The Incidence of Amyotrophic Lateral Sclerosis in Friuli Venezia Giulia, Italy, from 2002 to 2009: A Retrospective Population-Based Study

Background: We conducted a retrospective population-based study to estimate the incidence of amyotrophic lateral sclerosis (ALS) in Friuli Venezia Giulia, Italy, from 2001 to 2009. Methods: Multiple sources were used for case ascertainment: Health databases, archives of the neurology departments and of the regional chapter of the Italian ALS Association. The diagnosis was validated through clinical documentation review. Crude and standardized incidence rates (IRs) per 100,000 person-years were calculated. Results: We identified 262 incident ALS cases, 50.4% men, 4.2% familial. Half of the patients had spinal onset (56.8% in men) and 25.2% bulbar (29% in women). Bulbar onset had a similar frequency in women (31.7%) and men (31.5%) aged 67 or above at diagnosis. The crude IR was 2.72 (95% confidence interval, 95% CI, 2.39-3.05) and the male:female ratio 1.08. The IR peaked in the 65-74 age group, with a second increase in men 85 years and older. The IR standardized to the 2001 Italian population was 2.38 (95% CI 2.13-2.63) and to the 2000 European population 2.58 (95% CI 2.34-2.81). Conclusions: This retrospective study found IRs of ALS in the range of Italian and European prospective population-based registries, suggesting an almost complete case ascertainment.