Celebrity singer Celine Dion’s announcement in early December 2022 that she has stiff person syndrome – a rare neurological disorder – stunned the world and led to an outpouring of support for the French-Canadian star.
Up until Dion’s reveal, most people had probably never heard of the condition. All over the world, stiff person syndrome it affects only about 1 in a million people, mostly between the ages of 20 and 50, with twice as many women as men having the disorder.
First reported in 1956The classic and most common form of stiff-person syndrome is characterized by painful, fluctuating stiffness, especially in the muscles of the trunk, including the back, abdomen, and upper legs. Patients also experience painful muscle spasms, sometimes triggered by touch or noise.
The onset of the disorder is usually gradual, and those who suffer from it may experience a progressive worsening of symptoms. The experience of living with stiff person syndrome varies from person to person, as it depends on the severity of the symptoms and one’s response to treatment. Ultimately, stiff person syndrome can affect your ability to walk, increasing your risk of falls and the need for assistance with a cane, walker, or wheelchair.
We are specialized neurologists who treat patients with movement and neuroimmunological disorders. Because stiff person syndrome is so rare, patients will typically receive extensive testing from multiple doctors before the condition is diagnosed. In our experience, it’s not uncommon for us to be the third or fourth physician people seek out for an evaluation and diagnosis.
This was originally written by Bhavana Patel, Assistant Professor of Neurology, University of Florida, e Torge Rempe, Assistant Professor of Neurology, University of Florida, and published in The conversation.
Stiff-person syndrome is different from other neurological disorders such as Parkinson’s disease or multiple sclerosis. While people may experience stiffness and cramping in each of these conditions, the underlying cause of the symptoms is different in all three.
Stiff person syndrome is an autoimmune disease – a broad term to describe when the body’s natural defense system mistakenly attacks its own body.
In the late 80s, researchers discovered what are known as “autoantibodies”related to stiff person syndrome. Antibodies are a key part of the body’s defense system to help fight infection or anything that appears to be foreign. So autoantibodies are those that mistakenly target specific receptors, cells or organs in one’s body. But it was the discovery of a key auto-antibody that provided clinicians with important insights into the disease process of stiff-person syndrome and how to manage it with various drugs and immunotherapy.
The human nervous system is composed of various pathways that prevent excessive or insufficient muscle activation. An enzyme called glutamic acid decarboxylase, or GAD, helps convert a neurotransmitter — a chemical that nerve cells use to communicate — called glutamate into gamma-aminobutyric acid, or GABA. This process plays an important role in preventing excessive muscle activity.
Researchers have found that 60% to 80% of people with classic stiff person syndrome have elevated levels of the auto-antibody called anti-GAD. Antibodies against GAD prevent the formation of GABAwhich can then lead to excessive muscle activity such as stiffness.
While anti-GAD appears to be the most common autoantibody in those with classic stiff person syndrome, recent findings have revealed additional antibodies which can also result in the condition.
To date, there is no cure for stiff person syndrome. Current treatments aim to improve stiffness and spasms and modulate the immune system.
Several types of muscle relaxants are used to treat muscle tension and spasms. And some anticonvulsants, used to treat epilepsy, were also shown to reduce muscle spasms.
Doctors can also use treatments that affect the immune system. Evidence is piling up that one treatment, known as intravenous immunoglobulinscan be effective. Immunoglobulins, or antibodies, collected from thousands of healthy donors are administered intravenously at regular intervals to patients with stiff person syndrome to help improve their symptoms.
Alternative treatments for those who do not respond to these approaches may include antibody therapy with the drug rituximab or a procedure called plasmapheresis in which the autoantibodies are filtered out. However, evidence of the effectiveness of these therapies is lacking.
Living with the diagnosis
Doctors like us still have a lot to learn about stiff person syndrome, but increased awareness of this condition can lead to more timely diagnosis and help speed research. And as more people learn about them, they’re more likely to recognize the symptoms and seek treatment sooner.
Patients with milder disease or those who respond well to treatment can continue to function independently while continuing medical therapy. For others, the symptoms may not be fully controlled and could lead to disability.
We recognize that the journey to a diagnosis of Stiff Person Syndrome can be challenging, and receiving the diagnosis can be life changing. But through capable medical teams and other support systems for people diagnosed with stiff person syndrome, researchers like us hope to help patients continue to live life to the fullest.