Diabetes Flashcards
What results of the oral glucose tolerance test would indicate impaired glucose tolerance?
Fasting blood glucose < 7
& 2-hr post glucose challenge or random glucose level of 7.8 - 11 mmol/L
What results of the oral glucose tolerance test / HbA1C would indicate diabetes?
A fasting blood glucose of 7mmol/L or more
OR
A random glucose or 2-hr post glucose challenge level of 11.1+
OR
HbA1LC of 48 mmol/L or 6.5% or above
(Note if patient asymptomatic, then these levels need to be shown on 2x separate occasions)
In which circumstances is HbA1LC unlikely to give a reliable results and therefore shouldn’t be used for diabetes screening / diagnosis?
haemoglobinopathies
haemolytic anaemia
untreated iron deficiency anaemia
suspected gestational diabetes
children
HIV
chronic kidney disease
people taking medication that may cause hyperglycaemia (for example corticosteroids)
In patients aged > 60 with new diagnosis of diabetes and weightloss what further investigation is important to do?
CT Abdomen should be performed if > 60 with new-diagnosis diabetes and weightloss - this is to exclude pancreatic cancer as an underlying cause of the DM
What is an appropriate target for blood glucose level for diabetic patients at end of life according to Diabetes UK?
A more relaxed target of 6 - 15 is suggested
At what eGFR should metformin be stopped?
eGFR < 30
At what age are diabetic patients invited for annual retinopathy screening?
From 12 years + for both type I and type II diabetics
(unless already under ophthalmologist with known diabetic eye disease)
What conditions affect the reliability of HBA1C?
Anything rhat affects RBC lifespan (e.g IDA, vitamin B12 deficiency the RCCs live for longer so HBA1C falsely elevated, in haemolysis, CKD, hypertriglyceridaemia (triglycerides over 10) recent blood transfusion in the past 6 months and haemochromatosis the HBA1C is falsely low)
Anything that affects Hb structure (e.g sickle cell anaemia, thallasaemia)
What is the typical presentation of MODY (Mature Onset Diabetes of the Young)
Normally autosomal dominant
so there is typically a history of early onset (<45) diabetes in multiple generations
Often misdiagnosed as Type I or Type II
They often are atypical for type 2 (ie normal BMI, lacking other cardiovascular risk factors)
Their diabetes can normally be managed either with diet alone or low doses of oral medicationIf suspect, fill out their risk in the calculator from www.diabetesgenes.org
What is the typical presentation of LADA (Latent Autoimmune Diabetes of Adulthood)
LADA is a variant of Type I diabetes (ie autoimmune, low C-peptide, positive anti -GAD antibodies) that presents later in life
Is a more gradual onset type I diabetes and so initially risks getting misdiagnosed asType II diabetes and then later at a risk of DKA etc if missed.
What percentage of patients with Type I diabetes are auto antibody negative?
About 10% !!
So having normal antibodies does not necessarily exclude Type I DM!!
According to the NICE suspected cancer guidelines, which patients require urgent CT abdomens to exclude pancreatic cancer?
Aged 60+ with weightloss and one of the following:
- New onset diabetes or sudden worsening of their diabetes
- Gastrointestinal symptoms
- Back pain
What is Pancreatic Exocrine Insufficiency and which proportion of diabetic patients may experience it?
Pancreatic exocrine insufficiency is due to insufficiency of the exocrine hormone release from the pancreas
Leads to gastric upset, steattorhoea (pale stools that are difficult to flush)
Occurs in pancreatitis, but also ~ 50% of Type I diabetes and 30% of Type II DM
Check faecal elastase if suspect!!! If low (<200) then confirms PEI.
Tx is Creon with food.
What is Type 3c diabetes?
Type 3c diabetes is diabetes secondary to pancreatic disease
(pancreatitis, pancreatic cancer)
Often need insulin and don’t respond well to oral medications
Suspect if initially diagnosed as Type II diabetes but end up needing insulin within 5 years of diagnosis !!!
What is the first line treatment for steroid-induced hyperglycaemia or steroid-induced diabetes?
Sulphonylureas (ie Gliclazide)!!
With what eGFR must metformin a) be reduced to max 500mg BD and b) stopped altogether
Reduce to 500mg BD when eGFR < 45
STOP metformin when eGFR < 30
What is the mechanism of action of SGLT2 inhibitors (Dapagliflozin, Empagliflozin etc) and what is it’s affect on weight?
SGLT 2 inhibitors = inhibit reabsorption of glucose in the kidneys = excretion of glucose into the urine
Pros:
Weightloss (moderate)
Moderate reduction in HBA1C
Subtle reduction in BP
No risk of hypos
SIGNIFICANT REDUCTION IN RENAL AND CARDIOVASCULAR MORTALITY
Cons:
Unlikely to reduce HBA1C if eGFR < 45
Genital infections / thrush / UTI
Can rarely cause a euglycaemic DKA (if it’s going to happen, normally happens in the first 6 months)
Dapagliflozin and Empagliflozin the most useful as licensed for all 3x Type II DM, CKD & HF and can use to a lower eGFR of around 20
Which populations of people should SGLT2 inhibitors be avoided?
Anyone with Type I, Type 3c or LADA (due to DKA risk)
Those with a prev history of DKA
Those with a ketogenic diet
Anyone acutely unwell
Anyone with a very elevated HBA1C (ie over 86) as theoretical ^ DKA
What are the pros and cons of sulphonylureas (Gliclazide)?
PROS:
- Very effective at bringing down blood sugar levels quite rapidly, so useful in those with very elevated HBA1C at diagnosis / steroid-induced hyperglycaemia
CONS:
- Risk of hypos - need access to capillary blood glucose monitoring and should inform DVLA !!!!
- Causes weight GAIN
What are the pros and cons of pioglitazone?
PROS
Useful in fatty liver disease / MASH
Cons:
Increased fracture risk
Theoretical risk of bladder cancer
Slow onset of action in reducing HBA1C
Weight GAIN
