Sympathetic nervous system dysfunction in fibromyalgia, CFS, IBS, and interstitial cystitis...

[Bob]

Sympathetic nervous system dysfunction in fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis: a review of case-control studies.
Martínez-Martínez LA, Mora T, Vargas A, Fuentes-Iniestra M, Martínez-Lavín M.
J Clin Rheumatol. 20(3):146-50.
2014 Apr
doi: 10.1097/RHU.0000000000000089.
http://www.ncbi.nlm.nih.gov/pubmed/24662556/

Abstract
BACKGROUND:
Fibromyalgia often coexists and overlaps with other syndromes such as chronic fatigue, irritable bowel syndrome, and interstitial cystitis. Chronic stress has been implicated in the pathogenesis of these illnesses. The sympathetic nervous system is a key element of the stress response system. Sympathetic dysfunction has been reported in these syndromes, raising the possibility that such dysautonomia could be their common clustering underlying pathogenesis.

OBJECTIVE:
The objective of this study was to carry out a review of all published comparative case-control studies investigating sympathetic nervous system performance in fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis.

METHODS:
Online databases PubMed and EMBASE were accessed using the following key words: autonomic (OR) sympathetic (AND) fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis. All entries up to December 10th 2012 were reviewed by 2 independent investigators searching for case-control studies in humans. The Method for Evaluating Research and Guidelines Evidence adapted to the Scottish Intercollegiate Guidelines Network was used to rank the level of evidence contained in the selected articles.

RESULTS:
A total of 196 articles are included in this review. The most often used methods to assess sympathetic functionality were heart rate variability analysis, sympathetic skin response, tilt table testing, and genetic studies. The majority of studies (65%) described sympathetic nervous system predominance in these overlapping syndromes. In contrast, 7% of the studies found parasympathetic predominance.

CONCLUSIONS:
This review demonstrates that sympathetic nervous system predominance is common in fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and interstitial cystitis. This concordance raises the possibility that sympathetic dysfunction could be their common underlying pathogenesis that brings on overlapping clinical features. The recognition of sympathetic predominance in these 4 syndromes may have potential clinical implications. It may be worth exploring the use of nonpharmacological measures as well as drug therapies aimed to regain autonomic balance.

 

[barbc56]

For a long time after being diagnosed, I didn't realise that IBS is neurological. I think it has to do with the brain signals that control the motility of the bowel. It was actually my PCP who told me this.

Barb

 

[anciendaze]

Barb, I hate to tell you and your PCP, but patients who have had the vagus nerve cut before it reaches the stomach continue to digest food and have bowel movements. The nerves controlling the process have been called a second brain.

 

[Bob]

Barb, I hate to tell you and your PCP, but patients who have had the vagus nerve cut before it reaches the stomach continue to digest food and have bowel movements. The nerves controlling the process have been called a second brain.

Can it not be a neurological condition, if the nervous system is affected other than the brain?

 

[Bob]

For a long time after being diagnosed, I didn't realise that IBS is neurological. I think it has to do with the brain signals that control the motility of the bowel. It was actually my PCP who told me this.

It's interesting. I've always thought of IBS as being an inflammatory illness, but there are probably different types of IBS.

 

[barbc56]

I do have some inflammation but not a lot.

I wonder if there are different types? I need to look this up as it sounds plausible.

Barb

ETA I wonder if the motility issues cause inflamation and would IBS-C or IBS-D make a difference?

 

[alex3619]

Barb, I hate to tell you and your PCP, but patients who have had the vagus nerve cut before it reaches the stomach continue to digest food and have bowel movements. The nerves controlling the process have been called a second brain.

This is correct but misses the point. What happens to IBS patients whose vagus nerve has been cut? I don't know that we have an answer to that.

The vagus nerve connects to a second system of control. If one system of control is working, and the other dysfunctional, what happens?

 

[WillowJ]

The recognition of sympathetic predominance in these 4 syndromes may have potential clinical implications. It may be worth exploring the use of nonpharmacological measures as well as drug therapies aimed to regain autonomic balance.

Sounds like an advert for Gupta programme/CBT/LP, & similar, with maybe some medication considered as a concession to the biomedical crowd.

 

[Cheesus]

Sounds like an advert for Gupta programme/CBT/LP, & similar, with maybe some medication considered as a concession to the biomedical crowd.

I'm actually a big fan of Gupta. It has really helped me to get rid of the horrible wired but tired feelings, other nervous system symptoms such as shaking and formication, and I am now a much more relaxed and happy person than I was even before I got ME. Ashok guarantees you can retrain the amygdala, not that you can recover from ME. The second part, however, does come for a number of people. I think it is an entirely valid part of a comprehensive treatment strategy. This research helps to explain why.

 

[anciendaze]

This is correct but misses the point. What happens to IBS patients whose vagus nerve has been cut? I don't know that we have an answer to that.

The vagus nerve connects to a second system of control. If one system of control is working, and the other dysfunctional, what happens?

The flaw I'm pointing out is that looking in the brain may not help if the neurological damage is elsewhere, nor will any therapy based on conscious control.

 

[alex3619]

The flaw I'm pointing out is that looking in the brain may not help if the neurological damage is elsewhere, nor will any therapy based on conscious control.

Which I agree with.

 

[N.A.Wright]

For a long time after being diagnosed, I didn't realise that IBS is neurological. I think it has to do with the brain signals that control the motility of the bowel. It was actually my PCP who told me this.

Barb

IBS appears to have multiple causes - one recent paper suggests impaired motility in 2% of patients is genetically mediated http://www.sciencedirect.com/science/article/pii/S0016508514002972 :

Diarrhea-predominant IBS (IBS-D) was the most prevalent form of IBS in the overall study population (25%). However, a greater percentage of individuals with SCN5A mutations had constipation-predominant IBS (IBS-C, 31%) than IBS-D (10%, P<.05). Electrophysiologic analysis showed that 10/13 detected mutations disrupted NaV1.5 function (9 reduced and 1 increased function); p.A997T-NaV1.5 had the greatest effect in reducing NaV1.5 function. Incubation of cells that expressed this variant with mexiletine restored their sodium current; administration of mexiletine to 1 carrier of this mutation (who had IBS-C) normalized their bowel habits. In the GWAS and 4 replicated studies, the SCN5A locus was strongly associated with IBS.
Conclusions
About 2% of patients with IBS carry mutations in SCN5A. Most of these are loss-of-function mutations that disrupt NaV1.5 channel function. These findings provide a new pathogenic mechanism for IBS and possible treatment options.

 

[barbc56]

@N.A.Wright

Thanks that's interesting to know.

Barb