Session 10-Diabetes

Question 1

What is diabetes?

Answer 1

When blood glucose is too high and over years leads to damage of small and large blood vessels causing premature death from cardiovascular diseases

Question 2

True or false: genetics has caused the diabetes epidemic

Answer 2

FALSE - environment

Question 3

What causes type 1 diabetes mellitus?

Answer 3

Loss of pancreatic beta cells (autoimmune response)

Question 4

What are the symptoms of type 1 diabetes mellitus?

Answer 4

Polyuria
Polydipsia
Weight loss
Tiredness
Acute onset in young patient

Question 5

Outline the progression of type 1 diabetes from insulin deficiency to possible death

Answer 5

Insulin deficiency -> catabolic state -> hyperglycaemia, ketoacidosis, dehydration -> (if untreated) coma -> death

Question 6

How does type 1 diabetes lead to ketoacidosis?

Answer 6

Lack of insulin and elevation of glucagon -> rapid lipolysis in adipose tissue -> excessive fatty acids converted to ketone bodies in liver -> ketoacidosis (+ketonuria)

Question 7

What are the effects of ketoacidosis?

Answer 7

Hyperventilation 
Nausea
Vomiting
Abdominal pain
Ultimately coma

Question 8

How does type 1 diabetes lead to hyperglycaemia?

Answer 8

Lack of insulin and elevation of glucagon -> hepatic glycogenolyis increases + hepatic gluconeogenesis increases + peripheral glucose uptake reduced -> hyperglycaemia

Question 9

What are the effects of hyperglycaemia?

Answer 9

Osmotic diuresis -> glucosuria + polyuria + dehydration (leads to polydipsia and confusion)

Question 10

What are the tests for type 1 diabetes?

Answer 10

• urine (glucose and ketones)
• finger prick (glucose and ketones)
• smell of acetone on breath
• blood sample for glucose urea, electrolytes HbA1c
• signs of dehydration
• BP, pulse, chest sounds
• resp rate

Question 11

What are the two major components in the treatment of type 1 diabetes?

Answer 11

• Diet and exercise

- Insulin therapy

Question 12

Why are oral glucose-lowering drugs generally avoided in type 1 diabetes?

Answer 12

Risk of hypoglycaemia

Question 13

What are the chronic macrovascular complications of diabetes mellitus?

Answer 13

• increased risk of stroke
• increased risk of MI
• poor circulation to periphery (feet)

Question 14

What are the microvascular complications of diabetes mellitus?

Answer 14

• diabetic eye disease
• retinopathy: damage to blood vessels in retina -> blindness
• nephropathy: damage to glomeruli -> microalbuminuria
• neuropathy: peripheral nerve damage
• diabetic foot: poor blood supply, damage to nerves, increased risk of infection

Question 15

What causes type 2 diabetes mellitus?

Answer 15

Insufficient insulin production from beta cells in setting of insulin resistance

Question 16

What % of type 2 diabetics are obese?

Answer 16

> 85%

Question 17

True or false: ketoacidosis occurs in type 2 diabetes

Answer 17

FALSE

Question 18

What is the HbA1c test?

Answer 18

Measure of glycated haemoglobin reflecting average glycaemia over a period of weeks

Question 19

What is glycosylation?

Answer 19

• Post-translational modification mediated by enzymes
• Defined carb molecule added to pre-determined region of protein
• Carb plays natural role in protein function

Question 20

What is glycation?

Answer 20

• Random non-enzymatic reaction
• Sugar covalently attached to protein creating unnatural glycated product
• Impairs protein function and stability

Question 21

True or false: glycosylation is associated with disease processes

Answer 21

FALSE - glycation (eg chronic hyperglycaemia results in glycation of proteins)

Question 22

What are the three major components in the treatment of type 2 diabetes?

Answer 22

• diet and exercise
• oral hypoglycaemic therapy
• insulin therapy

Question 23

How does metformin treat type 2 diabetes?

Answer 23

Reduces hepatic glucose output by inhibiting gluconeogenesis

Question 24

How does sulphonylurea treat type 2 diabetes?

Answer 24

Modulates ATP sensitive K+ channel function by decreasing open probability and stimulates insulin secretion