Down syndrome is a genetic disease resulting from the presence of all or part of an extra 21st chromosome (trisomy 21). The medical consequences of this extra genetic material are highly variable and may affect the function of any organ system or bodily process. The health aspects of Down syndrome encompass anticipating and preventing effects of the disease, recognizing complications of the disorder, managing individual symptoms, and assisting the individual and his/her family in coping and thriving with the illness.

 

The most common manifestations of Down syndrome are the characteristic facial features, cognitive impairment, congenital heart disease, hearing deficits, short stature, and Alzheimer's disease. Other serious, but less common illnesses include leukemia, immune deficiencies, and epilepsy. While there is evidence pointing to a shortened life expectancy for people with Down syndrome, it is clear that persons with Down syndrome are living longer then they have previously.

 

There are benefits as well as challenges: People with Down syndrome have a reduced risk of developing most kinds of cancer, atherosclerosis (atherosclerosis is a disease affecting arterial blood vessels), or diabetic retinopathy (diabetic retinopathy is damage to the retina caused by complications of diabetes mellitus, which can eventually lead to blindness).

 

Down syndrome can result from several different genetic mechanisms. This results in a wide variability in individual symptoms due to complex gene and environment interactions. Prior to birth, it is not possible to predict the symptoms that an individual with Down syndrome will develop. Some problems are present at birth, such as certain heart malformations. Others become apparent over time, such as epilepsy.