By Dr. Becker
If your cat seems to be thirstier than usual, is urinating frequently, is hungry all the time but also losing weight, you should have him checked by your veterinarian for feline diabetes.
Other signs to watch for include urinating outside the litter box, unusually sweet-smelling breath, lethargy, dehydration, poor coat condition, and urinary tract infections.
Left untreated, diabetes can cause your kitty to lose his appetite and a significant amount of weight, and develop muscle weakness. Uncontrolled, the disease can ultimately result in diabetic neuropathy, a condition in which there is profound rear limb weakness and a plantigrade walk, meaning the ankles are actually on the ground as the cat walks.
Feline Diabetes Mellitus
Diabetes mellitus is unfortunately a too-common disease in older cats, and is especially prevalent in kitties fed dry food diets. In fact, a study published in 2006 in the Journal of Feline Medicine and Surgery1 concluded that high-protein, low-carb diets are as or more effective than insulin at causing remission of diabetes in cats. Since most dry cat food is high in carbs and deficient in high-quality protein, it makes sense that a lifetime of eating kibble could cause diabetes in middle-aged and older kitties.
The pancreas produces insulin based on the level of glucose (sugar) in the blood. Insulin is necessary in order for glucose to enter the cells of the body. When glucose levels are high (which normally occurs after a meal), insulin is released.
When there is not enough insulin being released from the pancreas, or there is an abnormal release of insulin coupled with an inadequate response of the body’s cells to the insulin, diabetes mellitus is the result. Sugar in the bloodstream cannot get into the cells of the body, so the body starts breaking down fat and protein stores to use as energy. As a result, no matter how much the cat eats, she loses weight.
In addition, the glucose builds up in the bloodstream and is eliminated through urination. This leads to excessive urination and thirst.
Diabetes in animals can be either insulin-dependent, or non-insulin dependent. In kitties, the condition usually begins as non-insulin dependent diabetes. In most situations, insulin injections are needed to control elevated glucose levels, but there are some cats that do better with oral hypoglycemic medications.
If feline diabetes is diagnosed early and everyone involved with the cat is committed to bringing the disease under control, it’s quite possible to normalize blood glucose levels and put the diabetes into remission – which means the kitty will no longer need to be on insulin or other medications. But unfortunately, in cats that have been diabetic for a significant period of time, the cells in the pancreas may be worn out and unable to secrete insulin any longer. In this case, the animal may require life-long insulin therapy.
A New Insulin That Can Benefit Diabetic Cats
As I discussed in an article last year about one of my patients, Biddie, a 15 year-old kitty who suffered with seemingly unmanageable diabetes, I tried a relatively new kind of insulin called glargine. Glargine is a DNA-recombinant long-acting insulin analogue. I gradually increased Biddie’s glargine dose over a three-month period until we were able to get his blood sugar under control.
A recent study published in the Journal of Veterinary and Emergency Critical Care2 evaluated glargine as a treatment for diabetic ketoacidosis in cats and showed that the drug successfully treats the condition. Ketones are waste products that result when the body burns fat rather than glucose as fuel. The body attempts to eliminate excess ketones as quickly as possible through urination. If ketones build up in the bloodstream, they can lead to significant energy problems in the body, resulting in diabetic ketoacidosis. This condition is a medical emergency that can progress rapidly, cause severe illness, and if not treated promptly, can be fatal.
According to the study, glargine also achieved remission of diabetes in one-third of patients.
The Importance of the Right Nutrition for Cats with Diabetes
Unfortunately, many veterinarians continue to recommend commercial or “prescription” diets for diabetic cats that are entirely inappropriate. These foods typically contain a small amount of rendered protein and a tremendous amount of fiber. The theory behind these formulas is that low-fat diets force carnivores to burn excess body fat. The problem is that most cats with serious diabetes don’t have any excess fat to burn.
In addition, a diet deficient in high quality protein will force a cat’s body to metabolize its own muscle, which contributes to muscle loss and the rear limb weakness characteristic of diabetic neuropathy.
The ideal nutrition for cats is whole, fresh, unprocessed animal meat, organs and bones, with a small amount of veggies. Unfortunately, since most older cats with diabetes have spent their lives eating processed commercial pet food – typically kibble – it can be an insurmountable challenge to transition a sick kitty with little or no appetite to a new diet.
If this is the case with your cat, I recommend adding as much grain/potato-free canned cat food as possible to your pet’s normal fare. The important thing is to ensure your kitty is eating well each day, and if that means continuing to feed dry cat food, that’s what you should do. Just make sure to also encourage him to eat some canned food as well for the added protein and moisture it provides.
With proper treatment (which almost always includes dietary changes), many diabetic cats can achieve remission. With my patient Biddie, whose diabetes was unresponsive to most types of insulin even at the highest recommended dosages, it took about three years.
The biggest contributor to feline diabetes is, of course, obesity. Pets become overweight through a combination of an inappropriate diet, lack of portion control, and not enough calorie-burning physical activity. If you want to do everything possible to prevent diabetes in your pet, you should focus on keeping your kitty lean. Feed a portion-controlled, moisture-rich, species-appropriate diet and make sure she gets some exercise each day.