Using National Death Index (NDI) Data to Identify Individuals with Amyotrophic Lateral Sclerosis (ALS) and Vital Status of People in the National ALS Registry

Amyotrophic Lateral Sclerosis (ALS, Lou Gehrig's disease), is a rapidly fatal motor neuron disease (MND) that causes progressive degeneration in both the upper and lower motor neurons. The ALS Registry Act, passed in 2008, created the National ALS Registry in order to better describe the prevalence and incidence of ALS in the United States. We identified ALS cases from the years 2001 – 2005 in national health databases (Centers for Medicare and Medicaid Services (CMS), Veterans Health Administration (VHA) and Veterans Benefits Administration (VBA)) using an algorithm developed through a group of pilot projects We found 16,226 individuals who definitely had ALS, and an additional 22,096 individuals who possibly had ALS. We compared these two groups of with the National Death Index (NDI) [2001-2008] to determine their vital status, as well as to determine if those identified as possibly having ALS could be classified as definite ALS cases and verify the vital status of the definite cases. 12,393 definite ALS cases, were deceased by the end of 2008. Of the possible ALS cases, 14,588 were deceased. The death certificate of 9,227 (63%) possible cases mentioned MND and provided enough additional information allow classification as definite ALS cases. Using the national databases and the NDI we identified a total of 25,453 ALS cases during 2001 – 2005. The use of NDI to supplement the national health databases resulted in an increase of more than 50% in the number of definite cases of ALS identified in 2001 – 2005.