I’ll start this article, like many others, by mentioning that although I’m convinced I know everything about everything because I minored in biology in college, I’m really not a doctor. I’m actually a patient– I was diagnosed with Ehlers-Danlos syndrome a few years ago, when I was about 20 years old. While my symptoms are at the mild end of the EDS spectrum, it’s changed the way I think about my body, my health, and symptoms I waved off as “not a big deal” over the past few years.
What is Ehlers-Danlos Syndrome?
Ehlers-Danlos syndrome (EDS) is a rare (or perhaps just under-diagnosed) connective tissue disorder caused by a genetic mutation. There are many different types of EDS, and characteristics vary between sub-types. The most well-known symptoms include joint hypermobility, skin elasticity, and easy bruising. However, since connective tissue acts as a type of “glue” throughout the body, any and every organ system can be affected. EDS has a high co-morbidity with dysautonomia (dysfunction of the autonomic nervous system), particularly a subtype called postural orthostatic tachycardia syndrome (POTS). POTS causes a rapid heartbeat upon standing up, and may lead to fainting among other symptoms. To read more about EDS click here, and to read more about POTS, click here.
EDS and Anxiety
Anxiety runs rampant among people with Ehlers-Danlos syndrome. According to a page on ehlers-danlos.com, “In one study 70% of hypermobile patients had some type of anxiety disorder, compared to 22% in the control group.”
Recently, I’ve been thinking a lot about this: while I knew that there was a clear relationship between EDS and anxiety, I didn’t understand what the connection was.
I could think of a lot of possibilities: Maybe it was genetic and had to do with the role of connective tissue in the brain. Maybe the rapid heartbeats caused by EDS created anxiety because it mimics the physical sensation of panic. Maybe there was something about the lived experience of an EDS patient, especially an undiagnosed one, which caused anxiety. Many patients with strange, seemingly unconnected symptoms are told that they’re experiencing hypochondria before they receive a diagnosis. Plus, if you live with mobility restraints and chronic pain, that can be isolating and stressful on its own.
I did a little digging online, and although researchers acknowledge there’s a link, there really isn’t a strong consensus on the “why.” However, I did find information from people asking the same question as I was, and coming up with some possible answers.
Genetic Risk and Other Biological Hypotheses
The genetic link is not well-explored, but many believe that it does play a part. Both conditions are very heritable, which suggests a connections.
Although one study found a duplication of chromosome 25 in patients with hypermobile EDS and anxiety disorders, further studies could not replicate this.
Ehlers-danlos.com explained, “Proposed mechanisms include structural differences in emotional-regulating parts of the brain and a link between anxiety disorders and poor control of automatic bodily functions.”
Researchers have even found that there is a difference in the volume of amygdalas (a part of the brain which plays a central role in processing emotions like fear) in people with and without joint hypermobility. This emotional-processing difference may play a role in the anxiety patients experience.
Another hypothesis questions if the correlation between EDS and autonomic nervous system dysfunction plays a role. Patients with hypermobile EDS have increased interoception (which means they experience more signaling for internal body sensations, such as hunger). Since the mind and body are, of course, intimately connected, this increase in visceral feelings can influence a person’s thoughts and emotions. A page on MD Edge Psychiatry points out that “atypical body awareness is a feature of multiple disorders, including anxiety, depression, and JHS/hEDS.”
Hypermobile EDS patients also have increased environmental perception (exteroception), pain perception (nocioception), and somatosensory amplification. When the body overreacts to sensory stimuli, it leads to heart rate, blood pressure, gastrointestinal and respiratory changes. It also, in turn, raises adrenaline in the body, which makes a patient jittery, anxious, and exhausted. Even stimuli other people may see as minor, like bright lights, can trigger a raised response in patients.
There are some controversies. Some have brought up the idea that patients with EDS and dysautonomia may have actually been misdiagnosed with anxiety disorders, since the symptoms, such as raised heartbeat, have some overlap. Others point out that patients with chronic pain and mobility limitations have higher rates of anxiety and depression, whether they have hypermobile EDS or not, suggesting that it’s a result of living with a chronic and painful illness.
More Research Needed
Although there are different hypotheses out there, there isn’t enough research to definitively trace the anxiety that EDS patients experience to one cause. Many factors may play a role, but it’s hard to know how to treat it if doctors don’t understand where the anxiety comes from. Once the medical community is better informed, more effective therapeutic strategies may come about.
In the mean time, the EDS community waits– anxiously.
