DEAR DOCTOR K: My grandmother has Alzheimer's disease. Over the past few years I have watched the disease take a toll on her judgment, memory, even her personality. How does Alzheimer's wreak so much havoc in the brain?
DEAR READER: In the past 25 years, medical science has learned a great deal about what causes Alzheimer's disease. Before that, we basically knew just that the brains of people with this disease, viewed with a microscope, had some unusual features. We knew that the disease caused brain cells to die prematurely, but we didn't know why. Today, I think we are closing in on understanding some major causes (if not all of the causes) of brain cell death.