RESUMEN
The Texas Department of State Health Services extended a prevalence study of multiple sclerosis (MS) in a 19-county area in North Texas to include 3 additional years of data and included a new geographic area with a predominantly Hispanic population (El Paso County). Patients in whom MS was diagnosed by a neurologist, who resided in the study areas, and who had an office visit between 1998 and 2003 were included in the study. The 6-year MS prevalence estimate for the North Texas counties was 71.5 per 100,000, and for El Paso County it was 49.4 per 100,000. In both areas, prevalence estimates were higher for females, age groups 40 to 49 and 50 to 59, and for non-Hispanic whites. These estimates provide valuable information about the epidemiology of MS in Texas and allow for a comparison with national estimates. The results also provide much needed prevalence data for the Hispanic population.