Dogs trained to detect Parkinson’s disease using scent have shown remarkable accuracy in new research. The University of Bristol conducted a double-blind trial, where dogs identified skin swabs from people with Parkinson’s with up to 80% sensitivity and 98% specificity, even when other health conditions were present.
The findings offer hope for a simple, non-invasive diagnostic method using biomarkers that appear long before traditional symptoms, potentially allowing earlier treatment and slowed disease progression.
Parkinson’s disease is a progressive neurodegenerative disorder that primarily affects movement, but can also impact mental health, sleep, and pain. It is characterized by symptoms like tremors, slow movement (bradykinesia), and muscle stiffness (rigidity).
For the study, two dogs were trained by the charity, Medical Detection Dogs, to distinguish between sebum swabs from people with and without Parkinson’s disease. The two dogs were Golden Retriever named Bumper and Black Labrador called Peanut.
The dogs were trained over a number of weeks on over 200 odour samples from individuals that had tested positive for Parkinson’s and control samples from people who did not have the disease. Samples were presented to the dogs on a stand system and the dogs were rewarded for correctly indicating a positive sample and for correctly ignoring a negative sample.
The double-blind testing meant that only a computer knew where the correct samples were. In addition, each line was also presented in reverse order so that samples for which no decision was made were re-presented. Then any unsearched samples were collected together in new lines, until a decision had been made for all samples.
A definitive diagnostic test for Parkinson’s Disease remains elusive, so identification of potential biomarkers could help diagnosis and timely intervention.
Claire Guest, Medical Detection Dogs CEO and Chief Scientific Officer, says in a research note: “We are extremely proud to say that once again, dogs can very accurately detect disease.”
Guest adds: “There is currently no early test for Parkinson’s disease and symptoms may start up to 20 years before they become visible and persistent leading to a confirmed diagnosis.
“Timely diagnosis is key as subsequent treatment could slow down the progression of the disease and reduce the intensity of symptoms.”
he dogs in the study achieved high sensitivity and specificity and showed there is an olfactory signature distinct to patients with the disease. Sensitivity levels of 70% and 80% are well above chance and I believe that dogs could help us to develop a quick non-invasive and cost-effective method to identify patients with Parkinson’s disease.
The research appears in Journal of Parkinson’s Disease, titled “Trained dogs can detect the odor of Parkinson’s disease.”
