A dog may be man's best friend. But for 2 million Americans with epilepsy, that canine companion could also be a lifesaver.
That's what a new study suggests, after documenting incidents in which the pets anticipated children's epileptic fits up to five hours before the seizure occurs. The research, published this week in the journal Neurology, found dogs demonstrated protective behaviors such as face licking, whining to alert others, and moving a child away from harm when suffering seizures near stair landings or furniture.
No research has yet been able determine exactly how dogs anticipate a seizure, and Dr. Adam Kirton, an author of the findings, stresses the "preliminary" aspect of the study.
But the research, conducted at Alberta Children's Hospital at the University of Calgary, Canada, sought to find anecdotal evidence to support the canine claim, and it appears it did. The research, for instance, found 42 percent of the 48 families with an untrained dog noticed their pets anticipating and reacting to their child's seizures from two minutes to five hours before the seizure occurred.
A similar study was conducted with adults in 2002 by Deborah Dalziel of the Department of Neuroscience at the University of Florida's College of Medicine in Gainesville.
While she is unable to account for the dogs' knowledge, she notes: "Dogs primarily communicate with behavior and facial expressions, so they are more aware than most people. It's certainly possible that they would hear [the seizure], see it, or even smell it."
About one in 100 people have epilepsy, a brain disorder which sometimes disrupts the passage of information through the brain and changes its chemistry, which might be what the dogs are perceiving. Also, most people with the disorder will manifest some physical change before their seizure and pets might notice that.
Finally, as Dalziel explains: "There is some evidence to suggest that our body odors change before we have a seizure. … An in-tune dog will be aware of that and make the connection between those events and a seizure."
A dog's sense of smell is more than 300 times a human's, which may account for the innate difference.
The Truth about Cats and Dogs
Karie Harrison, of Ypsilanti, Mich., began to notice her 4-year-old Pembroke Welsh Corgi "Owen" would respond to her seizures when he was just a year-old: "I started to notice that he would detect it at times, sometimes even before I can."
Harrison hadn't purchased her pet with the idea of needing an aide, but she explains Owen seems to have a natural inclination to respond to her seizures.
Owen would often slightly change his behavior before Harrison noticed a warning signal of a seizure: "A lot of times, we'll be walking, and he'll just stop and sit there, and then I'll realize that I'm having a warning sign," she recounts. "So I'll sit down and Owen will just sit there, laying right by me, protecting me as I have my seizure, and often licking my face."
Neurologists whose patients have experienced seizure-alerts with their pets report similar incidents. Dr. Basim Uthman, a neurologist at the Department of Neuroscience at the University of Florida's College of Medicine in Gainesville, explains: "The natural inclination is to protect the patient. If the person falls during the seizure, they could hurt themselves, so the dogs learn to protect the patient from falling."
But many doctors are still uncertain about the "seizure-alert" responses of pet dogs.
"There is no compelling evidence that dogs do anticipate and respond to seizures, only anecdotal evidence," notes Dr. Nathan Fountain, director of the Comprehensive Epilepsy Program at the University of Virginia in Charlottesville. "The important thing is to note that dogs provide a benefit beyond just anticipating or responding to seizures. It's about quality of life."
Harrison is quick to agree: "Mostly, [Owen] just makes me feel comfortable. When you're coming out of a seizure, you're very disoriented. The fact that Owen is there to comfort me is very important."
Seizure-alert dogs are specifically trained to recognize and respond to their owners' seizures. And while the study noted Owen's breed is not listed among them, Jennifer Arnold, the executive director of Canine Assistants, an Atlanta assisted dog-training program, says, "probably all dogs have the ability to predict seizures. But the dogs who feel the closest bond will want to let people know that this is coming."
In addition, Uthman believes "it is very likely that cats can do this as well." No study has yet examined the relationship between cats and seizure alert or response.
Barking vs. Biting
Despite the positive effects of most reported incidents in the surveys, an equal number of doctors stress the potential danger involving untrained dogs and people with epilepsy, particularly children.
"A seizure can be a very disturbing thing," Dalziel warns. "Dogs and people can respond in various different ways — they can be scared or they can have a good response, maybe guarding the person having the seizure. But a dog, you can't calm them down, and you don't know how they'll respond."
Even protective behaviors leave possible problems. Detroit-based Dr. Gregory Barkley, chair of the Epilepsy Foundation Professional Advisory Board, stresses: "A dog who stands guard and doesn't let a person get robbed during a seizure — which has actually happened to some of my patients — is good, but … how does a dog know between a robber and an EMT [emergency medical technician]?"
Arnold warns her clients of the dangers of untrained dogs in the home: "Certain breeds of dogs, or even specific dogs, respond in inappropriate or potentially dangerous ways … the problem is that we just don't know how they'll respond until there is a seizure."
Many epilepsy specialists and veterinarians around the country remain skeptical, suggesting while there is probably little harm in someone with epilepsy having a household dog, there was not enough evidence to purchase a trained alert or response dog, a cost that can run several thousand dollars.
And the University of Calgary's Kirton stresses, "People and families living with epilepsy should not be buying dogs in the hopes that they will assist them with their seizures."