A new study suggests that a declining sense of smell could be an early indicator of Alzheimer's disease, even before noticeable symptoms appear. Researchers at the University of Chicago Medicine found that individuals experiencing a rapid decline in their sense of smell, while still having normal cognitive function, were more likely to show early signs of Alzheimer's.
The study analyzed data from the Memory and Aging Project (MAP), a long-term study following older adults.
Participants who experienced a rapid decline in their sense of smell were more likely to have smaller gray matter volume in brain regions linked to smell and memory, poorer cognitive function, and a higher risk of developing dementia.
The study also found that the risk from losing smell was similar to that of carrying the APOE-e4 gene, a known genetic factor for Alzheimer's disease.
The researchers plan to further confirm their findings by examining brain tissue for Alzheimer's markers.
This research highlights the importance of paying attention to sensory changes as we age. If future studies confirm these findings, smell tests could become a simple, non-invasive way to detect Alzheimer's disease early.