The technical term for feline diabetes is diabetes mellitus, also known as “sugar” diabetes for its reference to excess glucose in the bloodstream. It is a complex, but common, disease similar to diabetes in humans, in which the cat doesn’t produce sufficient insulin or doesn’t process the insulin produced by its own body. Insulin is a hormone secreted by the pancreas in small amounts and helps to properly balance the blood sugar (glucose) levels in the blood. Glucose is the fuel that provides energy needed by the cells of the body to sustain life.
The types of diabetes in cats are based on the human classification system.
Type 1 Diabetes
Type 1 form of diabetes is defined as an absolute insulin deficiency. In this form, the pancreas is not able to produce enough insulin to regulate the glucose in the bloodstream, leading to persistent high glucose levels in the blood. This type of diabetes is very rare in the cat.
Type 2 Diabetes
Type 2 diabetes, the most common form of diabetes in cats, occurs when the cells in the cat's body don’t respond to the insulin that is being provided. As a result, the cat becomes hyperglycemic (high blood sugar), which may lead to having excess sugar in the urine.
No test can differentiate between Type 1 or Type 2 diabetes in the cat.
Type 3 Diabetes
Type 3 diabetes is also less common and may occur due to other conditions (e.g., secondary to another primary disease which may damage the pancreas).
While diabetes can affect any cat, older, obese and neutered male cats are more commonly associated with the disease. In addition, chronic pancreatitis, hormonal diseases and certain medications have shown a link to increased incidence of diabetes.