Multiple sclerosis (MS) is a chronic, often disabling disease of the central nervous system and is the most common cause of chronic neurological disability in young adults, affecting between 250,000 and 350,000 people living in the U.S. With an average age of 28 at the time of diagnosis, MS disrupts the careers of working-aged individuals, most commonly Caucasian women from northern European backgrounds. MS typically presents with a relapsing-remitting course. However, after a period of time averaging from five to 15 years, most experience a secondary progressive phase where the course changes to either a continuously progressing one or one that progresses between exacerbations (Polman & Uitdehaag, 2000).
MS occurs through a process of progressive destruction of the "white" matter in the nervous system--the myelin sheath that protects the nerves and allows for uninterrupted transmission of nerve impulses. This progressive demyelinization is initially an inflammatory process that ultimately leads to the destruction of the nerve. The initial inflammation is called an "exacerbation" and can often be treated using medications to reduce the residual damage. MS is now thought to be an autoimmune disorder, which develops from a complex interaction of early exposure to multiple viruses and genetic vulnerability. MS is characterized by a variable and complex array of symptoms including physical, sensory, and cognitive changes. These symptoms may vary from day to day and can present challenging barriers to participating in employment (Boyden, 2000; Herndon, 2000).
Several important trends have emerged in the last decade, including changing medical management, closer examination of issues related to employment, and trends in health care systems. These trends necessitate that rehabilitation professionals revisit or update their knowledge. The purpose of this article is to provide an overview of published literature that is pertinent to the employment of people with MS.
Trends in Medical Management
The past decade has brought important changes in medical management of MS. From the perspective of the neurologist, disease management has changed "from nihilism to reasonable optimism" (Comi, Colombo, & Martinelli, 2000). This increased optimism is the result of two important trends. First, improvements in magnetic resonance imaging (MRI) techniques have led to a better understanding of the nature and course of the disease. Second, using drugs that became available during the past decade can alter the course of the disease.
MRI as a Tool for Understanding MS
MRI involves the application of a powerful magnetic field to the body that causes cell nuclei to behave like tiny magnets. The signals are picked up by a very sensitive antenna and forwarded to a computer for processing. A variety of neuro-imaging methods are now available, which when taken together, provide a detailed understanding of the neuropathology associated with MS (Joy & Johnston, 2001). When first developed, MRI helped to identify sub-clinical lesions or lesions which had not yet resulted in apparent deficits leading to earlier diagnosis. More recently, MRI has been used to track changes in the brain over time and monitor the impact of drug treatment. Figure 1 illustrates the typical clinical course of relapsing-remitting and secondary progressive MS. Also noted are clinical and sub-clinical episodes of inflammation (exacerbations) along with the progression of axonal loss over time. Neuro-imaging techniques have allowed researchers to study how lesions evolve and resolve. They have also led to the appreciation that MS is not just a disease of myelin but that over time the brain atrophies and white cell matter between the lesions of MS may also be abnormal.
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The correlation between conventional MRI and the functional status of an individual with MS has been described as "modest" (Miller, Grossman, Reingold, & McFarland, 1998). …