Large study: Depressive symptoms in middle age are associated with dementia risk

Depression in middle age has been found to increase the risk of memory disease later in life. According to a recent study, it is associated with certain symptoms that predict the onset of dementia.

Symptoms include loss of self-confidence, difficulty in dealing with problems, difficulty concentrating, increased mental tension, dissatisfaction with one’s own performance and decreased feelings of attachment.

Among the symptoms that most clearly increased the risk of dementia were loss of self-confidence and difficulty in dealing with problems. Together, they increased the risk by roughly 50 percent.

“Depression can appear in very different ways. We therefore wanted to find out which symptoms actually predict the risk of dementia,” says the professor Mika Kivimäki from the University of Helsinki. He was The Lancet Psychiatry – as supervisor of the study published in the science journal.

“Many people have the same symptoms, but not everyone should get nervous,” Kivimäki reassures.

The connection between symptoms of depression and memory disorders still needs further confirmation. It may also be that cognitive abilities begin to decline first and cause these symptoms.

“The connection between the six symptoms was not very strong, and the majority of those reporting these symptoms did not get sick. Still, the connection is not explained by heredity, lifestyle at the beginning of the study, or heart or metabolic diseases,” says Kivimäki.

Why would the loss of self-confidence and the difficulty of solving problems in particular increase the risk of memory disease?

One explanation may be that they reduce a person’s social connections and search for mental stimulation. They are important for acquiring a cognitive reserve, i.e. a knowledge reserve.

A cognitive reserve is needed when a memory disorder has degenerated the brain in one way or another. Thanks to it, thinking and memory remain at a good level, even if there is degeneration in the brain. The brain, as it were, replaces broken connections.

Memory disease develops over the years. The strength of the research is the 25-year follow-up of a large group of people.

It analyzes more than 5,800 people whose health data can be found in the British Whitehall II database. Kivimäki leads this extensive long-term research at University College London.

At the start of the study, the subjects were on average 55 years old. They had not yet been diagnosed with a memory disorder.

Those who were depressed in middle age had a 27 percent higher risk of later developing dementia if they had multiple symptoms of depression. A total of thirty symptoms were classified, of which the mentioned six stood out in particular.

It can be said that if the subject had the mentioned symptoms under the age of 60, his risk of developing dementia was 1.3-1.5 times higher.

Many other symptoms of depression do not seem to be related to the risk of memory illness, such as sleep disorders, suicidal thoughts or gloom.

Research the factors are University College Londonista, from the University of Helsinki and the French Inserm University.

The material deserves a mention. The Whitehall II study has thousands of data on the same people since 1985. Those followed have been civil servants. There have been more men than women.

Over the course of 40 years, a blood sample has been taken from them eight times and a lot of health information has been accumulated about them. They have answered questionnaires about mental health, for example, and participated closely in the research.