28 | How to feel confident nursing diabetic cats in 5 simple steps

PodcastEndocrine
Written By Laura Jones

Ever felt unsure advising diabetic cat clients?

 

Ever felt confused about what to feed?

Wondered why we tend to use specific types of insulin for our cats?

Or felt boggled by the new oral treatments available, and how they work compared to insulin?

Well, in today’s episode of the Medical Nursing Podcast, I’m diving DEEP into feline diabetes - so you’ll leave this episode with all your questions answered.

Want to know even more about diabetes? I’ve got you covered.

In the last episode, I announced that I’d be hosting a webinar to accompany this podcast series, and you’re invited to join me! 

Join me for a 90-minute session demystifying diabetes on July 10th, where we’ll explore:

  • How the endocrine pancreas is supposed to work, and what happens when it goes wrong

  • How diabetes differs between cats and dogs, and why this is important in how we treat and nurse them, and in the advice we give our clients

  • What signs we see in diabetic patients, the typical findings on their physical examination, and the conditions and lifestyle factors that can cause diabetes

  • The common tests performed with diabetic patients, how to interpret them, and what they tell us

  • The treatment options for diabetes and how they differ between cats and dogs - including the different insulins available, how to use new SGLT2 inhibitors for cats, what to feed your diabetic patient, and more

  • How to monitor your patient’s response to treatment, including advanced monitoring options like continuous glucose monitoring and haemoglobin A1c monitoring

  • How diabetic ketoacidosis occurs, and how we diagnose, treat and manage this diabetic emergency

  • The nursing skills we can use when managing diabetic patients

    The session will be hosted live at 7.30 pm (UK time), and the recording, quiz and CPD certificate will be available to everyone registered after the event.

    Save your spot now!

    I cannot wait for this—it is the first public webinar I’ve hosted in over a year, and I’m jam-packing it with SO much information—you won’t want to miss it!

But enough of that for now - let’s get into feline diabetes

Diabetes is the second most common feline endocrinopathy, and though it can be seen at any age, most cats are > nine years old at the time of diagnosis. 

Most diabetic cats have insulin-resistant diabetes, unlike dogs, which tend to have insulin-deficient diabetes.

Type 1-like diabetes is rare in cats; in fact, we estimate that approximately 80% of diabetic cats have type 2-like diabetes, which results from a combination of impaired activity of insulin in the liver, muscle, and fat tissue (known as insulin resistance) and failure of the beta cells to produce insulin effectively.

So, whereas most dogs have beta cell destruction, most cats have beta cell failure - meaning their beta cells have the potential to release insulin - they’re just not doing it well enough right now.

And that’s really important for us to know because it means that, if we manage these patients correctly, we can get them into remission and return them to a pre-diabetic state.

What causes diabetes in cats?

In most cases, we don’t know exactly what causes those beta cells to fail - some cats have a reduction in the number of beta cells, others have immune-mediated inflammation (though this is rare), but most have a combination of beta cell failure and insulin resistance, which is compounded by glucose toxicity.

Glucose toxicity is where the chronically high glucose levels in the bloodstream (as a result of beta cell failure and insulin resistance) directly affect the pancreas, reducing the number of functional beta cells and causing permanent pancreatic damage.

So that’s 80% of our diabetic cats - but what about the other 20%? Well, the remaining feline diabetes cases we see are due to specific underlying causes - including

  • Pancreatitis

  • Pancreatic lesions

  • Steroid administration

  • Cushing’s disease (Cushing’s in cats is rare, but over 80% of Cushingoid cats have concurrent diabetes)

  • Acromegaly (excessive growth hormone release)

What signs do we see in these patients?

Like our diabetic dogs, we classically see polyuria, polydipsia, polyphagia, and weight loss due to glucosuria, osmotic diuresis, and an inability to use glucose as an energy source in the body.

Cats may also present with evidence of diabetic neuropathy - this is usually seen as a plantigrade stance, where they walk on their hocks, and is because their hyperglycaemia affects the peripheral nervous system.

If we don’t spot the signs of diabetes early enough, we can see many consequences of unregulated diabetes - including ketoacidosis, hepatic lipidosis, and systemic hypertension.

And how will we diagnose it?

Just like our diabetic dogs, we’ll perform a variety of tests to diagnose diabetes in our cats, including:

  • Biochemistry

  • Fructosamine

  • Haematology

  • Urine analysis, including culture

  • Ketone measurement (blood and/or urine)

  • Venous blood gas (if available)

  • +/- Thoracic and abdominal imaging - especially if your patient is anorexic, hyporexic or is a hard-to-stabilise diabetic

And what do we usually see in our results?

Persistent hyperglycaemia and glucosuria are diagnostic for diabetes mellitus. In cats, differentiating between true hyperglycaemia and stress hyperglycaemia can be hard. Stress causes marked glucose release, causing significantly elevated blood glucose levels, which can cross the renal threshold and enter the urine in some cases, persisting for several hours.

This is where fructosamine testing can be useful. Fructosamine is a glycated protein (meaning it is formed from glucose) and is not affected by stress hyperglycaemia, so it can be used to differentiate between the two in a potentially diabetic cat.

So we’ve diagnosed our patient, but how do we treat them?

Just like dogs, when we manage feline diabetes, we want to resolve the patient’s clinical signs whilst avoiding clinical hypoglycaemia. But in cats, we have one more goal - to achieve diabetic remission where possible.

Now, this needs to be done through strict glycaemic control because we have quite a short window to do this. The longer our patient’s glucose levels are high, the more opportunity for glucose toxicity and permanent pancreatic damage.

Our treatment options for cats differ compared with dogs. We’ll need to:

  • Provide exogenous insulin OR an oral hypoglycaemic agent

  • Feeding them an appropriate diet to reduce pancreatic demand

  • Withdrawing contributing medications

  • Managing contributing conditions

Let’s start by looking at insulin

Longer-acting insulins are generally used in cats compared with dogs. We often find that lente insulin has a shorter peak effect and duration of action in cats, meaning that it doesn’t work for long enough to appropriately control their diabetes in some cases.

For this reason, we tend to use protamine zinc insulin as a first-line insulin treatment since it works for longer. This is given BID, 12 hours apart in most cases (unless your patient is going into remission and we’re reducing their insulin dose/frequency).

Longer-acting insulin analogues, such as glargine, are also good options for diabetic cats. However, they are used off-license, so they are reserved for hard-to-stabilise cats who do not demonstrate appropriate control on a licensed alternative.

What about oral treatments?

Historically, oral hypoglycaemiant drugs such as glipizide or acarbose were used, but these are not offered as first-line treatments since their clinical response is variable. 

Now, though, new oral treatments are available. I’m talking about gliflozins - at the time of recording, bexagliflozin is available in the US, and velagliflozin is available throughout the UK and Europe.

Gliflozins belong to a class of drugs called SGLT2 inhibitors. These drugs work on the kidneys, inhibiting glucose reabsorption in the renal tubules and promoting glucosuria. 

This means that our diabetic cats essentially urinate out their excess blood glucose, restoring normal blood glucose levels. 

But because they don’t contain insulin, they can only be used in stable, non-ketoacidotic, newly diagnosed cats, as these patients should have sufficient endogenous insulin levels to keep things like ketones at bay. They’re not suitable for pre-existing diabetics in most cases or unwell diabetics (e.g., those who are anorexic, in DKA, or have concurrent diseases like pancreatitis).

Where does diet come in?

Nutrition is a crucial aspect of managing feline diabetes. We need to feed these patients a diet that reduces pancreatic demand for insulin, which means controlling their carbohydrate intake.

Carbohydrates are broken down into sugars, which require insulin for processing. Too much sugar and no insulin equals worsened hyperglycaemia, so we will manipulate carbohydrate content in the diet to minimise this.

In cats, we want to feed them a high protein, low carbohydrate, and complete and balanced diet. We’ll aim for a total carbohydrate intake that’s no more than 12% of the metabolisable energy content of the diet to minimise the demand for insulin.

Unlike dogs, meal timing has little impact on day-to-day glucose levels, so our diabetic cats are free to graze all day if they prefer, rather than requiring half of their requirement strictly every 12 hours. 

If your patient goes into remission, ensure you keep feeding them the same diet—it can help keep them in remission for longer.

What about other strategies for managing feline diabetes?

Many diseases and medications contribute to insulin resistance. In cats, the most common 2 are obesity and acromegaly (excessive growth hormone). Acromegaly is usually treated surgically via removal of the pituitary gland, and obviously, obesity is much easier to treat than that!

But make sure you’re doing what you can to get your diabetic cats to a healthy weight, and in your hard-to-stabilise cats, consider suggesting some testing for acromegaly if this hasn’t already been performed.

Steroid medications are highly associated with diabetes in cats since steroids cause insulin resistance. If possible, try to avoid their use in diabetic or at-risk cats, or taper the dose to the lowest effective one (or consider administering steroids via an alternative route if appropriate, eg via inhaler in an asthmatic cat)

What about nursing care?

Just like our diabetic dogs, monitoring response to treatment and assisting with diabetic stabilisation is a crucial aspect of treating our non-ketoacidotic diabetic cats, and this is an area where we really come into our own as nurses and technicians.

We know our diabetic cats are stressed in the hospital, and this is bad news for monitoring their blood glucose levels - because stress hyperglycaemia is going to make interpreting anything really challenging.

If they’re really stressed in the hospital, we have a few options. We can either:

  • Teach our clients how to perform ear-prick BG testing at home so that they can perform at-home curves

  • Place a continuous glucose monitor for our clients to use at home, giving us up to 14 days of 24/7 data about the patient’s glucose levels.

If neither of these is an option, do whatever you can to minimise stress in the hospital. If possible, use the patient’s things from home so they have some familiarity despite being in an unfamiliar environment. Give them a hiding place so they can take themselves away to a place of safety if they feel the need. And group their treatments and observations together to allow periods of uninterrupted rest.

Like our dogs, the care we give our diabetic cats doesn’t end when they leave the hospital. Client education and training, as well as ongoing nurse clinics, are vital parts of providing long-term nursing care. 

They allow us to rapidly identify changes in a patient’s condition and intervene quickly, improving outcomes and enhancing client compliance with things like insulin administration and dietary changes. All of this means 3 things:

  • More job satisfaction and utilisation of our nursing skills

  • Improved quality of life for our patients

  • An improved chance of achieving diabetic remission for our patients

So there you have it! 5 steps to feeling confident when nursing our diabetic cats. First of all, we need to know how the disease works and how the pathophysiology differs from canine diabetes. Then, we need to spot the signs and know what to look for on our examination before thinking about those diagnostic tests. Once our patient is diagnosed, it’s all about treatment (either a long-acting insulin or oral treatment, depending on the individual case, along with adjusting the patient’s diet and managing any related conditions) and then providing ongoing nursing care.

Thanks so much for learning with me for another week. In our next episode, we’ll be diving deep into diabetic ketoacidosis, looking at how this differs from “stable” diabetes and all of the nursing skills we can use with our DKA patients. Don’t forget to save your spot at the demystifying diabetes webinar if you haven’t already, and I’ll see you in the next episode!

Did you enjoy this episode? If so, I’d love to hear what you thought - screenshot it and tag me on Instagram (@vetinternalmedicinenursing) so I can give you a shout-out and share it with a colleague who’d find it helpful!

Thanks for learning with me this week, and I’ll see you next time!

References and Further Reading

Laura Jones
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27 | The top 5 things you need to know about canine diabetes