It has only recently been recognized that older people with Down's syndrome (DS) are at greater risk of developing Alzheimer's disease. There are over 350,000 people in the USA who have been diagnosed with this syndrome. It is a genetic disorder in which a chromosome, known as trisomy 21, is abnormal.
The main reason for not previously recognizing DS as a significant risk factor for Alzheimer's is life expectancy. In the 1920s, life expectancy for people with DS was just 9 years. This...
