Multiple sclerosis is a progressive disease of the central nervous system. It occurs when the body's immune system mistakenly attacks the healthy nerves of the brain and spinal cord.
According to the National Multiple Sclerosis Society, the disease affects nearly 1 million people in the U.S.
The National Institutes of Neurological Diseases and Stroke put the figure at 250,000-350,000, but they add that it is difficult to establish exact numbers at doctors do not have to report cases of MS to a central system.
Although there is no cure for MS, treatment can help manage the disease and slow its progression.
Early intervention offers the best chance against long-term disability. Therefore, it is crucial to recognize the initial symptoms of MS and seek prompt medical attention. Read on to learn more.
Most people with MS experience their first symptoms in their 20s or 30s. Some of the most common early indications include:
The National Institute of Neurological Disorders and Stroke in the United States report that vision problems are often the initial symptom of MS. Inflammation disrupts the vision when it affects the optic nerves.
Possible vision changes include:
- blurred vision
- double vision
- red-green color distortion
- loss of vision
- pain when looking up or to the side
Fatigue and weakness
Most people with MS experience fatigue and weakness. Nerve damage in the spine results in long-term, or chronic, fatigue.
Weakness most commonly affects the legs before extending to other body parts. The symptom may come and go or last for several weeks at a time.
Tingling and numbness
Tingling and numbness are other common early warning signs of MS. These symptoms most often occur in the:
Initially, numbness and tingling may be mild, but they can become more severe over time. Most of the time, these symptoms are not disabling and will come and go without the need for treatment.
Pain and spasms
Up to two-thirds of people with MS worldwide report related pain. A person may experience short- or long-term pain.
Examples of short-term pain include:
- stabbing pain in the face (trigeminal neuralgia)
- a brief, electric shock-like sensation from the back of the head down the spine (Lhermitte's sign)
- burning or stabbing sensations around the body (neuropathic pain)
Chronic pain causes burning, aching, or "pins and needles" sensations. Muscle spasms — sharp, jerking movements of the legs and arms — are also common.
Dizziness and loss of balance
Dizziness and balance problems affect many people with MS. They may experience:
These symptoms can cause people to lose their balance, be clumsy, or struggle to walk.
Less commonly, people with MS experience vertigo, which is the sensation that the surroundings are spinning. This occurs when lesions affect the parts of the brain that maintain balance.
Bladder and bowel issues
The majority of people with MS experience some degree of bladder dysfunction. Bladder issues occur when lesions affect nerve signals that control the bladder and urinary function.
Symptoms typically include:
- increased urinary frequency
- urinary urgency
- difficulty starting urination
- night-time urination (nocturia)
- difficulty completely emptying the bladder
Sexual arousal begins in the central nervous system, when the brain sends messages to the sexual organs.
Damage to these nerves causes some people with MS to notice changes in their levels of sexual desire, sexual activity, and ability to orgasm.
Other symptoms of MS, such as fatigue and pain, may also reduce sexual desire.
Cognitive and emotional changes
Approximately half of all people with MS will notice cognitive changes that affect their:
- ability to concentrate
- abstract reasoning
- attention span
- problem-solving skills
- speed of information processing
Other symptoms that affect people with MS include:
- breathing difficulties
- hearing loss
- speech problems
- trouble swallowing
- walking difficulties
MS is an autoimmune disease that damages the central nervous system. The exact cause is not clear, but genetic and environmental factors likely play a role in its onset.
Factors that increase the risk of developing MS include:
- Age: MS most commonly affects people in their 20s or 30s, although it can occur at any age.
- Sex: The condition affects at least twice as many women as men.
- Family history: The average person has a 0.1 percent chance of developing MS. However, if a close family member has the disease, a person has a 2.5–5.0 percent chance.
- Infection: Several viruses may influence MS, including the Epstein-Barr virus.
- Other autoimmune diseases: People with other autoimmune conditions, such as thyroid disease or type 1 diabetes, have a slightly increased risk of developing MS.
- Geographic region: MS is much more common in temperate climates than sunny regions. Within the U.S., the condition is more common in Northern states.
- Ethnicity: White people, especially those of Northern European heritage, are most likely to develop MS. Those of African, Asian, or Native American heritage are least likely.
- Smoking: People who smoke may have a higher risk of developing MS.
Anyone with early symptoms of MS should consult a doctor without delay. Damage to the central nervous system can occur even before a person experiences symptoms.
Early diagnosis and treatment can provide the best chance of preventing disability.
Many treatments can help slow the progression of MS and alleviate symptoms, such as pain, fatigue, and bladder problems.