Is It Depression or Dementia?

When Depression Looks Like Alzheimer's Or Another Dementia

Photo © Microsoft
Photo © Microsoft

Depression is a mental disorder caused by chemical imbalances in the brain. When we think of depression, we often think of symptoms like having a depressed mood for several weeks or months and losing interest in things that used to be enjoyable. However, depression can also create cognitive symptoms like difficulty thinking clearly, concentration problems, and trouble making decisions.

When depression creates cognitive symptoms that look like Alzheimer's or another type of dementia, it's often referred to as pseudodementia. Diagnosing pseudodementia is complicated, but a thorough examination can reveal important clues.

Pseudodementia is condition that resembles dementia but is actually due to depression. In pseudodementia, a person may appear confused, exhibit depressive symptoms such as sleep disturbance, and complain of memory impairment and other cognitive problems. However, upon careful testing, memory and language functioning are intact. People with pseudodementia often respond to antidepressant medications.

For instance, people with depression might complain about their memory, but they often do well on mental status exams and other tests that evaluate cognitive function. On the other hand, those with dementia often deny any memory problems but don't do as well on mental status exams and similar tests. Also, a depressed person is less likely to show severe mood swings, whereas someone with dementia shows a wider range of emotions and sometimes makes inappropriate emotional responses (e.g., laughing while others are sad).

The Geriatric Depression Scale (GDS) is a screening instrument used to detect depression among older adults. The GDS should be one of several methods used in an evaluation. Older adults might have depression that looks like Alzheimer's, or they might have both depression and Alzheimer's or another dementia. If depression is detected, it can be treated alongside other disorders, such as Alzheimer's disease.

Depression can be reversed, but treating it can be as complex as treating Alzheimer's. While symptoms don't go away immediately, depression often responds well to a combination of antidepressant medication and psychotherapy. People who have depression may experience relapses, so it's important to find a qualified professional or health care team to treat it, whether or not the depression occurs alongside Alzheimer's.

View Article Sources
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