Multiple sclerosis in Italy. A reappraisal of incidence and prevalence in Ferrara
E. Granieri, S. Malagu, I. Casetta, M. R. Tola, V. Govoni, E. Paolino and V. C. Monetti
Section of Neuroepidemiology, University of Ferrara, Italy.
BACKGROUND: Previous descriptive surveys on multiple sclerosis (MS) in the
province of Ferrara, northern Italy, carried out by our own epidemiological
research group, pointed out that this area was not at low-medium risk for
MS. OBJECTIVE: To verify the morbidity estimates and update the temporal
trend of MS. DESIGN AND METHODS: We used a complete enumeration approach by
reviewing all the possible sources of case collection available in Ferrara
for 1965 through 1993. We included all patients with definite and probable
MS according to the criteria of Poser et al. RESULTS: The mean annual
incidence rate was 2.3 per 100,000 population (95% confidence interval,
2.0-2.6 per 100,000), 3.0 per 100,000 for women and 1.5 per 100,000 for
men. On December 31, 1993, 249 patients (170 women and 79 men) suffering
from definite or probable MS were living in the province of Ferrara, giving
a crude prevalence rate per 100,000 population of 69.4 (95% confidence
interval, 61.2-78.7), 90.8 for women and 46.0 for men. CONCLUSION: The data
confirm that in Ferrara, MS occurs more frequently than previously
suggested by the latitude-related epidemiological model, supporting the
view that northern Italy is a high-risk area for the disease. While the
prevalence rate is much higher than in our previous studies, probably owing
to the increasing survival of the patients because of improving supportive
care, the incidence rates, similar in magnitude to those observed in
high-risk areas of northern and central Europe, have remained relatively
stable over time.
