A new study published in JAMA Otolaryngology-Head & Neck Surgery has found that deficits in the sense of smell, known as olfactory impairment, are significantly associated with increased mortality in older adults. The findings, based on data from over 2,500 participants in the Swedish National Study on Aging and Care in Kungsholmen, suggest that olfactory testing could serve as a valuable early indicator of broader health decline.
The researchers found that each incorrect answer on a 16-item odour identification test was linked to a 6 per cent increase in all-cause mortality risk over six years, and a 5 per cent increase over twelve years. The strongest associations were observed for deaths related to neurodegenerative, cardiovascular, and respiratory conditions.
The study identified dementia as the most significant mediator in the relationship between olfactory loss and mortality, accounting for nearly a quarter of the observed risk. Frailty and malnutrition also played important roles.
"Our findings show that the sense of smell is more than a sensory function - it is a window into overall health and resilience in ageing. Olfactory testing could help identify individuals at higher risk of cognitive and physical decline, long before other symptoms appear," says Ingrid Ekström , Assistant Professor at the Aging Research Center (ARC) , Department of Neurobiology, Care Sciences and Society , and one of the study's lead researchers.
The study has been highlighted in a recent JAMA Medical News article , which underscores the growing recognition of olfactory function as a critical, yet underutilised, biomarker in geriatric care. Experts quoted in the article call for greater integration of smell testing into routine health assessments for older adults, alongside vision and hearing checks.
As the global population continues to age, these findings point to the potential of simple, non-invasive smell tests to support early intervention strategies and improve long-term outcomes in older populations.
