Having depression throughout life may be associated with an increased risk of dementia, a new study suggests. Dementia refers to difficulties with reasoning, judgment and memory due to injuries, diseases or other factors that affect the brain. The study further proposes that depression occurring for the first time in late life may be a precursor to Alzheimer’s disease.
For the study, researchers examined data on more than 13,000 members of the Kaiser Permanente Medical Care Program of Northern California from 1964 to 2009. They focused on two stages of life: midlife, ages 40 to 55, and late life.
Experiencing depressive symptoms at either stage was associated with dementia. Depression from midlife on was associated with triple the risk for vascular dementia, caused by impaired blood flow to brain cells. With late life depression, the risk of Alzheimer’s Disease doubled.
These findings add to the growing body of research on the possible connections between depression and cognitive impairment, dementia and Alzheimer’s Disease.
The burning question is: will treating depression help to maintain cognitive function and delay dementia? The study authors voice that hope and suggest it should be the subject of future research.
Depression Versus Dementia
Dementia and depression have similar symptoms, which makes recognizing and diagnosing either condition more challenging. The Alzheimer’s Society in London offers these pointers:
- People with depression may occasionally complain of forgetfulness, but they will recall the missed information when prompted. By contrast, someone with dementia who is forgetful will often try to cover up memory lapses.
- People with depression can experience impairments in reasoning and memory, but usually the cause is poor concentration. With treatment, memory problems improve. That doesn’t happen with dementia.
- Problems with speech, reasoning, and orientation in time and space are unusual in depression but are common in people with dementia.
Recognizing dementia early on may help preserve quality of life. Treatment with memory-enhancing medications are more likely to be effective at this stage. Also early diagnosis allows time for planning.
Barnes, et al. Midlife vs Late-Life Depressive Symptoms and Risk of Dementia. Archives of General Psychiatry, May 2012.