Diabetes Flashcards Preview

Stage 2: Inflammation > Diabetes > Flashcards

Flashcards in Diabetes Deck (48)
Loading flashcards...
1
Q

What is T1D?

A

Beta cell destruction leading to total insulin deficiency

2
Q

What are the two types of T1D?

A
  • Type a = autoimmune

- Type b = idiopathic

3
Q

What is T2D?

A

Insulin resistance + insulin deficiency - can’t make enough insulin to overcome insulin resistance even though might have a higher absolute level of insulin than normal

4
Q

What is gestational diabetes?

A
  • At the end of the 2nd trimester (25-28 weeks), insulin requirements increase 2-3x
  • Therefore in some women the pancreas can’t keep up
  • Same genetic risk as for T2D
  • Women screened at 26-28 weeks
5
Q

What are the genes involved in T1D?

A

HLA factors (common in hypothyroidism, coeliac)

6
Q

What is the beta cell reserve at the time of diagnosis?

A

25-30%

7
Q

Why do we not measure insulin in the body in T1D?

A

It is hard to measure and unstable

8
Q

What do we measure to see how much endogenous insulin there is in T1D?

A
  • C peptide

- 5 years post diagnosis most people are C peptide negative

9
Q

What are different ways that diabetes presents?

A

1) Hyperglycaemic emergency e.g. DKA or HHS
2) Osmotic symptoms (of hyperglycaemia)
3) Symptoms of chronic diabetes complications e.g. neuropathy, CV symptoms, retinopathy (up to ⅓ present with these)
4) Infection e.g. thrust, UTI, repeated skin infections e.g. boils
5) Detected by screening

10
Q

What are ketones?

A

By product of fatty acid oxidation used for energy (acidosis)

11
Q

What are the effects of an absence of insulin?

A

1) Uncontrolled endogenous glucose production
2) Tissue glucose deprivation so need to use free fatty acids
3) Lipolysis and proteolysis

12
Q

What clinical signs do lipolysis and proteolysis lead to?

A

1) Weight loss (mainly water)
2) Dehydration
3) Lack of energy

13
Q

Describe how symptoms develop in T1D

A

1) Excess glucose
2) Glucose excreted in urine
3) Water follows glucose
4) Osmotic diuresis
5) Polyuria
6) Dehydration
7) Thirst (decompensated diabetes, v dehydrated) and polydipsia

14
Q

Why is thirst less common in T2D than T1D?

A

Bc in T2D thirst has happened more gradually and slowly so have got used to drinking more water

15
Q

What makes symptoms worse in T1D?

A

Drinking sugary drinks when thirsty

16
Q

Why do people in T2D tend to just present with complications?

A

Bc the symptoms are less severe?

17
Q

How might dehydration and acidosis present in T1D?

A
  • Rapid weight loss and waking up in night to drink 3L water

- Shortness of breath, hyperventilation

18
Q

What is normally the trigger for admission to hospital?

A

Ketosis → nausea → vomiting → worsening dehydration

19
Q

What are the symptoms of peripheral neuropathy?

A
  • Numbness
  • Pain
  • Tingling
  • Tends to start in feet, rarely hands bc that is more central and tends to start peripherally
20
Q

What are the symptoms of autonomic neuropathy?

A
  • Abnormal sweating
  • Gastroparesis (N&V)
  • Diarrhoea
  • Postural dizziness
  • Erectile dysfunction
  • Incontinence
21
Q

What are the symptoms of radiculopathy (pinched nerve, one or more nerves affected)?

A
  • Pain

- Weakness (wasting)

22
Q

What is mononeuritis?

A
  • Isolated neuropathy of one nerve

- e.g. one eye nerve causing diplopia

23
Q

What happens in compression neuropathy?

A
  • Pain, tingling, weakness
  • e.g. carpal tunnel, ulnar nerve, lateral popliteal nerve
  • Compression of elbow - tennis elbow
  • In diabetes get deposition of glycated proteins around the nerve that can cause these symptoms
24
Q

Why might you get visual blurring e.g. sudden change in prescription in T2D?

A
  • Osmotic symptoms

- High glucose in the eye will cause the lens to become thickened bc of variability in glucose

25
Q

How is diabetes diagnosed in the presence of typical symptoms of hyperglycaemia?

A
  • Random venous plasma glucose ≥ 11.1 mmol/l

- OR HbA1c ≥ 48 mmol/mol (65%)

26
Q

How is diabetes diagnosed in the absence of typical symptoms?

A

On 2 separate occasions

  • Random or 2h post 75g glucose load venous plasma glucose ≥ 11/1 mmol/l
  • HbA1c ≥ 48 mmol/mol (≥6.5%)
  • Fasting venous plasma glucose ≥ 7 mmol/l
27
Q

What happens at HbA1c 6.5%?

A
  • Trigger for starting to get microvascular complications (why this is the cut off for diagnosis)
  • Don’t get any important retinopathy until this level
28
Q

What type of relationship is there between HbA1c and CVD risk?

A

Linear increasing, no set point where risk starts increasing

29
Q

Why is glucose not the main driver in macrovascular complications?

A
  • Bc levels below that for diagnosis increase the risk of a CVD event
  • By the time hit the diabetes range, risk is 3x normal, so even within the normal glucose range can see doubling of risk of CVD events
30
Q

What is the prediabetic (metabolic syndrome) HbA1c range where 50% of people will get diabetes in next 5 years?

A

43-47 mmol/mol (6.1-6.4%)

31
Q

How do you diagnose impaired glucose tolerance?

A
  • Fasting venous plasma glucose < 7 mmol/l

- 2h venous plasma glucose 7.8-11.1 mmol/l

32
Q

How do you diagnose impaired fasting glucose?

A
  • Fasting venous plasma glucose 6.1-6.9 mmol/l

- 2h venous plasma glucose < 7.8

33
Q

Describe the oral glucose tolerance test

A
  • 180g carbohydrate for 3 days before (adequate carb intake 3 days prior, if omit carbs get abnormally high response in glucose tolerance test and false positive)
  • Overnight fast
  • Sedentary during test
  • Fasting venous plasma glucose
  • 75g anhydrous glucose over 5 min
  • 2 hour venous plasma glucose
34
Q

How do you diagnose gestational diabetes?

A
  • Fasting venous plasma glucose ≥ 5.6 mmol/l

- 2h venous plasma glucose ≥ 7.8

35
Q

Describe the relationship between IGT/IFG and diabetes

A
  • IFG or IGT tends to merge into diabetes in 3 years

- Some people get IFG first and others get IGT

36
Q

What happens in IGT?

A

Fasting glucose ok but 2 hour is high

37
Q

What happens in IFG?

A

Fasting may be high but 2 hour is ok

38
Q

What are the clinical features of T1D?

A
  • Insulin deficient
  • Ketosis prone
  • HLA markers
  • Autoimmune
  • Onset peak in adolescence
  • Weight loss
39
Q

What are the clinical features of T2D?

A
  • Insulin resistant and deficient
  • Not ketosis prone
  • Polygenic
  • Increases with age (younger in ethnic groups with high prevalence)
  • Associated with obesity
40
Q

What are the aims of management of diabetes?

A

1) Remove symptoms of uncontrolled diabetes if present - reduce glucose rapidly
2) Avoid diabetes emergencies
3) Reduce risk of development/progression of complications of diabetes (what most treatment is based on, unlike other conditions)
4) Early detection and effective management of complications
5) Avoid adverse effects on QoL related to diabetes or treatment

41
Q

What are the modifiable risk factors for long term diabetes complications?

A

1) Glycaemic control
2) BP/HTN
3) Lipid profile/dyslipidaemia
4) Smoking
5) Exercise
6) Diet - decrease intake of carbohydrate
5) Obesity

42
Q

What are the non-modifiable risk factors for long term diabetes complications?

A

1) Age
2) Gender
3) Family history
4) Ethnicity

43
Q

What is a hard endpoint in clinical trials?

A

An outcome important to patients e.g. death, blindness, amputation, MI

44
Q

What is a surrogate endpoint in clinical trials?

A

A biomarker intended to substitute for a hard endpoint e.g. BP, HbA1c

45
Q

Why is tight glucose control in the first 10 years of both T1D and T2D important?

A

Bc those who are treated early on have a 42% lower risk of death (CVD) 30 years later

46
Q

Which is the only type of diabetes that needs exogenous insulin for survival (not just control), except in rare circumstances where other types may need it?

A

T1D

47
Q

What are the clinical stages of diabetes?

A

1) Normal glucose tolerance (normoglycaemia)
2) Impaired glucose regulation IGT and/or IFG (hyperglycaemia)
3) Not insulin requiring diabetes
4) Insulin requiring for control diabetes
5) Insulin requiring for survival diabetes

48
Q

What is the only treatment for T1D?

A

Insulin