Breakthrough smell test may help early detection of Alzheimer’s

Breakthrough smell test may help early detection of Alzheimer’s

Alzheimer’s disease, a degenerative condition that badly affects memory and other crucial brain functions, is the sixth leading cause of death in the United States. Almost 44 million people suffer from it worldwide, of which 5.4 million are Americans.

The symptoms of Alzheimer’s surface slowly and gradually exacerbate, disrupting the everyday functioning of the patient. Early diagnosis of Alzheimer’s has so far been difficult. However, two recent studies suggest that an odor test may be instrumental in diagnosing early-stage Alzheimer’s disease.

The two separate studies, carried out by researchers from Columbia University Medical Center (CUMC), New York State Psychiatric Institute, and New York-Presbyterian, were presented at the 2016 Alzheimer’s Association International Conference (AAIC). They indicated possible predictors of cognitive impairment and early-stage Alzheimer’s disease that may help health care providers in early detection and intervention of the disorder.

The current methods of diagnosing Alzheimer’s can only detect the disease in the later stages of its development and are quite expensive. However, the two studies suggest that the University of Pennsylvania Smell Identification Test (UPSIT), which is the gold standard of smell identification tests in diagnosing disorders like Parkinson’s disease and Alzheimer’s, can be a cost-effective alternative to the currently available detection tests.

Lower odor detection test score means higher risk of Alzheimer’s

During one of the studies, researchers from CUMC gave UPSIT to 397 dementia-free people whose average age was 80 years and observed them for four years. They took brain scans of all the respondents to measure the thickness of the entorhinal cortex, the first region of the brain affected by Alzheimer’s disease.

After the four-year period, the researchers noticed that out of the 397 respondents 50 (12.6 percent) developed Alzheimer’s disease, and one in five of the participants (nearly 20 percent) showed signs of cognitive decline. They also observed that lower scores in the smell identification test, not measure of the entorhinal cortex, was closely related to dementia and Alzheimer’s disease.

Low UPSIT scores predict a decline in the ability to identify odors accurately. Thinning or thickening of the entorhinal cortex was associated with a low score in those people who developed dementia or Alzheimer’s.

“Our research showed that odor identification impairment and, to a lesser degree, entorhinal cortical thickness were predictors of the transition to dementia,” said Seonjoo Lee, Ph.D., presenting author at the conference, and assistant professor of clinical biostatistics (in psychiatry) at CUMC.

The findings also corroborate odor identification as an early predictor and indicate that impairment in odor identification may be a precursor to thinning in the entorhinal cortex in the early stage of Alzheimer’s disease, Lee added.

UPSIT score and amyloid status predict memory decline

In the second study, the researchers examined smell scores of 84 (median age 71 years) elderly people (through UPSIT) in combination with either beta amyloid positron emission tomography (PET) scanning or a spinal tap to analyze the cerebrospinal fluid. PET scans reveal plaque (beta-amyloid plaques) in the brain, while spinal taps reveal plaque in cerebrospinal fluid.

After six months of observation, the researchers noticed that out of 84 participants, 58 suffered mild cognitive impairment. The study concluded that PET scanning and cerebrospinal fluid could more accurately predict memory decline, but the smell identification test could not. However, older adults with a UPSIT score less than 35 were thrice as likely to suffer memory decline, as compared to those with a score greater than 35.

“Our research suggests that both UPSIT score and amyloid status predict memory decline,” said Dr. William Kreisl, assistant professor of neurology at CUMC and neurologist at New York-Presbyterian/Columbia.

Road to recovery

Inability to remember important moments, feelings, people, and places that make up one’s past can be frustrating, particularly during the old age. Seclusion further brings boredom and depression, making older people vulnerable to various physical and mental illnesses. However, there are ways to keep them engaged and make them feel loved.

If you or your loved one is suffering from any mental condition that is affecting his day-to-day life, it is imperative to seek immediate help. For more information about mental health treatment centers in Colorado, you may contact the Colorado Mental Health Helpline. Call our 24/7 helpline number 866-899-5063 or chat online with one of our experts to know more about mental health centers in the U.S.