It may be possible to detect the early stages of Alzheimer’s disease through urine odor, potentially leading to a non-invasive test for the most common form of dementia.

In a study published Thursday in Scientific Reports, researchers used an animal model to focus on changes to body odor caused by factors that originate outside the body, such as viruses and vaccines.

"Now we have evidence that urinary odor signatures can be altered by changes in the brain characteristic of Alzheimer's disease,” study author Dr. Bruce Kimball, a chemical ecologist with the USDA National Wildlife Research Center (NWRC), said in a news release. “This finding may also have implications for other neurologic diseases."

Using three different types of mice genetically altered to mimic the brain and behavioral changes seen in Alzheimer’s disease, researchers found that each strain of mice produced urinary odor profiles that were distinct from those of the control mice. These differences were due to differences in concentrations of the same compounds, Medical News Today reported.

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According to researchers, the differences in odor signature preceded the detectable amounts of amyloid plaque build-up in the brains of the test mice, suggesting the odor is tied to the underlying gene, rather than progress of changes in the brain.

Alzheimer’s disease, a type of dementia that affects memory, thinking and behavior, affects an estimated 5.3 million Americans, according to the Alzheimer’s Association.