Incidence of the Guillain-Barré syndrome in Ferrara, northern Italy, 1981-1987.

The few incidence estimates on Guillain-Barré syndrome (GBS) in Italy indicate rates lower than the values provided by other previous non-Italian population-based studies. The latter range from 0.6 to 1.9 cases per 100,000 population per year. To verify whether Italy may be considered a low-risk area for GBS we studied the incidence of the disease in Local Health Unit No. 31 (USL 31) of Ferrara, Northern Italy (mean population 180,701 inhabitants) for the years 1981-1987. The annual incidence rates were stable during this period with an average incidence of 1.26 cases per 100,000 population per year. No significant difference was found for urban or rural residence and there was no significant seasonal clustering. In 37.5% of the series an antecedent infection was recorded within 4 weeks before GBS onset. The survey seems to support the hypothesis of a homogeneous distribution of GBS in space and time and does not support the notion that GBS is less common in Italy than elsewhere.