Multiple Sclerosis (MS) is a progressive and chronic autoimmune disease that develops because the immune system mistakes healthy cells for unhealthy ones and attacks them. MS affects the central nervous system (CNS). The CNS is made up of the brain and spinal cord and acts as a communication pathway between the brain and the rest of the body.
What Is Having MS Like?
When MS develops, the immune system attacks the protective coating (myelin sheath) on the nerves in the brain and spinal cord. The attacks damage the nerves and cause symptoms such as fatigue, difficulties with walking, weakness, muscle stiffness, and vision problems. MS can be disabling as the disease progresses and its symptoms worsen.
The number of people living with MS grows each year, but the total number of cases is only an estimate because there is no registry available to track new cases. Read on to learn more about MS prevalence worldwide and the current state of MS research.
Group of young adults, photographed from above, on various painted tarmac surface, at sunrise.
What Causes MS?
Prevalence
The prevalence of a disease like MS is a measure of how many people in the general population have it. Prevalence can be expressed in a percentage or number. While prevalence statistics are only estimates and based on available data, they can paint a picture of how many people are affected by a disease at any given time.
Prevalence numbers can provide medical professionals with insight into the needs of people with MS, as well as the economic burden of the disease.
The numbers range significantly by region, but the total number of adults with MS in the United States is estimated to be roughly 1 million.1
An estimated 2.8 million around the world have MS—and that number grew from 2.3 million in 2013. The majority of the 2.8 million people that are diagnosed with MS are adults, however, roughly 30,000 people living with MS are under the age of 18.2
Can Kids Have MS?
Diagnosis Rates
Worldwide data suggest that every region in the world has seen an increase in people being diagnosed with MS since 2013. However, there are still gaps in former estimates about how many people have the disease.3
For example, certain methods are used to come up with an estimated number of cases. A 2020 report found that when using the typical method from 2013 to estimate the numbers today, the estimates were off by roughly 30%. When looking at the rates of diagnosis per year, that same report saw that roughly 2.1 people out of every 100,000 people are diagnosed with MS each year.3
According to a comprehensive study of worldwide cases of MS, the Atlas of MS, someone in the world is diagnosed with MS every five minutes.2
Diagnosis rates vary based on region, sex, age, and ethnicity. Women make up the majority of MS cases in the world and are twice as likely to have MS as men. In some areas of the world, there are four cases of MS in women to every one case in men.
The onset of MS typically occurs between the ages of 20 and 50, and the average age at which someone is diagnosed is 32.3
Does MS Affect Life Expectancy?
Multiple Sclerosis Statistics
Global MS prevalence statistics that include ethnicity and region can show where MS is most documented, as well as who is the most affected by the disease.
By Region
Although MS has increased in every region of the world, some areas are more affected by the disease than others. Research has shown that people who live farther from the equator are more likely to be diagnosed MS than people who live closer to it. This factor may also play a role in why certain ethnic groups are more affected by MS than others.
North America is home to the most people with MS, followed by Europe. The regions of the world that are least affected by the disease are Australasia (Australia, New Zealand, and neighboring islands), Africa, and Oceania (areas of the central Pacific Ocean, such as Micronesia and Polynesia).4
By Ethnicity
A person of any ethnicity can develop MS, but some groups are more likely to be diagnosed with it than others. According to the National Multiple Sclerosis Society, white people of European descent are the most likely to be diagnosed with MS. However, more recent data has shown that Black women have a higher risk of developing MS than researchers originally thought.5
The Multiple Sclerosis Association of America looked at data to determine which ethnic groups are most or least affected by MS. People of northern European, including those of Scandinavian descent, are the most likely to develop MS.6
Caucasians are more likely to develop MS than people of other races/ethnicities.
In the United States, white Americans are affected by MS more often than people of other racial/ethnic groups. However, MS also occurs in Black, Hispanic, and Asian Americans.7
In fact, the numbers of Black and Hispanic Americans being diagnosed with MS are increasing in the United States, which shows that the long-held notion that Black Americans are a low-risk population for MS is not necessarily true.7
What Is Late-Onset MS?
Other Facts About MS
When looking at the worldwide prevalence of MS, income appears to be another contributing factor. According to the Atlas of MS, people with higher incomes are more likely to be diagnosed with MS than people with lower incomes.2
A person’s socioeconomic status has also been linked to MS disease progression. One study found that people with MS who live in neighborhoods of lower income levels are more likely to reach disability than people living in higher-income areas.
Although the study did not look at why having a lower income may increase the chances of disability for people with MS, the authors suggested that diet and exercise, among other lifestyle factors, may contribute.8
Research findings on socioeconomic status and disease progression in people with MS have led to the assumption that people who have the means to participate in activities or access treatments that improve MS symptoms are less likely to become disabled by the disease.8
Economic Burden of MS
Rates of MS continuing to climb, and people with the disease are forced to utilize health care more often than people who do not have a chronic health condition. As the disease progresses, so does a person's need for health care.
Research has found that although people with MS use more healthcare resources than people who do not have MS, many of them have insurance. Roughly 53.9% of people with MS have private health insurance, 39% have federally funded health care such as Medicare or Medicaid. That leaves 7.7% of people with the disease being uninsured.9
However, the costs associated with MS treatment can be high even with insurance, as some specialty drugs can cost more than $600 per month. Annually, the out-of-pocket costs for people with MS can range from $5,900 to $6,400 a year.
With all the variables that go into insurance plans—such as what is covered and the amount of coverage available—the proper treatment and management of symptoms and disease progression in people with MS might be out of reach for many people with the condition.
According to meta-analyses on the overall economic burden of MS, regardless of insurance coverage or income, it costs roughly $4.1 million dollars to treat one MS patient for their entire life.9
Ongoing Research
The main goal of studying MS is to figure out what causes it and find new and better ways to treat it. Ongoing research will help more people access treatment that could reduce their symptoms and help prevent disability.
Specific areas of ongoing MS research include the following:10
Biomarkers to help diagnose MS and monitor disease progression
Genetic and environmental risk factors that contribute to the development of the disease
How diet and the collection of bacteria in the gut (microbiome) affect MS
The mechanisms that cause sex-linked disparities in MS onset and progression
How the immune system contributes to MS and its symptoms in relation to the central nervous system
The risk factors and progression of the disease in ethnic populations that were formerly considered low risk
The basic function of myelin in the body and ways to overcome the loss of myelin that occurs in MS
6 Foundations Looking for a Cure for MS
Summary
MS is considered the most widespread disabling disease in young adults and its prevalence is rising around the world. In fact, some populations that were previously considered to be at low risk for developing MS have also seen rising case numbers in recent decades.