Previous research suggesting loss of smell function may serve as an early marker of Alzheimer's disease has now been supported by a finding that in genetically engineered mice, loss of smell function is associated with amyloid-beta accumulation in the brain, and that amyloid pathology occurs first in the olfactory region. It was striking how sensitive olfactory performance was to even the smallest amount of amyloid presence in the brain as early as three months of age (equivalent to a young adult).
Loss of smell may predict early onset of Alzheimer's
Reference
Wesson, D. W., Levy, E., Nixon, R. A., & Wilson, D. A. (2010). Olfactory Dysfunction Correlates with Amyloid-{beta} Burden in an Alzheimer’s Disease Mouse Model. J. Neurosci., 30(2), 505-514. Retrieved from http://www.jneurosci.org/cgi/content/abstract/30/2/505
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