarannamated]

Very interesting. Are the subtypes identified similar to any patterns you've noticed in withdrawal, Alto?

 

Quick heads-up about the company sponsoring the study - prescription medical foods to provide amino acids to balance neurotransmitters.

http://www.tmedpharma.com/targeted-cellular-technology.php

[Altostrata]

Many of the above autonomic symptoms seem common in withdrawal syndrome:

 

- secretomotor symptoms (gastrointestinal)

- sleep abnormalities

- upper gastrointestinal motility problems

- orthostatic intolerance

- central neuropathic pain

- pain

- fatigue

- diarrhea

- sexual dysfunction

- cognitive abnormalities

 

most of the dysautonomia catalog....

 

Thanks for looking at the sponsor. Maybe they'll try to sell fish oil and magnesium at vastly inflated prices to the VA.

[starlitegirlx]

Thanks for looking at the sponsor. Maybe they'll try to sell fish oil and magnesium at vastly inflated prices to the VA.

 

Sad but true. When will people stop trying to profit off the suffering of others, particularly with crap products that will likely be inferior standards.

[Jemima]

When will people stop trying to profit off the suffering of others, particularly with crap products that will likely be inferior standards.

 

When you-know-where freezes over. There's a really unfortunate delusion in the USA and many other developed countries that $$$ = happiness and security, and never mind you had to kill or maim a bunch of people to get rich.

[Jemima]

Lots of military people are polydrugged to see them through the stress of combat. I wonder if military personnel who were put on psychotropic drugs were screened out or if these results include people who may very well be in antidepressant and other types of withdrawal in addition to the PTSD?