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)
Why is it important to monitor eGFR and ACR in T2DM?
T2DM is the commonest cause of CKD
but, someone is far more likely to die from CVD before reaching the stage of needing dialysis
reduced eGFR and raised ACR are independent risk factors for CVD
if someone has T2DM and CKD, their risk of CVD is amplified
blood pressure & cholesterol control are as important as hyperglycaemia
What are the typical symptoms and signs of peripheral neuropathy?
typically associated with pain that is nocturnal, bilateral and in a glove & stocking distribution
- numbness
- burning / shooting pain
- tingling
- paraesthesia
- symmetrical
What causes foot complications in T2DM?
- a combination of peripheral neuropathy (damage to the nerve endings in the feet and hands)
- and peripheral arterial disease
What active foot conditions are associated with T2DM?
- ulceration
- ischaemia
- soft tissue / bone infection
- gangrene
a monofilament is used at annual screening to monitor this
How do foot ulcers typically present?
- tend to be seen in patients who have had poor glucose control over many years
- develop in pressure areas
- start as a haemorrhagic blister and progress
- often painless (neuropathy causes a lack of pain sensation in the foot)
- have a “punched out” appearance
What are the major risks of foot ulcers?
- they can develop into skin infections and gangrene
- they can become full-thickness and result in bone infections, which can result in amputation and progression to sepsis
What is autonomic neuropathy?
occurs when high levels of glucose damage the nerves of the autonomic nervous system
What are the potential symptoms of autonomic neuropathy?
- erectile dysfunction
- diarrhoea
- bladder dysfunction
- postural hypotension
- gastroparesis
- sweating abnormalities
important to ask about these at annual review
Why is it important to screen annually / bi-annually for retinopathy?
- 2/3 of people will develop this within 20 years of diagnosis
- 25% of people with diabetes have retinopathy
- T2DM is the leading cause of preventable sight loss
What are some important things to mention in a consultation when making a diagnosis of T2DM?
- check the patient’s current understanding of the condition
- explain the modifiable RFs, importance of regular check-ups and lifestyle changes
- signpost to online resources for further information
- organise a follow-up appointment to see how they are doing
What is a good way to explain T2DM to a patient?
blood sugar levels are too high, which can cause serious problems in the heart, eyes, kidneys, feet and nerves
- insulin is a hormone made by the pancreas after eating
- it helps the body to take up glucose from the blood and use it for energy
- in T2DM, the insulin does not work as well as it should or there is not enough of it
What other factors are important to discuss in a T2DM consultation?
- the need for an annual review & 6-monthly BP & HbA1c
- annual flu and pneumonia vaccinations
- NHS prescription exemption
- referral for retinal screening
What is the key lifestyle advice to offer a patient?
- weight loss is the single most important factor in improving glycaemic control
- consider healthy carbohydrates (low GI, swapping for wholegrain)
- low GI foods release glucose more slowly so avoid large post-meal rises
What are the HbA1c targets of someone with diabetes that takes no medication, takes metformin and a drug that can cause hypoglycaemia?
What are the HbA1c targets for someone who is already on diabetes treatment?
53 mmol /mol
How often should HbA1c targets be reviewed?
- HbA1c should be checked every 3-6 months until it remains stable
- following this, it is checked 6-monthly
What other lifestyle advice is relevant?
- exercise - ideally 150 mins mod or 75 mins a week of high intensity + strength/conditioning 2x week
- smoking cessation (increases CV risk)
- alcohol prolongs / exacerbates hypoglycaemia from medications
When someone is diagnosed with T2DM, when should medication be given?
- oral medications are given when glycaemic control remains suboptimal even after lifestyle changes
- usually metformin is given when HbA1c remains > 48 mmol/mol after 3 months of lifestyle changes
Why do patients with T2DM often need multiple drug treatment / changes in medication?
- most medications (other than insulin) only moderately lower HbA1c
- some people do not respond to certain treatments, so a change of therapy is required if there is no change in HbA1c after 6 months
What is usually the first line medication for T2DM?
metformin
What should be established prior to prescription of metformin?
What additional medication is given in this group?
!! assess cardiovascular risk !!
- if patient has high-risk, establised CVD or heart failure - add an SGLT-2 inhibitor once established on metformin
When should a second medication be added in addition to metformin?
- metformin is titrated up + encouraging lifestyle changes to aim for HbA1c of 48 mmol/mol
- a second drug is only added when HbA1c rises ABOVE 58 mmol/mol
When is metformin contraindicated?
What are the side effects?
contraindicated with renal, hepatic or cardiac failure due to risk of lactic acidosis
What are the common side effects associated with metformin?
gastrointestinal side effects such as:
* diarrhoea
* bloating
* epigastric discomfort
If metformin is not tolerated due to GI side effects, what is done?
switch to modified-release metformin
What medication is given when metformin is contraindicated?
if high CVD risk:
* monotherapy with SGLT-2 inhibitor
if low CVD risk:
* DPP-4 inhibitor OR
* pioglitazone
* OR sulfonylurea
If HbA1c remains >48 after 6 months of metformin, what is done?
second-line therapy is commenced
this could involve:
* DPP-4 inhibitor
* pioglitazone
* sulfonylurea
* SGLT-2 inhibitor (only if NICE criteria met)
medication choices depend on individual circumstances + patient preference
When are gliptins (DPP-4 inhibitors) used for management of diabetes?
- they are safe for use in renal failure
e.g. sitagliptin or saxagliptin
When are SGLT-2 inhibitors used in the management of T2DM?
they are given when a patient has chronic heart failure, established atherosclerotic CVD or QRISK score > 10%
If at any point during treatment, CVD risk changes and QRISK becomes > 10%, what should be done?
a SGLT-2 inhibitor should be added
What happens when a patient has a HbA1c > 58 mmol/mol and they are taking metformin + another drug?
another drug from the list of second-line therapy is added
or
insulin based treatment starts
If triple therapy is not effective, what can be considered?
one of the drugs can be switched for a GLP-1 mimetic when:
- BMI > 35 with any medical problems associated with obesity
- BMI < 35 but insulin has occupational implications
What is the purpose of the QRISK tool?
it measures the risk that an individual will have a heart attack or a stroke in the next 10 years
When should the QRISK tool not be used?
- patients who already have CVD
- patients who are at high risk of CVD due to familial hypercholesterolaemia / inherited disorders
- patients > 85 - they are at high risk due to age alone
In which groups is CVD already considered high risk and QRISK is not necessarily needed?
- type 1 diabetes
- CKD stages 3, 4, & 5
What should be done if someone has a QRISK score >10%?
they are offered a atorvastatin 20mg od to lower their circulating cholesterol
this reduces the risk of atherosclerosis + makes existing plaques more stable so emboli are less likely
What medication is given to someone with known CVD for secondary prevention?
atorvastatin 80mg od
What are some of the side effects of statin treatment?
- muscle tenderness
- tiredness
- abnormal LFTs
If someone has a QRISK score < 10%, what should be done?
- offer lifestyle advice and risk assessment in 5 years time
