Researchers from the Technical University of Dresden (Germany), the Monell Chemical Senses Center (USA), the University of East Anglia, University College London, and the charity SmellTaste (UK) say a diminished sense of smell is often linked to a range of diseases.
Worldwide, olfactory disorders affect one in five people. The majority of those affected are men over 60. Recent studies have also shown that smell loss occurs eight to ten times more frequently in people who have had COVID-19.
In a review published in Clinical Otolaryngology, the team says the global medical community often overlooks olfactory disorders.
This is despite recent findings linking a weakened sense of smell to more than 130 neurological, physical, and genetic disorders, and despite the condition being more common than profound hearing loss.
The authors say the primary cause of a diminished sense of smell is chronic rhinosinusitis — inflammation of the nasal sinuses that can be triggered by airway-blocking diseases such as asthma or cystic fibrosis, according to the Daily Mail.
They pointed out that there is growing evidence that loss of smell can be an early sign of several diseases, including dementia and, more concerningly, life-threatening heart problems.
The researchers explain that harmful proteins in people with dementia may begin to accumulate in the part of the brain responsible for smell.
The review says loss of smell can occur before traditional motor symptoms in 90 percent of patients with Parkinson’s disease, sometimes up to five years before diagnosis.
There is also growing evidence that loss of smell is associated with an increased risk of stroke and heart failure in previously healthy adults.
The team noted that many people with a diminished sense of smell worry about their safety because they can’t detect gas leaks, fire, smoke, or spoiled food.
The team pointed to recent studies that found loss of smell is linked to more frequent eating disorders, social isolation, relationship difficulties, anxiety, and depression. They added that patients with impaired smell tend to have a less varied diet, consuming more fats and sugars.
“We recommend developing educational programs in the field of smell health and awareness campaigns, implementing smell screening, and creating and enforcing smell health policies,” the researchers wrote in their review.
Photo: Unsplash, Openverse
