Scott Landes
Professor of Sociology, Syracuse University
Background and Significance: Over the past 50 years, the age of death form people with Down syndrome in the United States has improved markedly, from an average age at death of 25 in 1983, to 49 in 1997, to 56 in 2017 [39,40]. The increase in longevity for this population is typically ascribed to improvements in early intervention efforts, as well as social supports and medical care for people that often coincided with a transition away from institutional and toward community-based supports [41,42]. With the advent of people with Down syndrome now living into and beyond their 40s, research has documented high rates of early onset Alzheimer’s disease among this population, with some researchers claiming that a majority of individual’s with Down syndrome exhibit neuropathological characteristics of Alzheimer’s disease by age 40 [43-47].
Three studies utilize US death certificate data to document that adults with Down syndrome have higher rates of death from Alzheimer’s disease and or dementia that adults in the general population [40, 48, 49], with the most recent reporting adults with Down syndrome were 25 times more likely to die from these diseases [49]. While informative, there are limitations to this research that need to be addressed. The first is that all three studies rely on analysis of the underlying cause of death, as opposed to conducting broader analysis o multiple cause of death. Thus, while they accurately identify that people with Down syndrome were more likely to have Alzheimer’s/dementia identified as their underlying cause of death, they do not address whether people with Down syndrome were more/less likely to have been diagnosed with Alzheimer’s disease by their time of death. This is an important distinction. As people with Alzheimer’s disease can die from various other diseases [50], focusing solely on the underlying cause of death leads to underestimates of the prevalence of this disease at the time of death that may vary between people with/without Down syndrome. In comparison, utilizing multiple cause of death files, which provide information on comorbidities present at the time of death, would provide a more accurate accounting of the prevalence of Alzheimer’s disease among both populations at the time of death. In addition, analysis of multiple cause of death files would allow for examination of whether causes of death are similar of different among people with and without Down syndrome who have Alzheimer’s disease, an important research question that has not been addressed to date.
Aim 1: To analyze differences in the prevalence of Alzheimer’s disease among people with and without Down syndrome at the time of death.
Aim 2: To document causes of death among people with and without Down syndrome who had Alzheimer’s disease reported on their death certificate.