Loss of sensory discrimination associated with dementia in Parkinson’s disease

The nerves in the nasal passages signal our brains to warn us of what we are sniffing. As we grow older, our sight, hearing, and smell diminish. Loss of the ability to distinguish one odor from another, such as vanilla and cinnamon, can be an early sign of dementia or Parkinson’s disease. Current Asthma and Allergy Report And 2016 research Neurology found.

A cold, flu, or a viral infection such as COVID-19 may cause a temporary loss of smell, but it usually reoccurs. Inadequate odor discrimination in adults (the ability to distinguish one scent from another and the overall ability to smell) is associated with a significant increased risk of later dementia, according to a 2020 study. doing. Frontier of neuroscience..

Early diagnosis

Loss of ability to discriminate odors indicates dysfunction of areas of the brain involved in odor discrimination and naming, said Devangere P. Devanand, a professor of psychiatry and neurology at Columbia University’s Irving Medical Center. I am. However, further research is underway.

“We don’t fully understand how changes in the sense of smell affect a person’s overall risk,” says Devanand. About 4% of the population has been unable to identify odors since childhood, but it has nothing to do with dementia, he adds.

When the patient notices a diminished ability to discriminate odors, Devanand presents the patient with a test containing 12 scratches and snuff samples. You will be asked to identify the aromas of pizza, apples, coffee, petrol, etc. Tests are usually done when a patient or family member notices a slight defect in their memory and odor identification, he says. If someone has a low score on the odor discrimination test and shows memory loss during the test, it triggers further tests to confirm the diagnosis. Patients can wait and follow up later if they score good on the odor discrimination test and are okay with the memory test, or if they are still worried, they can take further tests, He says.

There is no cure for dementia or Parkinson’s disease, but odor identification tests can lead to early diagnosis. Otorhinolaryngologists can look at the tissue of the patient’s nose under a microscope to look for obvious signs of Alzheimer’s disease or another type of dementia, says Philadelphia faculty member Johannes Riser. increase. Monel Center, An independent non-profit scientific laboratory specializing in taste and smell research. “It can lead to an early diagnosis,” he says, because the loss of smell precedes other symptoms.

Heather Snyder, Vice President of Medicine and Science at the Alzheimer’s Association, says early diagnosis is “very important.” It allows people to create their plans for their health care and personal finances. Participation in clinical trials is more feasible in the early stages of the disease, and participation in the trial gives patients access to new treatments that “may be appropriate in the early stages of the disease.”

The behavior of some people with dementia changes, so it is helpful for families to know about the diagnosis, says Devanand. “Families are really angry when they don’t realize this is happening.” He said those who lost their sense of smell should take their concerns seriously and consult a doctor to investigate further. say.

Slow progress?

“There is no established way to delay the onset of dementia. What people can do may have a very small effect,” says Devanand, especially regular exercise, diet. Mediterranean Diet and brain stimulation.

“Exercise and fitness are also important. Does fitness improvement, which has been shown to have a slight impact on cognitive performance, reduce the risk of brain stroke and ministrokes, or reduce the risk of developing Alzheimer’s disease? I don’t know if it’s specific to that, “says Devanando.

Specifically, the guidelines require moderately intensive exercise for at least 30 minutes, at least three days a week, says Carolyn Fredericks, a neurologist at Yale Medicine. Studies showing cognitive benefits were based on exercises that make you breathe hard and stimulate your heart, she says.

Fredericks says that a Mediterranean diet has also been shown to help cognition. She advises patients to eat as if they were on vacation on the Italian coast. Lots of fish, lean protein, beans, protein-containing vegetables, fruits, and dark leafy vegetables appear to have special benefits in maintaining cognitive function. And olive oil and whole grains, not butter, “she says. “It’s not really a restrictive diet, but it’s a diet style that seems really good for the brain.”

Again, Devanando asks if the benefits of this diet reduce the risk of small strokes that occur with age and can affect cognition, or whether the diet directly prevents Alzheimer’s disease. Or say it’s not clear if it will be delayed.

Research on brain games is underway, but everything that people do to move their brains to challenge and increase their brain activity “helps reduce the chances of being diagnosed with the disease,” he said. Says. Learning new skills, keeping your brain moving, and socializing contributes to cognition. Training the brain “accumulates cognitive reserves. You have more intellectual ability to compensate for the memory loss you are facing,” says Devanando. “This is a way to improve resilience when you get sick.”

Drugs approved for the treatment of Alzheimer’s disease have significantly improved cognitive performance, including memory test performance, compared to placebo in clinical trials, Devanando said in a recent announcement in June 2021. The research is quoted and stated. Neuropharmacology.. However, the drugs used to treat Alzheimer’s disease “do not really change the long-term course of the disease,” he says.

The controversial aducanumab US Food and Drug AdministrationHas been shown in two studies to reduce the accumulation of plaque in the brain, but clinical measurements showed a small effect in one study and no effect in the other. Medical practices such as Devanando, Cleveland Clinic and Mount Sinai Health System in New York said they would not prescribe.