Millions of people live with multiple sclerosis - So why don't we have a cure?

Multiple sclerosis (also known as MS), the neurological and autoimmune disease that impacts millions of people around the world, is on the rise. As the number of diagnosed cases continues to climb, many people are surprised to learn that we have not been able to identify a cure — or even a specific cause — for the disease.

As little as twenty years ago, there were next to no available treatment options for anyone diagnosed with multiple sclerosis. Thankfully, due to increased pressure from the general public and global health organizations, increased funding to MS research has resulted in the creation of treatment options that now are helping millions of people live longer and happier lives once diagnosed with the disease.

While cases of multiple sclerosis have been documented and observed as early as 1300, the disease wasn’t properly identified or named until 1868 by neurologist Jean-Martin Charcot¹. Since then, the number of people living with the disease has exploded, with over 2.3 million people living with MS around the world today². As a degenerative disease, multiple sclerosis patients experience worsening symptoms over time, requiring more care and more comprehensive treatment as the disease progresses.

Because MS targets and impairs the function of the nervous system, symptoms of the disease often become widespread around the body as more neurons are damaged. Causing widespread and diverse symptoms that can impact a person’s senses, muscular function, vision, digestive system, urinary function, and cognitive capabilities, patients diagnosed with MS often experience profound changes to their day-to-day lives the longer they are living with the disease³.

So, the question still stands — with the rising number of cases, improved modern research techniques, and increased awareness of the disease, why have we not been able to find a cure?

What is multiple sclerosis?

To better understand multiple sclerosis, we must first explore the pathology of the disease. The immune system, which is our body’s naturally occurring defensive system against foreign pathogens in our environment, can at times become overactive. When this occurs, immune cells can attack and destroy healthy body tissue, resulting in the formation of an autoimmune disorder. In the case of multiple sclerosis, the body’s neurological system is the victim of immune system attacks.

Healthy neurons in the brain and spinal cord are surrounded by an insulating layer of fatty substances and proteins called the myelin sheath⁴. Protecting the delicate nerve cells, the myelin sheath also helps to increase the speed of electrical impulses that pass from the central nervous system out to the peripheral nervous system⁴. Damage to the myelin sheath (caused by the immune system) results in the development of multiple sclerosis, resulting in slowed nerve impulse transmission and the emergence of motor and sensory deficits⁴. Currently, we do not have any way to reverse damage to the nervous system caused by MS.

Motor symptoms are just the tip of the iceberg

When most people think about MS, they commonly think about the motor symptoms that become more apparent as the disease progresses. And while changes in a person’s motor function definitely have a major impact on their day-to-day routines, there are a variety of other symptoms that also have a profound impact on their quality of life.

Because multiple sclerosis attacks the nervous system, every single body system will eventually become impacted and impaired. Commonly referred to as a metaphorical iceberg, the extent of MS symptoms is much, much deeper than many people can even imagine.

The types and timeline of multiple sclerosis

As a progressive disease, multiple sclerosis patients typically experience worsening and more severe symptoms over time. Monitored using a multiple sclerosis progression chart, a person’s symptoms can be charted and observed to better understand the speed at which their symptoms are emerging and worsening. The MS progression chart is divided into ten distinct levels⁵:

1. Minimal symptoms impacted one area of the body, but no identified disability.

2. Minimal disability impacted one area of the body. A person may require minor assistance to correct this change and may have to make minor changes to their day-to-day lifestyle.

3. Moderate disability in one area of the body, or mild disability in three to four body systems. No current walking impairment.

4. Significant disability in multiple body systems, but still able to perform self-care activities. At this stage, the person is still able to walk unassisted for at least 500 meters.

5. Disability is now significant enough to impact a person’s ability to participate in activities of self-care. They also require assistance or a walking aid to walk up to 200 meters.

6. Disability worsens, and the person can now only walk up to 100 meters with assistance or walking aid.

7. Must use a wheelchair for all transportation, but can move themselves in and out of the chair and can use the wheelchair independently.

8. The person needs assistance to use the wheelchair. They are still able to use their arms and hands for some basic self-care tasks.

9. Unable to leave the bed without a lift or extensive assistance. They are able to communicate and eat.

10. Unable to eat, communicate, or move as a result of severe loss of neurological function. At this stage, a person will pass away as a result of their multiple sclerosis symptoms.

It is important to note that not all patients with MS progress through this chart in a linear way, or even at all. Like many other autoimmune diseases, every patient experiences the disease differently. With the many differences in presentation, researchers have been able to identify three main categories of multiple sclerosis⁶:

Relapsing-Remitting MS (RRMS)

The most common type of MS worldwide, people with RRMS experience recurrent random episodes of disease relapses and remissions. During relapses, a person can experience a profound onset of disease symptoms. During periods of remission, a person can either return completely or partially to their baseline over time.

Secondary-Progressive MS (SPMS)

Patients with secondary-progressive MS are often first diagnosed with RRMS. Starting with a few cycles of relapse and remission, SPMS patients often experience significant disease progression and worsening over time. While they may still have occasional remissions, once a patient is diagnosed with SPMS, it is very common for their disease to progress at a rapid rate.

Primary-Progressive MS (PPMS)

The most common characteristic of PPMS is steady disease progression without few to no episodes of remission. Roughly 12% of patients with MS are diagnosed with this type of disease, which is known to be the most severe and difficult to manage form.

We don’t know much about what causes multiple sclerosis

Despite its growing prevalence, one of the many mysteries surrounding multiple sclerosis is what causes the disease to occur in the first place. With a multitude of possible causes being researched, some of the most commonly accepted and supported theories include:

It could be in our genes

While multiple sclerosis is not considered to be an inherited disease, it has been proven that some individuals can be predisposed to developing the disease based on their genetics. On average, 15% of people diagnosed with MS have one or more blood relatives who also have the disease⁷.

Additionally, women appear to be at a higher risk of developing MS, outnumbering men diagnosed with the disease almost 4:1⁷.

Like many other diseases, research has found a link between our genetics and the risk of developing multiple sclerosis. The HLA-DRB1 gene (which is associated with helping the immune system identify the difference between pathogens and healthy body cells) is believed to be involved in the development of multiple scerlosis⁸. Variations and mutations in this gene can be passed down from family members, which explains why individuals born to people with MS are at an elevated risk of developing the disease themselves.

New research shows MS could be linked to infections in childhood

Another possible cause for the development of multiple sclerosis is believed to involve a common infection that impacts millions of people around the world. The Epstein-Barr virus (also known as human herpesvirus 4), is found around the world in high volumes. Contracting Epstein-Barr virus can result in the development of infectious mononucleosis, which is commonly known as a mono infection⁹. With the majority of people living today being exposed to or infected by this virus during their lifetime, it is suspected that those who have experienced infectious mononucleosis are at an elevated risk of developing MS¹⁰.

Our environment plays a role

Where we live plays a huge impact on our lifestyle and overall health — and as it turns out, it may also play a role in the risk of developing multiple sclerosis.

Our geographical location has an impact on the amount and quality of exposure to sunlight that a person gets every day. Important for the development of vitamin D in the human body, getting adequate amounts of exposure to sunlight is essential for overall health. Modern research has shown that people with vitamin D deficiencies (commonly due to living in a colder and darker climate) are associated with an elevated risk of developing multiple sclerosis¹¹. This concept is supported when looking at the countries with the highest diagnosis rate of MS, which include northern and colder climate countries such as Canada, Denmark, Sweden, Hungary, and The United Kingdom⁷.

How is multiple sclerosis currently being treated?

Currently, our best line of action against multiple sclerosis is to slow the progression of the disease. Disease-modifying therapies (DMTs) are a category of drugs that are designed to augment specific cells in the immune system. Now considered to be the gold standard treatment for those with RRMS, drugs like Ocrelizumab that target specific immune cells that are associated with autoimmune disorders have become quite successful at slowing down the development of MS symptoms and loss of brain volume mass caused by the immune system¹².

The majority of DMTs approved by the Food and Drug Administration (FDA) since the 1990s have been proven to have long term benefits and success rates for those living with MS. Relapsing-remitting MS, which is the most common form of the disease affecting 85-90% of people with MS, responds the best to DMT treatment¹³. More research is needed to be done to identify more successful treatment options for those living with other forms of the disease, as well as hopefully finding a cure for MS once and for all.

Why don’t we have a cure? What is next for MS research?

As modern research continues to search for a cure for multiple sclerosis, it can be hard not to wonder how we haven’t already arrived at a solution. With increased awareness and funding for this disease, many people are hopeful that a cure for the disease is just around the corner — despite any significant evidence that this is the case.

A large hurdle for the development of any disease cure is the development of pharmaceutical treatment options. With the average drug trial period taking anywhere between 10-15 years to complete, there is no way to quickly mass-produce a safe medication. Extensive safety, quality, and efficacy testing need to be conducted before medication can even enter into clinical trialing — the phase of the FDA’s approval process that results in the rejection of countless medications due to lack of clinical results or the development of adverse side effects. Additionally, of the small number of drugs that make it through clinical trials, an estimated 25-30% of drugs make it to the next stage of the process after FDA approval¹³. So, while new research and treatment plans are being worked on, it appears that we are at a bit of a standstill when it comes to developing effective treatment options for MS.

With this in mind, many non-profit medical societies and neurology researchers are using their funding to explore a wide variety of different potential treatments for MS, including¹⁴:

• Exploring the role of the gut biome and diet in relation to MS

• Learning more about the process of myelination, with the hope of learning how to restore myelin lost to multiple sclerosis

• Identifying biomarkers that indicate the progression of the disease for earlier and more accurate detection

• Better treatment options for those with secondary or primary progressive disease

• Increased genetic research to identify why individuals are more susceptible to developing the disease

• The development of neuroimaging tools, which would be used to better diagnose and pinpoint disease progression

With these topics and many more being explored by researchers around the world, the multiple sclerosis community is hopeful that a cure for the disease may be closer than we think. With increased awareness of the disease and support for future research, many are hopeful for the day that MS is no longer a life-long diagnosis.

Sources:

1. History of Multiple Sclerosis | Multiple Sclerosis Association of America

2. Multiple Sclerosis: Progress, but No Cure (2015)

3. Symptoms of multiple sclerosis | National Health Service

4. Myelin | MedlinePlus

5. What to Know About Multiple Sclerosis Progression in Chart Form | Healthline

6. Types of MS | MS Society of Canada

7. Multiple Sclerosis: Facts, Statistics, and You | Healthline

8. Multiple sclerosis | MedlinePlus

9. About Epstein-Barr Virus (EBV) | Centers for Disease Control and Prevention

10. The role of Epstein-Barr virus in multiple sclerosis: from molecular pathophysiology to in vivo imaging (2019)

11. Vitamin D | MS Society of Canada

12. OCREVUS® (OCRELIZUMAB) | Genentech

13. Multiple sclerosis: Are we close to a cure? | Medical News Today

14. Multiple Sclerosis: Hope Through Research | NIH: National Institute of Neurological Disorders and Stroke

The author, Claire Bonneau, is a medical writer and certified trauma operating room nurse.