Amyotrophic lateral sclerosis mortality in the United States, 1979-2001

Abstract

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.