Depression and memory are closely related, with both seeming to affect each other, according to new research.
A recent study published in JAMA Network Open tracked more than 8,000 participants in the English Longitudinal Study of Aging over 16 years and found a connection between depression and poor memory, highlighting the need for regular monitoring of older adults with depression or memory loss.
“Our study shows that the relationship between depression and poor memory cuts both ways, with depressive symptoms preceding memory decline and memory decline linked to subsequent depressive symptoms,” senior author Dorina Cadar, PhD, of the University College of Lone and Brighton and Sussex Medical School, said in a statement. “It also suggests that interventions to reduce depressive symptoms may help to slow down memory decline.”
The research team suggested that depression might affect memory due to depression-related changes in the brain such as neurochemical imbalances, structural changes in regions involved in memory processing, and disruptions in the brain’s ability to reorganize and form new connections.
Memory decline also could be attributed to psychological factors, including dwelling on negative feelings, the researchers said, adding that people experiencing memory lapses can feel frustrated and lose confidence, which can trigger depression and lead to social isolation.
“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 wrote.
Depression, Cadar said, can cause changes in brain structures critical for memory.
“Chronic stress and high levels of cortisol associated with depression can damage neurons in these areas,” Cadar said. “However, a further understanding of mechanisms linking memory decline and depression is crucial for developing targeted intervention aimed at improving mood and slowing cognitive decline in individuals with depression and memory impairment.”
Although subtle cognitive decline is common in older adults, those who also have depression could see an eventual decline to mild cognitive impairment or dementia, according to the study. The authors noted that due to the “high underdiagnosis” of depression, a significant percentage of older adults are left untreated, which could lead to significant cognitive decline over time.
“These findings underscore the importance of monitoring memory changes in older adults with increasing depressive symptoms to identify memory loss early and prevent further worsening of depressive function,” said lead author Jiamin Yin, a doctoral student at the University of Rochester, Rochester, NY. “Conversely, it is also critical to address depressive symptoms among those with memory decline to protect them from developing depression and memory dysfunction.”
The investigators said that the extended follow-up period for the study highlights the need for regular monitoring of older adults with depression or memory loss. This monitoring could allow for the early detection of changes as well as intervention strategies to slow the memory decline associated with dementia and improve overall psychological well-being.
The study was supported by the National Institute on Aging, the Economic and Social Research Council, the National Institute for Health and Research, Alzheimer’s Society UK and Alzheimer’s Research UK.
