Canadian superstar Céline Dion's Instagram announcement that she has been diagnosed with stiff person syndrome is sparking questions about the rare and widely unknown disease.
The condition is a "neurological disorder with features of an autoimmune disease," according to the National Institute of Neurological Disorders and Stroke in the U.S.
The name doesn't do justice to the pain and life-changing symptoms the syndrome causes, said Tara Zier, founder of the Stiff Person Syndrome Research Foundation.
"A lot of people have challenges with mobility. Many have assisted devices for mobility, walkers, wheelchairs. Some people are bedridden," she said.
Zier started the foundation based in Bethesda, Md., in 2019 after debilitating symptoms forced her to leave her practice as a dentist and she was misdiagnosed for years.
How many people get stiff person syndrome?
About one or two people in a million are affected, according to the Stiff Person Syndrome Center at Johns Hopkins Medicine.
Although that's the rate that is generally reported, researchers don't know for sure, said Dr. Marinos Dalakas, director of the neuromuscular division at the Thomas Jefferson School of Medicine in Philadelphia.
The number of cases involving the rare disease could be higher because people are so often misdiagnosed, said Dalakas, who is also a member of the medical advisory board for The Stiff Person Syndrome Research Foundation.
Common misdiagnoses include Parkinson's disease, multiple sclerosis and psychiatric disorders, he said.
What are the symptoms?
The syndrome includes a spectrum of symptoms and could affect people in different ways, he said.
Muscle rigidity and spasms are the two main defining symptoms of stiff person syndrome, which can be very painful. The spasms can cause people to fall and put them at risk of injury. If the thoracic muscles are affected, people can have difficulty breathing, said Dalakas, noting that spasms can also cause people's voices to tremble.
If the muscle stiffness is severe, "you can become like a statue," he said.
Fear of spasms also causes anxiety and people suffering from the syndrome may be afraid to venture out of their homes.
Although most patients Dalakas sees are mobile, some, especially those who are older, can become physically disabled, he said.
Spasms can be triggered by sudden noises or touch, by phobias or whatever makes the patient uncomfortable, he said.
Is there a cure?
No. But there are treatments that can help alleviate the symptoms.
Medications need to be tailored to each patient, depending on their symptoms, Dalakas said.
Commonly prescribed treatments for stiff person syndrome include diazepam, which can both help relieve muscle spasms and reduce severe anxiety, as well as muscle relaxants and anti-seizure medications like gabapentin.
How is stiff person syndrome diagnosed?
One of the key tests is the presence of antibodies in the blood against an enzyme called glutamic acid decarboxylase (GAD). Specialists may also do a physical examination of the muscles or use electromyography (EMG) to assess muscle and neurological function.
What causes stiff person syndrome?
Like with many autoimmune diseases, the cause is not yet known, Dalakas said.
But there's reason for patients to be hopeful, he said, as the symptoms can often be controlled. The earlier patients are diagnosed and treated, the better their outcomes tend to be.
This report by The Canadian Press was first published December 8, 2022.
This report has been produced with the financial assistance of the Canadian Medical Association. It has no say in editorial choices.
Nicole Ireland, The Canadian Press
