By Anna Dunton-Gallagher
Off the leash
Lately I have been dealing a lot with the not-so-sweet side of too much blood sugar. Otherwise known as diabetes, excess blood glucose causes many issues in our pets. It is often diagnosed later than in humans, since our pets can’t say they feel a little dizzy or have to pee a lot. This means that we are already dealing with side effects of bladder infections, muscle loss and sometimes very ill pets. I will talk about things that may be a warning for diabetes, and how to deal with the diagnosis.
Cats tend to get a diabetes more similar to human Type 2 diabetes. We see this most often with overweight cats. It can also happen in pets that have had chronic steroids administered. In most cases, the body stops responding to the insulin put out by the pancreas, and in some cases, the pancreas stops making enough. Therefore, when the pet’s blood glucose rises, there is not proper response to lower it. That means that the body constantly has too high a level of blood glucose and no means to lower it by itself.
A red flag is a cat who is overweight and loves to eat suddenly losing weight and changing their eating habits. They will start to drink much more, though this can be hard to tell in cats. Since we are very familiar with our indoor cat’s bathroom habits, many owners notice that they are scooping the litter box more frequently and that there is much more urine present. Sometimes it even becomes difficult to keep up with scooping the box, and cats will start to urinate outside of the box because they don’t want to use a dirty box.
Dogs most commonly do not produce enough insulin in the pancreas, leading to diabetes. This can be caused by being overweight, but often happens to normal-weight dogs too. We begin to notice many of the same changes as in cats — like increased thirst and urination with weight loss. Dogs also commonly develop cataracts secondary to diabetes, so you may notice their vision changing. When dogs start drinking more we usually know, as the bowl is constantly empty. We also know when they start to urinate more, as we have to take them out much more than usual.
As diabetes causes hyperglycemia (which is increased blood sugar), the brain and other organs are not getting enough glucose to fuel them. When the glucose stays in the blood it is unable to feed other parts of the body. Insulin is the trigger to move glucose out of the blood stream and into other parts of the body.
The brain then signals the body that it needs more energy, and the body begins to break down fat and muscle tissue. In dogs (and rarely cats), this can cause them to suffer what is known as diabetic ketoacidosis. Diabetic ketoacidosis (or DKA) is a life-threatening condition. They must be treated with IV fluids and fast-acting insulin. The pH of the bloodstream begins to change, which alters their acid-base and electrolyte status. This is essentially a last-ditch reaction for the body to fuel the brain however it can.
Uncomplicated diabetes is hyperglycemia (too-high blood sugar) without DKA. This is treated with injectable insulin at home, and diet change. The faster diabetes is diagnosed the less effect it has on the liver and pancreas. In animals with high blood sugar, the excess spills over into the urine. This then creates an environment that is perfect for bacteria. These pets often get secondary urinary-tract infections which can harm the bladder and kidneys if not treated. When we see glucose in the urine it is an immediate red flag for diabetes.
In some pets, diabetes is controlled very quickly, while in others control can take quite a while. Dogs tend to have somewhat slower control than cats. Insulin should be changed in slow increments. Since pets who have too low a level of blood sugar can become comatose, we never want to adjust the insulin too quickly.
Diabetes can lead to secondary problems, so controlling blood glucose is important. Ideal blood sugar is around 100, but we are often happy with a range between 80 and 200. Often in cats we can revert their insulin status, which means we can convert them back to being not diabetic. This is done with food changes, and often a short course of insulin. Some cats do not convert, and we rarely achieve conversion in dogs.
As always, any behavior, eating, drinking, bathroom or weight changes in your pet should be investigated. Controlling weight in cats is an important component to preventing diabetes. Though we can still see this disease in animals with a perfect body condition score, obesity is a big risk factor in cats. Too much sweetness in the blood leads to many other problems, so make sure you contact your veterinarian with any changes in your pet.