Diabetes in Cats: Causes, Signs & Treatments

What is feline diabetes?

Diabetes (diabetes mellitus) is a condition that develops when your cat cannot use sugar (glucose) effectively or control the sugar levels in the blood. Insulin, a hormone made in the pancreas, regulates the use and storage of blood glucose, taking it from the blood into the cells where it is needed. Picture it like a parent picking up a toddler from nursery and taking them home. Insufficient insulin production is potentially life-threatening.

What causes diabetes in cats?

There are two broad ways that diabetes occurs. The first is that the body’s immune system starts attacking the insulin-producing cells of the pancreas. This is irreversible and is more common in dogs than cats. The second, which is the most common type of diabetes in cats, is where the body’s cells become more resistant to insulin. This means the pancreas has to work harder to produce extra insulin. Over time, the cells become exhausted and insulin production starts to decline. This is particularly the case with overweight and obese cats. This type of diabetes can sometimes be reversed with prompt diagnosis, treatment and weight loss.

Other factors that increase the chance of your cat developing diabetes include:

• Body condition. Overweight cats are much more likely to develop diabetes. Severely obese cats are most at risk.
• Age. Cats can develop diabetes at any age, but peak onset is around 8 years.
• Gender. Diabetes in cats is more prevalent in males.
• Breed. Burmese are more at risk than other breeds.
• Other factors. Poor nutrition and hormonal abnormalities can increase risk.

Signs of diabetes in cats?

The signs of diabetes are difficult to recognise because they are similar to those of other disorders, like chronic kidney disease and hyperthyroidism. If you notice any of the following, it could mean your cat has diabetes.

Signs and symptoms of diabetes:

• Increased thirst and urination

• Weight loss

• Not eating 

• Increased appetite

• Tiredness

• Weakness 

• Lethargy 

• Vomiting

• Depression

• Abdominal pain

If your cat shows these symptoms, they could be diabetic.

Diagnosing feline diabetes

Your vet will want to do blood tests and analyse a urine sample. Because of the lack of insulin taking glucose from the blood into the cells, the blood sugar level gets higher and higher. The kidneys play a major role in keeping the levels of sugar and other nutrients in the blood at a normal, safe level. This is called ‘homeostasis’. The kidneys start to excrete extra sugar into the urine to try to lower the levels in the blood. Imagine this like the overflow hole in a sink. This is why diabetic animals and humans have sugar in their urine. 

The blood tests will make sure there is nothing else going on at the same time and look at the level of glucose in your cat’s bloodstream. Some healthy cats will have a high glucose level just from the stress of going to the vet’s, so your vet may look at a longer term marker called fructosamine. They may also want to do a series of blood tests or ask you to do some pin prick blood tests at home, where your cat will be more relaxed and the results are more reliable. There are also devices available now that are implanted in the skin and continually monitor your cat’s glucose. These are useful in both the diagnosis stage and monitoring the effectiveness of treatment afterwards.