The 9-year-old Australian Terrier was drinking a lot of water and urinating frequently. So his owner took the little dog to her veterinarian, John Hamil of Canyon Animal Hospital in Laguna Beach, Calif. A urinalysis and blood work revealed that he had diabetes.
As with people, the incidence of diabetes in cats and dogs is increasing. Not so much of a problem in decades past, diabetes now affects as many as one in 50 of the animals, some statistics show, especially pudgy pets.
“There is no question from what I know that is published in the literature that obesity is on the rise, No. 1, and No. 2, diabetes is on the rise right along with it,” says veterinarian Robin Downing, hospital director of Windsor Veterinary Clinic in Windsor, Colo.
Diabetes results when the body doesn't produce enough insulin, a hormone that processes glucose (blood sugar), or properly use it. As a result, the body's tissues cannot use glucose for energy, and the sugar builds up in the blood and urine.
Veterinarians say that while obesity clearly is linked to diabetes in pets, it appears to contribute to the disease differently in cats and dogs.
Fat cats are prone to diabetes because they develop insulin resistance, meaning their bodies don't effectively use insulin. As a result, the pancreas pumps out more insulin as well as another hormone called amylin. “When you get too much insulin secreted, you get too much amylin secreted as well, and that tends to aggregate and destroy the insulin-producing cells,” says veterinarian Richard W. Nelson, a professor at the University of California School of Veterinary Medicine in Davis.
With dogs, obesity is associated with an increased risk of pancreatitis — an inflammation of the pancreas — which can then lead to diabetes because the body doesn't make enough insulin, according to a report by Jacquie S. Rand, a diabetes expert at the University of Queensland’s School of Veterinary Medicine in Brisbane, Australia.
'Catkins' diet and other aids
Not every dog or cat that develops diabetes is fat, but any way you look at it, obesity and diabetes are linked. The good news is that obesity is preventable and reversible, and oftentimes so is the diabetes.
A change to a high-protein, low-carbohydrate diet — nicknamed the “Catkins” diet — can promote weight loss and make diabetes more manageable in cats, often sending them into remission so that they no longer require insulin injections. At the Windsor Veterinary Clinic in Colorado, three out of every four diabetic cats have their disease controlled through diet alone, says Downing.
Diet can help manage the disease in dogs so that they need less insulin, but it doesn’t have as dramatic an effect as it does in cats.
“We don’t see dogs go into remission after dietary change, whereas that happens fairly frequently in cats,” says veterinarian Michael Stone, an assistant clinical professor of veterinary medicine at Tufts University in Grafton, Mass.
Besides diet, improvements in insulin have made it easier for owners to manage diabetes in dogs and cats. Veterinarians now have two newly approved forms of insulin, one for cats and one for dogs, that make treatment better. Vets also are finding that some diabetic cats respond well to a long-acting human synthetic insulin called glargine, which appears to work best in newly diagnosed diabetic cats that are being fed a high-protein, low-carb diet.
Another important development has been the ability of owners to check a pet’s blood glucose level at home using a blood glucose meter. That makes it a lot easier to ensure that a pet is receiving the right amount of insulin, without subjecting it to a stressful overnight stay at a veterinary clinic.
A preventable disease
Downing wants pet owners to know that diabetes is almost always a preventable disease if a pet maintains a normal weight. She stages interventions — advising clients with fat pets about the risk their animals face — and runs a pet weight-loss program.
“We treat this just like Weight Watchers,” she says. “We have regular weigh-ins, we create a food program and an exercise program, and we give regular feedback to the owners about what a good job they’re doing.”
What happened with the little Australian Terrier?
“We sent him home,” Hamil says. “We put him on insulin over the weekend and changed his diet. Once we have diabetic patients regulated, we find that the vast majority of them do very well.”
Kim Campbell Thornton is an award-winning author who has written many articles and more than a dozen books about dogs and cats. She belongs to the Dog Writers Association of America and is past president of the Cat Writers Association. She shares her home in California with two Cavalier King Charles spaniels and one African ringneck parakeet.