What Is Multiple Sclerosis?

Multiple sclerosis (MS) is a condition in which the immune system attacks myelin, or the covering wrapped around nerve cells. This disorder ultimately affects the brain and spinal cord, and symptoms come and go in periods of relapse and remission. MS symptoms vary widely, depending on the affected nerves, and include extreme fatigue, numbness, and vision problems.

There are several types of multiple sclerosis, including clinically isolated syndrome (CIS)—which is sometimes known as "singular sclerosis." CIS is one of the first periods of MS symptoms, which lasts at least 24 hours but does not meet the criteria for an official MS diagnosis.

Many other conditions cause similar symptoms as MS. It can take years or even decades for people with MS to receive a diagnosis. Only a healthcare provider can perform tests that confirm the condition.

Types

MS begins with initial symptoms and continues through four phases of the disease. There's also a benign form of MS, which is a steadily mild illness. People have benign MS after having the condition for 15 years without worsening symptoms.

Clinically Isolated Syndrome (CIS)

CIS is one of the first periods of MS symptoms caused by inflammation and demyelination. Demyelination occurs when nerve cells experience damage, which leads to neurological problems. An episode must last at least 24 hours.  

Episodes are either monofocal or multifocal. A singular brain lesion causes one MS symptom in monofocal episodes. Multiple brain lesions cause several MS symptoms in multifocal episodes. CIS does not meet criteria for an MS diagnosis. Your risk of MS increases if an MRI reveals a brain lesion.

Relapsing-Remitting MS (RRMS)

RRMS is the most common type of MS, with about 80% of people with MS experiencing this phase. People with RRMS can have new or increasing MS symptoms, such as:

• Dizziness
• Cognitive deficits
• Muscle weakness
• Numbness
• Tingling
• Trouble controlling bladder
• Trouble walking
• Vision problems (e.g., blurry vision, double vision, or vision loss)

Partial or complete remission may follow an attack. There's no progression of MS during remission. RRMS symptoms may worsen during relapses if untreated.

Primary Progressive MS (PPMS)

PPMS impacts approximately 10% of people with MS and slowly causes worsening neurologic function over time. People with PPMS generally do not experience relapses or remissions, but they may have brief periods of rest. 

A common symptom of PPMS is mobility problems. People may notice increasing stiffness in their legs and have trouble walking.

Secondary Progressive MS (SPMS)

People with PPMS develop symptoms and continue progressing from the beginning without periods of remission. Those with SPMS start with RRMS with periods of remission. The condition eventually starts progressing without further remission.

Multiple Sclerosis Symptoms

MS symptoms result from damaged nerves. These nerves may send mixed signals to different body parts.

Some of the most common symptoms include:

• Balance and coordination issues: Movement problems are a hallmark of MS. People may feel suddenly weak in one limb, or they may find objects slipping quickly out of their hands. You might also be unsteady on your feet and prone to falling if there's damage to the cerebellum. This part of the brain that controls balance.
• Bladder issues: Some people have difficulty emptying their bladder. Others constantly feel like they must go to the bathroom.
• Cognitive difficulties: Memory can be negatively affected if MS causes lesions to accumulate in the brain.
• Constipation: The most common bowel problem related to MS is constipation. The nerves and muscles do not allow your GI system to function correctly.  
• Depression: About 50% of people with MS have depression. Relapses may occur irregularly and cause stress.
• Fatigue: More than 80% of people with MS experience fatigue at one point. Some people experience "MS lassitude," or severe fatigue that occurs daily. Fatigue tends to become worse as the day wears on.
• Muscle weakness: This is most common in the legs, but people with MS may feel it in other body parts. Muscle weakness ranges from a mild feeling of tightness to severe pain. Muscle spasticity can cause a person's body to become distorted and twisted in severe cases. 
• Numbness: This is a lack of sensation in various body parts. Numbness is often one of the first symptoms that people with MS notice and can occur in the face, arms, and legs. You may have trouble walking, holding on to objects, and even chewing as a result.
• Pain: Most people with MS experience pain, which is often the direct result of damaged nerves. You may also feel severe burning sensations in your legs, feet, or hands due to inflammation.
• Sensitivity to certain temperatures: A person with MS may have worsening symptoms and high body temperature on a humid day.
• Tingling: This feels like your arm, fingers, or toes are falling asleep yet never waking up.
• Tremors: Tremors are one of the most common symptoms of MS that impact a person's quality of life.
• Vision problems: These can manifest as double vision, eye pain, blurred vision, or a scotoma (a hole in the vision).
  

Causes

The exact cause of MS remains unknown, but damage to the myelin plays a role. This damage affects the central nervous system and disrupts communication between your cells, brain, and spinal cord. The body's immune system attacks healthy nerve cells, causing inflammation, which results in this damage.

Risk Factors

Some evidence suggests many risk factors that prompt the onset of MS, including:

• Age: MS can strike at any age, but the onset of symptoms is most likely to occur between the ages of 20–40.
• Gender: The disease is much more common in women than in men.
• Genetics: Having a close relative with MS increases your risk. This includes a sibling, parent, or child.
• Low vitamin D: The body produces vitamin D in response to sunlight. People closer to the earth's poles are more likely to experience MS than those closer to the equator.
• Smoking: Smokers and ex-smokers are more likely to get MS than those who have never smoked. The more cigarettes you've had, the greater your risk.
• Viral infections: Some evidence suggests that the Epstein-Barr virus (EBV) is linked to MS, but research is not conclusive. EBV is a member of the herpes family of viruses.
  

Diagnosis

There's no diagnostic test for MS. Symptoms vary widely between people, which makes diagnosis tricky. A healthcare provider may ask you to recount your symptoms and conduct a neurological examination, including:

• An evoked potential test: Looks along the nerve pathways in your central nervous system
• A lumbar puncture (spinal tap): Assesses your cerebrospinal fluid (CSF) for immunological abnormalities
• Magnetic resonance imaging (MRI): Takes detailed pictures of the brain and spinal cord

Treatments for MS

There's no cure for MS, but many treatments may slow its progression. MS treatment typically involves steroids that fight inflammation, such as methylprednisolone, in the acute setting of an MS relapse. A healthcare provider delivers the steroid through a vein in your arm daily for three to five days. You will later take an oral steroid pill and gradually decrease your dose over one to two weeks.

You may take disease-modifying therapies, which prevent relapses during remission periods. A healthcare provider may prescribe other medications that treat specific symptoms.

Other medications include:

• Infusion treatments: Tysabri (natalizumab), Ocrevus (ocrelizumab), Lemtrada (alemtuzumab), Novantrone (mitoxantrone)
• Injectable medications: Beta interferon drugs, Copaxone (glatiramer acetate)
• Oral treatments: Gilenya (fingolimod), (Tecfidera) dimethyl fumarate, (Aubagio) teriflunomide, (Vumerity) diroximel fumarate, (Mayzent) siponimod tablets 
  

Complementary Therapies

Other remedies that help manage MS symptoms include:

• Botox: These injections can alleviate bladder and bowel problems in people with MS.
• Cognitive rehabilitation: Medications don't seem to affect the mental aspect of MS, but rehabilitation methods can help. This may include memory retraining.
• Exercise: Researchers once warned against exercise for people with MS and stated it would worsen fatigue. Others have noted that exercise speeds the progression of MS. Some evidence suggests, in contrast, that exercise is safe. Physical activity can improve strength and mental health. Simply being active while shopping or gardening can be beneficial.
• Speech therapy: Speech pathologists can help with speech difficulties and swallowing. Some people may have long pauses or slurred language. Damage in the areas of the brain that control muscles in the throat may cause swallowing problems, which can potentially lead to choking or aspiration pneumonia. Altering the texture of your food can help.

How To Prevent Flares

There aren't effective ways to prevent MS. Researchers need to know what makes the immune system attack healthy nerve cells, which may help develop preventative therapies.

Identifying environmental factors that trigger MS might prevent the disease. Some risk factors are unmodifiable, like biological sex, genetics, and age. 

Controlling some environmental and lifestyle triggers can help prevent flares. A prominent example is avoiding smoking, as smoking increases your risk of MS and its severity and speeds the progression of the disease.

You can also increase your vitamin D intake. Research has found a link between location and MS: Rates are highest in North America, Southern Australia, and Northern Europe. The farther you live from the equator, the greater your risk. This link may be sun exposure or vitamin D levels in the body. The human body generates vitamin D in response to sunlight.

Related Conditions

Research has found that MS often occurs with several other health conditions. People with MS are more likely to develop the following:

• Anxiety and depression: It's not uncommon for people with MS to have feelings of stress and helplessness due to the unpredictability of flares. These feelings cause an increased risk of anxiety and depression, which can affect the severity of symptoms. Counseling and building support systems can help prevent adverse mental health effects.
• Autoimmune disorders: MS shares risk factors with many other autoimmune disorders, such as thyroid disease, rheumatoid arthritis, and inflammatory bowel disease (IBD).
• Chronic lung disease: Nearly 10% of people with MS also have chronic lung disease. Research has shown that chronic lung disease is most common in people 45 and younger.
• Gastrointestinal (GI) disease: IBD is more commonly reported among people with MS than others. Similar immune responses to the conditions may explain this link.
• Vascular and cerebrovascular diseases: Vascular diseases include high blood pressure and cholesterol. Cerebrovascular diseases include cognitive dysfunction. The risk of these conditions increases with age.
  

Living With MS

MS is typically not a fatal condition. Research has found that people with MS had a seven-year shorter lifespan than the general population. Effective therapies and treatments allow people with MS to manage their symptoms and mitigate flares. These flares can be random, making daily activities stressful.

Some methods to help cope while treating MS include:

• Build a support system: Family and friends may help your condition feel less stressful. A support group of others dealing with MS may also be helpful.
• Eat a balanced diet: No special diet prevents MS or cures its symptoms, but diet can affect specific symptoms. Low-fat, high-fiber foods that give you energy can help you avoid fatigue.
• Exercise: Exercising helps improve your health. Try strength exercises, yoga, or Tai Chi.
• Prioritize sleep: Some people with MS have sleep issues. Insomnia, frequent nighttime urination, narcolepsy, and leg spasms are common. A good night's sleep helps prevent fatigue, so it's essential to prioritize it.