Alzheimer’s Disease and Down Syndrome: What’s the Connection?

Posted by Jeff Durish

Tue, Dec 3, 2013

Much research has been done about both Alzheimer’s disease and Down Syndrome (DS). Although they are very different health issues, medically speaking, there are some striking neurological similarities. Studies of patients with DS could shed some light on the mysteries of Alzheimer’s disease.

Scientists have known for decades now that people with Down Syndrome were much more likely to develop Alzheimer’s disease than the rest of the population. In fact, after a person with DS turns 50, they have a 50% chance of developing the form of dementia. The question remained: why is this so?

As we learn more about both conditions, one glaring similarity is beginning to stand out to some in the scientific community: plaque in the brain, called amyloid-beta, is found in all people with DS and is the cause of the damage of nerve cell connections, or tangles, in people with Alzheimer’s disease.

While in most of the population, these plaques begin to build up later in life (usually after age 50), people with Down Syndrome develop them early on, impairing cognition and behaviour. Because the same changes happen in the brains of people DS, regardless of whether or not they develop Alzheimer’s disease, they are another population scientists can turn to for further research.

Brian Skotko, co-director of the Down Syndrome Program at the Massachusetts General Hospital in Boston, is about to begin a clinical trial of an experimental therapy on Down Syndrome volunteers. The therapy is a drug that is designed to block plaque buildup and introduce extra compounds that nourish cells of all types. He believes that amyloid-beta might be the cause of bad memory and learning difficulties in Down Syndrome, and could improve people with either condition.

Researchers at the Sanford-Burnham Medical Research Institute in Orlando, Florida, have also done similar tests on Alzheimer’s mice. Their conclusion is that both Alzheimer’s disease and Down Syndrome lack a protein that is necessary for neurons to fire correctly. The mice, given additional doses of the protein, made significant improvement cognitive function and behaviour.

Learn more about the trials and studies at NBC News and the NY Times.

There is still so much to learn about Alzheimer’s disease and Down Syndrome, but real answers may be in stock for the not-so-distant future. To learn more about how to care for yourself or someone else with Alzheimer’s disease, click below to download our eBook, Living Well with Alzheimer’s Disease.