Understanding alzheimers disease what you need to know easy to read booklet learn about alzheimers a brain disease that causes memory loss and other symptoms find out when to see the doctor and what treatments are available pdf 575 m get paper copy get you are visiting the nia publications ordering portal. Everything you need to know about alzheimers disease medically reviewed by timothy j legg phd crnp written by jaime herndon ms mph mfa updated on may 25 2019 facts. What you need to know what is alzheimer disease alzheimer disease ad is an irreversible brain disorder that results in the gradual loss of memory parts of the brain die and cannot make normal levels of brain chemicals this causes problems with how you think behave and remember things the disease usually starts at about age 65 to 70 years but can start earlier a person usually has ad