Depression at 20, dementia at 80? It was already known that depression in the elderly is associated with a risk of dementia. But it seems that this risk starts much earlier, because being depressed in your 20s is already a risk factor for dementia in old age. According to a study by the University of California in San Francisco (United States), published on September 28, 2021 in the Journal of Alzheimer’s Disease, depression in young adults would have an impact on cognition about ten years later, leading to long-term cognitive decline that could lead to dementia.
Data on 15,000 people
To reach this conclusion, the researchers combined health data from about 15,000 people between the ages of 20 and 89, in order to develop a model with symptoms related to depression at each age and their progression. They then applied this model to 6,000 participants over the age of 70, who were followed annually for almost eleven years. So, they predicted how much depression each of them must have when they are younger. “Normally, we predict ‘ahead’ based on what we observe. Here, we predicted ‘backwards’, using information from the younger participant cohorts to get an estimate of depressive symptoms in older people when they were younger, explains Willa Brenowitz, a mental health epidemiologist at the time. Of aging and author of the study.