Ask the Vet
Dealing with Diabetes
Question: My elderly cat has just been diagnosed with diabetes. He is very independent and often resents handling. I am worried that injecting him daily may prove impossible and wondered if there was any alternative. Also how long would he live without treatment?
Answer: Glucose, a sugar, is a vital source of energy for most cells in the body. The digestion of food releases glucose into the bloodstream and stimulates the production of the hormone insulin in the pancreas. Insulin acts as a ‘key’ which opens doorways and allows glucose into the cells. In diabetes mellitus, there is plenty of glucose in the bloodstream but the cells can’t be unlocked either because there is a lack of insulin, or because the insulin is being prevented from exerting its activity on the cells. The glucose has nowhere to go, so blood levels continue to rise and clinical signs develop. Although diabetics have more than adequate glucose, it is in the wrong part of the body. It can’t get into the cells, so the cat continually feels starved. Cats that drink a lot of water, urinate frequently, are always hungry and are losing weight despite eating increased quantities of food may be showing signs of diabetes.
Unfortunately, for most cats, control of diabetes can only be achieved by giving daily insulin injections. The thought of injecting frightens the life out of most owners, but you will hopefully rapidly gain confidence when you see how well your cat copes with the procedure. The insulin needles are so fine that cats are usually unaware of anything happening when the injection is carried out, and this is best administered when your cat is eating, as with any luck he will be too absorbed in his food to pay much attention. At the clinic we always take our time to show owners how to inject, and supervise their attempts until both sides are happy for the cat to be injected at home. Some cats will need injections twice daily but others can do well on once-daily injections. Owners have to be prepared to subject themselves and their cats to a change in lifestyle because of the necessarily strict regimen. In most cases, this is not as onerous as owners fear. Most of us have some sort of Monday to Friday routine anyway, so a little bit of juggling of the social life at the weekend is all that is required. We also have to accept that our patients don’t know they’re supposed to be on a fairly strict timetable, so the odd hiccup in administering an injection because our patient is sitting on top of the garden shed isn’t the end of the world! If, however, you or your cat would struggle to find some sort of reasonable daily routine, you may have to review the use of insulin.
Although there is no alternative to daily injections for the majority of cats, certain common medications can occasionally induce diabetes, which may be reversible when the therapy is stopped. Some very obese diabetic cats can be stabilised and even weaned off insulin if they can slim down. If the body overproduces certain counteracting hormones, such as growth hormone, cortisone or thyroid hormone, then this too can induce Diabetes. Treatment of these co-existing conditions may reduce a pet’s insulin requirement or be curative altogether.
We always have to advise owners that even with treatment a diabetic cat may only have a life expectancy of two years, but we have been happy to be proved wrong by many of our patients who have gone on to have several years of life and, importantly, an excellent quality of life. Without treatment the body will decline rapidly within days or weeks, and liver failure will ensue. Although a diagnosis of diabetes is quite daunting, owners can find it very rewarding to treat, and an unexpected bonus is that they often develop a much closer bond with their pet.