Frequency of MS in the province of Modena, 1970-1990.

Before 1975 the multiple sclerosis (MS) prevalence rate in Italy ranged from 4 to 21 cases per 100,000 inhabitants. In more recent studies the MS prevalence rate exceeded 30 cases per 100,000. We decided to perform an epidemiological survey in the province of Modena, Northern Italy, in order to clarify whether Italy should be considered as an area at high risk for MS like the countries of continental Europe. The mean annual incidence for the disease for the period 1970-1990 was 1.49 per 100,000, and the prevalence rate was 38.91 per 100,000 on December 31, 1990. These results indicate Modena is a high risk MS area.