An impaired sense of smell, or olfactory dysfunction, is a recognized symptom of Alzheimer’s disease and olfactory decline has emerged as an early predictor of the condition. Olfactory dysfunction has also been associated with risk for other forms of dementia and cognitive decline in cognitively healthy older adults. Olfactory identification has shown promise as a screening tool for neurodegenerative conditions but studies of these tests have been limited to Caucasian populations. The Health, Aging, and Body Composition (Health ABC) study recruited cognitively normal, community-dwelling, older (age 70-79) black and white American adults and followed them for 12 years for the development of dementia. Olfactory identification was measured in year 3 of the study. Poor olfaction was significantly associated with risk for dementia among whites, and an association was also seen among blacks. This study, supported in part by NINR, indicates that olfactory identification may be a useful dementia screening tool among black and white American adults.
Yaffe K, Freimer D, Chen H, Asao K, Rosso A, Rubin S, Tranah G, Cummings S, Simonsick E. Olfaction and risk of dementia in a biracial cohort of older adults. Neurology. 2017 Jan 31;88(5):456-462. PMID: 28039314