ABSTRACT

Multiple sclerosis (MS) is characterized by inflammation, demyelination, axonal injury and gliosis (scarring) and can involve the brain, spinal cord and optic nerves. The course of MS can be relapsing-remitting or progressive, but typically involves insults that are multiphasic and multifocal (i.e. disseminated in time and location). By conservative estimates, at least 350 000 individuals in the United States have MS1. MS is usually diagnosed between the ages of 20 and 40 and is twice as common in women compared with men. In Western societies, MS is second only to trauma as a cause of neurological disability in early to middle adulthood. Manifestations of MS vary from a benign illness to a rapidly evolving and incapacitating disease requiring profound life-style adjustments. Although attention is typically focused on the physical disability associated with MS, the profound impact of mood disorders on the presentation and prognosis of this autoimmune disease has recently begun to be appreciated2-6. Depression as an early and important clinical manifestation of MS is not a new observation,

although it has taken a century for systematic investigations to be undertaken.