Alzheimer’s Seen on Scans Decades Before Dementia, Study Shows

Abnormal deposits in the brain thought to trigger Alzheimer’s disease can be detected decades before the memory-robbing illness ensues, a finding that will help guide future treatments, researchers in Australia said.

Doctors at Melbourne’s Austin Hospital followed 200 seniors, including people with Alzheimer’s disease and mild cognitive impairment, for more than three years to chart any decline in cognition and brain size against the deposition of abnormal protein in their brains. They found it takes about 20 years for the deposits, known as amyloid beta, to lead to dementia.