Wingerchuk (2011) describes multiple sclerosis (MS) as an inflammatory demyelinating disease. The National MS Society study estimates almost 1 million (913,925) people in the US are living with MS. This is double the previous estimate. Data sources from health claims from private and public insurers used in a recent study improved the accuracy of the prevalence of MS (Culpepper, et al, 2019). The following are descriptions of significant factors:

MS is often, but not always, a progressively debilitating disease. It is usually experienced as periods of exacerbation followed by partial remission of symptoms. Affected individuals experience a broad range of symptoms which vary due to the site and extent of the CNS involvement. Symptoms may include temporary or permanent cognitive, sensory and motor deficits that can significantly limit independent activities of daily living.

Historically, during the mid-1880's, Jean Martin Charcot described a disorder characterized by multiple patches or plaques of sclerosed (scarred) areas scattered throughout the CNS (brain, spinal cord and cranial nerves). Modern techniques reveal these plaques as areas of inflammation, demyelination and axonal injury.

Magnetic resonance imaging (MRI) is the primary tool used to diagnose MS. MRI is able to identify and quantify the multiple round or ovoid lesions which characterize MS. MRI studies have correlated the cumulative volume of affected tissue with prognosis.

Currently there is no way to prevent or cure MS. The goal of multiple sclerosis therapy is to alter its natural course by:

These issues and more about the care of the patient with MS are described in depth in the following sections of this course.


Compston, A & Coles, A. (2008). Multiple sclerosis. Lancet. 372(9648), 1502-17.

Culpepper, W. J., Marrie, R. A., Langer-Gould, A., Wallin, M. T., Campbell, J. D., Nelson, L. M., et al. (2019). Validation of an algorithm for identifying MS cases in administrative health claims datasets. Neurology. 92 (10). (open access)

Wallin, M. T., Culpepper, W. J., Campbell, J. D., Nelson, L. M., Langer-Gould, A., Marrie, R. A., et al. (2019). The prevalence of MS in the United States. Neurology. 92(10).

Wingerchuk, D.M. (2011). Environmental factors in multiple sclerosis: Epstein-Barr virus, vitamin D, and cigarette smoking. Mt Sinai J Med. 78(2), 221-30.