Diabetes Mellitus Flashcards Preview

Z OLD ESA 1- Metabolism > Diabetes Mellitus > Flashcards

Flashcards in Diabetes Mellitus Deck (79):
1

What is diabetes?

When blood glucose is too high (hyperglycaemia)

2

What are the long term effects of hyperglycaemia?

Causes damage to small and large blood vessels

3

What is the result of damage to blood vessels due to hyperglycaemia?

Premature death from cardiovascular diseases

4

How is the problem of diabetes developing?

Huge and growing problem, cost to society is high and escalating

5

Why may the problem of diabetes be worse than anticipated?

High proportions to diabetes cases undiagnosed

6

What type of diabetes constitutes most of those that are undiagnosed?

Type 2

7

Why can type 2 diabetes go undiagnosed?

Because you can be quite well with diabetes for many years with blood sugars only marginally raised

8

What is the problem with undiagnosed diabetes?

Even with only small blood sugar elevations, over time damage is caused to the blood vessels

9

What are the potential causes of blood glucose rising in diabetes?

- Inability to produce insulin due to ß-cell failure and/or
- Insulin resistance preventing insulin working effectively- it doesn’t work at the receptor

10

What are the most important and common types of diabetes mellitus?

1 and 2

11

What are all types of diabetes mellitus characterised by?

Hyperglycaemia, other many other metabolic abnormalities present as well

12

How does diabetes mellitus present?

- Typical symptoms of hyperglycaemia 
- Symptoms of inadequate energy production

13

What are the typical symptoms of hyperglycaemia?

- Polyuria
- Polydipsia 
- Blurring of vision
- Urogenital infections

14

Why does hyperglycaemia cause blurring of vision?

Glucose comes out into the vitreous humour, altering the refractive index

15

Give an example of a urogenital infection common in hyperglycaemia

Thrush

16

What are symptoms of energy utilisation?

#NAME?

17

What does the severity of symptoms of diabetes depend on?

#NAME?

18

What must be obtained prior to diagnosing diabetes?

Laboratory confirmation

19

What tests can be used to diagnose diabetes?

- Fasting blood glucose
- Oral glucose tolerance test
- HbA1 c  (in type 2 only)

20

What do you do in an oral glucose tolerance test?

Give 75g glucose to drink after fasting, and take sample after 2 hours

21

What does the HbA1 c  test measure?

The amount of glucose attached to RBCs

22

What do you need to confirm diabetes?

- Symptoms and 1 abnormal test or
- Asymptomatic and 2 abnormal tests

23

Will a diabetic patient always test positive for all 3 tests?

No

24

What are the diagnostic criteria for diabetes?

- Fasting venous plasma glucose; ≥7.0 mmol/l
- Random venous plasma glucose; ≥11.1 mmol/l
- Elevated HbA1 c;  ≥6.5%
- Oral glucose tolerance test; fasting venous plasma glucose ≥7.0 mmol/l and/or 2 hr venous plasma glucose; ≥11.1 mmol/l

25

When is oral glucose tolerance test used?

Rarely, except for in pregnancy

26

What causes type 1 diabetes?

An absoloute insulin deficiency due to autoimmune and non-autoimmune destruction of ß cells

27

What causes type 2 diabetes?

Insulin deficiency and insulin resistance

28

What types, other than 1 and 2, of diabetes mellitus are there?

- Genetic defects of ß-cells
- Genetic defects of insulin action 
- Drug-induced diabetes
- Associated with other hormone disorders
- Iron overload-haemochromatosis 
- After pancreatectomy

29

What percentage of diabetes cases are type 1?

5-10%

30

How fast are ß-cells destroyed in type 1 diabetes?

Variable- can be very rapid to years

31

What is present in type 1 diabetes?

Antibodies; islet-cell and GAD 65

32

When does type 1 diabetes develop?

90% diagnosed under 30 years old, but can occur at any time

33

How has the prevalence of type 1 diabetes changed?

It has doubled ever 20 years since 1945

34

What is the aetiology of type 1 diabetes?

Not fully understood

35

What proves type 1 diabetes is not all genetic predisposition?

Twin studies

36

How does type 1 diabetes present?

- Rapid onset symptoms (usually weeks)
- Weight loss
- Polyuria 
- Polydipsia 
- In late presentation, may be vomiting due to ketoacidosis

37

Describe the typical patient presenting with type 1 diabetes

- Usually (not always) young-

38

What is insulins action on glucose metabolism?

- Enhances uptake of glucose by liver, muscle and adipose tissue 
- Inhibits liver glycogen breakdown

39

What is insulins actions on fat metabolism?

- Promotes clearance of free fatty acids 
- Prevents lipolysis

40

What is insulins effect on amino acid metabolism?

- Active transport of amino acids into cells 
- Inhibits catabolism of proteins 
- Inhibits gluconeogenesis in liver

41

What does insulin deficiency cause?

- Lipolysis 
- Hyperglycaemia

42

What is the result of lipolysis caused by insulin deficiency?

Increase in free fatty acids, therefore an increase in ketones, causing acidosis, which leads to cardiovascular collapse

43

What does hyperglycaemia cause?

Hyperosmolarity and glucosuria

44

What does glucosuria cause?

Electrolyte losses (particularly sodium and potassium) and dehydration

45

What does dehydration cause?

Renal failure

46

How is a vicious cycle set up with dehydration causing renal failure?

The renal failure causes further dehydration

47

What does the renal failure cause?

Shock, which causes cardiovascular collapse

48

What are the clinical signs of type 1 diabetes?

#NAME?

49

How is the presence of ketones in urine most easily measured?

Ketostick

50

What does presence of ketones in urine signify?

An absolute lack of insulin

51

How is type 1 diabetes treated?

Exogenous insulin

52

How is exogenous insulin given?

By subcutaneous injection several times a day

53

Why is diabetes treatment a specialised field?

The amounts and type of insulin required is dependant upon many factors

54

What happens if a type 1 diabetes diagnosis is missed?

Severe consequences- death, sometimes in hours

55

What should an ideal insulin do?

Mimic the characteristics of normal insulin

56

What is the pathology of type 2 diabetes?

Dual pathology- insulin resistance and relative insulin lack

57

What is the aetiology for type 2 diabetes?

Both causes have separate possible aetiologies- genetic and environmental factors

58

What is the most common single cause of insulin resistance?

Obesity

59

What shows that type 2 diabetes has genetic factors?

Twin studies

60

What factors have caused the type 2 diabetes epidemic?

Environmental, not genetic

61

Why does obesity lead to type 2 diabetes?

- Obesity leads to insulin resistance first
- This causes an increased secretion of inslin 
- Eventually the pancreas can’t keep up, causing pancreas exhaustion 
- Hyperglycaemia develops 
- As the pancreas is going at full speed, it is unable to accelerate- first phase secretion is lost and then basal insulin secretion
- Amyloid type deposits in the islet cells, causing ß-cell failure

62

What happens after bariatric surgery or a very low calorie diet?

- Within 7 days, fasting blood glucose normalises in type 2 diabetes before any weight loss 
- Massive fall in liver fat content and return of normal insulin sensitivity
- Over 8 weeks, first phase insulin release and maximal rates of insulin release return to normal
- This change is in step with decreasing pancreatic fat content normalising ß cell function

63

What does the effect of bariatric surgery or very low calories on type 2 diabetes mean?

It can be considered as a potentially reversible metabolic disorder precipitated by chronic intraorgan fat

64

What causes the improvements in glucose and insulin resistance following bariatric surgery or very low calorie diets?

- Calorific intake falls immediately post measure 
- Sudden reversal of traffic into the fat stores brings about profound change in intracellular concentration of fat metabolites 
- Under hypocalorific conditions, fat is mobilised first from the liver and other ectopic sites rather than from visceral or subcutaneous sites 
- Fasting glucose improved because of an 81% decrease in liver fat content and normalisation of hepatic insulin sensitivity

65

How does type 2 diabetes present?

Very variable symptoms 
- May have polyuria, polydipsia, weight loss 
- May be asymptomatic

66

Why are type 2 diabetes symptoms variable?

Because slower rise in blood glucose

67

How can type 2 diabetes be discovered when the patient is asymptomatic?

On routine screening

68

How old are type 2 diabetes patients

Usually, though not universally, older- most over 40, but seen increasingly in younger people and children

69

What % of type 2 diabetes patients are overweight/obese?

90%

70

Diagnostically, how can type 2 diabetes be differentiated from type 1?

Absence of ketones in urine

71

What does the absence of ketones in urine signify?

ß-cells are still producing some insulin, though not enough to control glucose levels

72

What happens if type 2 diabetes if left untreated?

- Gradual worsening of symptoms 
- Worsening/onset of complications of diabetes

73

What are the problems with gradual worsening/onset of diabetes complications?

- Significant morbidity 
- Mortality 
- Financial cost

74

Does a patient require diabetic control if they are asymptomatic?

Yes

75

How is type 2 diabetes treated

#NAME?

76

What lifestyle factor can be used to treat type 2 diabetes?

Exercise

77

What effect does exercise have on type 2 diabetes?

Improves insulin sensitivity

78

Give 8 drug therapies used for the treatment of type 2 diabetes

- Biguandines 
- Sulphonylureas
- Thiazolidinediones
- DPP4 inhibitors 
- α-glucosidase inhibitors
- SGLTs 
- GLP1 analogues
- Insulin

79

How are patients with diabetes monitored?

#NAME?