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Loss Of Smell Linked To Increased Dementia Risk, Study Warns

People with Alzheimer's gene have poorer sense of smell, indicating early signs of cognitive decline.

Losing the sense of smell could be an early sign of dementia, warns a new study.

Researchers found that people with one Alzheimer’s gene were 37 percent less likely to have a good sense of smell.

Those who carry the APOE e4 gene, known to increase the risk of degenerative memory loss disease, started to lose their ability to scent at 65 to 69 years old.

On a zero to six scale measuring how many odors they could sniff, gene carriers by that age could detect an average of 3.2 smells versus 3.9 smells for those who had no such gene.

By the time they were 75 to 79 years old, gene carriers started to struggle to identify what they were smelling.

Once that became shaky their ability to smell declined at a faster pace than non-carriers.

Thinking and memory skills were among the same between the gene carriers and those without, but the former experiences a faster decline in their thinking skills over time than their counterparts, as was expected by the researchers.

A doctor holding an MRI result of the brain. Researchers found that people with one Alzheimer’s gene were 37 percent less likely to have a good sense of smell. ANNA SHVETS VIA PEXELS.

“Testing a person’s ability to detect odors may be a useful way to predict future problems with cognition,” said Dr. Matthew Goodsmith of the University of Chicago.

The doctor went on to say, “While more research is needed to confirm these findings and determine what level of smell loss would predict future risk, these results could be promising, especially in studies aiming to identify people at risk for dementia early in the disease.”

“Identifying the mechanisms underlying these relationships will help us understand the role of smell in neurodegeneration,” said Dr. Goodsmith.

His team tested how well participants could pick up an odor, and their ability to identify what they were smelling.

Alongside that, DNA samples provided insight into who carried the gene linked with an increased risk of Alzheimer’s.

Every five years, the experts sent a survey to 865 participants to complete at home, measuring their ability to detect an odor and whether they could clock what they were smelling.

Each test produced a grade between zero and six grade.

The participants’ thinking and memory skills were also tested twice, five years apart, for the study published in the journal Neurology.

Produced in association with SWNS Talker

Edited by Priscilla Jepchumba and Judy J. Rotich

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