NATURAL-HISTORY OF MULTIPLE-SCLEROSIS

Multiple sclerosis (MS) is the most common idiopathic inflammatory dis ease of the central nervous system. The distinction between MS and oth er benign or fulminant inflammatory demyelinating disorders is based o n quantitative, rather than qualitative, differences in chronicity and severity. Primary progressive MS may differ from relapsing-remitting MS in MRI lesion frequency, immunogenetic profile, responsiveness to i mmunosuppressive treatment, and histology. In 60% of patients, MS begi ns as a relapsing-remitting disease and evolves secondarily into a pro gressive neurological illness. Life expectancy is not substantially al tered in patients with MS, particularly in the early years of the illn ess. The rate of suicide has been reported to be increased sevenfold i n MS patients. Up to 40% of patients with attacks severe enough to ren der them nonambulatory may not recover. At 15 years from MS onset, 50% of patients are disabled to the point at which they at least require a cane to walk a half block. Early age at onset, female sex, relapsing -remitting course at onset, and perhaps optic neuritis or sensory symp toms at onset and relatively few attacks in the first two years are as sociated with a favorable course.