Depression is a serious mental health issue that can rob us of joy - and years of healthy living. While we know that depressive symptoms can cut down the remaining years of disability-free living (or "healthspan") in older adults, it was unclear exactly which symptoms could be the culprit. Researchers from Tohoku University, the Tohoku Medical Megabank Organization, and the National Institute of Biomedical Innovation, Health and Nutrition have found that different patterns of depressive symptoms are associated with disability-free survival in community dwelling older adults, and that these associations differ between men and women.

This study reveals which symptoms of depression are the most highly linked to a reduced healthspan. Knowing which symptoms are the biggest red flags could help public health sector to form strategic and personalized plans. The study was published online in the Journal of Psychiatric Research on April 25, 2026.

The study included 585 older adults participating in the Tsurugaya Project, a comprehensive geriatric cohort study conducted in the Tsurugaya area of Sendai, Japan. Participants were followed for approximately 18 years, and the researchers examined the occurrence of disability requiring long-term care or death. Depressive symptoms and severity were measured using a combination of standardized tests such as the 15-item Geriatric Depression Scale (GDS-15).

"Undertaking such a long-term follow-up study - spanning almost two decades - is a major undertaking," remarks Ryoichi Nagatomi (Tohoku University). "But doing so gives us away to zoom out and look at changes that might take time to occur, so we get the full picture."

The results showed that men with stronger feelings of "worthlessness" had a significantly higher risk of disability or death, whereas for women, "anxiety" was the bigger risk factor.

"Previous measures focus on total depression score, but our results suggest it may be useful to get a detailed, qualitative look at specific symptoms to understand a patient's risk factors down the line and maybe even tailor preventive support programs to their needs," explains Nagatomi.

These findings suggest that mental health assessment in older adults should consider not only the severity of depression, but also the specific types of depressive symptoms and sex differences. In a rapidly aging society such as Japan, addressing paths towards supporting healthy longevity - such as identifying feelings of worthlessness in older men and anxiety in older women - is particularly important in order to provide support and prolong independent living.