In Odor to Tell

Someday doctors may be able to screen for Alzheimer’s using a simple scratch and sniff test, according to two Columbia University studies.

Dr. William Kreisl, a neurologist at Columbia University, and a team of researchers studied 84 people in their 60s and 70s, including 58 with memory problems indicative of early Alzheimer’s. Participants took the University of Pennsylvania Smell Identification Test, or UPSIT.¹ The UPSIT is a test featuring a different “scratch and sniff” strip on each page of a booklet, including familiar smells such as coffee and cinnamon. Those who scored low on the test (less than 35) were three times more likely than other people (those who scored higher than 35) to experience memory decline.

The other study followed 397 people without dementia, whose average age was 80 at the start, for over 4 years. The study found that low scores on the UPSIT test were a strong predictor of the likelihood of dementia.²

Odor tests may be effective because areas of the brain that control the sense of smell are among the first to be affected by Alzheimer’s disease.

Such an odor test is a non-invasive, less-costly alternative to PET scans and spinal taps, presently used to spot Alzheimer’s in its earliest stages.  While there is no cure for Alzheimer’s, detecting and treating the disease earlier could help slow cognitive decline.

Sources:

1. Kreisl William, MD, et al. “Both Odor Identification and Amyloid Status Predict Memory Decline in Older Adults.” Funded by the National Institute on Aging. 2016; July 26.
2. Lee Seonjoo PhD, et al “Predictive Utility of Entorhinal Cortex Thinning and Odor Identification Test for Transition to Dementia and Cognitive Decline in an Urban Community Population.” Funded by the National Institute on Aging. 2016; July 26.