Diabetic remission in cats: Does it really exist and how do we achieve it?
In his presentation “Diabetic remission in cats,” at the American College of Veterinary Internal Medicine (ACVIM) Small Animal Internal Medicine Endocrinology Course, Stijn Niessen, DVM, PhD, DECVIM, PGCVetEd, FHEA, MRCVS, discussed what we know and what we still have to learn about diabetic remission in cats based on the available veterinary literature. Not only is there no consensus on what exactly constitutes diabetic remission, but we are not entirely clear on what the best protocol is to get to that point. Niessen noted that clinicians also do not have a clear way of predicting which cats are more likely to go into remission.
Before we decide what the ideal protocol to achieve diabetic remission would entail, Niessen says we need to understand the underlying pathophysiology involved in the development of feline diabetes. We know that regardless of what is causing beta cell dysfunction or death, ongoing hyperglycemia and perhaps hyperlipidemia need to be addressed. For this reason timely intervention is key to increasing the chances of remission, and, even if complete remission is not achieved, patients with better glycemic control will ultimately have improved beta cell function.
What the literature says
Niessen discussed a systematic review of the literature that was published by his team in 2014.1 About 20 studies on the topic of diabetic remission in cats have been published in the last 15 years. He notes, however, that specific conclusions are difficult to evaluate given the heterogeneity of the studies (e.g. nonstandardized definition of remission, nonexclusion of patients with concurrent conditions such as pancreatitis or corticosteroid exposure or lack of standardized diets). Using Cochrane Collaboration guidelines, which assess the strength of the scientific evidence (1 = strong evidence without bias, 4 = weak evidence with significant bias), most veterinary articles on this topic score a level 4, with some reaching level 3. Niessen says this is an important distinction to consider before making decisions that will impact daily clinical practice.
What can we do with the evidence that we have?
Niessen pointed out that the literature indicates diabetic remission appears to happen most often in cats that become diabetic later in life and that newly diagnosed cats have a better chance at remission. Alternatively, cats that have evidence of a peripheral neuropathy at the time of diagnosis are less likely to achieve remission.
The analysis also found one level 3 study that indicated a low-carbohydrate diet (< 12% metabolizable energy) may be the most beneficial for increasing the odds of remission. However, Niessen says more studies are needed to assess the impact of varying protein and carbohydrate combinations for diabetic cats. The diet choice will also need to reflect concurrent medical conditions such as renal disease, where a low-carbohydrate/high-protein diet may not be suitable.
When evaluating which insulin type is most likely to increase the chances of remission, Niessen pointed out that, while glargine has been the most studied, other insulin types have also been shown to achieve similar remission rates. In addition, some of the studies evaluating glargine have only been conducted in small numbers of cats and without comparison to a control group. While he acknowledged that further studies are needed, Niessen suggested that glargine or another long-acting insulin such as PZI or insulin detemir will likely increase the chances of achieving remission in diabetic cats.
When monitoring glycemic control in these patients, Niessen discussed studies in which intense monitoring (ear pricks multiple times a day) achieved similar remission rates as other studies that used a more relaxed approach. There are currently no randomized, controlled trials available that define what the best monitoring approach is for these patients. But he did suggest that home monitoring should be considered for our feline patients if owner circumstances allow.
1. Gostelow R, Forcada Y, Graves T, et al. Systematic review of feline diabetic remission: separating fact from opinion. Vet J 2014;202(2):208-221.