Highlights & Basics
- Down syndrome is the most common genetic cause of cognitive or intellectual disability, with an incidence of 1 in 800-1000 births worldwide.
- Characteristic physical features include brachycephaly with a flat occiput; epicanthal folds and upslanting palpebral fissures; Brushfield spots in the iris; low nasal bridge; low-set ears; broad neck; and small hands with transverse crease.
- Individuals with Down syndrome have a higher frequency of congenital and acquired medical conditions, including congenital heart defects and audiologic, vision, gastrointestinal, hematologic, and thyroid issues.
- Global developmental delay is common; however, cognitive abilities vary greatly, with IQ typically ranging from mild to moderate intellectual disability. Behavioral difficulties, if present, tend to be age-related (e.g., hyperactivity and impulsiveness in younger children; withdrawal and anxiety in older adolescents and adults).
- Early interventional therapies (e.g., speech therapy, physical therapy, occupational therapy) and individualized educational programs/resources are essential to support the development of a person with Down syndrome.
Quick Reference
History & Exam
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Citations
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