In the journals
A study published online May 17, 2017, by JAMA Psychiatry found that while depression symptoms later in life were associated with dementia, having symptoms in midlife was not. The findings indicate that depression may not be a risk factor for dementia as previously thought, according to the researchers. In the study, about 10,000 people (two-thirds of them men), ages 35 to 55, were recruited and followed for 28 years. Those who reported chronic or recurring depression symptoms at the study's beginning did not show a significant increased risk of developing dementia by the study's end. However, those who reported depression symptoms within the final 11 years of the study were twice as likely to be diagnosed with dementia.
The researchers said that if depression symptoms were a true risk factor for dementia, there would be an association with people who had symptoms earlier in life and not just later. They concluded that depression later in life instead might be an early sign of dementia.