Simple Breath Test May Aid in Early Diagnosis of Parkinson’s, Study Reports
A new device that uses just a breath sample might, in the future, help diagnose early-stage Parkinson’s patients or identify those who may be at risk, according to researchers.
The innovative technology, developed by researchers at the Israel Institute of Technology, was able to detect alterations in the breath of newly diagnosed Parkinson’s patients, even before they begin medication.
Although the device and collection method still needs to be perfected to reach the sensitivity of other diagnostic approaches such as brain ultrasound scans, researchers believe the tool shows promise.
Findings were reported in the study, “Sensor Array for Detection of Early Stage Parkinson’s Disease before Medication,“ published in the journal ACS Chemical Neuroscience.
The team had already tested its device in the past, and were able to detect differences in the exhaled breath of people already being treated for Parkinson’s disease and healthy controls.
Now they wanted to see if the device could detect differences in the breath of patients with early-stage Parkinson’s who were not yet on any medications.
The device consists of an array of 40 cross-reactive sensors based on gold nanoparticles or single-walled carbon nanotubes, attached to different chemical ligands. Each of these ligands can bind certain airy or volatile molecules in the breath that change the electrical signals of the sensor.
They tested the device on 29 patients who had recently been diagnosed with idiopathic Parkinson’s disease — with no known cause — and were not yet on medication, and 19 healthy individuals of similar ages, used as controls.
The device’s performance was also compared with other currently used diagnosed tests, namely brain ultrasonography and smell detection.
The sensor was able to distinguish Parkinson’s patients from controls with a sensitivity of 79%, a specificity of 84%, and accuracy of 81%, better than smell detection tests, which have 62% sensitivity, 89% specificity and 73% accuracy, and almost as good as brain ultrasound scans, at 93% sensitivity, 90% specificity, and 92% accuracy.
“[O]ur studies provide additional confirmation of the ability of our sensors array to detect altered breath VOC [volatile organic compounds] composition characteristic of PD [Parkinson’s disease],” the researchers wrote.
Early diagnosis of Parkinson’s can help patients begin neuroprotective therapies sooner, before extensive loss of dopamine-producing nerve cells — those affected in Parkinson’s disease — has occurred in the brain. However, to date, diagnosis is still subject to considerable errors.
So far, studies on early Parkinson’s diagnosis using volatile biomarkers have only been done in patients who are already being treated and medicated. “There is a great need to evaluate untreated patients for establishing a real world screening and diagnostic technology,” the authors said.
Further improvements, as well as more testing in patients, are still necessary for the device to reach the sensitivity of other diagnostic methods like brain ultrasound scans.
“Future development of the sensors array technique has the potential to produce a small, portable system with the advantage of unbiased determination which could be used in initial screening of at-risk subjects without the need for experienced clinical personnel,” the researchers concluded.