Down Syndrome (Chronic Health Aspects)

Down Syndrome (Chronic Health Aspects) is indexed under Pediatric-Onset Chronic, Genetic/Chromosomal. Also known as trisomy 21.

US prevalence

~200,000 people in the United States Source: MedlinePlus Genetics (NLM), Down syndrome, frequency section last updated June 1, 2020. This figure comes from a professional society, registry, or study rather than a federal source. Label: REPORTED.

ICD-10-CM codes

Q90

Typical onset

Present at birth; median lifespan now ~60

Course

lifelong

Body systems

neurological, cardiovascular, endocrine, immunologic

Sex differences

Slightly more common in males

Racial and ethnic differences

Similar incidence; disparities in healthcare access

What this page does not establish

These figures describe populations, not individuals, and none of them is a diagnosis or a treatment recommendation. Prevalence estimates are approximate and reflect published ranges. Disparity figures are reported patterns, not causes.

Taxonomy last reviewed 2026-05-19. Each figure on the interactive page carries its own source and retrieval date, which can be later than this review.

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