When singer Celine Dion recently announced that she was diagnosed with stiff person syndrome (SPS), it created an opportunity for many to learn about this rare autoimmune neurologic disorder that affects only one in a million people.
SPS makes torso and limb muscles progressively rigid and causes severe, painful muscle spasms.
While SPS is not fatal, muscle stiffness and spasms can cause loss of mobility, including difficulty walking, and falls. This makes performing everyday tasks challenging, which can greatly affect patients’ quality of life and can lead to agoraphobia, depression and anxiety.
What Causes SPS
Experts do not know what causes SPS but believe it could result from an autoimmune reaction that occurs when autoantibodies destroy central nervous system cells that control muscle movement.
Up to 80 percent of SPS patients have these autoantibodies, which attack glutamic acid decarboxylase (GAD), in their cerebrospinal fluid and blood. This enzyme converts glutamate into the neurotransmitter gamma-aminobutyric acid (GABA), which is important in slowing down the brain.
Some researchers theorize that low levels of GABA can lead to overactive nerves that cause muscles to become rigid and contract. Since GABA also regulates anxiety, low levels of this neurotransmitter may also contribute to anxiety in SPS patients.
More women than men are diagnosed with SPS. Our founder Dr. Yessar Hussain explains that disease usually impacts young to middle aged patients between 30 to 60 years of age. SPS is more common in cancer patients, and they often have more than one autoimmune disease. These can include:
- Pernicious anemia
- Myasthenia gravis
SPS is a spectrum disease; progression and severity vary from patient to patient. SPS symptoms include:
- The condition can impact just one area of the body or it can be widespread
- Inflexible, hard muscles in the abdomen, chest, back, legs or arms
- Muscle stiffness can fluctuate and often occurs alongside spasms
- Muscle spasms can last from seconds to hours
- Spasms can occur randomly or in response to stimuli like light, temperature, physical contact, noise and stress
Since the condition is so rare, doctors don’t see many SPS cases. In addition, more common disorders exist with similar symptoms. As a result, SPS can be misdiagnosed or unrecognized, and instances of the condition may be under reported.
Fortunately, tests and exams can be used to rule out other conditions like diabetes, Parkinson’s disease, fibromyalgia and multiple sclerosis. In addition to a physical exam, these tests can include blood and cerebrospinal fluid tests that can identify high levels of GAD antibodies and electromyography (EMG), which assesses muscle and nerve cell activity.
There is no cure for SPS. We help SPS patients return to everyday activities by treating symptoms, usually with muscle relaxants and pain management. Our ANC team also targets the underlying cause of the disease with immune modulating agents.
SPS patients can work to improve their mobility through physical, aqua and occupational therapy. Cognitive behavioral therapy can teach patients ways to cope with emotional stress that can trigger muscle spasms and skills to live with this chronic condition.
A clinical therapeutic trial may be another beneficial option for some SPS patients.