Depression in Older Age May Increase Risk of Dementia
A new study published in the journal Neurology says depression in older age may increase the risk of dementia, though the reason for the connection is not yet understood. Most notably, the researchers were not able to identify whether depression brings on dementia or cognitive decline causes people to become depressed.
“Studies have shown that people with symptoms of depression are more likely to develop dementia, but we haven’t known how the relationship works,” lead study author Robert S. Wilson, PhD, neuropsychiatrist at the Rush Alzheimer’s Disease Center, said in a news release. “Is the depression a consequence of the dementia? Do both problems develop from the same underlying problems in the brain? Or does the relationship of depression with dementia have nothing to do with dementia-related pathology?”
Despite not being able to scientifically prove the cause, the latest research does imply that the link between depression and dementia is independent of dementia-related changes in the brain.
“These findings are exciting because they suggest depression truly is a risk factor for dementia, and if we can target and prevent or treat depression and causes of stress we may have the potential to help people maintain their thinking and memory abilities into old age,” Wilson said.
The study evaluated 1,764 people from the Religious Orders Study and the Rush Memory and Aging Project with an average age of 77 who did not experience thinking or memory problems at the onset of the study. The researchers then tracked the participants’ depression symptoms and thinking and memory skills once a year for eight years.
Once the data had been compiled, the findings showed no link between brain damage and the severity of depression symptoms, however the researchers did note that people who developed mild cognitive impairment were more likely to have a more severe level of symptoms of depression before being diagnosed with cognitive impairment. Importantly, the researchers also saw no change in depression symptoms after diagnoses between healthy participants and those diagnosed with mild cognitive impairment.
The results also showed that individuals with dementia were significantly more likely to experience much worse depression symptoms before they experienced dementia symptoms, but the depression symptoms quickly decreased after dementia developed.