About the Study

Why is this research being done?

Alzheimer’s Disease (AD) is a common problem in older adults. About 1 in 9 people who are 65 years old or older will get AD. People with AD have changes in their brains that make it difficult to remember and do things that are a part of everyday life. AD gets worse as time goes on.

Young woman testingIn AD, changes can start in the brain 15-20 years before the problems with memory and functioning begin. If we can tell if someone is at risk – before changes in the brain cause problems – we might be able to help prevent AD or make the problems less severe. Right now, we do not know if someone has AD until the problems start to show.

We want to find a way to tell if someone is at risk (might get this disease) before these problems begin. We think we can learn who is at risk by doing the following things:

  • study biomarkers (things we can measure about the ways the body works)
  • look at genetic profiles (looking at parts of genes)
  • learning about family history (if relatives had AD or other problems)
  • look for early changes in the brain (called neuropathology).

Finding out who is at risk is a first step in learning how we might prevent AD.

AD researchers are very interested in learning more about adults with Down syndrome. Everyone with Down syndrome has an extra 21st chromosome. This chromosome tells the body to make a protein (called amyloid protein). We think that making too much of this protein may cause changes in the brain. Because people with Down syndrome have an extra 21st chromosome, their bodies may be making extra amyloid protein. Therefore, people with Down syndrome have an important role to play in helping researchers understand AD.

How does AD develop? This is what we think.

  • Extra amyloid protein builds up in parts of the brain. We call these “amyloid plaques.” When there is too much of this, parts of the brain may shrink and change. Also, some parts of the brain cannot “talk” to other parts of the brain anymore.
  • Another protein, (tau) appears and forms tangled fibers in the brain. These tangles prevent parts of the brain from getting nutrients from blood to stay healthy. This leads to more changes in the brain.
  • After a while, problems with memory and doing everyday things start to show.

What we can do now?

We can now tell if someone has amyloid plaques and tangles a long time before there are problems by using PET scans. We can also study changes in brain structure (i.e., shrinking) as well as connections between areas of the brain (how parts of the brain “talk” to each other) by using MRI scans. Also, there are new tests to look at possible genetic factors that might help us learn who has the greatest chance of developing AD. Some adults with Down syndrome develop AD in their 40’s, some in their 50’s and some in their 60’s. This research can help us learn about factors that can actually reduce the chance of developing AD.

Our plan is to invite a large group of adults with Down syndrome to participate in this research project. We hope to have 180 individuals with Down syndrome, their caregivers, and 40 siblings of the adults with Down syndrome participate across four different research sites. We will look at the following:

  1. Information from MRI scans (including brain thickness, brain blood flow, and how well parts of the brain are connected or “talk” to each other);
  2. Information from PET scans (including the amount of amyloid plaques and tangles as well as how energy [called sugar glucose] is used in the brain);
  3. Information from blood tests (which will help us to learn about genes and how fats and proteins in the body might be related to functioning).
  4. We will compare this information with any changes that participants have with how they think (cognition) and do everyday things (functioning). This will help us find out which biomarkers might be related to AD.

Who to contact about participating?

Please see our Study Eligibility link on this website to choose the research site closest to your home to inquire about participation.

Woman with DS testing