Diabetes Flashcards
What is the definition of type 2 diabetes?
a metabolic disorder where persistent hyperglycaemia is caused by insulin resistance and hence a relative insulin deficiency
the body is still making insulin, but this insulin does not work as well
How is the definition of type 1 diabetes different to type 2?
In type 1, there is an actual insulin deficiency
the pancreas is not producing the required amount of insulin, but the insulin present is normal
What is the prevalence of diabetes?
What proportion of this is type 2?
- 4.9 million people in the UK have diabetes
- 90% of these have type 2
- there are nearly 1 million people with undiagnosed type 2 diabetes
Why are there so many cases of undiagnosed type 2 diabetes?
it can present with no or very minimal symptoms that have a gradual onset over a long period of time
How are the vast majority of cases of type 2 diabetes identified?
- through annual health reviews for other long-term conditions (e.g. HTN, heart conditions)
- an HbA1c test is performed
- patients with many risk factors are screened regularly or on a one-off basis
What are the 7 main risk factors for developing type 2 diabetes?
- obesity (80-85% overall risk)
- family history
- ethnicity
- history of gestational diabetes
- certain medications
- polycystic ovary syndrome
- metabolic syndrome
How does family history increase the risk of diabetes?
lifetime risk is 15% if one parent has diabetes
or 75% if both parents have diabetes
the risk may be even higher if other RFs are present
How does ethnicity affect chances of developing diabetes?
the risk is 2 to 4 times higher in someone of Asian, African or Afro-Caribbean descent
What medications can increase the risk of diabetes?
- corticosteroids
- beta-blockers
- statins
- thiazides
What measures are in place to monitor someone who had gestational diabetes?
- this is diabetes that develops during pregnancy but completely resolves afterwards
- the risk is 7 times higher in these individuals
- they are monitored with annual screening
Why might polycystic ovary or metabolic syndrome increase risk of diabetes?
they both cause insulin resistance
What are the symptoms that someone with type 2 diabetes may present with?
- they are similar to type 1 diabetes, but much more mild and gradual onset
- urinary frequency, especially nocturia
- fatigue
- constant thirst
- genital itching / recurrent thrush
- prolonged healing of cuts / wounds
What signs might someone with type 2 diabetes present with?
- acanthosis nigricans
- weight loss (might prompt you to think of something more serious)
When would you consider referring urgently to a diabetes specialist?
- if symptoms have developed rapidly (within 2 months)
- there are no risk factors for type 2 diabetes
- the person is young (< 40)
What is acanthosis nigricans?
hyperpigmentation associated with insulin resistance
- the skin will feel thicker
- can occur anywhere on the body, but usually axillae, neck or groin
How is type 2 diabetes diagnosed?
there must be persistent hyperglycaemia in an adult
- in the presence of RFs and/or mild symptoms
- no features of type 1 diabetes
- not acutely unwell
test is repeated in 2 weeks to confirm diagnosis
in primary care, HbA1c is used
What tests can be used to determine if someone has persistent hyperglycaemia?
- HbA1c > 48 mmol/mol
this is a better indicator of glucose exposure than random blood glucose readings
- fasting glucose > 7.0 mmol/l
- random glucose > 11 mmol/l
In what 2 situations can HbA1c NOT be used for diagnosis?
- if someone has had rapid changes in their blood glucose levels
- if someone has abnormalities of their haemoglobin
this is because HbA1c looks at glucose storage by RBCs over the last 3 months
rapid changes are associated with type 1 diabetes - HbA1c cannot be used
In what individuals can HbA1c not be used for diagnosis?
- suspected type 1 diabetes
- children / young people
- pregnancy
- symptoms for less than 2 months
- certain medications (ARVs, steroids, olanzapine)
- recent pancreatic surgery / damage
- kidney failure
- anaemia / haemoglobinopathies, recent transfusion
these are all likely to involve rapid changes in glucose
Can type 2 diabetes be diagnosed in young people and children?
- it needs specialist assessment as type 1 is far more likely
- but T2DM can exist in children - particuarly Asian, Black and Afro-Carribean descent
What is pre-diabetes?
- individuals with a HbA1c range 42 - 47
- they are above the normal level of 41 or below
- but they are not at the stage where they will develop complications from their diabetes (48)
Why is it important to recognise pre-diabetes?
these people are likely to develop diabetes within the next 10 years
- they are offered annual monitoring and lifestyle advice to prevent the onset of diabetes
What is the leading cause of death in T2DM?
cardiovascular disease including stroke and PVD
- 2.5x increased stroke risk
- 2.5x increased risk of MI / heart failure
75% of people with T2DM will die from a cardiovascular complication
What has a more significant impact on CV risks than treating the hyperglycaemia?
management of blood pressure and cholesterol
- lipid profile performed annually
- blood pressure monitored every 6 months
How do you screen for and monitor renal disease in diabetes?
monitor eGFR and ACR annually
- this is performed more regularly if they have severe renal disease, HTN or risk factors for kidney disease
Why can diabetes lead to renal disease?
- diabetic nephropathy (direct damage to kidneys from raised glucose)
- HTN
- renal atheroma
- ischaemia (due to glucose damaging renal arterial supply)