What is Diabetes Mellitus in Cats?

Introduction

After observing her normally energetic and curious Bengal cat, Simba, becoming increasingly lethargic and drinking water more frequently than usual, Lisa grew concerned about his health. Prompted by these unusual symptoms, she took Simba to the veterinarian for a comprehensive examination. The veterinarian performed a series of tests and diagnosed Simba with diabetes mellitus, a condition that can affect cats of all breeds and ages.

Diabetes mellitus in cats is a common disease when the pancreas doesn’t produce enough insulin or the body cannot use insulin properly. Insulin helps control blood glucose levels. Diabetes causes high blood glucose levels. High blood glucose levels cause damage to many parts of the body, including the eyes, kidneys, nerves, heart, skin, and blood vessels.

Cats can develop DM because they cannot usually process carbohydrates. This means they must eat large amounts of carbohydrate-rich foods to keep their blood glucose levels regular.

If left untreated, DM can lead to blindness, kidney failure, nerve damage, amputation, and death. Therefore, cats with DM should be treated promptly. Treatment includes dietary modification, exercise, and medication.

Complications associated with diabetes mellitus include ketoacidosis, renal failure, and ulcers.

• Ketoacidosis is characterized by low blood pH, high blood sugar, and ketonemia. Ketoacidosis can occur when insulin levels drop below the level needed to control blood sugar.
• Renal failure results from prolonged exposure to high blood sugar levels. In this case, the kidneys do not filter waste properly, accumulating toxins in the blood.
• Ulcers result from damage to the lining of the stomach and intestines. Ulcers can cause bleeding and infection.

Two Types of Diabetes Mellitus in Felines

• Type 1 Diabetes Mellitus

Type 1 diabetes mellitus is an autoimmune disorder caused by destroying pancreatic beta cells. Beta cells secrete insulin, a hormone that regulates blood glucose levels. If these cells are destroyed, the cat becomes diabetic.

In addition to destroying beta cells, the immune system attacks the liver, causing inflammation and scarring. As a result, the liver fails to remove toxins from the bloodstream.

Because cats lack the enzyme required to break down carbohydrates, they absorb too much glucose from food and drink. As a result, their blood glucose level rises, leading to hyperglycemia.

This causes ketones to form in the urine, resulting in ketonuria. Ketonuria indicates that the cat has developed acidosis, a metabolic imbalance that results in excessive amounts of lactic acid in the blood.

The liver produces ketone bodies to compensate for the increased glucose entering the body. Ketone bodies enter the bloodstream and travel to the kidneys, excreted in the urine.

When the kidneys fail to eliminate ketones, they accumulate in the blood and tissues, causing severe complications. These include blindness, kidney failure, and coma.

• Type 2 Diabetes Mellitus

Type 2 diabetes mellitus develops when the body produces insufficient insulin, or the cells become resistant to insulin. Insulin helps control blood sugar levels.

Insulin resistance is a normal part of aging but can lead to diabetes mellitus. In addition, obese cats are prone to developing insulin resistance.

As cats age, their muscles become less responsive to insulin, which makes them more susceptible to diabetes mellitus. Although cats can develop either type of diabetes mellitus, most cases are due to type 2 diabetes mellitus.

Some cats develop type 1 diabetes mellitus after receiving a vaccine against the feline leukemia virus (FeLV). FeLV infects the lymphocytes of cats, causing the immune system to attack the beta cells in the pancreas.

Other conditions associated with diabetes mellitus include obesity, hyperthyroidism, hypothyroidism, adrenal gland tumors, kidney disease, and fatty liver disease.

Causes of Diabetes Mellitus in Cats

Cats are prone to developing diabetes mellitus because of their unique anatomy. Between 0.2% and 1% of cats will develop diabetes at some point. Their pancreas produces insulin, but unlike humans, cats’ pancreases make two types of insulin instead of just one. As a result, cats need twice as much insulin to regulate blood glucose levels as dogs.

• Obesity is a risk factor for developing diabetes mellitus because they’re prone to insulin resistance. Insulin resistance occurs when fat cells become resistant to the action of insulin. Fat cells store excess energy in triglycerides, which are converted to fatty acids and stored in the liver. When there’s too much-stored fat, the body resists the effects of insulin, leading to elevated blood glucose.
• Another possible risk factor for diabetes mellitus is age. Older pets may be predisposed to develop diabetes due to decreased sensitivity to insulin. However, this isn’t usually the case. Most older animals with diabetes mellitus have been diagnosed with other conditions, such as kidney failure or cancer.
• Diet plays a role in diabetes mellitus development. Some foods contain ingredients that trigger inflammation, which increases insulin resistance and lowers blood glucose. Foods containing these inflammatory compounds include red meat, fried food, processed meats, refined grains, and dairy products. Other dietary factors contributing to diabetes mellitus include excessive consumption of sweets, fats, and alcohol.
• Some medications can also lead to diabetes mellitus. These include corticosteroids, antihistamines, antacids, and certain antibiotics. Your veterinarian should be able to tell whether your cat is taking any of these drugs.
• Finally, genetics play a role in diabetes mellitus development. Certain breeds of cats are known to be predisposed to diabetes mellitus. Be aware that diabetes mellitus doesn’t necessarily mean your cat has type 1 diabetes mellitus. Type 2 diabetes mellitus is far more common than type 1.

Clinical Signs of Diabetes Mellitus in Cats

Diabetes mellitus symptoms vary depending on which type of diabetes a cat has. In the early stages of DM, signs may only appear several weeks have passed. Symptoms of both types include excessive thirst, increased urination, weight loss, lethargy, vomiting, and diarrhea; some dogs and up to 50% of cats present with decreased appetite and frequent infections.

Cats who are obese are more prone to developing diabetes. Obesity causes insulin resistance, meaning it takes longer for the body to use insulin to move glucose into cells. In addition, overweight cats often have fatty livers, which makes it harder for the liver to process glucose.

• Type 1 cats have no warning signs before they develop diabetes. They don’t feel hungry and often lose interest in food. This causes them to lose weight and feel weak. Their urine becomes cloudy and dark yellow. Blood tests show high blood sugar levels.
• Type 2 cats start showing symptoms after being overweight for several years. These cats may not drink as much water as usual—urine changes from clear to amber. In addition, blood tests show high glucose levels.

What Should I Do if My Cat has Diabetes Mellitus?

If your cat develops DM, there are several things you should consider doing.

1. Take them to the vet right away.
2. Feed your cat a diet with plenty of fiber, protein, vitamins, and minerals.
3. Keep your cat active. Exercise helps his body burn calories and lose weight.
4. Monitor your cat’s food intake carefully. Overfeeding can lead to obesity, which increases the risk of DM.
5. Talk to your veterinarian about treating your cat’s DM. Some medications help control the symptoms of DM, and some work better than others. Your vet may recommend insulin injections, dietary supplements, or both.

Diagnosis of Diabetes Mellitus in Cats

Diagnosing diabetes mellitus in cats is pretty straightforward. Blood and urine samples will be needed so the vet can best extract all the necessary information. The blood tests measure glucose levels, fructosamine levels (which help show longer-term trends in glucose control), potassium, triglycerides, and hepatic enzymes.

Urine tests are to test for ketones and to check the urine’s specific gravity. Other helpful diagnostic tests include imaging (ultrasounds or CT scans) to look for changes in the pancreas size and shape indicative of diabetes.

The followings are for further understanding of tests used to diagnose:

1. Blood Glucose Test (BGT): This test measures the amount of glucose in the blood. High blood glucose levels indicate that the cat has diabetes mellitus.
2. Urinalysis: This test checks for proteinuria, glucosuria, ketone bodies, and specific gravity in urine. These results help determine whether the cat has diabetes mellitus.
3. Feces analysis: This test examines feces for fat content, sugar content, and pH. It also looks for parasites and bacteria.
4. Urine culture: This test checks for infection by bacteria, fungi, yeast, and viruses.
5. Glucose tolerance test: Vets measure blood sugar levels over several hours. The GTT measures the cat’s ability to metabolize glucose.

These tests are performed to rule out other possible medical issues. For example, hyperthyroidism in cats may have increased urination due to the thyroid gland overproducing hormones.

Stress, diet, and exercise are other factors affecting these tests’ results.

Treatment of Diabetes Mellitus in Felines

The goal of treatment is to prevent complications of feline diabetes. Treatment options include diet modification, oral medications, and insulin injections.

• Dietary Modification

Many owners find that changing their pet’s diet to a low-carbohydrate or higher-fat diet can significantly improve blood sugar levels.

However, some pets cannot tolerate particular ingredients in commercial diets, so homemade diets must be prepared specifically for these pets.

Some cats are managed at home with dietary therapy and insulin.

• Oral Medications

Metformin is the preferred initial treatment option for diabetic pets. Metformin decreases intestinal absorption of sugar and improves liver function.

Metformin is typically given once daily in the evening. Side effects include nausea and diarrhea.

Glucagon can be used for pets that fail to respond to metformin. Glucagon stimulates hepatic gluconeogenesis and decreases blood sugar levels by increasing the release of stored glycogens from the liver.

Side effects include hypotension, hypoglycemia, and gastrointestinal distress.

• Insulin Therapy for Severe Cases

Insulin therapy is indicated when oral medications fail to manage blood sugar levels adequately. Short-acting insulins provide immediate relief, whereas intermediate-acting insulins provide longer-lasting benefits. Insulin dose depends on the severity of diabetes.

• Other Types of Insulin

Several other types of insulin are available for treating feline diabetes, including zinc insulin, protamine zinc insulin, and ultralente insulin. However, these drugs are rarely used.

Vets will determine if your cat needs insulin injections. First, your veterinarian will perform a physical exam and check your cat’s blood glucose level. He may recommend testing your cat’s blood every week for the first month, then once a month for the next few months. After that, he may test your cat monthly.

Once your cat’s blood glucose levels are under control, you can reduce the amount of insulin he receives. You can also stop giving him insulin altogether. This means your cat won’t get any shots, but he still needs to eat a special diet.

Your cat’s condition will be monitored closely by your veterinarian. The frequency of visits depends on how well your cat responds to treatment.

Prevention of Feline Diabetes Mellitus

To prevent your cat from getting diabetes, you can:

• Keep your cat indoors. Outdoor cats are more likely to get sick.
• Feed your cat a healthy diet. Cats who eat too many fatty foods are more likely to develop DM.
• Make sure your cat gets enough exercise. Regular activity burns extra calories and reduces stress.
• Watch what you put in your cat’s bowl. Some commercial diets contain ingredients that increase your cat’s risk of developing DM.

Because diabetes mellitus is caused by multiple factors, prevention is critical. Diet plays a significant role in preventing diabetes mellitus.

Pets with diabetes mellitus should avoid foods containing added sugars, starch, and carbohydrates. Instead, feed pets a diet rich in protein and fats.

Regular exercise helps maintain normal blood sugar levels. Exercise also improves overall health and reduces stress.

Weight Loss Tips

1. Ensure your cat gets regular checkups at a pet slimmer’. Your veterinarian can advise you about the best diet for your cat based on age, size, and activity level. If your vet recommends a prescription diet, make sure that you follow the instructions carefully.
2. Many cat diets, including dry and wet varieties, are available. Dry diets are easier to digest, while wet diets are better suited to pets with sensitive stomachs. Some cats prefer a combination of both types of food.
3. Be aware that cats require different amounts of protein depending on their age. For example, younger kittens need a lot more protein than older animals. So keep track of your cat’s weight and feed accordingly.
4. Cats typically do not have the same appetite as humans, so you might want to adjust your feeding schedule. For example, you could offer one meal per day rather than three.
5. Try to limit the number of carbohydrates your cat eats. Carbohydrates cause digestion problems in cats, especially those prone to pancreatitis.

Frequently Asked Questions