HSPs and Fibromyalgia, Chronic Fatigue Syndrome, and Other Illnesses Perhaps Related to “Central Sensitization”

Originally published in Comfort Zone Newsletter: May 2012

There has been a flurry of discussion on the internet about a link between high sensitivity and fibromyalgia. Fibromyalgia, as most of you know, causes widespread, lasting pain in the muscles and skeleton, sometimes including sensitivity to the slightest pressure. Of course with pain like that, it also often leads to fatigue, sleep loss, and depression. Why are people finding such a strong link between high sensitivity and fibromyalgia? Because some HSPs have it, although obviously many other HSPs do not. Where is the link to sensitivity?

Some New, Helpful Terms

Fibromyalgia and other illnesses have in common something Muhammad Yunus of the University of Illinois School of Medicine has called “central sensitization” (CS), which refers to an unusual sensitivity to pain occurring throughout the central nervous system. Among those with CS, some, but not all, people develop “central sensitivity syndrome (CSS).*

CSS is the common factor in a long list of diseases that have long been dismissed by some doctors as psychosomatic or “all in the head” because of a lack of an easily identified structural pathology. Yunus is seeking to correct that error by adding the idea of “functional pathology” to the traditional way of looking at an illness as some damage you can see, a “structural” problem. The diseases Yunus is looking at include fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, tension-type headache, migraine headache, temporomandibular disorders, myofascial pain syndrome, “restless leg syndrome,” multiple chemical sensitivity syndrome, female urethral syndrome and interstitial cystitis, severe menstrual pain and premenstrual syndrome, posttraumatic stress syndrome, some chronic neck and back pain, and some depression.

Again, not everyone with CS has one of these disorders, and some people with these CSS disorders develop CS only after the disease is present (and CS is not the same as fibromyalgia). That is, sometimes the disease itself leaves the body more sensitive to pain. Nor does CSS fully describe these other disorders, obviously. Each is unique in many ways. But Yunus has found hundreds of studies linking them to CS and CSS.

One value of identifying central sensitization (CS), according to Yunus, is that it lifts all of these disorders out of the dualistic “in the body” or “in the head” mess because CS represents afunctional pathology. That is, the nervous systems with CS are functioning in a way that causes patients to suffer, often disabling them, and this problem of pain is not seen in the majority of people (sound familiar?). That the problem is true pain sensitivity, not an emotional problem, can now be said confidently because there is new physiological measure of the degree of pain occurring that does not depend on verbal report (which might be affected by emotional problems). Using this measure, it is clear that sensitization to pain (CS) is stronger in some people than others, and in most of those having one of the illnesses he lists as related to CSS.

The Myriad Causes of Central Sensitization

Research suggests, according to Yunus, that CS has a wide variety of causes: Genetics (especially those genetic variations affecting neurotransmitters), poor sleep, infections, physical trauma, childhood or neonatal trauma, environmental irritants (noise, toxins, etc.), autonomic nervous system disorders, and probably other factors, not yet known, all can (but not always) create a “hyperexcitability” of neurons (nerves), and this in turn can (but not always) result in CS. CS is often (but not always) associated with central sensitivity syndromes (CSS). However, again, these disorders are all quite different in a number of ways, and manifest differently in each patient, so CS and CSS are simply broad concepts about some commonalities that may be useful for doctors trying to understand these disorders, especially those doctors who up to now have been skeptical or dismissive of these real illnesses.

(Having met some of these doctors–haven’t we all–I notice that most of them imbibed their skepticism during their medical training, in the past a rather pitiless environment; most are hyper masculine, that is tough and aggressive, if not always male; not HSPs, so when they encounter HSPs they can’t imagine the HSP’s subjective experience; have the cultural prejudice that to be sensitive is to be weak and weakness can be overcome if the person really wants to do it, but weak people often prefer to be sick; and as they age and face pain and mortality themselves, and meet some HSPs along the way, they usually change their tune.)

CS, Fibromyalgia, and HSPs

Central sensitization or CS, as Yunus defines it, is only about sensitivity to pain. Sensitivity to pain is on the HSP Scale because it is a feature of the larger trait we know as high sensitivity (HS) or sensory processing sensitivity. I suspect that many of those measuring high on the physiological measure of pain Yunus describes will also score high on the HSP Scale. But not every HSP is sensitive to pain, and not every person sensitized to pain in the CS sense is an HSP.

The only way that HS could contribute directly to central sensitization or CS is through genetics. There are quite a few genes implicated in CS, and two of these, involving dopamine and serotonin, are also common to HSPs. But HSPs are more prone to develop physical or emotional problems only when they are–that familiar list again–under stress, lack sleep, have had physical or psychological trauma as children or adults, been depleted by infection, and so forth. Probably at those times their sensitivity to pain increases also. All of this suggests that HS and some CS may be similar, in that both begin with a genetic susceptibility to both good and bad environments, as I have said over and over.**

Getting It Right about Us

The problem is that the discussion of CS is limited to pain and vulnerability, with no thought yet about why the genetic aspect of CS has remained in the gene pool, probably in about 20% of humans and over 100 other species!

What matters most to me in all of this is that we all remember that not many HSPs have or will ever have fibromyalgia, chronic fatigue, or any other serious central sensitivity syndrome (CSS) problem. The less serious ones, well, that seems more likely, but usually only when we get stressed and have those hyperexcited neurons. (By the way, another related theory has it that Yunus’ list of disorders are actually caused by adrenal failure, when the hyperexcited neurons finally wear out.) But again, CSS disorders are not the main feature of being highly sensitive and not true of every HSP. Sensitivity to pain or to stimuli in general is also not the main feature. After all, many HSPs wear glasses and hearing aids! It is a much broader survival strategy found, again, in over 100 species, but always in a minority. These individuals take the approach of surviving (in an evolutionary sense) by processing everything more thoroughly than others do before acting. Brain research indicates that they respond more to their experiences, consciously or unconsciously, and see more subtleties (they are not just being bothered by strong stimuli). They also have stronger emotional reactions, which is part of what motivates them to process more deeply. In many ways, from sensitivity to caffeine and pain, to sensitivity to beautiful music and others’ moods, HSPs are more sensitive or “responsive,” as some biologists are calling it.

You can find many people with fibromyalgia and other CSS disorders who are definitely not HSPs, even if they have CS and therefore in that sense seem to be HSPs. Thus even to say that fibromyalgia or other problems on the list are a product of the interaction of being an HSP and stress or trauma would not always be true.

Above all, we don’t want to give the impression, or have others give or get it, that being highly sensitive creates a vulnerability to fibromyalgia or anything else in every HSP. To say that would not only be untrue, but interfere with our larger project of getting us appreciated and empowered–that is, having greater influence in the world.

Not All HSPs Are at Risk, but Some Are

It is clear, however, that for HSPs to avoid being susceptible to illnesses such as these, they do need to live in a way that helps them avoid becoming over stimulated and stressed. If you are living in a non-HSP world, however, you will often get messed up, of course, no matter how hard you try to avoid it. So, as you well know, you also need ways to manage during stressful times and after. A daily meditation practice is helpful, one that effortlessly develops a quiet, restful, state of mind, one that you can return to during stressful periods. Plus you need plenty of sleep, time off each week and year, and so forth. You need to cut down on your activities during stressful times by learning to say no, to others and yourself, and to find your pleasure in each moment. You need exercise and a healthy diet. It’s all in The Highly Sensitive Person, Ted Zeff’s Survival Guide, and in these blog posts.

If you already have a CSS illness, improving your life will improve your health, according to many reputable books by good doctors. Please be careful, however, of cures that focus on only one factor, drain your pocketbook, or make you more socially isolated (through a too-restrictive diet, for example) than you already may be due to your illness. So seek social support from others with the same disease, especially those who are HSPs like yourself and who offer sensible suggestions based on experience.

I know that some people will read this article and conclude from a few things that I am saying something like fibromyalgia is “all in the head.” If you think that, please read this again! I know many people with these CSS illnesses who have been terribly hurt by doctors who have implied that, and as a result are very sensitive to anything implying that their illness is not real. But to ignore the fact that emotions and innate emotional reactivity are bodily events that have their influence is just as unhelpful. When emotional factors do play a role, working on these can be another way to health. However, once the nervous system is depleted, it is rarely the only way.

All in all, it seems wonderful that these internet discussions of fibromyalgia and being highly sensitive are occurring. From what is being said, it clearly is a huge help to understand this piece of it and to meet others through various websites who are highly sensitive in the same way. Here’s to the discovery of more effective and more sensitive treatments to these terrible, painful, life-limiting illnesses.

* You can learn more about CSS and Muhammad Yunus’ work here and here. The first is from a scientific journal, but not too hard to understand. The second is for the general public.

** Appreciating Sensitivity: We’re Simply More Responsive, Comfort Zone November 2009.

A Few “Happy” Things Regarding Depression, Comfort Zone February 2010.