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SUNDAY, Feb. 3 (HealthDay News) -- Irish researchers hope to prove that a dog's keen sense of smell gives it the ability to watch over the blood sugar levels of diabetics.
Canines have already shown themselves capable of leading the blind, alerting the deaf, and helping the physically disabled with daily tasks.
But researchers at Queen's University in Belfast, Northern Ireland, are taking the "helpful companion" idea one step further by gathering scientific evidence that could verify dogs can reliably detect dangerous blood sugar level drops in diabetics.
"Anecdotal reports suggest that some dogs can perform early warning of hypoglycemia by using their sense of smell to 'sniff out' if their owner's blood sugar levels are dropping," said lead researcher and psychology professor Deborah Wells.
More than 20 million U.S. children and adults have diabetes, according to the American Diabetes Association. Those with the disease do not produce enough insulin, a hormone the body needs to convert sugars, starches and other food into energy.
Diabetics must test their blood glucose level regularly, even sometimes in the middle of the night to avoid the peaks and valleys that can cause organ failure, say experts.
Wells hopes to find out what cues dogs pick up on so they can officially be recognized and trained as early-warning systems for diabetics.
At least two organizations in the United States already train dogs to detect low glucose levels. But exactly what the canines notice when a person experiences a blood sugar low is still a mystery, said Mark Ruefenacht, founder of Dogs for Diabetics, in Concord, Calif.
The organization is working with a forensic laboratory to identify a possible odor.
"We just haven't come up with the right answers," he said. "Every time we think we have the answer, we find that we don't."
Ruefenacht, a diabetic, started the organization three years ago, inspired after a puppy he was raising for Guide Dogs for the Blind woke him one night. Ruefenacht forgot to check his blood sugar before going to sleep, and he thinks he had a seizure that alarmed the pup.
Since then, the all-volunteer group has placed 30 trained canines in the homes of Northern California residents with type 1 diabetes.
Demand for the dogs is high; more than 100 people are on the waiting list.
Dogs for Diabetics uses Labrador retrievers that don't graduate from guide dog school. These dogs usually flunk for reasons such as refusing to walk in the rain or step onto an escalator -- all skills important for being a working dog, but not a general assistance one.
Ruefenacht said his dogs undergo three to four months of training similar to what is used to prepare dog to detect narcotics or explosives. The 2-year-old canines are first taught to detect scent samples of low blood sugar. Then they learn to find that scent on people, and alert others by holding in their mouth a soft tube that hangs from around their neck.
Dogs that successfully complete training are 90 percent accurate, Ruefenacht said.
These clever canines aren't the only ones that must learn new tricks.
Mary Simon has battled diabetes for more than three decades, and she now drives four hours each week from her home in Fresno to attend the required class.
"I need this dog desperately," said Simon, a diabetic who is also medical director for the Diabetic Youth Foundation in Concord, Calif.
Medication she takes hampers her ability to feel nighttime lows, she said, and the special glucose sensor she wears doesn't always work.
When Simon first learned of the hypoglycemic detection dogs a few years ago, she didn't think their talent was needed because glucose sensors were about to hit the market. Since then, she's changed her mind.
"My own personal experience is we need [the dogs] right now," she said.
Not everyone is so quick to put their trust in the canines' ability.
Larry Myers, a veterinarian and professor at Auburn University in Alabama, has trained dogs to detect everything from drugs to agricultural pests for 25 years. He said the jury is still out on whether dogs can truly detect low blood sugar levels, but he believes it's a possibility worth exploring.
Even though dogs have amazing olfactory abilities, he said they are not universally sensitive to all chemicals.
"Do hypoglycemic individuals, in fact, emit an odor that is characteristic? I don't know, and I don't think anybody does know right now," he said.
A possibility other than scent is the dogs are picking up on visual cues, which is thought to be the case with seizure detection dogs. Such dogs allegedly can pick up on extremely subtle physiological changes in their human companion that may begin five to 45 minutes before an actual attack. The dogs then warn the humans so they can find a safe environment or take precautionary measures.
"It turns out what the dogs are really sensitive to is subtle changes in behavior of the individuals just prior to seizing," Myers said. "It's more of a fact that dogs are very, very, very observant of human behavior."