Hit your head, lose your sense of smell

It has long been known that people who experience a great concussion can temporarily lose their sense of smell and develop emotional problems such as anxiety and depression. Scientists have now found that this is true even for people who experience a minor concussion.

Falling off the bike with a helmet, having a windshield in the car, hitting the ski slopes, sliding on the ice and banging your head – such minor accidents can cause the same problems of olfaction and olfaction. anxiety, the researchers found.

In a study published in Cerebral lesion – brain-damageAn international team led by neuropsychologists from the Université de Montréal compared 20 patients hospitalized with mild concussion to 22 patients who had a fracture to a limb but suffered no concussion. In the 24 hours following their accident, just over half of those with a mild concussion had a reduced sense of smell, compared to only 5 percent of patients with fractures. A year later, although their sense of smell returned to normal, the first group of patients was significantly more anxious than the control group.

"Many people will suffer from a mild concussion at some point in their lives." Realizing the fact that they have trouble feeling is the first step to telling their doctor, "said the doctor. Principal author Fanny Lecuyer Giguère, who did the research as part of her work. PhD thesis in neuropsychology under the direction of Johannes Frasnelli, badociate professor of psychology at UdeM. "It is important for patients to report any loss of smell, as this is not something that their general practitioner or emergency doctor normally asks for."

Identifying the problem is a short step to get personalized treatment, she added, with closer monitoring to see if the loss of smell and anxiety persist, indicating the severity of the injury . Doctors also need to educate their patients so that they will check for symptoms in the weeks following their accident, she said. "This is an awareness issue: the more people are told to monitor the signs of olfactory loss and anxiety, the easier it will be for doctors to respond."

To check his ability to identify odors, Lecuyer Giguère visited hospitalized patients in the alpine ski resort of Visp, Switzerland, between December 2016 and February 2017. Almost all those who suffered a slight concussion had a ski accident. They were all seen within 24 hours of their accident, as were those who had suffered a fracture without a concussion. With their sense of smell "Sniffin 'Sticks" (markers), they were asked to identify the synthetic odors of roses, garlic, clove and solvent, and more.

One year later, patients received a follow-up questionnaire and a series of scratchbooks. By comparing the results of the two groups of patients the day after their injury and 12 months later, the researchers were able to determine that most of the people who had lost their sense of smell had recovered their sense of smell within six months of their accident.

However, their anxiety symptoms did not decrease significantly: thoughts that worried them, difficulties in relaxing and sudden feelings of panic. About 65% of patients with concussion reported such symptoms.

The authors concluded that future studies should focus on a larger sample of patients to better examine the relationship between anxiety and nausea.