A new US study reveals that the inability to smell scents, such as peppermint, may be linked to early signs of dementia.
A team of researchers from the University of Chicago carried out a study of nearly 3,000 adults aged 57 to 85, looking at whether a decline in the sense of smell could verify a dementia diagnosis.
Previous research has shown that the twisted fibers of a protein called tangles that are characteristic of Alzheimer’s can be found in the olfactory system of a human body and that dementia is linked to a decrease in this sense.
In the study, people sniffed five different odors: peppermint, fish, orange, rose and leather. These were taken from a larger test used to evaluate sense of smell.
After a five-year follow up, all those who couldn’t physically detect any of the scents had dementia and almost 80 percent of those who could only detect one or two scents also had the disease.
According to the study author, Dr. Jayant Pinto, the findings are important because they show that the central nervous system warns people about potential health dangers.
“The sense of smell is a little bit of an ignored sense,” magazine Newsweek reported Pinto as saying.
According to a neurologist, Ronald Petersen, contemporary dementia research is more focused on determining the risk factors that make people more likely to develop the disease later on, hence an important part of diagnosing patients early comes down to spotting warning signs and testing them.
Dr. Mony de Leon, director of the Center for Brain Health at NYU Langone Health, called the new research “interesting,” but in order to receive a more accurate correlation between dementia and loss of smell, a much larger sample size is required.
Nevertheless, if combined with other tests analyzing factors such as gait and vision, which previously have been researched for their association with dementia, the new finding could be vital.