According to this study, a simple urine test can detect whether someone has early-stage Alzheimer’s disease, paving the way for large-scale screening programs. Researchers tested a large group of Alzheimer’s disease patients and healthy controls with normal cognitive ability to determine differences in urinary biomarkers.
They found that urinary formic acid is a sensitive marker of subjective cognitive decline that can indicate very early stages of Alzheimer’s disease. Current methods for diagnosing Alzheimer’s disease are expensive, inconvenient, and unsuitable for routine screening. This means that most patients are only diagnosed when it is too late for effective treatment. However, a non-invasive, inexpensive and convenient urine test for formic acid may be just what the doctor ordered for early screening.
Alzheimer’s disease is a persistent and insidious chronic disease, which means that it can develop and persist for many years before overt cognitive impairment appears. The cause of Alzheimer’s disease is still largely unknown. The early stages of the disease occur before the stage of irreversible dementia, and this is the golden window for intervention and treatment. Therefore, large-scale screening for early-stage Alzheimer’s disease is needed for the elderly.
The problem with current diagnostic methods is that they involve positron emission tomography brain scans, which are expensive and expose the patient to radiation. There are also biomarker tests that can detect Alzheimer’s disease, but these require invasive blood or lumbar puncture to obtain cerebrospinal fluid, which can be terrifying for patients.
However, urine testing is noninvasive and convenient and would be well suited for large-scale screening. Although researchers have previously identified urinary biomarkers for Alzheimer’s disease, none have been able to detect early stages of the disease, meaning the window for early treatment remains elusive.
Formic acid may be the key to early diagnosis of Alzheimer’s disease
The researchers behind this new study previously investigated an organic compound called formaldehyde as a urinary biomarker for Alzheimer’s disease. However, there was room for improvement in early stage disease detection. In this latest study, they focused primarily on formic acid, a metabolic product of formaldehyde, to see if it would perform better as a biomarker.
A total of 574 people participated in the study, and the participants were either healthy volunteers with normal cognitive abilities or had disease progression ranging from subjective cognitive impairment to full-fledged disease. The researchers analyzed the participants’ urine and blood samples and conducted psychological assessments.
Urinary formic acid levels were found to be significantly increased in all Alzheimer’s groups compared to healthy controls, including the early-stage subjective cognitive decline group, and were associated with cognitive decline. This suggests that formic acid may act as a sensitive biomarker for early-stage Alzheimer’s disease.
Interestingly, when the researchers analyzed urine formic acid levels along with blood-based Alzheimer’s biomarkers, they found that they were able to more accurately predict what stage of the disease a patient was at. However, further research is needed to understand the link between Alzheimer’s and formic acid.
The researchers concluded that urinary formic acid showed excellent sensitivity for early detection of Alzheimer’s disease. Detection of urinary biomarkers of Alzheimer’s disease is convenient and cost-effective and should be performed during routine physical examinations of the elderly.
- Systematic evaluation of urinary formic acid as a new potential biomarker for Alzheimer’s disease – (https:www.frontiersin.org/articles/10.3389/fnagi.2022.1046066/full)