Down syndrome is a chromosomal disorder that affects an estimated 1 in 800 births or 5,400 infants in the United States each year. The chance of surviving beyond the first year of life has improved in the past few years, with 90 percent of children with Down syndrome now living past 5 years of age. In the study, "Prevalence of Down Syndrome Among Children and Adolescents in 10 Regions of the United States," published in the December issue of Pediatrics (appearing online Nov. 30), researchers conducted a cross-sectional analysis of infants born with Down syndrome from 10 population-based birth defects registries in the U.S. from 1979 to 2003. During this time, the prevalence of Down syndrome at birth increased by 31.1 percent, from 9.0 to 11.8 per 10,000 live births. The study found that in 2002 the prevalence of Down syndrome among children and adolescents aged 0 to 19 was 1 in 971, or approximately 83,400 children and adolescents living with Down syndrome in the Unites States. These results may be useful in determining the number of affected children and adolescents at the state and community levels, and in policy deliberations related to planning for health and other services for individuals with Down syndrome. Because the number of children with Down syndrome at birth and the average lifespan are increasing, the number of individuals living with Down syndrome in different age groups is likely to increase over the next several years.
