BY: SAMANTHA BARTLETT, DVM
Recently, at the AVMA Virtual Convention, the subject of monitoring in complicated and uncomplicated diabetes mellitus cases was discussed. While diabetes mellitus is relatively easy to diagnose, getting the disease under control is often not so straight forward. The session, entitled “Updated Strategies for Monitoring Diabetes and Troubleshooting Your Difficult Diabetics”, was presented by Dr. Jessica Pritchard who is a clinical assistant professor of small animal internal medicine at the University of Wisconsin-Madison.
Numbers of cases of diabetes mellitus are increasing in both cats and dogs. In 2016, Banfield’s State of Pet Health Report showed an increase of 80% in dogs and 18% in cats over a 10-year period. Management of diabetic pets is multi-modal and includes regular monitoring and adjustments of insulin, client education and encouragement of compliance, and management of diet and lifestyle. Confounding factors often include the presence of other disease processes, owner compliance, dietary habits and lifestyle changes.
References for managing diabetes mellitus include the American Animal Hospital Association’s (AAHA) 2018 Diabetes Management Guidelines for Dogs and Cats and the American Association of Feline Practitioner’s (AAFP) 2019 Diabetes Education Toolkit for managing cats. While the AAHA guidelines stress frequent reassessment and monitoring, the AAFP toolkit places importance on client participation in the pet’s treatment and education by the veterinary team with constant dialogue.
Traditionally, monitoring diabetic pets involved a day long hospital stay for a glucose curve. While this is still a valuable tool, it does have drawbacks. Pets in hospital are often stressed which often significantly affects their glucose metabolism. In addition, many pet parents are not fully comfortable leaving their pet for an entire day and feel confused by the process. Recently, more veterinarians have been using flash continuous glucose monitors (FCGMs) to get a better idea of their patients’ blood glucose trends over a longer period of time.
FCGMs, such as the Freestyle Libre, involve attaching a sensor to the skin of the patient and using a reader or smartphone to scan the sensor periodically for glucose measurements. This allows a curve to be done over multiple days without interrupting the patient’s routine or causing stress through hospitalization or blood draws. It also allows the owners to have more involvement in their pet’s care and can be used as an educational tool to help the better understand what is going on with their pet.
The sensors can last up to 2 weeks although some are dislodged sooner by the pet. The owner can scan the sensor periodically and the data will be stored in the web where it can be forward to the veterinarian to view the patient’s trends over the two-week period. FCGMs do have their limitations – namely that they are extremely inaccurate at very low or very high blood glucose levels. The key is to monitor for trends to see if the patient is responding appropriately to the insulin. Dr. Pritchard usually places a sensor every 2 weeks until the pet is regulated and then every 3-6 months. She has the owner’s email her the data weekly to review the trends. Dr. Pritchard also notes that you want to pick your clients for this method of monitoring. Her ideal client for using FCGMs is one that is not overly anxious, is willing to listen to instructions and wants to be involved.
For difficult to control diabetics, Dr. Pritchard advises more in-depth exploration of home life. Her first suggested step is to ask about the insulin including is it shaken or rolled and is it stored correctly. You also want to ask who normally administers he insulin injection and if there have been any changes noted in the color or consistency of the insulin over time.
She also advises to check diet and feeding habits. Check if the owner is free-feeding or if the pet is on set meal times. Ask about treats and between-meal snacks. Diet changes and changes in appetite are also important to discover. If the pet is not eating well, it may be time to change the diet, recheck diagnostics or add in an appetite stimulant.
Also, of importance is to review the patient’s medication history. Often overlooked are topicals and ear and eye drops that contain steroids. Make sure the pet isn’t being exposed to hormone creams used by the owner. If the pet is intact, hormones can be playing a role in insulin resistance. If there are suspect medications, try to find alternatives or discontinue the drugs if they are not necessary. You may need to increase the insulin dose if the medications cannot be discontinued.
Baseline diagnostics for any diabetic include weight, physical exam, CBC, chemistry, triglycerides, urinalysis, urine culture and a thyroid panel. Look for signs of concurrent conditions such as renal disease, urinary tract infection, hypertriglyceridemia, hypothyroidism, hyperadrenocorticism (canine), hypersomatotropism (feline), or pancreatitis and run additional diagnostics as appropriate.
