What is Multiple Sclerosis?
Multiple sclerosis (MS), also known as disseminated sclerosis or encephalomyelitis disseminata, is an inflammatory disease in which the insulating covers of nerve cells (myelin) in the brain and spinal cord are damaged. Damage to myelin causes interference in the communication between your brain, spinal cord and other areas of your body. This condition may result in deterioration of the nerves themselves, a process that’s not reversible. MS takes several forms, with new symptoms either occurring in isolated attacks (relapsing forms) or building up over time (progressive forms). Between attacks, symptoms may go away completely; however, permanent neurological problems often occur, especially as the disease advances.
Symptoms of multiple sclerosis vary, depending on the location of affected nerve fibers. Multiple sclerosis symptoms may include:
Numbness or weakness in one or more limbs
Partial or complete loss of central vision, usually in one eye, often with pain during eye movement (optic neuritis)
Double vision or blurring of vision
Tingling or pain in parts of your body
Electric-shock sensations that occur with certain head movements
Tremor, lack of coordination or unsteady gait
Heat sensitivity is common in people with multiple sclerosis. Small increases in body temperature can trigger or worsen multiple sclerosis symptoms.
Most people with multiple sclerosis, particularly in the beginning stages of the disease, experience relapses of symptoms, which are followed by periods of complete or partial remission of symptoms.
Some people have a benign form of multiple sclerosis. In this form of the disease, the condition remains stable and often doesn’t progress to serious forms of MS after the initial attack.
The Four Courses of Multiple Sclerosis
People with MS can typically experience one of four disease courses, each of which might be mild, moderate, or severe.
Relapsing-Remitting MS
People with this type of MS experience clearly defined attacks of worsening neurologic function. These attacks—which are called relapses, flare-ups, or exacerbations —are followed by partial or complete recovery periods (remissions), during which no disease progression occurs. Approximately 85% of people are initially diagnosed with relapsing-remitting MS.
Primary-Progressive MS
This disease course is characterized by slowly worsening neurologic function from the beginning—with no distinct relapses or remissions. The rate of progression may vary over time, with occasional plateaus and temporary minor improvements. Approximately 10% of people are diagnosed with primary-progressive MS.
Secondary-Progressive MS
Following an initial period of relapsing-remitting MS, many people develop a secondary-progressive disease course in which the disease worsens more steadily, with or without occasional flare-ups, minor recoveries (remissions), or plateaus. Before the disease-modifying medications became available, approximately 50% of people with relapsing-remitting MS developed this form of the disease within 10 years. Long-term data are not yet available to determine if treatment significantly delays this transition.
Progressive-Relapsing MS
In this relatively rare course of MS (5%), people experience steadily worsening disease from the beginning, but with clear attacks of worsening neurologic function along the way. They may or may not experience some recovery following these relapses, but the disease continues to progress without remissions.
Since no two people have exactly the same experience of MS, the disease course may look very different from one person to another. And, it may not always be clear to the physician—at least right away—which course a person is experiencing.
The major scientific theories about the causes of MS include the following:
It is now generally accepted that MS involves an immune-mediated process—an abnormal response of the body’s immune system that is directed against the myelin (the fatty sheath that surrounds and insulates the nerve fibers) in the central nervous system (CNS—the brain, spinal cord and optic nerves).
MS is known tooccur more frequently in areas that are farther from the equator. Epidemiologists—scientists who study disease patterns—are looking at many factors, including variations in geography, demographics (age, gender, and ethnic background), genetics, infectious causes, and migration patterns, in an effort to understand why.
MS is not considered a hereditary disease; however, a number of genetic variations have been shown to increase the risk. The probability is higher in relatives of an affected person, with a greater risk among those who are more closely related. In identical twins both are affected about 30% of the time, while around 5% for non-identical twins and 2.5% of siblings are affected with a lower percentage of half-siblings. If both parents are affected the risk in their children is 10 times that of the general population.
Although there is no known cure for multiple sclerosis, several therapies have proven helpful. The primary aims of therapy are returning function after an attack, preventing new attacks, and preventing disability.
Promoting Function through Rehabilitation
Rehabilitation programs focus on function—they are designed to help you improve or maintain your ability to perform effectively and safely at home and at work. Rehabilitation professionals focus on overall fitness and energy management, while addressing problems with accessibility and mobility, speech and swallowing, and memory and other cognitive functions.
The Role of Complementary and Alternative Medicine (CAM)
CAM includes everything from exercise and diet to food supplements, stress management strategies, and lifestyle changes. These therapies come from various disciplines and traditions—yoga, hypnosis, relaxation techniques, traditional herbal healing, Chinese medicine, macrobiotics, naturopathy, and many others. They are referred to as complementary when they are used in conjunction with conventional medical treatments and alternative when they are used instead of conventional treatments.
Medications for Modifying the Disease Course
The following agents can reduce disease activity and disease progression for many individuals with relapsing forms of MS, including those with secondary progressive disease who continue to have relapses: Aubagio (teriflunomide) Avonex (interferon beta-1a) Betaseron (interferon beta-1b) Copaxone (glatiramer acetate) Extavia (interferon beta-1b) Gilenya (fingolimod) Novantrone (mitoxantrone) Rebif (interferon beta-1a) Tecfidera (dimethyl fumarate) Tysabri (natalizumab).