Incidence of multiple sclerosis in Bagheria City, Sicily, Italy.

We investigated the incidence of multiple sclerosis (MS) in a Sicilian community located at sea level. The study was a retrospective search for MS patients. Incidence was studied in the period from 1 January 1985 to 31 December 1994. We searched for definite MS patients, according to Poser's criteria, among the population resident in Bagheria (Palermo province). There were 25 subjects affected by MS, of which 20 were incident MS patients. The average annual incidence was 4.4 per 100,000 persons (n = 453,385 person-years). The incidence increased over time (1985-1989 = 3.5, 1990-1994 = 5.3). A parallel decrease of the interval between onset and diagnosis of MS was observed (1985-1989, 3.7 years, 95% CI = 1.6-7.3; 1990-1994, 1.9 years, 95% CI = 1.0-3.3). These results confirm that MS is frequent in Sicily.