The Complex

Is ME/CFS/FM bigger than we think?  Does it consist of a complex of  disorders such as ME/CFS/FM/POTS/Autonomic Neuropathy/IBS/ (fill in the blank) that share similar types of onset, symptoms and some lab results. Let’s see how that question is shaking out.

Infections are the Most Common Trigger of POTS


Infections don’t just trigger ME/CFS; they also commonly trigger POTS, fibromyalgia and autoimmune disorders

The more you look, the more you find. We know infections are common triggers of chronic fatigue syndrome, autoimmune disorders, fibromyalgia, and autonomic neuropathy. Now a very large Johns Hopkins /New York Medical College study reveals that more cases of POTS are triggered by an infection (infection-45%, viral-31%, bacterial-14%) than by anything else (surgery or trauma – 26%) and puberty (22%). One wonders how many other chronic illnesses are triggered by infections.

The surgery connection is interesting given the discussion I recently had with a doctor associated with Daxor Corporation, a company that produces a semi-automated Blood Volume Analyzer, who noted the stress surgery often imposes on the cardiovascular system.

The fact that women tend to need more transfusions after surgery suggests they may have more problems maintaining blood volume than men. (It also suggests that blood volume is rarely checked prior to surgery.) One wonders if pre-surgical patients should be routinely asked if they have symptoms of orthostatic intolerance, and, if they do, have their blood volume levels checked.


The connections between ME/CFS, FM, POT and several autonomic nervous system disorders are growing….

The POTS and ME/CFS Complex

The same study found ME/CFS diagnoses were very common in POTS (33% of POTS patients), but that migraines are even more commonly found (45%). With a recent study finding a high prevalence of migraine in ME/CFS and all three disorders sharing problems with blood flow, the autonomic nervous system connection is growing ever more interesting.

ME/CFS was the second diagnosed disease but Ehlers-Danlos Syndrome (hypermobility), a much less well known disorder, was present in a surprisingly high (29%) percentage of patients. Gastrointestinal reflux, IBS, and sleep disorders were also commonly found. It is interesting that high rates of food intolerance were found in POTS, with dairy (44%) and wheat/gluten (29%) leading the list.

Very high rates of fatigue (70%), lightheadedness (60%), brain fog (52%), and gut problems (43%) rounded out a symptom picture very similar (high fatigue, brain fog, gut problems, etc.) and yet different (high lightheadedness, little pain, no PEM mentioned) than found in ME/CFS. One wonders how much post-exertional malaise lay buried under fatigue

The POTS, ME/CFS, FM, and Autonomic Neuropathy Complex

Another study of people with autonomic neuropathy (damage to the autonomic nerve fibers) found similar co-morbidities to those in POTS. They included chronic fatigue syndrome, migraines, fibromyalgia, gut problems and others. Several studies this year found high rates of small fiber neuropathy in fibromyalgia. If those studies are validated, expect the ME/CFS, FM, POTS, and Autoimmune Neuropathy connection to grow and grow. We expect to hear more from Dr. Sivieri and Dr. Teitelbaum on their experiences looking for and treating SFN in ME/CFS and FM patients by next year.

The Gut-Brain Connection

No less than 10-20% of the population suffers from ‘functional gastrointestinal disorders’ such as IBS, chronic unexplained nausea, ‘abdominal migraines ‘ (!) and functional dyspepsia. (Abdominal migraines are more commonly found in children, often run in families with migraines, are often preceded by an aura, and are accompanied by acute, severe abdominal pain, nausea, vomiting, paleness, and inability to eat.) In the absence of clear gut pathology, understanding these ‘extremely complex’ disorders has been difficult. But in the past 1-2 decades, research is pointing at the brain-gut connection, and the gut flora (gut microbiome).


A genetic predisposition to these ‘functional’ disorders is assumed.

The current belief is that genetic or epigenetic factors predispose a certain percentage of the population to coming down with a ‘functional disorder’. (Hopefully, the term ‘functional disorder’– which refers to a disorder that reduces functioning without laboratory evidence indicating why – will be retired at some point.)

It happens something like this: a first hit (infection, toxin – some sort of stressful event) that produces few symptoms occurs and the individual appears to recover, but the groundwork for disaster has been laid. Later, a second hit – an illness, stressful emotional event, etc. – triggers the occurrence of a ‘functional gastrointestinal disorder’, or in many cases a ‘functional disorder syndrome’ such as IBS plus ME/CFS, fibromyalgia, migraines, POTS, or others.

Some researchers believe a similar process – a series of infectious events that primed the system, so to speak, to collapse – commonly occurs in ME/CFS. Dr. Chia, in particular, has talked of a series of infections that get worse over time. Dr. Pridgen’s entrée into fibromyalgia involved watching his gut patients respond to his treatments only to relapse and then get worse with the advent of a stressful event. It was that pattern of relapse/improvement/bigger relapse/less improvement/even bigger relapse that led him to propose that a spreading viral infection causes fibromyalgia.

Several factors seem to prime the system to collapse in these gut disorders, including adverse early life events, alterations in the gut flora, and (get this!) glial pathways and sleep disturbances. Poor sleep, in particular, appears to set the stage for functional pain and fatigue disorders.

“The enteric nervous system represents a unique component of the autonomic nervous system”

Animal studies are beginning to reveal how this happens. Laboratory animals exposed to stress, inflammatory, or postinflammatory conditions undergo changes in their gut, secretory, and sensory nervous system pathways that result in long-term disruptions in gut functioning and heightened sensitivity to pain. Altered gut serotonin signaling and an as yet unidentified neuroactive factor both appear to play major roles in this ‘neural sensitization’ process. (An extract from the gut mucosa of IBS patients provokes unusual responses in healthy gut neurons, but the factor tweaking the neurons that has not yet been identified.) That neural sensitization that begins in the gut then spreads to the spinal cord and/or brain pathways.

The Insula is Back – Increased activity in the part of the brain that integrates the sensory inputs from the body, the insula, is showing up in all these disorders. Altered activity in the insula appears to be associated with increased pain levels and hyper-awareness of sensory signals coming from the gut. IBS patients also share with FM, ME/CFS and POTS heart rate variability and reduced vagal tone.

Whoops – Drug Induced Autonomic Nervous System Failure Puts Woman in Wheelchair

 This is an extraordinary drug interaction involving two relatively commonly used drugs leading to a devastating complication. Infections, concussion, injuries, and cancer treatments appear to be able to trigger a kind of long-lasting system reset of one form or another in chronic fatigue syndrome, fibromyalgia, POTS, autoimmune disorders, etc.


The wrong drug combination basically blew one persons autonomic nervous system to smithereens…She recovered completely after getting off one drug.

The case report below suggests drug combinations in susceptible individuals can essentially blow their autonomic nervous system to smithereens. If you had ME/CFS and then developed OI sometime after you started a new drug treatment, you might want to think about this woman’s case.

It all began for one 18-year-old Texas woman who showed up in a wheelchair at an Autonomic Clinic (Autonomic Function Clinic) with extremely low blood pressure upon standing. This woman was a mess; she’d been unfortunate enough to come down with leukemia as well as migraine, avascular necrosis, obsessive-compulsive disorder, anxiety, depression and increased weight.

She was taking no less than 10 prescription drugs (midodrine, fludrocortisone, fluvoxamine, desvenlafaxine, clonazepam, topiramate, drospirenone/ethinyl estradiol, tizanidine, zolpidem, and oxycodone.)

Upon standing her blood pressure fell from 118/70 to 50/33. She lasted about 2 minutes standing before fainting and going into convulsions. Once she hit the ground her blood pressure recovered quickly. Autonomic testing (the kind Wellpoint Insurance is no longer covering – see here) revealed ‘dense sympathetic autonomic failure’. Her initial diagnosis was autoimmune autonomic ganglionopathy.

The doctors noted, however, that fluvoxamine decreased tizanidine clearance, which suggested tizanidine might be rapidly increasing in her system. Even though tizanidine is not believed to affect the autonomic nervous system, they took her off it. Two weeks later she was shopping and exercising without symptoms. After standing for 10 minutes her blood pressure was the same as when she started.

The doctors conjectured that at very high levels tizanidine can indeed affect the autonomic nervous system. Add drug interactions to the list of stressors that can trigger dysautonomia. The takeaway point: watch your drugs closely and don’t even begin to think our understanding of what they do is complete. If you have autonomic nervous system problems, you might consider monitoring your symptoms over time. It appears that a portable autonomic nervous system monitoring system may be coming to your doctor’s office soon.

Being ‘Smart’ About Your Autonomic Health


The first mobile autonomic nervous system monitor may be coming to your doctors office soon

The Department of Biomedical Engineering at Vanderbilt University (no surprise, there) has built a ‘low-cost’ miniature device that interfaces with your smartphone (of course) to monitor your autonomic nervous system. It monitors your blood pressure, uses high-quality ECGs to monitor heart rate, stroke volume of your heart, ‘body impedance’, as well as fluid shifts when you stand, sit down, etc. It allows you to input your symptoms and maintain a diary. It can be programmed to detect fluid shifts and falls in critical blood pressure values that may precipitate a faint or fall, and sound an alarm urging you to sit down immediately. Hopefully, it will be coming to your online app store soon.





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