What is stiff-person syndrome? Celine Dion opens up about living with the rare condition in new documentary.

Celine Dion stands at a microphone.
Celine Dion has been speaking up about having stiff-person syndrome, a rare condition that causes her muscles to tense up and spasm. (Kevin Winter/Getty Images for the Recording Academy)

After keeping her diagnosis private for years, Celine Dion is opening up about her experience with stiff-person syndrome in the new documentary, I Am: Celine Dion, which premieres on Prime Video today. Speaking to People ahead of the film's release, the “My Heart Will Go On” singer, 56, revealed that she could barely walk at one point due to the extremely rare condition.

The singer tells People that caring for her three sons following her husband René Angélil’s 2016 death from cancer has motivated her to face her own health challenges. “My kids started to notice. I was like, 'OK, they already lost a parent. I don't want them to be scared,’” she says. “I let them know, 'You lost your dad, [but] Mom has a condition and it's different. I'm not going to die. It's something that I'm going to learn to live with.’"

Here’s what to know about stiff-person syndrome, and how it affects the lives of people like Dion.

Stiff-person syndrome — often called SPS — is a rare autoimmune disorder, meaning that infection-fighting cells in the body mistakenly attack healthy tissues. In the case of SPS, these off-target cells attack the neurological system and deplete its supply of a chemical messenger, called gamma-aminobutyric acid, or GABA, which signals muscles when to relax.

Typically, muscles work in opposing pairs. “When you contract a muscle, the opposite muscle — say, the tricep, when the bicep contracts — relaxes,” says Dr. Marinos Dalakas, a Thomas Jefferson University neurologist who specializes in stiff-person syndrome. “Otherwise, all of us would be stiff.” For people with SPS, that’s exactly what happens, sporadically, causing stiffness in the legs, arms and torso, as well as muscle spasms.

Like many autoimmune diseases, SPS exists on a spectrum and, as a result, symptoms can look quite different in different people, Dr. Scott Newsome, head of the Johns Hopkins Stiff Person Syndrome Center, tells Yahoo Life. The most common form of the disease “typically will present with insidious stiffness in the legs more than the torso,” and some people may have arm stiffness, Newsome says. Symptoms usually appear in middle age, but can strike elderly people and even children.

This stiffness, as well as muscle spasms, can last anywhere from minutes to hours. “Spasms can be prompted by triggers including good or bad stress, hot or cold weather or tactile stimuli,” Newsome adds. Less commonly, someone’s first symptoms might be blurry vision, a wobbly walking gait or a general sense of wobbliness.

As the condition progresses, stiffness may become more widespread and persistent. And stiffness can cause people to become unsteady on their feet, leading not only to falls, but a fear of falling and avoidance of independent activities, experts say. “Anxiety is part of the disease,” says Newsome. “People can have a lot of falls related to balance issues or mobility problems if they have severe spasms. That can lead to people not going outside of their houses.”

No, at least not directly, says Newsome. Many people with SPS eventually may need to use a cane, walker or scooter to get around as their stiffness and spasms progress. But the spasms themselves aren’t fatal. However, falls resulting from stiffness can lead to deadly brain injuries. Some people with SPS also develop swallowing issues that put them at risk for inhaling something that could cause a life-threatening lung infection.

There’s no reason to think the disease itself shortens life expectancy, however, Newsome says that some treatments for stiff-person syndrome could cut life short because they suppress the overactive immune system, which can make someone more vulnerable to infections.

There is no cure for SPS. However, immunotherapy can be used to quiet the overactivity of the immune system. These “are the types of treatments that I feel have the potential greatest impact on preventing progression,” says Newsome. “They don’t reverse time,” he says, and they don’t always work, especially if the disease is diagnosed relatively late. A number of other medications — including anti-seizure drugs, Botox, muscle relaxers like tizanidine and anti-anxiety or sedative medications like Valium — are used to reduce stiffness on a day-to-day basis, according to the Stiff Person Syndrome Research Foundation.

Physical therapy, massage, yoga and therapy or medication to manage anxiety and depression are also important to helping someone with SPS maintain their quality of life, says Newsome. “Using a multi-pronged approach can help patients the most,” he adds.

If you’ve felt stiffness from time to time, it’s very unlikely that you have the disease, Newsome says. Most research suggests that between one and two people out of every million have the condition (though Newsome says recent research suggests it could be considerably higher). Its causes are unknown, as is the reason that it afflicts women more often than men (as is the case with other autoimmune disorders).

Newsome and Dalakas both believe that SPS is at once under- and overdiagnosed. They say it’s often mistaken for another autoimmune neurological disorder, multiple sclerosis, but note that public awareness of SPS is also growing, meaning that more people think they could have it.

Occasional stiffness alone isn’t enough to suggest someone has SPS, but “if there’s a consistency, and you’re noticing worsening of symptoms, you should go and get it looked at,” says Newsome. “That said, most people who have symptoms in common with SPS will not have SPS.”

This article was originally published on June 11, 2024 and has been updated.