Although symptoms of dementia and depression may seem similar, clinicians should be aware of key differences in order to address each condition properly, experts caution.

Both conditions may lead to slower thinking, decreased concentration, confusion and difficulty remembering, notes psychiatrist William Coryell, M.D. But older adults with depression may complain bitterly about memory loss and yet remember important current events or personal matters. In contrast, people with dementia often deny that they’re forgetful. 

In addition, depressed older adults regain their mental function when treated. People with dementia do not, Coryell writes in Merck Manuals.

For these reasons, clinicians should routinely ask older adults about their mood, Coryell advises. Other signs to watch for include subtle changes in personality, especially lack of enthusiasm and spontaneity, loss of sense of humor, and new forgetfulness.

Once diagnosed, depression can be successfully treated, Coryell reminds. Selective serotonin reuptake inhibitors are the antidepressants most commonly used to treat older adults with the disease. This class of drugs is relatively less likely to cause side effects, he said.

Coryell’s report on aging and depression is published in Merck Manual Consumer Version.