Multiple Sclerosis

What is Multiple Sclerosis?

Multiple sclerosis or MS is a disease that affects the brain and spinal cord resulting in loss of muscle control, vision, balance, sensation (such as numbness) or thinking ability.

With MS, the nerves of the brain and spinal cord are damaged by one's own immune system. Thus, the condition is called an autoimmune disease.

Autoimmune diseases are those whereby the body's immune system, which normally targets and destroys substances foreign to the body such as bacteria, mistakenly attacks normal tissues. In MS, the immune system attacks the brain and spinal cord, the two components of the central nervous system. Other autoimmune diseases include lupus and rheumatoid arthritis.

The central nervous system is made up of nerves that act as the body's messenger system. Each nerve is covered by a fatty substance called myelin, which insulates the nerves and helps in the transmission of nerve impulses, or messages, between the brain and other parts of the body. These messages control mulking and talking.

MS gets its name from the buildup of multiple scleroitic plaques, such as scar tissue (sclerosis) in the brain and/or spinal cord. The scar tissue or plaques form when the protective and insulating myelin covering the nerves is destroyed, a process called demyelination. Without the myelin, electrical signals transmitted throughout the brain and spinal cord are disrupted or halted. The brain then becomes unable to send and to receive messages. It is this breakdown of communication that causes the symptoms of MS.

Although the nerves can regain myelin, this process is not fast enough to outpace the deterioration that occurs in MS. The types of symptoms, severity of symptoms, and the course of MS vary widely, partly due to the location of the scar tissue and the extent of demyelination.

According to the National Multiple Sclerosis Society, the condition affects approximately 400,000 Americans and is, with the exception of trauma, the most frequent cause of neurological disability beginning in early to middle adulthood.

MS is two to three times as common in females as in males and its occurrence is unusual before adolescence. A person has an increased risk of developing the disease from the teen years to age 50 with the risk gradually declining thereafter.

What Causes MS?

No one is sure what causes the body's immune system to go awry. Some scientists believe that it is a combination of genetics and something in the environment to which the person was exposed to early in life.

What Are the Symptoms?

Symptoms vary from person to person and can change over time in the same person. The most common early symptoms include:

• Muscle weakness
• Decreased coordination
• Blurred or hazy vision
• Eye pain
• Double vision

As the disease progresses, symptoms may include muscle stiffness (spasticity), pain, difficulty controlling urination or difficulty thinking clearly.

How Is MS Diagnosed?

Making the diagnosis of MS isn't easy because the symptoms are vague and often fleeting. Factors that a health professional considers are:

• Two or more isolated episodes of symptoms that could be caused by MS. The episodes must last at least 24 hours and occur a month apart.
• MRI test showing the areas of demyelination (lesions)

How Is MS Treated?

There are a variety of medications available that can reduce the frequency and severity of MS symptoms in some people with MS. Some drugs can also slow the progression of certain types of MS.

Recognizing Multiple Sclerosis

Multiple sclerosis symptoms generally appear between the ages of 20 and 40. The onset of MS may be dramatic or so mild that a person doesn't even notice any symptoms until far later in the course of the disease.

The most common early symptoms of MS include:

• Tingling
• Numbness
• Loss of balance
• Weakness in one or more limbs
• Blurred or double vision

Less common symptoms of MS may include:

• Slurred speech
• Sudden onset of paralysis
• Lack of coordination

As the disease progresses, other symptoms may include muscle spasms, sensitivity to heat, fatigue, changes in thinking or perception, and sexual disturbances.

• Fatigue. This is the most common symptom of MS. It is typically present in the mid afternoon and may consist of increased muscle weakness, mental fatigue, sleepiness, or drowsiness.
• Heat sensitivity. Heat sensitivity (the appearance or worsening of symptoms when exposed to heat, like a hot shower) occurs in most people with MS.
• Spasticity. Muscle spasms are a common and often debilitating symptom of MS. Spasticity usually affects the muscles of the legs and arms, and may interfere with a persons ability to move those muscles freely.
• Dizziness. Many people with MS complain of feeling "off balance" or lightheaded. Occasionally they may experience the feeling that they or their surroundings are spinning; this is called vertigo. These symptoms are caused by damage in the complex nerve pathways that coordinate vision and other inputs into the brain that are needed to maintain balance.
• Impaired thinking. Problems with thinking occur in about half of people with MS. For most, this means slowed thinking, decreased concentration, or decreased memory. Approximately 10% of people with the disease have severe impairment that significantly impairs their ability to carry out tasks of daily living.
• Vision problems. Vision problems are relatively common in people with MS. In fact, one vision problem, optic neuritis, occurs in 55% of people with the condition. Most vision problems do not lead to blindness.
• Abnormal sensations. Many people with MS experience abnormal sensations such as "pins and needles," numbness, itching, burning, stabbing or tearing pains. Fortunately, most of these symptoms, while aggravating, are not life-threatening or debilitating and can be managed or treated.
• Speech and swallowing problems. People with MS often have swallowing difficulties. In many cases, they are associated with speech problems as well. They are caused by damaged nerves that normally aid in performing these tasks.
• Tremors. Fairly common in people with MS, tremors can be debilitating and difficult to treat.
• Difficulty walking. Gait disturbances are amongst the most common symptoms of MS. Mostly this problem is related to muscle weakness and/or spasticity, but having balance problems or numbness in your feet can also make walking difficult.

Other rare symptoms include breathing problems and seizures.

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