Do people with Alzheimer’s disease also get depressed?
Scientists have known for a long time that depression and dementia are linked. Especially during the 1970s, when there was a lot of emphasis on so-called “reversible dementia,” it was often held that depression had to be “ruled out” (including by a trial of antidepressants) before dementia could be diagnosed. Now, however, although the jury is still out, many experts feel that being depressed can increase the risk of dementia.
Depression can also exist together with Alzheimer’s disease, including in people who become depressed for the first time when they are diagnosed. It seems two issues are at work here. One is that for some people, the diagnosis of such an illness is enough to trigger depression. The other is that the disease appears to affect brain chemicals causing depression. Exactly how to treat depression in someone who also has Alzheimer’s disease is not clear, but in general, drugs that depress the amount of the brain chemical acetylcholine should be avoided.
For an in-depth, up to date review of this question, it is covered in the chapter by David M. Blass and Peter V. Rabins “Lessons from trials of psychotropic agents in Alzheimer disease” in the book Trial Designs and Outcomes in Dementia Therapeutic Research by Kenneth Rockwood and Serge Gauthier.