As if we didn’t need another reason to worry about losing our sense of smell these days, a new study has found that a rapid decline in the ability to smell could be a sign of dementia.
The study from University of Chicago Medicine, which examined 515 older adults, was based on the premise that the distinctive plaques and tangles found in brain tissue affected by Alzheimer’s Disease tend to occur in regions responsible for memory and olfactory ability (that’s sense of smell) first, though it’s unknown if that damage actually causes the loss of smell.
“Our idea was that people with a rapidly declining sense of smell over time would be in worse shape – and more likely to have brain problems and even Alzheimer’s itself – than people who were slowly declining or maintaining a normal sense of smell,” said study lead Rachel Pacyna, a rising fourth-year medical student at the University of Chicago Pritzker School of Medicine.
The researchers discovered that a person quickly lost their ability to smell during a period of normal cognition predicted several hallmarks of Alzheimer’s, including less grey matter in areas of the brain relating to smell and memory, worse cognition, and higher dementia risk, according to senior author Jayant M. Pinto, MD.
“We were able to show that the volume and shape of grey matter in olfactory and memory-associated areas of the brains of people with rapid decline in their sense of smell were smaller compared to people who had less severe olfactory decline,” he said.
This research could lead to the use of smell tests – similar to sight and hearing tests – in clinics to try and give patients advance warning of dementia, Ms Pacyna said.
“If we could identify people in their 40s, 50s and 60s who are at higher risk early on, we could potentially have enough information to enrol them into clinical trials and develop better medications.”
So keep an eye on your nose, and be ready to act at the first whiff of trouble.
