According to a new study, having a decreased sense of smell may be a telltale sign of early dementia. This discovery was published in JAMA Neurology. In a previous study, olfactory loss was also linked with cognitive decline, vascular dementia, and Lewy body.
Researchers posited that olfactory impairment may be used a crucial marker to predict the onset of Alzheimer's disease.
Led by Rosebud Roberts of the Mayo Clinic, the researchers examined the olfactory capabilities of 1,430 cognitively normal people; the average age of the participants is 79.5 years old. Throughout the research period, those who experienced decline in their sense of smell had a corresponding decrease in cognitive functioning.
The participants were tested on their sense of smell, which involved 6 food-related and 6 non-food-related items. The items included turpentine, cinnamon, paint thinner, chocolate, and gasoline. All they had to do was scratch, sniff, and identify these items.
After scoring the participants based on the correct answers in the smell test, those who experienced difficulty identifying the scents showed an increased risk for mild cognitive impairment.
Those with mild cognitive impairment are likely to encounter memory disorders more serious than normal. However, such diminishing mental faculty is not serious as to cause problems in day-to-day life. Cognitive impairment may include impaired analytical, organizing, or judgment skills.
“Clinical implications of our findings are that odor identification tests may have use for early detection of persons at risk of cognitive outcomes,” the researchers posited.