This is the third and final instalment of a 3-part blog series about diabetes in pets. The first article explored the signs and symptoms of diabetes in pets, the second highlighted the best ways to treat diabetes in pets. In today’s article, we will cover how to monitor their diabetes and blood sugar levels in 6 ways.
There are a number of ways your pet can be monitored for how well their diabetes mellitus (DM) is being controlled with their insulin. Let’s go through each option and identify the pros and potential cons for each.
At the end of the day, your veterinarian will want to make sure your pet’s weight has gone back to normal, and that their appetite, thirst and demeanour or energy levels have all gone back to normal too. These are all signs of good diabetic control.
** IMPORTANT: Only your veterinarian can advise you on whether your pet should have their individual insulin dose adjusted. The following information serves only as a guide. For more detailed information on each of these glucose monitoring tools we encourage you to see your veterinarian.**
There are a number of ways to monitor your pet’s diabetic control and their blood sugar (glucose). Whatever the numbers, remember they are always looked at in conjunction with signs of diabetic control- your pet’s body weight, thirst, appetite and demeanour/energy.
1. Keep a diary of your diabetic pet’s signs
This includes their appetite, thirst and overall demeanour. Here are some links below for samples of pet diabetes diaries:
Pros – Keeping a diary about your diabetic pet costs you nothing but a little bit of your time each day to fill it in.
Cons – Some owners might not feel like they have the time to do this.
2. Urine testing
This is when a small test strip is placed in your pet’s urine to measure urine glucose levels as well as urine ketones. These Keto-diastix reagent strips are perfect for this.
For dogs and cats receiving insulin, it is normal to have some glucose present in their urine. Urine dipsticks do not replace the glucose monitoring techniques that are listed below but do provide information in particular instances – such as the detection of ketones. It is never normal for your pet to have ketones in their urine. If your pet does have ketones in their urine please see your veterinarian as soon as possible especially if your pet is showing any signs of being unwell. The presence of ketones in your pet’s urine indicates poor diabetic control.
Pros – This is definitely one of the cheapest of all the monitoring options and is very easy to use in dogs.
Cons – It is only an indirect measure of diabetic control and can be challenging to capture and measure the urine in cats. For cats, you can purchase some special non-absorbent litter, or get a litter tray with a pan underneath to capture the urine for you to be able to test it.
3. Home blood glucose monitoring
This is where you use a portable glucose reader and a small lancet device. Veterinary-specific blood glucose monitors (glucometers) such as AlphaTRAK should be used if you would like to do this. Veterinary glucometers such as the AlphaTRACK are specifically calibrated and validated for dogs and cats so you can trust that the glucose readings are accurate. Only a tiny amount of blood is needed -literally a drop, just 0.3uL!
To easily get a sample of blood from your pet for a glucose test, all you need is a drop of blood from either your pet’s paw or their ear.
Pros – Your pet is more likely to be calm and relaxed at home and won’t have the stress they might otherwise have if they had a blood glucose curve performed in the vet hospital. Once you and your pet get used to home blood glucose testing, you may find this to be an easier, less stressful option. After your initial set-up costs of acquiring your glucometer, this is the next cheapest blood glucose monitoring option. You will need to send your veterinarian the glucose numbers that you receive which will normally entail some re-check fee for them to interpret the result and advise you on it.
Cons – The initial set up fee (purchasing the glucometer device), and most importantly getting used to pricking your pet’s paw or ear. This isn’t always achievable for all pets and their owners. It is also an extra burden to perform home glucose monitoring and not all owners are available to spend a day at home to do a blood sample every couple of hours on their pet.
4. Fructosamine blood levels
Fructosamine is a marker of protein in the blood that is bound to glucose. It will be elevated when blood glucose has been high for a long time, and normal when blood sugar levels have been more well controlled. It gives an approximate gauge of your pet’s diabetic control over the previous 2 to 3 weeks.
Pros – Is just a single blood test, and cheaper than in-clinic blood glucose curves or continuous glucose monitors (CGMs). It is a reasonable option for you if you can’t get your pet in for a whole day of in-clinic glucose testing, home monitoring isn’t possible, or CGMs are too expensive.
Cons – It doesn’t provide as detailed information as individual blood glucose measurements. If your pet has an abnormal result, further testing is likely to be required to investigate their diabetic control further.
5. Blood glucose curves performed in the vet hospital (over a 10-12 hour period)
This is when 5 or 6 tiny blood draws are collected every 1 to 2 hours over the course of a day from your pet. Your pet would receive their normal breakfast and normal morning insulin dose for that day and you would drop them off first thing in the morning and pick them up at the end of the day.
Pros – You don’t need to try to get blood samples from your own pet.
Cons – You need to take your pet to the vet hospital for the day. If they get stressed by being in the vet hospital their blood glucose readings may be artificially high which can make recommendations around insulin adjustments a bit trickier for your veterinarian to make.
The cost of this is somewhere between home glucose monitoring and the continuous glucose monitor (CGM).
6. A 24-hr continuous glucose monitor (CGM)
This is a device that provides 24-hour, round-the-clock glucose measurements for up to 14 days. In the last 5 years in Australia, veterinarians have been using a human CGM called “Freestyle Libre”. It is a 35mm wide, 5mm high disc that is glued onto your pet’s skin with some tissue glue after the area has been shaved and cleaned. It measures the glucose level in your pet’s interstitial space (the space between their blood vessels), which lags a little bit behind their actual blood glucose level. The CGM is usually placed over your pet’s neck or the side of their chest depending on your pet’s size and your veterinarian’s preference. The sensor can be linked to a reader device or linked directly to your smartphone via an app. CGMs can provide you and your veterinarian with a heap of information, especially in the early days of your pet starting their insulin journey, or after any insulin dose adjustments. You just need to scan the CGM with the reader or your smartphone at least every 8 hours. With the newer version of Freestyle Libre sensors (Freestyle Libre 3), glucose information can be automatically sent to your smartphone every minute, provided it is within range of your pet. Whilst these CGMs have revolutionised how we monitor diabetes in pets, they do have some limitations which you should be aware of.
Pros – CGMs provide the most detailed glucose information about your pet over multiple 24-hour periods and can help provide better information on how your pet’s diabetic control is trending
Cons – CGMs are the most expensive monitoring option, and being a human monitoring system there is no ‘Medicare’ rebate for veterinary patients.
They are not guaranteed to work for the whole 14 days like they are meant to in adult people, and studies into pets using these CGM devices have found that they tend to work for an average of just 8 days in cats (range 1-14 days) and 6 days in dogs (range 3-14 days).
Despite everything you or your veterinarian might do to try to make them stay in place for as long as possible, your pet may still manage to dislodge the sensor early by scratching it off, or they may just come loose by themselves.
Your pet might have irritation or redness where the sensor was after it has come off.
The CGM may be more likely to fail if your pet is too skinny and has lost a lot of weight due to their diabetes.
If the sensor fails, you have to decide whether the expense of buying and applying a whole new sensor is worth it, as the company that makes them (Abbott) will not supply support or refund a faulty sensor. This is because the Freestyle Libre CGMs are registered for use in people, not pets.
Finally, you can sometimes get addicted to scanning your pet’s CGM and this can cause you unnecessary anxiety about your pet’s glucose numbers.
How regularly your pet requires blood glucose monitoring depends on how recently your pet has been diagnosed, how well they are or if their signs are progressing, whether they have had any recent insulin dosage adjustments and whether they are a dog or a cat.
If this article has raised any questions or concerns about your pet’s diabetes, we encourage you to see your veterinarian!