WEDNESDAY, June 12, 2024 (HealthDay News) -- Depression and memory declines may be closely linked in older people, new research suggests.

“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," said senior study author Dr. Dorina Cadar, of University College London.

The study suggests that effective depression treatment could help preserve memory function with age, she added in a university news release.

The new findings come from an analysis of data from the ongoing English Longitudinal Study of Ageing, where people are tracked by questionnaires every two years.

In this sample, 16 years of data were collected from nearly 8,300 adults averaging 64 years of age.

In contrast to the finding that memory and depression were closely intertwined, the research did not show a strong relationship between depression and another marker of brain health, verbal fluency.

Cadar, who is a research fellow in dementia at UCL, said it's not surprising that battles with depression could affect memory over time.

“Depression can cause changes in brain structures, such as the hippocampus, which is critical for memory formation and retrieval," she explained. "Chronic stress and high levels of [the stress hormone] cortisol associated with depression can damage neurons in these areas."

The researchers also believe that depression upsets the balance of serotonin and dopamine in the brain, and disrupts the brain's ability to repair and reorganize vital connections.

Memory troubles might also be linked to the tendency in depression to ruminate -- repeatedly thinking about certain things or dwelling on negative feelings.

On the flip side, a life spent dealing with memory lapses could trigger insecurity, frustration and other feelings that can be triggers for depressive episodes, Cadar's group reasoned. Memory troubles might also lead one to more social isolation.

“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 study lead author Jiamin Yin, who has since graduated from UCL and is now a doctoral student at the University of Rochester in New York.

So, if and when depressive symptoms arise, it is "critical" to treat them to prevent folks "from developing depression and memory dysfunction," Yin said.

The findings were published June 11 in the journal JAMA Network Open.

More information

Find out more about treating depression at the Cleveland Clinic.

SOURCE: University College London, news release, June 11, 2024