My first recollection of hearing the two phrases side by side was during a visit to the Anschutz Medical Campus, in Aurora, Colorado in 2015. Some nice folks had obtained permission for me to visit with Huntington Potter, PhD., the Director of the Rocky Mountain Alzheimer’s Disease Center.

I won’t try to elaborate here, but will post this to put a bug in your ear, if you’re interested, in why many neuroscientists seem to speak of some kind of connection. Here is a link to the NIH website. https://www.nia.nih.gov/health/alzheimers-disease-people-down-syndrome

Here is a link to the Alzheimer’s Association https://www.alz.org/alzheimers-dementia/what-is-dementia/types-of-dementia/down-syndrome

Here is a link to where I met Mr. Potter.

http://www.ucdenver.edu/academics/colleges/medicalschool/departments/neurology/Faculty/Pages/potter.aspx