Epidemiology and clinical features of amyotrophic lateral sclerosis in Ireland between 1995 and 2004

Background: We conducted a prospective, population based study to examine trends in incidence and prevalence of amyotrophic lateral sclerosis (ALS) in Ireland from 1995 to 2004. Methods: The Irish ALS Register was used to identify Irish residents diagnosed with ALS between the 3 year period from 1 January 1995 to 31 December 1997 and the 3 year period from 1 January 2002 to 31 December 2004. Results: 465 Irish residents were diagnosed with ALS during the study periods. The annual incidence rate of ALS in Ireland remained stable over this time (2.0 cases per 100 000 person-years; 95% CI 1.9, 2.2). Median survival of Irish ALS patients was 16.4 months and did not change during the study period. Demographics and clinical features of the incident and prevalent Irish ALS cohorts were markedly different.