Epidemiology of ALS in Italy: a 10-year prospective population-based study

OBJECTIVE: To describe the temporal patterns of incidence and demographic characteristics of amyotrophic lateral sclerosis (ALS) in Piemonte and Valle d'Aosta, Italy, in the 10-year period 1995 through 2004. METHODS: The Piemonte and Valle d'Aosta Register for ALS (PARALS) is a prospective register collecting all cases of ALS incident in two regions of northwestern Italy (population: 4,332,842) since 1995. The cases are identified using several concurrent sources. ALS diagnosis is based on El Escorial criteria. RESULTS: During the 10-year period of observation, 1,347 residents in the study area were diagnosed with ALS. In 1,260 of these cases, a diagnosis of definite or probable ALS was made at presentation or during the follow-up. The mean annual crude incidence rate was 2.90/100,000 population (95% confidence interval [CI], 2.72 to 3.09). The crude prevalence rate (December 31, 2004) was 7.89 (95% CI, 7.09 to 8.75)/100,000 population. According to the capture-recapture estimation, 27 patients were unobserved, thus increasing the annual observed crude incidence to 2.96/100,000 population. The incidence rate did not show any relevant variation during the 10-year period of the study and was constantly higher among men. The demographics and clinical features did not change between the 1995-1999 and the 2000-2004 cohorts, with the notable exception of the mean time delay from onset to diagnosis, which was significantly decreased in the last 5-year period. CONCLUSIONS: In the examined decade, the incidence of amyotrophic lateral sclerosis in Italy has been stable, and the clinical and demographic characteristics of the patients have shown no relevant modifications.