We’ve long known of the link between depression and dementia.
Now, a new study pinpoints six depressive symptoms in middle age that can predict dementia more than two decades later.
Dementia diagnoses are projected to skyrocket in the coming years, with new cases expected to reach 1 million per year by 2060 if significant intervention isn’t taken.
For this study, researchers from University College London analyzed data from 5,811 middle-aged participants who were predominantly male and white.
Depressive symptoms were documented with a questionnaire when participants were dementia-free and between the ages of 45 and 69. Participants’ health was tracked for the next 25 years.
During this follow-up period, 10% of participants developed dementia.
Further analysis revealed that participants who were classified as depressed in midlife had a 27% higher risk of developing dementia.
Researchers found that this staggering increase in dementia risk was completely driven by six symptoms in adults younger than 60.
The symptoms are:
- Loss of confidence
- Inability to face up to problems
- Not feeling warmth and affection for others
- Feelings of nervousness, like your nerves are pulled tight
- Dissatisfaction with the way tasks are carried out
- Difficulties concentrating
Specifically, loss of self-confidence and difficulty coping with problems were each associated with a 50% increased risk of dementia.
Comparatively, researchers found that other depressive symptoms, such as low mood, suicidal ideation and sleep issues, had no meaningful, long-term association with dementia.
“Our findings show that dementia risk is linked to a handful of depressive symptoms rather than depression as a whole. This symptom-level approach gives us a much clearer picture of who may be more vulnerable decades before dementia develops,” said lead author Philipp Frank.
The research team noted that symptoms like a loss of self-confidence, difficulty coping with problems and poor concentration precipitate social isolation and a reduction in stimulating experiences, both of which diminish cognitive resilience.
Researchers maintain that focusing on these six key symptoms when treating midlife depression could lead to reduced dementia risk down the line.
“Everyday symptoms that many people experience in midlife appear to carry important information about long-term brain health. Paying attention to these patterns could open new opportunities for early prevention,” said Frank.
The findings were published Monday in The Lancet Psychiatry.
Dementia’s impact extends beyond cognitive decline, as it increases the risk of a range of health issues, including infections, serious falls, cardiovascular problems, malnutrition and depression itself.
“This is a new and important way of considering depression and dementia, and it is more evidence that depression is a wide umbrella and not necessarily one illness,” said study co-author Gill Livingston, chair of the Lancet Commission on dementia prevention.
“There is some limited evidence that treating depression in midlife might reduce later dementia risk, but further research is needed to better understand how best to reduce dementia risk.”
The team acknowledged the limitations of their study and the need for further research to determine if these six telltale symptoms also apply to women and ethnic minorities.
There’s no known cure for dementia, but treatments and therapies can help manage symptoms and potentially slow disease progression.
