ALS incidence and population aging in Northern Italy

Objective: Data on and increase of the incidence of amyotrophic lateral sclerosis (ALS) are conflicting and reflect the use of differing populations and designs. We investigated the incidence of ALS using data from a large population-based registry (SLALOM) in two three-year periods using the same diagnostic criteria and equal methods of case ascertainment. Methods: The registry is based in Lombardy, a 10 million population area of Northern Italy. Using different sources of cases (hospital discharge and ambulatory records, regional claims and prescription records) from nine Lombardy provinces (population, 5,485,163), all patients with newly diagnosed ALS during the periods 1998-2000 and 2008-2010 were included. Results: A total of 235 and 440 newly diagnosed patients were traced during the two study periods. The corresponding incidence rates were, respectively, 1.61 and 2.72 per 100,000 person-years. Data varied with age, sex and province by a significant increase was found only in men aged 65 through 74 years. Conclusions: Based on our findings, the increased incidence of ALS with time is real and can be largely interpreted as a reflection of the advancing age of the general population.