THE INCIDENCE OF GUILLAIN-BARRE-SYNDROME IN FERRARA, ITALY - IS THE DISEASE REALLY INCREASING

The Guillain-Bare syndrome (GBS) incidence has been updated in the are a of the Local Health District of Ferrara, Unita Sanilaria Locale n. 3 1 (USL 31), Northern Italy, (where a previous survey found an average annual incidence of 1.26/100 000 population) in order to verify a supp osed increase in GBS occurrence. The updated mean annual incidence ove r the years from 1981 to 1993 (average resident population: 177 235 in habitants) was 1.87/100 000 population (1.66/100 000 when age-adjusted ). The rate increased progressively in the four subsequent time interv als into which the study period was subdivided (from 1.09/100 000 in t he years 1981-1984 to 2.73/100 000 in the years 1991-1993) with a sign ificant temporal variation (0.025 < p < 0.05). The incidence was highe r in the urban centres than in the rural zone of USL 31 (2.22/100 000 and 1.10/100 000; 0.025 < p < 0.05) and an increase of GBS risk in the urban area was found. The incidence showed an increase in the oldest age groups of the study population. These findings seem to confirm a s light increase of GBS risk in the area of Ferrara with particular refe rence to urban centres and elderly people.