The etiology of nonfamilial amyotrophic lateral sclerosis (ALS) remains unknown. Earlier studies have suggested an increase in the incidence of ALS over time. We performed a retrospective analysis of ALS-associated death rates and trends in the United States for 1979-2001 using death records from the national multiple cause-of-death database. The US average annual age-adjusted ALS death rate was 1.84 per 100,000 persons for 1979 through 1998. Most deaths were among adults > or =65 years of age and the median age at death was 67 years. A small overall increase in the death rate was observed primarily between 1979 and 1983, with a subsequent plateau. This slight change in the overall rate reflected apparent increases in the rates among those persons > or =65 years of age, particularly women, and persons in the 20- to 49-year-old age group. The ALS-associated death rate appeared to differ by geographic area, with a higher occurrence among most northern states. Our findings suggest that the epidemiology of ALS-associated deaths in the United States demonstrated small increases in the overall age-adjusted death rate and in the death rates among elderly women and adults 20-49 years of age. Subpopulations at higher risk for ALS were males, whites, persons > or =65 years of age, and residents of northern states. This study provides information for further studies to examine the epidemiology and risk factors associated with ALS.
Copyright 2005 S. Karger AG, Basel.