Predictors of clinical remission in cats with diabetes mellitus

Uncommon dermatologic manifestation (paronychia) in a cat with diabetes mellitus

A 3.5-year-old male intact domestic short hair cat presented for a chronic wound and crusts over the claw and claw folds over several months. The cat was diagnosed with diabetes mellitus based on the presence of persistent hyperglycemia, glucosuria, and compatible clinical signs which consist of polyuria, polydipsia, polyphagia, and weight loss. Glipizide (Glucotrol XL, Pfizer, Indonesia) 2.5 mg orally twice daily was prescribed. By the seventeenth day, the patient's claws and skin around the paw had normalized and the abnormal claw sloughed off, revealing a normal claw underneath. Blood glucose, urinalysis and serum fructosamine were also normalized by the thirtieth day. The patient underwent diabetic remission, and the skin and claw lesions have remained in remission and not recurred since the treatment of the diabetes mellitus. This is the first report of a diabetic cat with dermatologic changes to the skin and claw regions. As the diabetes mellitus went into clinical remission, so too did the dermatologic manifestations, even without any specific dermatologic treatment.

Frequency of diabetic remission, predictors of remission and survival in cats using a low-cost, moderate-intensity, home-monitoring protocol and twice-daily glargine

OBJECTIVES

The aim of the present study was to retrospectively assess remission rates and survival in diabetic cats managed using a moderate-intensity, low-cost protocol of home blood glucose measurements and insulin adjustment by clients of a cat-only practice, and to determine if predictors of remission, relapse or survival could be identified.

METHODS

The records of a cat-only practice were used to identify 174 cats with newly diagnosed diabetes managed using only pre-insulin home blood glucose measurements for insulin dose adjustments based on a protocol provided to clients aimed at maintaining pre-insulin blood glucose in the range of 6.5-11.9 mmol/l (117-214 mg/dl). Cats were excluded for the following reasons: insufficient follow-up in the records; a lack of owner compliance was recorded; they were receiving ongoing corticosteroids for the management of other conditions; they were euthanased at the time of diagnosis; or they were diagnosed with acromegaly or hyperadrenocorticism.

RESULTS

Using only pre-insulin blood glucose measurements at home to adjust the insulin dose to maintain glucose in the range of 6.5-11.9 mmol/l, 47% of cats achieved remission, but 40% of those cats relapsed. A minority (16%) of cats were hospitalised for hypoglycaemia. The survival time was significantly longer in cats in remission and Burmese cats.

CONCLUSIONS AND RELEVANCE

The cost and time burden of treating diabetic cats may cause some clients to choose euthanasia over treatment. While the highest rates of diabetic remission have been reported in studies of newly diagnosed cats treated with intensive long-acting insulin protocols and low carbohydrate diets, these protocols may not be suitable for all clients. Nearly 50% of cats with newly diagnosed diabetes achieved remission with this low-cost, moderate-intensity, insulin dosing protocol. As remission was significantly associated with survival time, discussing factors in treatment to optimise remission is important, but it is also important to offer clients a spectrum of options. No cats that started treatment in this study were euthanased because the owner did not wish to continue the diabetes treatment.

Spontaneous remission and relapse of diabetes mellitus in a male dog

An 8-year-old male neutered Miniature Schnauzer was diagnosed with diabetes mellitus based on fasting hyperglycemia and glucosuria after a 2-week history of polydipsia and periuria, in line with the Agreeing Language in Veterinary Endocrinology consensus definition. Treatment of insulin and dietary management was initiated. The insulin dose was gradually reduced and eventually discontinued over the next year based on spot blood glucose concentrations that revealed euglycemia or hypoglycemia. After discontinuation, the dog remained free of clinical signs for 1 year until it was again presented for polyuria/polydipsia with fasting hyperglycemia and glucosuria. Insulin therapy was resumed and continued for the remainder of the dog's life. Although diabetic remission often occurs in cats and humans, the presumed etiopathogenesis of pancreatic beta cell loss makes remission rare in dogs, except for cases occurring with diestrus or pregnancy. This case demonstrates that diabetic remission is possible in dogs, even in cases without an identifiable reversible trigger.

Pathophysiology of Prediabetes, Diabetes, and Diabetic Remission in Cats

Diabetes mellitus (DM) has a heterogenous cause, and the exact pathogenesis differs between patients. Most diabetic cats have a cause similar to human type 2 DM but, in some, DM is associated with underlying conditions, such as hypersomatotropism, hyperadrenocorticism, or administration of diabetogenic drugs. Predisposing factors for feline DM include obesity, reduced physical activity, male sex, and increasing age. Gluco(lipo)toxicity and genetic predisposition also likely play roles in pathogenesis. Prediabetes cannot be accurately diagnosed in cats at the current time. Diabetic cats can enter remission, but relapses are common, as these cats might have ongoing, abnormal glucose homeostasis.

Survival, remission, and quality of life in diabetic cats

BACKGROUND

Remission is documented in a substantial proportion of cats with diabetes. The effects of diabetes mellitus (DM) on the lives of cats and their owners should be considered when evaluating treatment success.

OBJECTIVES

To study outcome in cats with DM and the impact DM has on the life situation of cat and owner.

ANIMALS

Domestic and pedigree cats with a diagnosis of DM (n = 477) insured by a Swedish insurance company during 2009 to 2013.

METHODS

Retrospective cross-sectional study. A questionnaire was sent to 1369 owners of cats diagnosed with DM. The questions concerned the cat, treatment, owner perceptions of the disease and treatment and disease outcome. Data were analyzed using multiple linear and logistic regression, with outcomes set as survival for more than 4 weeks after diagnosis, survival time, achieving remission, remission without relapse and quality of life (QoL) for the cat.

RESULTS

The response rate was 35%, leaving 477 questionnaires for analysis. The remission rate among treated cats was 29% (118/405). Feeding a commercially available wet diet was associated with both remission (OR 3.16, 95% confidence interval 1.27-8.12) and remission without relapse (OR 14.8, 95% confidence interval 2.25-153.8). Remission was associated with a better QoL for the cat.

CONCLUSIONS AND CLINICAL IMPORTANCE

The association between feeding a commercially available wet diet and remission is important and strengthens the role of diet in treatment of DM in cats. Linking remission and a better QoL for the cat emphasizes remission as a goal in disease management.

Influence of high-protein and high-carbohydrate diets on serum lipid and fructosamine concentrations in healthy cats

OBJECTIVES

The aim of this study was to determine whether high-protein and high-carbohydrate diets exert differential effects on serum cholesterol, triglyceride and fructosamine concentrations in healthy cats.

METHODS

A randomised, crossover diet trial was performed in 35 healthy shelter cats. Following baseline health assessments, cats were randomised into groups receiving either a high-protein or high-carbohydrate diet for 4 weeks. The cats were then fed a washout diet for 4 weeks before being transitioned to whichever of the two studied diets they had not yet received. Fasting serum cholesterol, triglyceride and fructosamine concentrations were determined at the end of each 4-week diet period.

RESULTS

Cats on the high-carbohydrate diet had significantly lower serum cholesterol (P <0.001) concentrations compared with baseline measurements. Cats on the high-protein diet had significantly higher serum cholesterol (P <0.001) and triglyceride (P <0.001) concentrations, yet lower fructosamine (P <0.001) concentrations compared with baseline measurements. In contrast, overweight cats (body condition score [BCS] >5) had lower cholesterol (P = 0.007) and triglyceride (P = 0.032) concentrations on the high-protein diet than cats within other BCS groups.

CONCLUSIONS AND RELEVANCE

Diets higher in protein and lower in carbohydrates appear beneficial for short-term glucose control in healthy cats. A high-protein diet was associated with significantly elevated cholesterol and triglyceride concentrations in healthy cats, even though the increase was significantly less pronounced in cats with a BCS >5. This finding suggests that overweight cats process high-protein diets, cholesterol and triglycerides differently than leaner cats.

Evaluation of the FreeStyle Libre, a flash glucose monitoring system, in client-owned cats with diabetes mellitus

Objectives

Home blood glucose monitoring using a portable blood glucose meter is important in the management of feline diabetes mellitus, but taking blood samples may be stressful for owners and cats. A flash glucose monitoring system measuring interstitial glucose, such as the FreeStyle Libre, overcomes some of these drawbacks. The aim of this study was to evaluate the practical use and analytical and clinical accuracy of the FreeStyle Libre in 41 client-owned diabetic cats.

Methods

In this prospective study, interstitial glucose concentrations were measured with the FreeStyle Libre and compared with blood glucose concentrations measured with a portable blood glucose meter (AlphaTRAK) on days 1, 7 or 8 and 14 after application of the device. Cat behaviour during application, location, skin reaction at the attachment site and owner satisfaction were assessed. Accuracy was determined by fulfilment of ISO 15197:2013 criteria, including Bland–Altman plotting and error grid analysis.

Results

Placing the device was easy, with 70% of cats showing no reaction. Most sensors were placed on the thoracic wall. Skin reactions at the attachment site were not present or mild in almost all cats. Owners were very satisfied with the use of the FreeStyle Libre. Median functional life of the sensor was 10 days (range 1–14). Good correlation was found between interstitial and blood glucose measurements (rho[r] = 0.88, P <0.0001). Fifty-three percent of interstitial glucose concentrations were within a maximum deviation of 15% from blood glucose concentrations and 92.7% were within the safe risk zones 0 and 1 of the surveillance error grid.

Conclusions and relevance

The flash glucose monitoring system was easy to use and owners of diabetic cats were satisfied with its use. Although the device did not completely fulfil ISO requirements, it is sufficiently accurate for glucose monitoring in diabetic cats.

Insulin glargine 300 U/ml for the treatment of feline diabetes mellitus

OBJECTIVES

The study aimed to evaluate the efficacy and safety of insulin glargine 300 U/ml (IGla-U300) in cats with variable duration of diabetes mellitus (DM).

METHODS

Thirteen client-owned cats with DM completed a prospective clinical trial. Four cats were highly suspected of hypersomatotropism and excluded from the insulin efficacy evaluation. All cats were treated with IGla-U300 SC at a starting dosage of 0.5 U/kg q12h and fed with a low carbohydrate diet. Cats were monitored for 8 weeks with a once-weekly at-home 16 h blood glucose curve (BGC) and a questionnaire evaluating the presence of DM-related clinical signs. In-clinic evaluations, including serum fructosamine measurement, were scheduled within 3 days of the first, third, sixth and eighth BGC. Glycemic variability was assessed by calculating the SD of each BGC.

RESULTS

Excluding four cats suspected of hypersomatotropism, at the time of the eighth BGC, improved or absent polyuria, polydipsia, polyphagia, weight loss, lethargy and improved or normal general demeanor were reported in 8/9 (88%), 8/9 (88%), 7/9 (77%), 7/9 (77%), 7/9 (77%) and 8/9 (88%) cats, respectively. Two cats achieved remission after 29 and 53 days. Another two cats went into remission after the end of the study (days 82 and 96). All cats that achieved remission were newly diagnosed diabetics. Median (range) serum fructosamine concentration significantly decreased when comparing the time of enrollment (604 [457-683] µmol/l) with the eighth week of treatment (366 [220-738] µmol/l) (P = 0.02). In all 13 cats, biochemical hypoglycemia (blood glucose <60 mg/dl; <3.3 mmol/l) was detected in 13/104 (12.5%) BGCs, while clinical signs suggesting hypoglycemic episodes were not reported. Glycemic variability was significantly lower at the fifth BGC when comparing cats that achieved remission with cats that did not achieve remission (P = 0.02).

CONCLUSIONS AND RELEVANCE

IGla-U300 seems effective and safe for the treatment of feline diabetes, but more long- term and comparative clinical trials are needed.

Mapping of Diabetes Susceptibility Loci in a Domestic Cat Breed with an Unusually High Incidence of Diabetes Mellitus

Genetic variants that are associated with susceptibility to type 2 diabetes (T2D) are important for identification of individuals at risk and can provide insights into the molecular basis of disease. Analysis of T2D in domestic animals provides both the opportunity to improve veterinary management and breeding programs as well as to identify novel T2D risk genes. Australian-bred Burmese (ABB) cats have a 4-fold increased incidence of type 2 diabetes (T2D) compared to Burmese cats bred in the United States. This is likely attributable to a genetic founder effect. We investigated this by performing a genome-wide association scan on ABB cats. Four SNPs were associated with the ABB T2D phenotype with p values <0.005. All exons and splice junctions of candidate genes near significant single-nucleotide polymorphisms (SNPs) were sequenced, including the genes DGKG, IFG2BP2, SLC8A1, E2F6, ETV5, TRA2B and LIPH. Six candidate polymorphisms were followed up in a larger cohort of ABB cats with or without T2D and also in Burmese cats bred in America, which exhibit low T2D incidence. The original SNPs were confirmed in this cohort as associated with the T2D phenotype, although no novel coding SNPs in any of the seven candidate genes showed association with T2D. The identification of genetic markers associated with T2D susceptibility in ABB cats will enable preventative health strategies and guide breeding programs to reduce the prevalence of T2D in these cats.

Understanding the Nutritional Needs of Healthy Cats and Those with Diet-Sensitive Conditions

Diets for cats must provide complete nutrition and meet the needs of the individual patient. There is no single diet that is perfect for all cats, and veterinarians must consider the needs of the cat as well as the preferences of the owners when making dietary recommendations. This article focuses on the interface between animal factors and nutritional needs in cats and is divided into 3 sections. Section 1 addresses the dietary needs of healthy cats, including differences among life stages. Section 2 addresses common myths regarding feline nutrition. Section 3 addresses common nutrient-sensitive conditions in cats, including sarcopenia of aging.

Metabolic Profiling of Diabetic Cats in Remission

Background: The majority of diabetic cats in remission have abnormal glucose tolerance, and approximately one third relapse within 1 year. Greater understanding of the metabolic characteristics of diabetic cats in remission, and predictors of relapse is required to effectively monitor and manage these cats.

Objectives: To identify and compare differences in plasma metabolites between diabetic cats in remission and healthy control cats using a metabolomics approach. Secondly, to assess whether identified metabolites are predictors of diabetic relapse.

Animals: Twenty cats in diabetic remission for a median of 101 days, and 22 healthy matched control cats.

Methods: Cats were admitted to a clinic, and casual blood glucose was recorded. After a 24 h fast, blood glucose concentration was measured, then a blood sample was taken for metabolomic (GCMS and LCMS) analyses. Three hours later, a simplified intravenous glucose tolerance test (1 g glucose/kg) was performed. Cats were monitored for diabetes relapse for at least 9 months (270 days) after baseline testing.

Results: Most cats in remission continued to display impaired glucose tolerance. Concentrations of 16 identified metabolites differed (P ≤ 0.05) between remission and control cats: 10 amino acids and stearic acid (all lower in remission cats), and glucose, glycine, xylitol, urea and carnitine (all higher in remission cats). Moderately close correlations were found between these 16 metabolites and variables assessing glycaemic responses (most |r| = 0.31 to 0.69). Five cats in remission relapsed during the study period. No metabolite was identified as a predictor of relapse.

Conclusion and clinical importance: This study shows that cats in diabetic remission have abnormal metabolism.

Oxidative status of erythrocytes, hyperglycemia, and hyperlipidemia in diabetic cats

Background

Erythrocytes of diabetic cats have decreased superoxide dismutase activity, possibly indicative of oxidative stress.

Hypothesis

Erythrocytes of diabetic cats undergo oxidative stress, which is caused by hyperglycemia and hyperlipidemia, and improves with treatment.

Animals

Twenty‐seven client‐owned cats with diabetes mellitus, 11 matched healthy cats, and 21 purpose‐bred healthy cats.

Methods

Prospective study. Advanced oxidized protein products, carbonyls (protein oxidation by‐products), and thiols (antioxidants) were quantified in erythrocyte membrane, thiobarbituric acid reactive substances (TBAR, lipid peroxidation by‐products), and thiols in erythrocyte cytoplasm of all cats. Comparison were performed between diabetic and matched healthy cats, between diabetic cats achieving remission or not, and among purpose‐bred cats after 10 days of hyperglycemia (n = 5) or hyperlipidemia (n = 6) versus controls treated with saline (n = 5) or untreated (n = 5).

Results

Compared with controls, erythrocytes of diabetic cats initially had higher median membrane carbonyls (4.6 nmol/mg total protein [range: 0.1‐37.7] versus 0.7 [0.1‐4.7], P < .001) and lower cytoplasmic TBAR (1.9 nmol/mg [0.5‐2.4] versus 2.4 [1.4‐3.5] P < .001), and thiols (419 nmol/mg [165‐621] versus 633 [353‐824], P < 0.001). After 12‐16 weeks of treatment in diabetic cats, carbonyls decreased by 13% (P < .001), but remained higher (P < .001) and TBAR and thiols lower (P = .02, P < .001) than those in controls. No differences were observed between diabetic cats achieving remission or not, and among purpose‐bred cats.

Conclusions and Clinical Importance

Diabetes mellitus is associated with increased protein oxidation and reduced antioxidant defenses, which persist during treatment and remission, although mild improvement in protein oxidation occurs. Short‐term hyperglycemia or hyperlipidemia does not cause oxidative stress. The reason for decreased TBAR remains unknown.

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.

Glucose concentrations after insulin-induced hypoglycemia and glycemic variability in healthy and diabetic cats

Background

Little information is available about posthypoglycemic hyperglycemia (PHH) in diabetic cats, and a causal link between hypoglycemia and subsequent hyperglycemia is not clear. Fluctuations in blood glucose concentrations might only represent high glycemic variability.

Hypothesis

Insulin induces PHH in healthy cats, and PHH is associated with poorly regulated diabetes and increased glycemic variability in diabetic cats.

Animals

Six healthy cats, 133 diabetic cats.

Methods

Insulin (protamine‐zinc and degludec; 0.1‐0.3 IU/kg) administered to healthy cats. Blood glucose curves were generated with portable glucose meter to determine the percentage of curves with PHH. Data from insulin‐treated diabetic cats with blood glucose curves showing hypoglycemia included data of cats with and without PHH. Post‐hypoglycemic hyperglycemia was defined as blood glucose concentrations <4 mmol/L followed by blood glucose concentrations >15 mmol/L within 12 hours. Glycemic variability was calculated as the standard deviation of the blood glucose concentrations.

Results

In healthy cats, all insulin doses caused hypoglycemia but PHH was not observed; glycemic variability did not differ between insulin preparations. Among diabetic cats with hypoglycemia, 33 (25%) had PHH. Compared with cats without PHH, their daily insulin dose was higher (1.09 ± 0.55 versus 0.65 ± 0.56 IU/kg; P < .001), serum fructosamine concentration was higher (565 ± 113 versus 430 ± 112 µmol/L; P < .001), remission was less frequent (10% versus 56%; P < .001), and glycemic variability was larger (8.1 ± 2.4 mmol/L versus 2.9 ± 2.2 mmol/L; P < .001).

Conclusions and Clinical Importance

Insulin‐induced hypoglycemia did not cause PHH in healthy cats but it occurred in 25% of diabetic cats with hypoglycemia, particularly when diabetes was poorly controlled. Glycemic variability was increased in cats with PHH.

Differential circulating concentrations of adipokines, glucagon and adropin in a clinical population of lean, overweight and diabetic cats

BACKGROUND

Dyslipidemia, dysregulated adipokine secretion and alteration in glucagon and adropin concentrations are important obesity-related factors in the pathophysiology of human Type 2 diabetes; however, their roles in the pathophysiology of feline diabetes mellitus are relatively unknown. Here, we determined the concentrations of circulating leptin, adiponectin, pro-inflammatory cytokines, glucagon, adropin, triglycerides, and cholesterol, in non-diabetic lean and overweight cats and newly diagnosed diabetic cats. Client-owned cats were recruited and assigned into 3 study groups: lean, overweight and diabetic. Fasting blood samples were analyzed in lean, overweight and diabetic cats at baseline and 4 weeks after consumption of high protein/low carbohydrate standardized diet.

RESULTS

Serum concentrations of triglycerides were greater in diabetics at baseline and were increased in both diabetic and overweight cats at 4 weeks. Plasma leptin concentrations were greater in diabetic and overweight at baseline and 4 weeks, whereas adiponectin was lower in diabetics compared to lean and overweight cats at baseline and 4 weeks. Diabetics had greater baseline plasma glucagon concentrations compared to lean, lower adropin than overweight at 4 weeks, and lower IL-12 concentrations at 4 weeks than baseline.

CONCLUSIONS

Our results suggest that feline obesity and diabetes mellitus are characterized by hypertriglyceridemia and hyperleptinemia; however, diabetic cats have significantly lower adiponectin and adropin compared to overweight cats. Thus, despite having similar body condition, overweight and diabetic cats have differential circulating concentrations of adiponectin and adropin.

What's in a Name? Classification of Diabetes Mellitus in Veterinary Medicine and Why It Matters

Diabetes Mellitus (DM) is a syndrome caused by various etiologies. The clinical manifestations of DM are not indicative of the cause of the disease, but might be indicative of the stage and severity of the disease process. Accurately diagnosing and classifying diabetic dogs and cats by the underlying disease process is essential for current and future studies on early detection, prevention, and treatment of underlying disease. Here, we review the current etiology-based classification of DM and definitions of DM types in human medicine and discuss key points on the pathogenesis of each DM type and prediabetes. We then review current evidence for application of this etiology-based classification scheme in dogs and cats. In dogs, we emphasize the lack of consistent evidence for autoimmune DM (Type 1) and the possible importance of other DM types such as DM associated with exocrine pancreatic disease. While most dogs are first examined because of DM in an insulin-dependent state, early and accurate diagnosis of the underlying disease process could change the long-term outcome and allow some degree of insulin independence. In cats, we review the appropriateness of using the umbrella term of Type 2 DM and differentiating it from DM secondary to other endocrine disease like hypersomatotropism. This differentiation could have crucial implications on treatment and prognosis. We also discuss the challenges in defining and diagnosing prediabetes in cats.

Effect of the Glucagon-like Peptide-1 Analogue Exenatide Extended Release in Cats with Newly Diagnosed Diabetes Mellitus

Background

Exenatide extended release (ER) is a glucagon‐like peptide‐1 analogue that increases insulin secretion, inhibits glucagon secretion and induces satiation in humans with type 2 diabetes mellitus. The use of exenatide ER is safe and stimulates insulin secretion in healthy cats.

Objectives

The objective of this study is to assess the safety of exenatide ER and its effect on body weight, remission and metabolic control in newly diagnosed diabetic cats receiving insulin and a low‐carbohydrate diet.

Animals

Thirty client‐owned cats.

Methods

Prospective placebo‐controlled clinical trial. Cats were treated with exenatide ER or 0.9% saline, administered SC, once weekly. Both groups received insulin glargine and a low‐carbohydrate diet. Exenatide ER was administered for 16 weeks, or in cats that achieved remission it was given for 4 weeks after discontinuing insulin treatment. Nonparametric tests were used for statistical analysis.

Results

Cats in the exenatide ER and placebo groups had transient adverse signs including decreased appetite (60% vs. 20%, respectively, P = .06) and vomiting (53% vs. 40%, respectively, P = .715). Body weight increased significantly in the placebo group (P = .002), but not in cats receiving exenatide ER. Cats on exenatide ER achieved remission or good metabolic control in 40% or 89%, respectively, whereas in control cats percentages were 20% or 58% (P = .427 and P = .178, respectively).

Conclusion and clinical importance

Exenatide ER is safe in diabetic cats and does not result in weight gain. Our pilot study suggests that, should there be an additional clinically relevant beneficial effect of exenatide ER in insulin‐treated cats on rate of remission and good metabolic control, it would likely approximate 20% and 30%, respectively.

Longitudinal evaluation of serum pancreatic enzymes and ultrasonographic findings in diabetic cats without clinically relevant pancreatitis at diagnosis

Background

Cats with diabetes mellitus can have subclinical pancreatitis but prospective studies to confirm this are lacking. Metabolic control of diabetic cats with pancreatitis is difficult.

Hypothesis

Subclinical pancreatitis occurs in diabetic cats at the time diabetes is diagnosed or might develop during the follow‐up period, hampering diabetic remission.

Animals

Thirty cats with newly diagnosed diabetes without clinical signs of pancreatitis on admission.

Methods

Prospective study. On admission and 2 and 6 months later, serum Spec fPL and DGGR‐lipase were measured and the pancreas underwent ultrasonographic examination. Pancreatitis was suspected if serum markers were increased or ≥2 ultrasonographic abnormalities were detected. Cats were treated with insulin glargine and diabetic remission was defined as euglycemia ≥4 weeks after discontinuation of insulin. Nonparametric statistical tests were used for analysis.

Results

Subclinical pancreatitis at the time of diagnosis was suspected in 33, 50, and 31% of cats based on Spec fPL, DGGR‐lipase and ultrasonography, respectively; and in 60% when diagnostic criteria were combined. During the follow‐up period, suspected pancreatitis developed in additional 17–30% cats. Only 1 cat had transient clinical signs compatible with pancreatitis. Seventeen of the 30 cats (57%) achieved remission. Frequency of abnormal Spec fPL and DGGR‐lipase and abnormal ultrasonographic findings did not differ in cats achieving remission and those who did not. Cats achieving remission had significantly lower Spec fPL at 2 months (P < .001).

Conclusions and Clinical Importance

Based on laboratory and ultrasonographic measurements, many cats with diabetes might have pancreatitis, although without clinical signs. Cats with high Spec fPL might have a reduced chance of diabetic remission; however, this topic needs further studies in large cohorts of diabetic cats.

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.

Glycemic status and predictors of relapse for diabetic cats in remission

Background

It is unknown if diabetic cats in remission have persistent abnormalities of glucose metabolism and should be considered prediabetic, or have normal glucose tolerance.

Objective

To characterize glycemic status of diabetic cats in remission and to determine predictors of relapse.

Animals

A total of 21 cats in diabetic remission and 28 healthy control cats.

Methods

At a median of 107 days after remission, screening blood glucose concentration was measured on entry to the clinic. After a 24‐hour fast in hospital, fasting blood glucose, fructosamine and feline pancreatic lipase concentrations were measured, and 3 hours later, a simplified IV glucose tolerance test (1 g glucose/kg) performed. Twenty cats were monitored for relapse for at least 9 months.

Results

Of the 21 cats in remission, 19% (4/21) had impaired fasting glucose concentration and 76% (16/21) had impaired glucose tolerance. Of cats followed up for 9 months after testing, 30% (6/20) had relapsed and required insulin treatment. Fasting blood glucose concentration ≥7.5 mmol/L (≥135 mg/dL) (odds ratio [OR] = 12.8) and severely impaired glucose tolerance (≥5 hours to return to <6.5 mmol/L or <117 mg/dL; OR = 15.2) were significantly associated with relapse. Blood glucose concentration >14 mmol/L; 252 mg/dL at 3 hours was significantly associated with relapse (OR = 10.1).

Conclusion and Clinical Importance

Most cats in diabetic remission have impaired glucose tolerance and a minority have impaired fasting glucose concentration and should be considered prediabetic. More severe glucose intolerance and impaired fasting glucose concentration are predictors of relapse. Ongoing glucose monitoring of diabetic cats in remission is recommended.

Feline diabetes mellitus: clinical use of long-acting glargine and detemir

PRACTICAL RELEVANCE

Diabetes mellitus is a common endocrine disorder in feline practice, affecting approximately 1 in 200 cats. The majority of diabetic cats have type 2 diabetes mellitus, which results from a combination of peripheral insulin resistance and a progressive reduction in insulin production.

CLINICAL CHALLENGES

While usually easy to diagnose, management of diabetes mellitus presents a number of challenges for practitioners and clients alike. Practitioners must decide on diet, insulin type and dose, monitoring method and intensity, and concomitant therapy, which will vary based on individual patient and client needs, and geographic location. Practitioners may also encounter patients with diabetic ketoacidosis or other diabetic complications, and patients with multiple concurrent diseases. Clients may be challenged by the substantial time and financial commitment involved in owning a diabetic cat.

AUDIENCE

Understanding the pathophysiology, optimal treatment protocols and current goals of diabetes management will benefit practitioners managing diabetic cats. This article reviews the most current management plans for feline diabetics. It places particular emphasis on best practice for achieving diabetic remission, which is an attainable goal in the majority of newly diagnosed diabetic cats.

EVIDENCE BASE

The information in this article is drawn from the recent human and veterinary literature, including prospective and retrospective studies. The body of prospective clinical data on the use of newer, long-acting insulins (glargine and especially detemir) in cats is limited, but growing.

Intensive intravenous infusion of insulin in diabetic cats

Background

Remission occurs in 10–50% of cats with diabetes mellitus (DM). It is assumed that intensive treatment improves β‐cell function and increases remission rates.

Hypothesis

Initial intravenous infusion of insulin that achieves tight glycemic control decreases subsequent insulin requirements and increases remission rate in diabetic cats.

Animals

Thirty cats with newly diagnosed DM.

Methods

Prospective study. Cats were randomly assigned to one of 2 groups. Cats in group 1 (n = 15) received intravenous infusion of insulin with the goal of maintaining blood glucose concentrations at 90–180 mg/dL, for 6 days. Cats in group 2 (n = 15) received subcutaneous injections of insulin glargine (cats ≤4 kg: 0.5–1.0 IU, q12h; >4 kg 1.5–2.0 IU, q12h), for 6 days. Thereafter, all cats were treated with subcutaneous injections of insulin glargine and followed up for 6 months. Cats were considered in remission when euglycemia occurred for ≥4 weeks without the administration of insulin. Nonparametric tests were used for statistical analysis.

Results

In groups 1 and 2, remission was achieved in 10/15 and in 7/14 cats (P = .46), and good metabolic control was achieved in 3/5 and in 1/7 cats (P = .22), respectively. Overall, good metabolic control or remission occurred in 13/15 cats of group 1 and in 8/14 cats of group 2. In group 1, the median insulin dosage given during the 6‐month follow‐up was significantly lower than in group 2 (group 1: 0.32 IU/kg/day, group 2: 0.51 IU/kg/day; P = .013).

Conclusions and Clinical Importance

Initial intravenous infusion of insulin for tight glycemic control in cats with DM decreases insulin requirements during the subsequent 6 months.

Effects of pioglitazone on insulin sensitivity and serum lipids in obese cats

Background

Pioglitazone is a thiazolidinedione (TZD) insulin sensitizer approved for use in human type 2 diabetes mellitus. Therapeutic options for diabetes in cats are limited.

Objective

To evaluate the effects of pioglitazone in obese cats, which are predisposed to insulin resistance, to assess its potential for future use in feline diabetes mellitus.

Animals

A total of 12 obese purpose‐bred research cats (6 neutered males and 6 spayed females, 5–7 years of age, weighing 5.4–9.8 kg).

Methods

Randomized, placebo‐controlled 3‐way crossover study. Oral placebo or pioglitazone (Actos™; 1 or 3 mg/kg) was administered daily for 7‐week periods, with IV glucose tolerance testing before and after each period.

Results

Three mg/kg pioglitazone significantly improved insulin sensitivity (geometric mean [95% CI] 0.90 [0.64–1.28] to 2.03 [1.49–2.78] min ⁻¹pmol⁻¹L; P = .0014 versus change with placebo), reduced insulin area under the curve during IVGTT (geometric mean [range] 27 [9–64] to 18 [6–54] min∙nmol/L; P = .0031 versus change with placebo), and lowered serum triglyceride (geometric mean [range] 71 [29–271] to 48 [27–75] mg/dL; P = .047 versus change with placebo) and cholesterol (geometric mean [range] 187 [133–294] to 162 [107–249] mg/dL; P = .0042 versus change with placebo) concentrations in the obese cats. No adverse effects attributable to pioglitazone were evident in the otherwise healthy obese cats at this dosage and duration.

Conclusions and Clinical Importance

Results of this study support a positive effect of pioglitazone on insulin sensitivity and lipid metabolism in obese cats, and suggest that further evaluation of the drug in cats with diabetes mellitus or other metabolic disorders might be warranted.

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.

Owner Experiences in Treating Dogs and Cats Diagnosed With Diabetes Mellitus in the United StatesS

The objective of this study was to report owner experiences and satisfaction in treating a pet with diabetes mellitus using a descriptive report from an Internet-based survey. Descriptive analysis of results was performed, χ2 tests were used to detect differences in responses between dog and cat owners, and correlations were assessed using the nonparametric Spearman rank correlation. A total of 834 owners participated in the survey. More diabetic dogs (97%) than cats (82%) were treated with insulin injections. Insulin was administered twice daily in 87% of dogs and 73% of cats. Porcine lente and neutral protamine Hagedorn were the most commonly administered insulins in dogs. In cats, glargine and protamine zinc insulin were the most commonly used insulins. Most pets were not fed a prescribed diabetes diet. More cat (66%) than dog (50%) owners were satisfied with the diabetic control achieved. Cat owners were more likely to use home blood glucose monitoring. Treatment was considered expensive by the majority of owners. Few published reports follow diabetic pets after diagnosis or report owner satisfaction. The results of this study provide useful information that may help veterinarians better educate owners and set expectations regarding diabetes treatment and quality of life for diabetic pets.

Insulin detemir treatment in diabetic cats in a practice setting

Insulin detemir is a long-acting insulin analogue and may represent a valuable treatment option for diabetic cats. So far, only one study addressing detemir treatment of diabetic cats has been published, and this was based on an intensive blood glucose monitoring protocol. The aim of the current, retrospective study was to evaluate the effect of detemir therapy in diabetic cats in a general clinical setting. Fourteen diabetic cats with a follow-up period of at least 3 months were included. Data were collected from medical records at the University Hospital for Companion Animals, University of Copenhagen, Denmark. Thirteen of 14 cats achieved moderate or excellent control of clinical symptoms within the initial 3 months of detemir therapy, including five cats previously treated unsuccessfully with other types of insulin. Clinical improvements were noted after 1 month of therapy and continued over time. Three cats achieved remission within the initial 3 months and none experienced a diabetic relapse during the study period. One cat achieved remission after 13 months of therapy. Improvements in clinical symptoms were markedly better than indicated by blood glucose and serum fructosamine concentrations. The safety of detemir was very high, with only two reported episodes of clinical hypoglycaemia, neither of which required veterinary attention. Based on these results detemir can be recommended for the treatment of diabetic cats, including cats previously treated unsuccessfully with other types of insulin.

Survival time and prognostic factors in cats with newly diagnosed diabetes mellitus: 114 cases (2000-2009)

OBJECTIVE

To determine overall survival time and identify prognostic factors associated with survival time in cats with newly diagnosed diabetes mellitus.

DESIGN

Retrospective case series.

ANIMALS

114 cats with newly diagnosed diabetes mellitus.

PROCEDURES

Data for analysis included history, signalment, physical examination findings, hematologic and serum biochemical data, presence of ketoacidosis, and diagnosis of concurrent diseases at initial evaluation. The effects of possible predictors on survival time were determined by calculating hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Median survival time of diabetic cats was 516 days (range, 1 to 3,468 days); 70%, 64%, and 46% lived longer than 3, 6, and 24 months, respectively. Survival time was significantly shorter for cats with higher creatinine concentrations, with a hazard of dying approximately 5% greater for each increase of 10 μg/dL in serum creatinine concentration (adjusted HR, 1.005; 95% CI, 1.003 to 1.007). Ketoacidosis was not significantly associated with survival time (HR, 1.02; 95% CI, 0.590 to 1.78).

CONCLUSIONS AND CLINICAL RELEVANCE

Cats with newly diagnosed diabetes mellitus had a fair to good prognosis. High serum creatinine concentration at diagnosis was associated with a poor outcome, likely because of the adverse effects of renal dysfunction. Ketoacidosis apparently was not associated with decreased survival time, suggesting that this complication should not necessarily be regarded as unfavorable.

Factors associated with clinical remission in cats with diabetes mellitus

Type 2 diabetes mellitus is a common endocrine disease in cats. The aim of this study was to investigate factors that are associated with clinical remission in diabetic cats, and those that might influence survival time. Medical records of 29 cats with diabetes mellitus were evaluated retrospectively. Data collected from each record included breed, age, and sex, types of diet before and after admission, degree of weight loss, duration of clinical signs before admission, elevation of alanine aminotransferase activity and ketonuria at the time of admission, concurrent pancreatitis or renal failure, glipizide administration, insulin supplement, and survival time. The diet after establishing diagnosis (restriction to non-carbohydrate canned food) was the only factor that was significantly associated with achieving clinical remission (P < 0.001). Survival time of cats was positively associated (P = 0.004) with clinical remission status and the type of diet after admission (P = 0.04) and negatively associated with the presence of chronic renal failure (P = 0.04). This was the first report of feline diabetes mellitus from Taiwan.

New incretin hormonal therapies in humans relevant to diabetic cats

Incretins (gastric inhibitory polypeptide and glucagon-like peptide 1 [GLP-1]) are hormones released from the gastrointestinal tract during food intake that potentiate insulin secretion. Native GLP-1 is quickly degraded by the enzyme dipeptidylpeptidase-4 (DPP-4), which has led to the development of GLP-1 agonists with resistance to degradation and to inhibitors of DPP-4 activity as therapeutic agents in humans with type 2 diabetes. In healthy cats, GLP-1 agonists and DPP-4 inhibitors have produced a substantial increase in insulin secretion. Although results of clinical studies are not yet available, incretin-based therapy promises to become an important new research area in feline diabetes.

Diabetes from humans to cats

Diabetes mellitus is a common endocrinopathy in humans and in cats. The general prevalence of diabetes mellitus, and in particular of type 2 diabetes, has risen dramatically in recent years. This increase has often been linked to the rise in the obesity pandemic because obesity and the ensuing metabolic consequences constitute major risk factors for human type 2 and for feline diabetes. Feline diabetes shares many features of human type 2 diabetes in respect to its pathophysiology, underlying risk factors and treatment strategies. This review will briefly summarize major characteristics in the human and the feline disease and where available, point out the current knowledge on similarities and differences.