Diabetes mellitus - dogs and cats comparison

Question 1

At what age do pets get diabetes

Answer 1

Peak in dogs 7-10 yo, can get juvenile onset <1 year

Cats >4

Question 2

What is the sex predilection for diabetes?

Answer 2

possibly more female in dogs

approx 65% male in cats

Question 3

Which dogs are predisposed to diabetes?

Answer 3

Australian terrier
standard and miniature schnauzer, 
bichon fries, 
spitz, 
fox terrier,
miniature and toy poodle,
Samoyed, 
Cairn terrier,
Keeshond, 
Maltese, 
Lhasa
Apso, 
Yorkshire terrier

Question 4

In which breeds of dog is diabetes rare?

Answer 4

GSDs
Golden Retrievers
Boxer 
Collie
Shetland Sheepdog

Question 5

Which breeds of cat are affected?

Answer 5

Predisposition varies dependent on location - Burmese (in Australian, NZ and UK); Maine coon, Russian blue and Siamese (in USA)
Burmese - approx 10% over 8 are affect - 4x other breeds

Question 6

What is the pathophysiology of diabetes in dogs?

Answer 6

Resembles type 1 DM in humans - insulin dependent
• Type 2 extremely rare, or may not exist
• Congential β-cell hypoplasia/abiotrophy; immune-mediated β-cell destruction; β-cell loss; βcell exhaustion

Question 7

What is the pathophysiology in cats?

Answer 7

• Resembles non-insulin dependent DM in people
• Type 2 most common: 80-90% of cases
• “Other specific type”, or Type 3 DM <20% of cases in primary practice, due to:
pancreatitis,
pancreatic neoplasia,
acromegaly,
HAC
• Heterogeneous disease attributable to a combination of insulin resistance and β-cell failure

Question 8

What factors may be involved in the aetiopathogenesis of diabetes in dogs?

Answer 8

Genetics
Immune-mediated insulitis
Pancreatitis
Obesity*
Concurrent hormonal disease
(HAC, dioestrus-induced excess of GH, hypoT4)
Drugs (glucocorticoids, progestogens)
Infection
Concurrent illness (CKD, cardiac disease) Hyperlipidaemia

Question 9

What factors may be involved in the aetiopathogenesis of diabetes in cats?

Answer 9

Islet amyloidosis
Obesity
Pancreatitis
Concurrent hormonal disease (HAC, HS, hyperT4)
Drugs (progestogens, glucocorticoids)
Infection
Concurrent illness (CKD, cardiac disease)
Hyperlipidaemia (?)
Genetics (Burmese cat)
Immune-mediated insulitis (?)

Question 10

What is the means of diagnosing diabetes in dogs/ cats?

Answer 10

Persistent fasting hyperglycaemia and glucosuria (renal threshold for glucose 10-12mmol/L in a dog, 14-16mmol/L in a cat)

Question 11

What are the goals of therapy in dogs?

Answer 11

• Reduce or resolve clinical signs, prevent short-term complications and good QoL
• Good control – BG maintained between 5-14mmol/L
• Consistency in timing of injections, meals, type and amount of food, and exercise

Question 12

What are the goals of therapy in cats?

Answer 12

• Diabetic remission, resolve clinical signs, avoid clinical hypoglycaemia
• Maintaining ideal body weight and avoiding insulin-antagonistic drugs is important for maintaining remission

Question 13

What is the starting treatment for diabetes in dogs?

Answer 13

• Caninsulin® has a duration of effect of 10-14h in most
dogs (8-10h in most cats)
• Start on 0.25-0.5 IU/kg q12h

Question 14

What is the starting treatment for diabetes in cats?

Answer 14

• The duration of Caninsulin® is not adequate for most cats
• ProZinc® is the insulin of choice (based on the cascade; glargine is also an ideal choice, but is off cascade)
• ProZinc® 0.2-0.4 IU/kg q12h

Question 15

Outline the principles of feeding a diabetic dog

Answer 15

• Diets containing increased amounts of dietary fibre
• Dry food
• Nutritional requirements of any concurrent disease should take precedence
• Regardless of diet, most diabetic dogs can be well managed with feeding a consistent diet at consistent times with concurrent administration of an appropriate amount

Question 16

Outline the principles of feeding a diabetic cat?

Answer 16

• Dietary therapy very important
• High protein, low carbohydrate (or ultra-low) diet
• Wet food
• Meal-fed or grazer

Question 17

What are the methods/ aims of monitoring

Answer 17

• Control of clinical signs (PU/PD, PP, weight loss)
• Aim to keep BG below the renal threshold (10-12mmol/L in a dog, 14-16mmol/L in a cat) and to avoid hypoglycaemia
• Options for glycaemic monitoring
 Glucose curve (in-clinic vs at-home)
 Fructosamine
 Glycated haemoglobin

Question 18

Which other conditions typically cause a severe insulin resistance?

Answer 18

• Hyperadrenocorticism
• Acromegaly (cat)
• Progesterone excess (dioestrus in an intact female dog)
• Diabetongenic drugs (most notably glucocorticoids and progestins)

Question 19

Which conditions typically cause a mild or fluctuating insulin resistance?

Answer 19

• Obesity
• Infections
• Chronic pancreatitis
• Chronic inflammation
• CKD
• Hepatic dysfunction
• Cardiac dysfunction
• Hypo-/hyperthyroidism (dog/cat)
• EPI
• Hyperlipidaemia
• Neoplasia
• Glucagonoma
• Phaeochromocytoma
• Insulin autoantibodies

Question 20

What are the main canine diabetic complications

Answer 20

• Hypoglycaemia
• Cataract formation ** most common
• Diabetic neuropathy (subclinical more common)
• Diabetic nephropathy

Question 21

What are the main feline diabetic complications?

Answer 21

• Hypoglycaemia
• Systemic hypertension
• Diabetic neuropathy
• Diabetic nephropathy

Question 22

What is the prognosis for diabetes?

Answer 22

• Dependent on owner’s commitment, ease of glycaemic regulation, presence of reversibility of concurrent disorders and avoidance of chronic complications
• In a study of 347 dogs 1, 2 and 3 year survival was 40%, 36% and 33%, respectively; highest mortality in the first six months of treatment (similar life expectancy to a non-diabetic if survive this period)
• In a study of 114 cats median survival time was 516 days (range 1 – 3468 days), with 16.7% mortality in the first 10 days
• Cats achieving diabetic remission have longer survival times than cats that are persistently diabetic