Dampening of the Senses Is Linked to Dementia Risk

A decline in smell was the sense loss most strongly associated with such risk in a recent study. Christopher Intagliata reports.

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Memory loss and forgetfulness are common warning signs for dementia. But a dulling of the senses also appears to be associated with dementia. 

“Smell is definitely the strongest one we found, but it does seem like it’s not just smell.”

Willa Brenowitz, an epidemiologist at the University of California, San Francisco. Her team studied cognitive decline in 1,800 adults from the Health, Aging and Body Composition Study—which tracked the health and mental function of older adults over a 17-year period.


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During the study, the subjects completed sensory tests—including hearing, smell, touch and vision. Brenowitz’s team then compared the adults’ overall sensory abilities to their mental function. The results? 

“Those with better function had a lower risk of dementia. And with worse sensory function, they had higher risk of dementia.”

A decline in smell, in particular, had the strongest link to dementia. The results are in the Journal of the Alzheimer’s Association: Alzheimer’s & Dementia. [Willa D. Brenowitz et al., Incident dementia and faster rates of cognitive decline are associated with worse multisensory function summary scores]

The scientists were just studying correlations here. But Brenowitz says if they can figure out how well multisensory decline predicts dementia risk, it might give doctors another tool to screen for the disease.

—Christopher Intagliata

[The above text is a transcript of this podcast.]

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