What Happens if Multiple Sclerosis Goes Untreated?

Multiple sclerosis drugs have been proved to reduce relapses. But some with MS still say no to treatment.

Medically Reviewed
doctor and patient looking at brain scan
In active MS, lesions form in the brain and sometimes the spinal cord.Getty Images

In many chronic conditions, the way the disease will progress over months or years is relatively predictable. That’s not the case with multiple sclerosis (MS); while some people with the disease may be only mildly impacted over years or even decades, others may lose their ability to walk, speak, or swallow over time. And many are affected cognitively, meaning their ability to think, focus, and remember may be impaired, making it difficult to hold down a job.

Because the course of MS can vary dramatically from person to person, it’s hard to know with absolute certainty what the prognosis will be for an individual who doesn’t get treatment. But that lack of predictability doesn’t mean a “wait and see” approach is a good idea, says Justin Abbatemarco, MD, a neurologist at the Cleveland Clinic who specializes in treating multiple sclerosis.

“After an MS diagnosis is confirmed, we usually would initiate or recommend some form of treatment, just because we know the outcome for most patients who remain untreated,” says Dr. Abbatemarco.

“There is evidence that patients [with relapsing-remitting MS (RRMS)] who remain off MS disease-modifying therapies will have more frequent relapses and more frequent disability accrual, and they’ll have a higher chance for developing secondary-progressive multiple sclerosis (SPMS),” Abbatemarco says.

SPMS is generally regarded as a stage of MS that follows RRMS, during which there is a steady progression of symptoms and disability, without noticeable periods of remission.

On the other hand, a study published in January 2019 in the Journal of the American Medical Association provides some evidence that treatment with more highly effective MS therapies soon after diagnosis is associated with a lower risk of transitioning to SPMS.

Disease Course of MS Is Unpredictable

About 5 to 10 percent of people diagnosed with MS have what’s known as benign multiple sclerosis, according to John Hopkins Medicine. A person with benign MS will have few symptoms or loss of ability after having MS for about 15 years, while most people with MS would be expected to have some degree of disability after that amount of time, particularly if their MS went untreated.

“The problem is, we have no way of identifying these people,” says Barbara Giesser, MD, a neurologist and MS specialist at the Pacific Neuroscience Institute in Santa Monica, California. “We can’t tell at the outset if someone is going to have a very benign course or if their relapsing-remitting MS will move on to progressive MS.”

While “ultimately, it’s up to the patient what they want to do,” Dr. Giesser says, “most MS-ologists and neurologists would recommend starting treatment once you have a diagnosis.”

What Causes Disability Progression in MS?

There are two main components that cause disability progression in MS, says Abbatemarco. “One is inflammatory activity in the central nervous system, and the other is neurodegeneration within the brain and spinal cord,” he says.

Neurodegeneration is the loss of structure and function of the nervous system, particularly the neurons, or nerve cells, of the brain.

The origin and development of the neurodegenerative aspect of MS is less understood, Abbatemarco adds.

In relapsing-remitting MS, inflammation appears to be the main driver of damage to nerve cells — and therefore symptoms — with less neurodegeneration occurring early in the disease process, according to the Multiple Sclerosis Association of America. In the progressive forms of MS, the opposite is thought to be true: There is predominately neurodegeneration and less inflammation.

“Right now, the MS medications address the inflammatory component of the disease,” says Abbatemarco. They can help prevent acute MS attacks, or relapses, which in turn prevents the residual symptoms and disability that can linger after a relapse.

Unfortunately, we don’t have medications that are as good at treating the neurodegeneration part of MS, though there are a lot of active clinical trials trying to answer that question, says Abbatemarco.

That means there are few treatment options for people with primary-progressive MS (PPMS), although the drug Ocrevus (ocrelizumab) has been shown to slow disability progression in some people with PPMS.

Treatment Is Recommended for People With Active MS

Because it’s impossible to know what the course of anyone’s MS will look like, “It’s almost universal that we recommend treatment for patients with active multiple sclerosis,” meaning they experience relapses and their MRI scans show new lesions, or areas of damage, over time, says Abbatemarco.

One reason why it's important to prevent MS relapses through the use of disease-modifying drugs is that there aren’t medications available to help with regaining any function that’s been affected by a relapse, says Abbatemarco.

Abbatemarco’s recommendations align with the 2018 updated guidelines for treating MS from the American Academy of Neurology, which were reviewed and confirmed in 2021. The new guidelines state that in most cases, it’s better to take medications for MS early rather than let the disease run its course.

While MS treatment isn’t deferred if the MS diagnosis is secure, it might be postponed during the diagnosis “odyssey,” says Abbatemarco. “In a patient where MS is suspected but not confirmed, we would be watching closely and having regular MRI monitoring if treatment hasn’t yet been started,” he says.

Medication Is ‘One Piece of the Puzzle’ in MS Treatment

“When patients come to see us in clinic, we spend a lot of time talking about disease-modifying therapies for MS, but that’s just one piece of the puzzle,” Abbatemarco says.

Rehabilitation, with the goal of improving and maintaining function, is also an important part of the treatment plan, he says. “We enlist the help of physical therapists, occupational therapists, neuropsychologists, and other members of the rehabilitation team to take a more holistic approach to treating MS and keep the patients well,” he says.

A healthy diet and regular exercise are also part of the treatment plan, he says.

“We work to manage vascular risk factors such as hypertension, diabetes, and smoking. We know that all those other pieces can also worsen MS, so keeping focused on wellness is truly important. I always emphasize the importance of a healthy lifestyle; it can be empowering for people to realize they have some control over their disease,” says Abbatemarco.

Work With Your Doctor to Find an MS Treatment Plan That Fits You and Your Lifestyle

“When discussing therapy options with patients, I always talk about the data: Overall, they will do better on disease-modifying therapies in the long term,” Abbatemarco says.

He points to the advancements that have been made in MS treatment over the last few decades. “The first therapy came out in 1993, and really through the 1990s and early 2000s, we only had a few choices for patients to select from. Most of those were injectable therapies, which came with some significant side effects,” he says.

Today, there are more than 20 disease-modifying therapy options for people with MS, says Abbatemarco. “There is a wealth of options, and we’re almost always able to find a medication that works with a patient’s lifestyle and with a side effect profile that’s manageable,” he says.

“People who are hesitant to start MS therapy or have concerns about their current treatment should have an open conversation with their providers so they can find a drug that works for them,” says Abbatemarco.

If you’re unsure about your doctor's recommendation, you can always seek a second opinion, he says. “It can be helpful to get another perspective about the available treatment options out there. We absolutely know that good adherence to long-term disease-modifying therapy will lead to the best outcomes available.”