- Between 40 to 60% of all infants with Down syndrome have some type of heart defect.
- Hypotonia (low muscle tone) is another common feature, which is the cause of not only delayed gross motor development like crawling and walking, but also constipation and gastroesophageal reflux.
- Seizures occur in 5 to 10% of people with Down syndrome.
- Those with Down syndrome are at greater risk for leukemia, sleep apnea, hypothyroidism, celiac disease and diabetes.
- The prevalence of autism or autistic spectrum disorders is estimated to be between 5 and 7%.
- Atlantoaxial instability (AAI), which is caused by excess movement between the first and second vertebrae in the neck, occurs in approximately 15% of youths and causes a potential risk of spinal cord damage.
People with Down syndrome are active participants in the community; schools, jobs and leisure activities. Some live with family, some with friends, and some independently.