The changing course of multiple sclerosis: rising incidence, change in geographic distribution, disease course, and prognosis.

This review provides a brief update of new research findings on the changing epidemiology, disease course, and prognosis of multiple sclerosis (MS). Evidence not only continues to support the female predominance in incidence and prevalence of the disease but also supports an increase in incidence of MS in geographic areas that were previously considered to be low incidence for the disease. An increased interest in population-based registries and databases will provide more valid epidemiological measures and observational studies conducted in well-defined study populations. Such studies are crucial for an accurate description of both changing prognosis of MS and differential characteristics of the various MS phenotypes.