Diabetes in cats is very similar to diabetes type 2 in human. It is characterized by a resistance to insulin of all the body cells and by impaired insulin secretion by the pancreas. As for human, obesity is the main explanation of the rapid increase of diabetes in the cat population. Happily, diabetes is far better managed than in the past and lethal outcomes have dramatically decreased.
Initially insulin resistance is caused by obesity, the absence of physical activities or the use of some medications (glucocorticoids, progesterone derivatives). Neutered cats are more likely to get diabetes because they are more prone to gain weight after they have been spayed.
Then, to compensate for the decreased sensitivity of the body to insulin, the pancreas secretes more of it. At the same time, amylin is secreted also in greater quantities. It aggregates in fibrils and concentrates within the β cells of the pancreas. The resulting amyloid fibrosis causes β cells progressive destruction, and insulin secretion impairment.
If diagnosed early enough, before the pancreas is too damaged, diabetic cats can go into remission through a diet aimed at bringing their weight down and oral hypoglycemic drugs. Beyond this stage, the diabetes will become chronic and will require daily insulin injection(s). As for dogs, cats, if well taken care of, can live a normal and happy life.
Some symptoms of diabetes in cats are nonspecific and can be found in many other diseases: Increased urination (polyuria), increased thirst (polydispsia), lethargy, unkempt hair coat, increased hunger (polyphagia). Other signs are more suggestive of diabetes: stance on the hocks, hind limb weakness, and loss of the cat’s ability to jump.
The first goal of cat diabetes therapy is to make it go into remission. It is possible if the cat is treated soon enough with aggressive insulin therapy combined with a proper diet. If diabetes persists after a period or 4 to 6 weeks, a remission is no longer possible. The goal of the treatment changes and is aimed at suppressing symptoms and avoiding dangerous complications (diabetic ketoacidosis, diabetic nephropathy, hepatic lipidosis, ocular disorders, increased infections sensitivity…).
Some diseases are more frequent in diabetic cats than in healthy cats. They are called concurrent diseases: hyperthyroidism, kidney and heart diseases, Cushing’s disease… No cause-and-effect relationships between these diseases and diabetes have been explained yet. However, your vet will have to carry out examinations to detect their possible presence in your cat.
Daily insulin injections are the mainstay of diabetes treatment. Type of insulin and frequency of injection are tailored to the individual cat.
Diet is the second important part of the treatment. It is aimed at correcting nutritional unbalances that lead to obesity and at decreasing the body needs for insulin.
Home monitoring: as the response of the cat to the treatment changes over time, your vet will ask you to monitor regularly your cat’s glycemia, weight, feeding behavior and symptoms.