What is multiple sclerosis?
Multiple sclerosis (MS) is a chronic disease affecting the brain and spinal cord (central nervous system). An autoimmune disease, MS causes the body’s immune system to attack the protective covering around the nerves in the brain and spinal cord. This attack causes inflammation, which disrupts electrical messages between the brain and body. MS can cause permanent damage and nerve deterioration.
The cause of MS is unknown. It is not contagious, nor is it directly inherited. While there is no cure, treatment can help with symptoms and slow its progression. The approximately 200,000 MS cases per year in the United States cause a wide variety of symptoms including pain, fatigue and lack of physical coordination. MS affects every patient differently. Symptoms depend on which nerves are affected and how badly they’re damaged. Some people have such mild symptoms that no treatment is needed. Other MS patients are symptom free most of their lives. Yet other patients have long-term symptoms so severe that they lose the ability to write, speak or walk.
In very rare cases, MS can progress so rapidly that it is fatal. The average life expectancy of MS patients is shortened by about seven years, compared to the general population. Complications of MS plus other medical conditions can shorten lifespan. However, most of these complications are manageable with physical therapy and medication.
Are there different types of multiple sclerosis?
MS is described by how the disease progresses. Four basic types of progression are used to define the disease and plan treatment. The basic types are:
Another condition, called radiologically isolated syndrome (RIS), is useful to identify patients who have MS-like lesions on the brain and/or spinal cord but do not have neurological symptoms. More than half of people with RIS develop MS within 10 years. These patients should be monitored with MRIs and neurological exams to quickly identify changes so early treatment can begin.