Management of Diabetic Cats with Long-acting Insulin

Refrigerated multi-dose insulin vials remain sterile through 6 months of use

OBJECTIVES

To evaluate sterility in refrigerated multi-dose insulin vials through 6 months of routine aspiration.

MATERIALS AND METHODS

Twelve vials of insulin, six of insulin glargine U100 (Lantus®, 10 mL multi-dose vial, Sanofi, Bridgewater, NJ) containing the preservative metacresol, and six of protamine zinc insulin U40 (ProZinc®, 10 mL multi-dose vial, Boehringer Ingelheim, Duluth, GA) containing the preservative phenol, were refrigerated and aspirated twice daily for 6 months, using a new insulin syringe each time. Three vials of each insulin type were wiped with a single-use alcohol swab before sampling. Three times weekly, aspirated samples were inoculated in Tryptic Soy Broth enrichment media and incubated for evidence of microbial growth. Positive broth was cultured and speciated. Endpoints were microbial vial contamination (defined as three consecutive positive cultures of the same organism) and completion of the six-month study period.

RESULTS

Microbial contamination was not identified in any vial throughout the study period. A total of 454 aspirated samples were cultured, one of which exhibited non-repeatable growth of Staphylococcus epidermidis. This vial was prematurely lost to breakage after 59 culture samples (29 after the positive growth).

CLINICAL SIGNIFICANCE

Refrigerated phenol- and metacresol-containing multi-dose insulin products carry minimal risk for iatrogenic infection through 6 months of use, regardless of alcohol swab preparation.

Priorities on treatment and monitoring of diabetic cats from the owners' points of view

OBJECTIVES

The aims of this study were to evaluate: owners' perceptions and priorities on the treatment and monitoring of feline diabetes mellitus (DM); the perceived effectiveness of the communication between veterinarians and clients regarding disease management; and the impact DM has on the owners' everyday lives and human-pet bonds.

METHODS

An initial questionnaire, then an adapted second questionnaire, were available to owners of cats with DM on vetprofessionals.com .

RESULTS

A total of 748 questionnaires were completed. At diagnosis, fewer than half of veterinarians discussed how to recognise unstable diabetes (46%) or home blood glucose monitoring (HBGM) (40%). Owners were disappointed that the importance of diet on diabetic remission/stabilisation and HBGM were not discussed. Only 49% of respondents were supervised by a veterinarian/veterinary nurse while first drawing up insulin and injecting their cat. Websites/online forums that owners found themselves were most useful when learning about their cat's diabetes (76% agreed). Over a third of cats (39%) were not fed a 'diabetic' diet but, impressively, 71% of owners used HBGM. Initial concerns about costs, boarding, the effect on their daily life and potential negative impact on the human-pet bond reduced significantly after initiating treatment (P <0.0001).

CONCLUSIONS AND RELEVANCE

Caring for a diabetic cat requires significant owner commitment, plus support by the veterinary team for the owner and their cat. It is difficult to discuss all aspects of this complex disease with the owner in a single consultation; hence, it is important to involve the entire veterinary team in owner education and provide owners with informative material (eg, useful websites, printouts). Understanding owners' priorities, fears, and which monitoring methods have helped others, is paramount to achieve owner compliance and satisfaction, and so improve the health and welfare of diabetic cats. This study provides useful information on the management of feline DM, which can be instrumental in educating future owners.

Basal glucosuria in cats

Objective of this study was to demonstrate the ubiquitous presence of glucose in urine of euglycemic cats by a highly sensitive glucose assay. The local electronic database was searched for results of quantitative urine glucose measurements in cats. A total of 325 feline urine glucose measurements were identified, of which 303 (93%) had been submitted by one of the co-authors working in a near-by small animal practice. After the exclusion of patients with kidney disease (n = 60), hyperthyroidism (n = 15), diabetes mellitus (n = 11), multiple diseases (n = 9) or steroid treatment (n = 3), as well as serial measurements (n = 87) and outliers (n = 8), the final study population consisted of 132 cats. Urine creatinine concentration was unavailable in five patients. Whereas all but one cat had glucose concentrations above the detection limit of the assay (0.11 mmol/L, Gluco-quant Enzyme Kit/Roche Diagnostics), no positive glucose dipstick test result (Combur 9-Test, Roche Diagnostics) was observed. The median (range) of urinary glucose concentration and the glucose-to-creatinine ratio (UGCR) was 0.389 (<0.11-1.665) mmol/L and 0.0258 (0.007-0.517) respectively. The UGCR was not affected by age, gender, breed or leukocyturia, whereas cats with hematuria had slightly higher values. Data show that so-called "basal glucosuria" is present in the majority of cats and by no means diagnostic for diabetes mellitus or renal glucosuria. This has to be considered when using bio-analytical methods with a low limit of quantification.

Managing feline diabetes: current perspectives

Diabetes mellitus is a common endocrine disease in cats. While type 2 diabetes is the most common form seen in cats, other underlying causes may contribute to insulin resistance. Guidelines for diagnosis vary and often do not take into account prediabetic cats. The goals of treatment are to maximize the chance of remission, while minimizing the risks of hypoglycemia. This article presents a further overview of current treatment and monitoring recommendations for diabetic cats.

2018 AAHA Diabetes Management Guidelines for Dogs and Cats*

Diabetes mellitus (DM) is a common disease encountered in canine and feline medicine. The 2018 AAHA Diabetes Management Guidelines for Dogs and Cats revise and update earlier guidelines published in 2010. The 2018 guidelines retain much of the information in the earlier guidelines that continues to be applicable in clinical practice, along with new information that represents current expert opinion on controlling DM. An essential aspect of successful DM management is to ensure that the owner of a diabetic dog or cat is capable of administering insulin, recognizing the clinical signs of inadequately managed DM, and monitoring blood glucose levels at home, although this is ideal but not mandatory; all topics that are reviewed in the guidelines. Insulin therapy is the mainstay of treatment for clinical DM. The guidelines provide recommendations for using each insulin formulation currently available for use in dogs and cats, the choice of which is generally based on efficacy and duration of effect in the respective species. Also discussed are non-insulin therapeutic medications and dietary management. These treatment modalities, along with insulin therapy, give the practitioner an assortment of options for decreasing the clinical signs of DM while avoiding hypoglycemia, the two conditions that represent the definition of a controlled diabetic. The guidelines review identifying and monitoring patients at risk for developing DM, which are important for avoiding unnecessary insulin therapy in patients with transient hyperglycemia or mildly elevated blood glucose.

An individual approach to feline diabetes care: a case report and literature review

Background

Achieving insulin independence is emerging as a realistic therapeutic goal in the management of feline diabetes mellitus.

Case presentation

The management of an 11-year-old spayed female Burmese cat presenting with diabetes mellitus after corticosteroid administration is described. Remission was achieved after the frequency of insulin administration was increased to four times a day, and supported by intensive home blood glucose monitoring and a high protein, low carbohydrate diet.

Conclusion

Owners are important collaborators in feline diabetes care and, with intensive home monitoring, more frequent insulin treatment may lead to remission without hypoglycemia. More frequent insulin injections than recommended in the literature may be necessary to achieve glycemic control and used as an alternative to a longer-acting insulin.

Update on insulin treatment for dogs and cats: insulin dosing pens and more

Insulin therapy is still the primary therapy for all diabetic dogs and cats. Several insulin options are available for each species, including veterinary registered products and human insulin preparations. The insulin chosen depends on the individual patient’s requirements. Intermediate-acting insulin is usually the first choice for dogs, and longer-acting insulin is the first choice for cats. Once the insulin type is chosen, the best method of insulin administration should be considered. Traditionally, insulin vials and syringes have been used, but insulin pen devices have recently entered the veterinary market. Pens have different handling requirements when compared with standard insulin vials including: storage out of the refrigerator for some insulin preparations once pen cartridges are in use; priming of the pen to ensure a full dose of insulin is administered; and holding the pen device in place for several seconds during the injection. Many different types of pen devices are available, with features such as half-unit dosing, large dials for visually impaired people, and memory that can display the last time and dose of insulin administered. Insulin pens come in both reusable and disposable options. Pens have several benefits over syringes, including improved dose accuracy, especially for low insulin doses.

ISFM consensus guidelines on the practical management of diabetes mellitus in cats

PRACTICAL RELEVANCE

Diabetes mellitus (DM) is a common endocrinopathy in cats that appears to be increasing in prevalence. The prognosis for affected cats can be good when the disease is well managed, but clinical management presents challenges, both for the veterinary team and for the owner. These ISFM Guidelines have been developed by an independent, international expert panel of clinicians and academics to provide practical advice on the management of routine (uncomplicated) diabetic cats.

CLINICAL CHALLENGES

Although the diagnosis of diabetes is usually straightforward, optimal management can be challenging. Clinical goals should be to limit or eliminate clinical signs of the disease using a treatment regimen suitable for the owner, and to avoid insulin-induced hypoglycaemia or other complications. Optimising bodyweight, feeding an appropriate diet and using a longer acting insulin preparation (eg, protamine zinc insulin, insulin glargine or insulin detemir) are all factors that are likely to result in improved glycaemic control in the majority of cats. There is also some evidence that improved glycaemic control and reversal of glucose toxicity may promote the chances of diabetic remission. Owner considerations and owner involvement are an important aspect of management. Provided adequate support is given, and owners are able to take an active role in monitoring blood glucose concentrations in the home environment, glycaemic control may be improved. Monitoring of other parameters is also vitally important in assessing the response to insulin. Insulin adjustments should always be made cautiously and not too frequently--unless hypoglycaemia is encountered.

EVIDENCE BASE

The Panel has produced these Guidelines after careful review of the existing literature and of the quality of the published studies. They represent a consensus view on practical management of cats with DM based on available clinical data and experience. However, in many areas, substantial data are lacking and there is a need for better studies in the future to help inform and refine recommendations for the clinical management of this common disease.

Systematic review of feline diabetic remission: separating fact from opinion

It is increasingly recognised that diabetic remission is possible in the cat. This systematic review, following Cochrane Collaboration (CC) guidelines, critically appraises the level of evidence on factors influencing remission rate and factors predicting remission. A systematic online, bibliographic search and reference list examination was conducted. A level of evidence was assigned to each identified article by five internists using the Newcastle-Ottawa Scale for follow-up, cohort, case-series and case-control studies, the CC's risk of bias tool for trials and the Cochrane Effective Practice and Organisation of Care Group risk of bias criteria for before and after trials. Twenty-two studies were included in the review, assessing influence of pharmaceutical intervention (n = 14) and diet (n = 4), as well as diagnostic tests (n = 9) and feline patient characteristics (n = 5) as predictors of remission. The current level of evidence was found to be moderate to poor. Common sources of bias included lack of randomisation and blinding among trials, and many studies were affected by small sample size. Failure to provide criteria for the diagnosis of diabetes, or diabetic remission, and poor control of confounding factors were frequent causes of poor study design. Addressing these factors would significantly strengthen future research and ultimately allow meta-analyses to provide an excellent level of evidence. No single factor predicts remission and successful remission has been documented with a variety of insulin types and protocols. Dietary carbohydrate reduction might be beneficial, but requires further study. A lack of well-designed trials prevents reliable remission rate comparison. Factors associated with remission resemble those in human medicine and support the hypothesis that reversal of glucotoxicity is a major underlying mechanism for feline diabetic remission.