Depression During Young Adulthood Linked To Memory Issues In Midlife

People who experienced prolonged depressive episodes during their young adulthood stage (18 to 25 years) are at a higher risk of suffering from memory problems in midlife, according to a recent study published in the American Academy of Neurology’s journal, Neurology®.

In the institute’s press release, study author Leslie Grasset from the University of Bordeaux, France, said: “Especially for Black adults, prolonged exposure to elevated depressive symptoms in young adulthood has a negative effect on thinking and memory in middle age. The processes that lead to dementia begin long before signs of the disease become apparent, and previous research has shown that Black adults have a higher risk of dementia than white adults.”

Grasset and colleagues enrolled 3117 people in the study. While 47% were Black, the other 53% identified as white. Their mean age was 30. Over a span of two decades, the researchers evaluated them for depressive systems every five years. This involved making each study participant complete questionnaires on whether or not they had a normal appetite, sleeping patterns, and/or issues related to being able to concentrate, along with any mood issues like feeling lonely, sad, or worthless.

The researchers then labeled their symptoms as either “low”, “medium decreasing”, “persistently medium”, or “high increasing.” They observed that in the high-increasing group, 70% of the participants were Black and another 52% of those in the persistently medium group were also Black.

“Having more depressive symptoms may be due to inequalities in socioeconomic resources such as housing and income, as well as access to health care and treatment. Racial inequalities should be accounted for when designing interventions to reduce a person’s risk of dementia,” Grasset added. “Our results suggest that Black adults are not only more likely to experience worse depressive symptoms trajectories, but these symptoms may lead to worse repercussions on thinking and memory as early as middle age,” said Grasset. “This may help explain some of the disparities in dementia risk at older age.”

Previous studies have also found an association between depressive symptoms and memory problems. A 2024 JAMA Psychiatry study of 8,268 people also reported that cognitive decline and depressive symptoms often occur simultaneously among older adults. And also that significant memory loss could trigger depression.

In their JAMA study, lead author Dorina Cadar, a senior lecturer in dementia and neuro-epidemiology at the University of Sussex, and colleagues wrote: “Cognitive decline and depressive symptoms share some common features and regularly co-occur among older adults. Depression in early life was shown to be a risk factor for dementia, and depression in later life can be considered a prodrome of dementia. In contrast, cognitive dysfunction or dementia could also be attributable to depressive symptoms. This indicates that these are not mutually exclusive and that there may be a bidirectional association.”

“We found that higher depressive symptoms were associated with poorer baseline memory and faster memory loss over time, which was consistent with previous studies. Moreover, having higher depressive symptoms is associated with reduced capability of self-regulation, which leads to a greater chance of unhealthy behaviors that have been shown as risk factors for cognitive impairment,” they added.