Symptoms of depression may flag serious health events in older adults, a new analysis finds
Key points:
- Researchers tracked depressive symptoms, including those that do not meet criteria for depressive episodes, in 19,000 older adults in the ASPREE trial, mostly aged over 70
- Ongoing depressive symptoms were associated with an increased risk of independence-limiting physical disability, cancer, major bleeding and death
- New depressive symptoms were associated with an increased risk of dementia
- Routine screening for depression may help identify older adults at risk of health events
Regular screening for depression in late life may help identify older adults at risk of major health events, a new study in community-dwelling older adults in Australia and the US shows.
ASPREE researchers from Monash University and Deakin University’s Institute for Mental and Physical Health and Clinical Translation (IMPACT) found ongoing depressive symptoms, including those not meeting criteria for major depression, were associated with an increased risk of poorer health – compared to those who were symptom-free.
The study of data from more than 19,000 adults, mostly aged 70 and older in the ASPREE trial, is the largest to investigate the progression and health implications of depressive symptoms in later life.
Lead author IMPACT’s Dr Bruno Agustini said symptoms of depression in older adults are often incorrectly attributed to normal ageing and may go undetected and untreated.
“Regularly screening older adults for depressive symptoms drives better mental health care and closer surveillance of associated physical health factors, potentially improving outcomes for this population” said Dr Agustini.
ASPirin in Reducing Events in the Elderly (ASPREE) clinical trial was a large multi-centre, bi-national study of aspirin and health in older adults, mostly over the age of 70 years. The trial was led by Monash University in Australia, and the Berman Center for Outcomes and Clinical Research in the USA.
The present study, published in Nature Aging, analysed data from 19,110 ASPREE participants collected over an average of five years.
ASPREE participants were generally in good health, were living independently at enrolment into the trial, and were without a history of heart disease, persistent physical disability or dementia. Diagnosed health events captured in the study were independently verified by clinical experts.
Information on depressive symptoms was collected using a validated self-reporting scale at study entry and annually thereafter.
Researchers grouped participants according to the severity of depressive symptoms as: ‘non-depressed’, ‘sub-threshold depression’ (moderate), ‘persistent depression’ and ‘emerging depression’ (initially low, and progressing).
More than 90% of participants did not change groups over the trial period.
Participants with depressive symptoms were observed to have a significantly higher risk of prolonged physical disability, cancer and major bleeding, compared to those in the ‘non-depressed’ group.
Persistent depression was strongly associated with a higher risk of mortality, with participants in this group also more likely to be obese, have multiple health issues, be smokers, drink alcohol and live alone.
In line with other studies, emerging depression was associated with a risk of dementia, suggesting that depression may be an early signal of the disease.
The reason for the association between depressive symptoms and physical illness is unknown.
It is thought that depression may activate stress systems in the body, with the potential to accelerate ageing. Conversely, poor health and physical stress may increase susceptibility to depression and hasten progress.
“Depression might be a truly modifiable factor that when treated, can directly reduce the risk of illness. Or depressive symptoms may be part of other processes driving poor physical health,” said Dr Agustini. “We don’t know. It’s probably a combination of both.”
“Our research indicates the potential health consequences of depressive symptoms for older adults. Regular screening and treatment for depressive symptoms may lead to improved overall health and quality of life.”