Dogs can alert their owners to impending epileptic seizures, according to research led by Queen’s University Belfast, which shows that “man’s best friend” could also save lives.
All 19 dogs in the study reacted to the smell associated with a seizure by making eye contact with their owners, touching them, crying or barking, the researchers found.
None of the dogs had previous training for this task, but scientists believe if they can train dogs the discovery has the potential to help people with epilepsy predict the onset of seizures and thereby greatly improve their safety.
About one in five people with epilepsy are unable to control their seizures with medication. At present there is no reliable early-warning device to predict the onset of seizures, leaving sufferers at risk of serious injury and death, as well as social stigmatisation.
There have been anecdotal accounts of pet dogs predicting seizures by demanding attention, but the researchers say to date no scientific study has investigated the truth of these claims.
"We hypothesised that, given the extraordinary sense of smell of dogs, a volatile organic compound exhaled by the dog's owner may provide an early warning trigger mechanism to make dogs react before the seizure," said lead researcher Dr Neil Powell, from Queen's school of biological sciences.
He said the results show that pet dogs are “a reliable source” for detecting the onset of seizures.
Reactions
Researchers used a specially-designed apparatus – a remote odour delivery mechanism – to deliver seizure-associated odours as well as other odours and to record the reactions of the dogs to each.
Using sweat harvested from people with epilepsy the researchers exposed the dogs to odours captured before, during and after seizures.
They found all 19 dogs demonstrated “more affiliative behavioural changes” when confronted by seizure-associated odours compared with their response to control odours.
The research, published in MDPI Animals, was funded by Epilepsy Ireland and Disability Assistance Dogs.
"A reliable method of seizure prediction and detection is the holy grail for many people living with epilepsy, as well as the parents of children with the condition," said Peter Murphy, chief executive of Epilepsy Ireland.
“While recent efforts have focused on technological solutions it is exciting and very welcome news that anecdotal reports of dogs’ ability to predict seizures have now been backed up by scientific evidence.”