Smell test may diagnose Alzheimer’s early
A person’s inability to identify various odors may be linked to development of Alzheimer’s disease, according to new research.
Scientists at Harvard Medical School and Harvard School of Public Health collected data on 215 elderly individuals, including sense of smell, memory performance and biomarkers of loss of brain cell function. The study’s participants were given a smell identification test and various cognitive tests. The researchers also measured sizes of specific brain structures as well as deposits of beta-amyloid—a protein which accumulates as hard plaques in Alzheimer’s disease.
The researchers found that the adults with a smaller hippocampus—a part of the brain that is important for memory—performed worse in the smell identification test and also had worse memory than those with a larger hippocampus. They also found that the adults with higher levels of amyloid deposits in their brain generally had weaker olfactory functions than those with lower levels of amyloid deposits.
The findings, reported at the Alzheimer’s Association International Conference 2014 in Copenhagen, suggest that smell identification testing could be used to identify adults who are at risk of Alzheimer’s disease, researchers said. They added, however, that further research is needed to determine how effective olfactory testing can be for detecting Alzheimer’s.