What IS the mysterious illness afflicting Celine Dion as the singer bravely releases a film of a painful attack… and who is at risk?

Canadian singer Céline Dion is being praised for courageously sharing harrowing images of what it’s like to live with Stiff Person Syndrome (SPS).

In the terrifying clip, Dion, 56, is seen gasping for air and whimpering in pain, unable to control her own body.

Doctors desperately try to relieve her painful spasms, while a film crew silently records the incident.

Dion was convinced the entire scene would be included in her new documentary I Am: Céline Dion on Amazon Prime, which takes a heartbreaking look at how the star lives with SPS.

In the aftermath, she immediately added, “Every time something like this happens, I feel so ashamed.

“I don’t know how to express it, you know, that you have no control over yourself.”

Dion revealed her diagnosis with SPS in 2022, but had been secretly living with the condition for 17 years.

SPS is an autoimmune disease, meaning its symptoms are caused by the immune system, which normally protects the body by attacking pathogens, accidentally damaging healthy tissue.

For SPS patients, this takes the form of blocking an enzyme that regulates the body’s nervous system, which controls our ability to control our movements and respond to stimuli, so it doesn’t work properly.

This can result in extreme muscle stiffness that seriously affects mobility and can turn patients into ‘human statues’, causing them to have difficulty walking or talking.

As Dion showed in her documentary, this can also lead to spasms, because the nerve cells do not work properly and they have enough force to potentially break bone.

Other signs of the condition include increased sensitivity to noise, sudden movements and emotional distress – as natural responses fail.

This could mean that something as simple as a knock on the door can trap a patient in their own body.

Here, MailOnline explains everything we know about the extremely rare condition:

What is stiff person syndrome?

Stiff Person Syndrome (SPS) is an extremely rare condition in which the muscles in the trunk and limbs are alternately cramped and stiff.

It is also called the ‘human statue disease’. The spasms it causes can be so severe that they dislocate joints and break bones.

Estimates suggest it affects around 70 people in Britain, and just 330 in the US. About twice as many women as men are affected.

It was thought to be so rare that it affects only one or two people in a million.

SPS usually occurs in people between the ages of 40 and 50, but rarely affects younger or older people.

Women are also generally more likely to develop SPS.

The disease becomes more severe over time and can paralyze patients, requiring them to use a walker or wheelchair.

There are three main types of the syndrome:

• Classic stiff person syndrome: When there is stiffness and spasms around the back and abdomen, and sometimes also around the thighs and neck. It can cause back curvature over time.
• Stiff Limb Syndrome: Spasms mainly affect the legs and feet, causing them to occasionally lock in place. Hands can also be affected.
• Jerking stiff person syndrome: The rarest, most aggressive form, which includes symptoms of both others, and also affects the head and eyes.

What causes it?

Experts do not yet know what causes the disease.

But they believe it may be caused by an autoimmune response in which the body attacks its own nerve cells that control muscle movement.

About 40 percent of patients also have type 1 diabetes, another autoimmune disease. Type 1 diabetes is mainly associated with the classic person syndrome.

Other autoimmune diseases such as vitiligo, which causes white patches on the skin, and pernicious anemia, a lack of red blood cells, are also associated.

The condition is also more common in people with breast, lung, kidney, thyroid or colon cancer, and in lymphomas. Researchers do not yet know why.

In ‘stiff person syndrome’, the immune system attacks a protein that helps produce gamma-aminobutyric acid (GABA), which regulates motor neurons – the nerves that control movement.

Low GABA levels cause the neurons to continuously release unwanted signals, resulting in spasms and stiffness.

What are the symptoms?

The main symptoms of ‘stiff person syndrome’ are spasms and stiffness of the trunk and limbs.

Spasms can be caused by loud noises, with the condition also causing increased sensitivity to sound.

Touch and emotional stress can also be experienced more intensely as a result of the condition.

The spasms can be so severe that people may fall or have difficulty walking or other disabilities.

Stress and anxiety also tend to be higher in people with the condition, mainly due to the unpredictability of spasms.

The lack of GABA – which regulates anxiety – in their system also impacts mental health.

How is the diagnosis made?

Due to its rarity and baffling symptoms, which are often mistaken for Parkinson’s disease or multiple sclerosis (MS), diagnosing the syndrome can take a long time.

But if doctors suspect stiff person syndrome, they can confirm it with two tests.

The first looks for antibodies against the aforementioned protein, called glutamic acid decarboxylase (GAD), in the blood.

High levels of GAD antibodies may indicate Stiff Person Syndrome, although levels are also elevated in people with type 1 diabetes.

The second test is an electromyogram (EMG), which assesses the health of the muscles and motor neurons.

Doctors insert a needle directly into the affected muscles and record the electrical activity there.

Is there a cure?

No. However, treatments can be given to control symptoms.

Medicines such as diazepam and baclofen – both of which control spasms – can help regulate episodes and reduce stiffness.

Some patients with more severe symptoms also receive therapies to manipulate their immune system to increase GABA levels.

In some cases, immunoglobulin transfusions may be given to influence antibody levels in the blood.

Medications such as tranquilizers and steroids may also be prescribed, again to relieve symptoms.

At the same time, patients are often prescribed physiotherapy and aqua therapy to improve their muscle function.

Can it be fatal?

Yes, but this is usually not directly caused by the condition itself.

Instead, fatalities from SPS usually occur as a result of injuries or subsequent infections due to the spasms.

Blood clots in people rendered immobile by the condition have also been reported.

In extreme cases, SPS spasms in the chest muscles can also be dangerous and hinder a person’s ability to breathe.