Mortality and Cancer Incidence Among Individuals With Down Syndrome

Abstract

DOWN SYNDROME (DS) occurs in 1 of every 800 to 1000 live births^1,2 and is associated with trisomy of chromosome 21, except in rare instances of chromosome 21 translocation (4%-5% of all cases) or mosaicism (2%-4%).^1,3 Individuals with DS have an increased risk of developing acute leukemia^4-6 and excess mortality due to infectious agents, congenital anomalies, and other conditions.^1,3 Evaluation of cancer risks and the mortality experience of individuals with DS is important for their clinical care and for the early detection of associated diseases. Large cohort studies of DS have been rare, however, and often include only institutionalized individuals, who may not represent the more general DS population. Thus, although many conditions are reported to occur excessively among individuals with DS,^7,8 epidemiologic evidence in support of some associations has been limited.