Vicious age circle links depression and memory loss, says research

Depression can speed up memory loss in the over-50s because it changes the structure of the brain, according to research.

Scientists at University College London monitored 8268 adults for 16 years to examine the relationship between depressive symp­toms and forgetfulness. Picture: iStock/Getty Images

Depression can speed up memory loss in the over-50s because it changes the structure of the brain, according to research.

Scientists at University College London monitored 8268 adults for 16 years to examine the relationship between depressive symp­toms and forgetfulness. They found that suffering from bouts of depression could hasten memory decline, while in a vicious circle, poor memory in turn worsened depressive symptoms.

The scientists said depression can cause changes in brain structures and lead to high levels of stress hormones, which damage brain cells, contributing to memory decline and even dementia.

They added that treatments for depression, such as antidepressants, could stave off memory loss.

“It is known that depression and poor memory often occur together in older people, but what comes first has been unclear,” said Dorina Cadar of UCL’s Department of Behavioural Science & Health and Brighton and Sussex Medical School, the senior author of the study.

“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.

“It also suggests that interventions to reduce depressive symptoms may help to slow down memory decline.”

The researchers highlighted how depression can cause changes in the brain that may disrupt its ability to reorganise and form new memories, including “neurochemical imbalances” in serotonin and dopamine.

Dr Cadar said: “Depression can cause changes in brain structures such as the hippocampus, which is critical for memory formation and retrieval. Chronic stress and high levels of cortisol associated with depression can damage neurons in these areas.

“A further understanding of mechanisms linking memory decline and depression is crucial for developing targeted interventions aimed at improving mood and slowing cognitive decline in individuals with depression and memory impairment.”

The study, published in the medical journal JAMA Network Open, involved data from the English Longitudinal Study of Ageing, which includes a clinical questionnaire screening for symptoms of depression, such as a low mood and lack of energy, as well as memory tests. The participants had an average age of 64 at the start of the study and were followed for 16 years.

An Australian Institute of Health and Welfare study released in February found one in five Australians had a mental ­disorder. The figure was one in seven in children and adolescents.

Jiamin Yin, lead author of the study, said: “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.

“Conversely, it is also critical to address depressive symptoms among those with memory decline to protect them from developing depression and memory dysfunction.”

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