A decreased sense of smell could be a sign of declining health and potential frailty, a new study has warned.
Doctors from Johns Hopkins University in the United States compared the olfactory abilities of more than 1,000 elderly people with a questionnaire and an assessment of their health which produced a frailty score.
They found that those who were the most frail and had the worst overall physical health standards also had the worst sense of smell.
The finding suggests that smell loss could be a useful indicator of the overall health of older people and the team called for it to be included in future health checkups.
Adding smell tests to routine screenings could help identify a person’s risk of unhealthy aging and indicate whether further testing is needed, they argue.
“We already do tests to assess our ability to see or hear, and it’s just as easy to perform a simple smell test that only takes a few minutes, which could potentially be used as a valuable tool to assess frailty risk. or unhealthy aging,” said Dr. Nicholas Rowan, associate professor of head and neck surgery at Johns Hopkins University and author of the study.
“For example, if someone misses a smell test, then maybe that patient needs to improve their nutrition or have a more detailed neurological or medical workup.”
The study builds on previous research that shows a decline in the ability to smell is a common early sign of cognitive decline.
However, the results suggest that the link to frailty is probably not just in the brain, but also a real decline in olfactory ability.
The study, published in the Journal of Gerontology, tested participants’ abilities to detect the presence of an odor and name a scent.
These measurements are called olfactory sensitivity and olfactory identification, respectively.
Olfactory identification relies on the brain to help determine what smell is and suggests that neurological function may help explain the relationship between smell and frailty.
Dr Rowan said: “We use our sense of smell to identify the threat of fire or to appreciate the scent of flowers on a spring day. But just like vision and hearing, this sense weakens with age. .
“We found that impaired olfactory identification and sensitivity functions are associated with frailty, which is interesting because it shows that it’s not just your aging brain working here, but it could also be something device, like something in your nose that is able to predict our impending frailty and death.”
However, it remains to be seen exactly how worsening odor relates to deteriorating health.
Common consequences of loss of smell include loss of appetite, difficulty monitoring personal hygiene, depression, and an inability to detect toxic fumes.
For older people, it can also lead to weight loss, malnutrition, weakness, inadequate self-care, and even potential injury from gas leaks or fires.
Frailty is a key marker of old age and health decline and can be delayed by exercise, good habits and a healthy diet.
Loss of the senses is a common indicator of poor health, with hearing loss, for example, linked to Alzheimer’s disease.
Dr Sarah Bauermeister, a senior scientist at Dementia Platforms UK and an academic at the University of Oxford, calls on people to get regular hearing checks throughout their lives to detect any hearing decline that could be a warning sign- runner of a future Alzheimer’s disease.
Hearing loss, she says, is the most important factor that can increase a person’s risk of degenerative disease.
“Regular hearing checks are very important, and this throughout life, so having a hearing check is normal whether you are in your 30s or 40s,” she said.
“If we normalize hearing checks, that will normalize wearing a hearing aid and then the stigma will be reduced.”