elderly person smelling

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BALTIMORE — A simple smell test could help doctors screen older adults for signs of frailty and unhealthy aging. Researchers from Johns Hopkins demonstrated that the loss of smell may be predictive of a higher risk for age-related health problems.

So far, studies have shown that smell dysfunction acts as an early indicator of cognitive decline, but these findings expand on this concept and show that the link to frailty is both in the brain and the nose. For this study, researchers assessed olfactory sensitivity and olfactory identification, which describe the ability to detect an odor and the ability to detect and name an odor, respectively.

“We use our sense of smell to identify the threat of a fire or to enjoy the fragrance of flowers on a spring day. But just like vision and hearing, this sense weakens as we age,” says corresponding author Nicholas Rowan, M.D., associate professor of otolaryngology – head and neck surgery, in a university release. “We found that both impaired olfactory identification and sensitivity functions are associated with frailty, which is interesting because it shows that it’s not just your aging brain at work here, but it may also be something peripheral, like something at the level of your nose that is able to predict our impending frailty and death.”

Better smelling skills linked to better overall health

Rowan and the team analyzed data on 1,160 older adults enrolled in the National Social Life, Health and Aging Project between 2015 and 2016. Study participants were exposed to five scents to measure identification skills and six scents to measure sensitivity. The team then matched these results to their frailty score.

They determined that for each one-point increase in both olfactory identification and sensitivity scores, frailty status declined significantly, which suggests that the ability to smell well has a connection to better overall health in the aging population. From this, the team can deduce that keeping an eye on sense of smell may serve as an influential biomarker and risk factor for frailty.

Rowan believes that this work contributes to growing evidence in favor of using smell tests as an integral part to clinical care for aging people that may be cognitively impaired.

“We already do tests to assess how well we can see or hear, and it’s just as easy to conduct a simple smell test that takes only minutes, which could potentially be used as a valuable tool to assess the risk of frailty or unhealthy aging,” says Rowan. “For example, if someone flunks a smell test then maybe this patient needs to improve their nutrition or undergo a more detailed neurological or medical workup.”

The Hopkins team is already looking into the use of smell tests and how they can enhance clinical and research efforts in improving care for older adults, especially with COVID-19 affecting the smell of many patients around the world.

The findings are published in the Journal of Gerontology.

About Shyla Cadogan, RD

Shyla Cadogan is a DMV-Based acute care Registered Dietitian. She holds specialized interests in integrative nutrition and communicating nutrition concepts in a nuanced, approachable way.

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4 Comments

  1. Jerry C Hornbuckle says:

    There may be a special circumstance you have overlooked, maybe two. At age 5 we lived in out in the country in a sparsely populated area. In order to play baseball, everyone from age 5 to 18 had to participate. But at age 5 I could not throw the ball far enough to play any defensive position except “pitcher”. On one occasion, a 16 year old batter, who was large for his age, hit a line drive that hit my nose squarely. It splattered blood over 6 feet and knocked me unconscious. Everyone fled because they thought I had been killed, but someone told my father who carried me to the Emergency Room. As a result, most of “olfactory sensor” was severely damaged and left me with almost no ability to smell anything … from age 5 to my now age of 80 years. However, I do have now a declining sense of taste.

    I believe there may be others like me that are exceptions to the author’s assertions relating reduced sense of smell to declining health. There may be another one I have, too.

    As a subject in a VA study related to brain function, it was discovered that I have an inherent condition called “pre-cortal processing”. All of our senses are fed into the brain via nerves that pass through ganglia that modifies the signals in the same sense as electronic signal processing. But in my case, they discovered I was “thinking” and making decisions in those ganglia before the information ever reached my brain. Please note this applies to all senses except for “smell”, which is not subject to a ganglia performing signal processing.

    I believe both perhaps ought to be considered in this research.

  2. SuzanneL says:

    “For example, if someone flunks a smell test then maybe this patient needs to improve their nutrition or …”

    There’s no “or”. This sentence fragment is the heart of the article. Go on, say it. Loss of sense of smell primarily indicates zinc deficiency. Covid uses up your body’s stores of zinc fighting the virus, which is why “covid causes loss of smell”. Hydroxychloroquine helps the body absorbe dietary zinc, hence it had to be banned. But not to worry, the natural original, quercetin, also found in many foods such as garlic, also helps you absorb zinc. So they’ve already come for our primary sources of zinc – meat and eggs. Next they will come for our other main source of zinc – beans. You watch.

    1. walker roamer says:

      Totally agree with you. Got Covid in early 2020. Was given HCQ before the ban and walked out of the hospital. Probably they will blame beans on Sudden Adult Death Syndrome…

    2. Bubba Six Pack says:

      Haha, coming for our beans.