In an emotional, five-minute Instagram video posted Thursday, 54-year-old Dion told fans: “I have been dealing with issues with my health for a long time and it was very difficult for me to face these challenges. and talk about everything I’ve been through.”
What is Stiff Person Syndrome? We spoke with neurologists and a pain specialist to answer common questions about the unusual condition, including how it’s diagnosed and whether it affects longevity.
Andrew McKeon, a professor of neurology at the Mayo Clinic, said SPS affects nerves in the spinal cord and neurons in the brain that regulate movement. In other words, when the nervous system becomes overly excited, it can send too many signals to the muscles, causing them to stiffen or spasm.
A person’s “entire body can get stuck when startled or in other situations,” putting them at risk for falls and injuries, he said.
The syndrome affects women twice as fast as men, experts say, and while it can affect a person at any age, it’s most commonly diagnosed in middle-aged people.
What are the symptoms? Is it painful?
SPS causes muscle stiffness, muscle pain and spasms, often in the lower back and legs, making it difficult for some patients to walk. Those with symptoms that are not well controlled may need to use a walker or wheelchair to avoid falling or injuring themselves.
The muscle spasms are what neurologists call “stimulus sensitive” and can be triggered by a sudden noise, light touch, or even emotional stress. One form of the condition can affect muscles that control eyes, speech or singing or swallowing.
“Imagine having the worst Charley horse you can have, but it affects a lot of muscles in your lower back and legs – and that’s constant. It’s very painful,” says Kunal Desai, an assistant professor of neurology at Yale University.
Chi-Ying “Roy” Lin, a neurology professor specializing in movement disorders at Baylor College of Medicine, said that in the cases he’s seen, patients were “very, extremely uncomfortable and usually very painful.”
And when the pain comes on, it’s very debilitating no matter the position, he added. “There’s really no comfortable position for them to stay in, sitting or lying down.”
The condition usually only affects skeletal muscles that we can voluntarily control. It does not appear to affect cognition, but may be associated with anxiety.
In her statement, Dion said the spasms have made her life difficult.
“Unfortunately, these spasms affect every aspect of my daily life, sometimes causing difficulty walking and preventing me from using my vocal cords to sing like I used to,” she said.
Due to her diagnosis, the singer said she “will not be ready to restart my tour in Europe in February”.
What is the life expectancy for someone with stiff person syndrome?
While SPS is rare and not fully understood, experts say the syndrome typically has no effect on longevity, except in very rare circumstances where the muscles used for breathing or swallowing are affected.
When symptoms are well controlled, patients can lead relatively normal lives. However, when symptoms can’t be controlled, they can become significantly impaired, experts say.
Lin said the main effect is quality of life. “I don’t think for the cases I’ve seen, their quality of life ever returns to normal baseline,” Lin said.
What causes it? What are the risk factors?
SPS is thought to be an autoimmune disease in which the immune system is overstimulated and generates antibodies that target neurons that inhibit activity in the brain. There’s no clear mechanism as to why these antibodies are generated, Lin said.
Most SPS patients have antibodies against glutamic acid decarboxylase, or GAD65, an enzyme that produces the important inhibitory brain chemical GABA. The immune response against GAD65 can reduce the amount of GABA that normally inhibits neuronal activity, amplifying the neuronal signals sent to the muscles, which can cause spasms.
Although it was originally called stiff man syndrome when it was first described in 1956, most of the patients diagnosed are mostly middle-aged white women, although it can occur in patients of different ages and backgrounds.
Although a rare disease, when diagnosed it is common to see it alongside other conditions, including diabetes, thyroid disease, and pernicious anemia.
“The world will benefit from more understanding about this disease because it is so rare,” Lin said.
How Is Stiff Person Syndrome Diagnosed?
SPS is diagnosed based on symptoms, through neurologic and neuromuscular exams, including the use of electromyography or EMG to test muscle and nerve function. Diagnosis also often depends on a blood test that measures the GAD antibody.
Because the symptoms can share similarities with multiple sclerosis and various muscular dystrophies, it “can be a challenging diagnosis to make, and it requires some expertise,” McKeon said.
Lin notes that it’s very common to have some muscle spasms in normal, day-to-day life and that very low levels of antibodies against GAD65 are not abnormal. For the diagnosis of stiff person syndrome, the amount of antibodies against GAD65 must be very high.
How is it treated?
There’s no cure for SPS, but it can be managed, experts say.
Treatment focuses on directly targeting the nervous system to restore balance, as well as targeting the immune system to prevent it from attacking the nervous system, McKeon said.
For patients with an autoimmune cause, treatment may include intravenous immunoglobulin (IVIG), a treatment that uses antibodies to suppress the immune response. Other treatments include the use of muscle relaxants, anticonvulsants, and pain relievers for those experiencing pain.
In addition, Pavan Tankha, medical director of Comprehensive Pain Recovery at the Cleveland Clinic, said he refers patients to pain psychologists, physical therapists and other health professionals “to try to improve their overall quality of life and reduce the suffering associated with pain.”
“Pain is just not what you feel; it’s also what it does to you,’ he said.