Diabetes Mellitus Flashcards
How much of NHS’s total budget is spent on managing patients with DM?
8%
Define Diabetes Mellitus
Chronic conditions characterised by abnormally raised levels of blood glucose
How many types of DM are there and what are they?
7: T1DM T2DM Prediabetes Gestational Diabetes Maturity onset diabetes of the young (MODY) Latent autoimmune diabetes of adults (LADA) Other types
Define T1DM
Autoimmune disorder where the pancreatic insulin-producing beta cells of the islet of Langerhans are destroyed by T-cells. Thus resulting in absolute deficiency of insulin resulting in raised glucose levels.
What can poorly controlled T1DM lead to?
Diabetic Ketoacidosis, resulting in significant morbidity and mortality. Presents as nausea and vomiting, abdo pain, Kussmaul’s breathing, disorientation, confusion.
What are the main focuses of diabetes management?
Reducing incidence of MACROVASCULAR (ischaemic heart disease, stroke) and MICROVASCULAR (eye, nerve and kidney damage) complications
Define T2DM
Most common cause of diabetes. It is the relative deficiency of insulin due to an excess of adipose tissue ie. there is not enough insulin to go around all the excess fatty tissue, leading to raised blood glucose
Define Prediabetes
Term used for pts who don’t yet meet the criteria for a formal diagnosis of T2DM to be made, but are likely to develop the condition over the next few years, if no lifestyle interventions are taken.
Define Gestational Diabetes
Raised blood glucose levels during pregnancy. It is important to detect this, as if left untreated, it may lead to adverse outcomes for the mother and baby
Define MODY
Maturity onset diabetes of the young (MODY) = a group of inherited genetic disorders affecting the production of insulin. Results in younger patients developing symptoms similar to those with T2DM, ie. symptomatic hyperglycaemia with progression to more severe complications such as DKA.
Define LADA
LADA = Latent autoimmune diabetes of adults. Small group of pts develop autoimmune related diabetes later in life and they’re often misdiagnosed as having T2DM
What are less common types of DM?
Any pathological process which damages the insulin-producing cells of the pancreas may cause diabetes to develop. EG. chronic pancreatitis and haemochromatosis. Drugs may also cause raised glucose levels eg. glucocorticoids which commonly result in raised blood glucose levels.
Why do diabetes pts present with polydipsia and polyuria?
Polyuria and polydipsia are due to water being ‘dragged’ out of the body due to osmotic effects of excess blood glucose being excreted in the urine (glycosuria)
What are the 4 main investigations of blood glucose?
- Bedside finger prick blood glucose monitor
- One-off blood glucose - either fasting or non-fasting
- HbA1c measures the amount of glycosylated haemoglobin and represents the average blood glucose over the past 2-3mths.
- a glucose tolerance test - a fasting blood glucose is taken after which a 75g glucose load is taken. After 2hrs, a second blood glucose reading is then taken.
What are WHO’s diagnostic criteria?
Symptomatic patient:
- fasting glucose ≥ 7mmol/l
- random glucose ≥ 11.1mmol/l (or after 75g oral glucose tolerance test (OGTT))
In asymptomatic patients, the above criteria must be demonstrated on 2 separate occasions
WHO’s guidance on DM diagnosis using HbA1c
- ≥ 6.5% (48mmol/mol) = DM
- < 6.5% does not exclude DM (ie it is not as sensitive at fasting samples for detecting diabetes)
- in asymptomatic pts, test must be repeated to confirm diagnosis
misleading HbA1c results can be caused by increased red cell turnover.
HbA1c and fasting glucose values for prediabetes
HbA1c = 42-47mmol/mol (6-6.4%)
Fasting glucose = 6.1-6.9mmol/l
When is insulin used?
For T1DM and sometimes in poorly controlled T2DM
How is insulin administed?
SC
What are the main side effects of INSULIN?
HYPOglycaemia
Weight gain
Lipodystrophy
How is T1DM managed?
SC insulin - either analogue, human sequence of porcine
either short, immediate or long-acting
What 6 drugs can be used in management of T2DM?
Metformin Sulfonylureas Thiazolidinediones DPP-4 inhibitors (-gliptins) SGLT-2 inhibitors (-glifozins) GLP-1 agonists (-tides)
What is the first-line medication for T2DM management?
Metformin
When is metformin contraindicated?
In pts with an eGFR of < 30ml/min
What are the side effects of METFORMIN?
Gastrointestinal upset
Lactic acidosis (does not occur very much in clinical settings)
What is METFORMIN’s mechanism of action?
It increases insulin sensitivity
Decreases hepatic gluconeogenesis
What is the only T2DM drug given SC?
GLP-1 agonists (-tides)
all others are given orally
Name 2 examples of sulfonylureas
Gliclazide
Glimepiride
What is SULFONYLUREAS’ mechanism of action?
Stimulates pancreatic beta cells to secrete insulin
Side effects of SULFONYLUREA
HYPOglycaemia
Weight gain
HYPOnatraemia
What is the only currently available THIAZOLIDINEDIONE?
Pioglitazone
What are the side effects of THIAZOLIDINEDIONES?
Weight gain
Fluid retention
What is the mechanism of action of THIAZOLIDINEDIONES?
Activate PPAR -gamma (Peroxisome proliferator-activated receptor also known as the glitazone reverse insulin resistance receptor) receptor in adipocytes to promote adipogenesis and fatty acid uptake
What is the mechanism of action of DPP-4 inhibitors?
Increases incretin levels which inhibit glucagon secretion
Side effects of DPP-4 inhibitors (-gliptins)
Generally well tolerated but increased risk of pancreatitis
SGLT-2 inhibitors side effects
UTIs
Weight loss
Mechanism of action of SGLT-2 inhibitors
Inhibits reabsorption of glucose in the kidney
Mechanism of action of GLP-1 agonists (-tides)
Incretin mimetic which inhibits glucagon secretion
Side effects of GLP-1 agonists
Nausea and Vomiting
Pancreatitis
Weight loss
How are drugs prescribed in T2DM?
METFORMIN
if HbA1c > 58mmol/mol (7.5%)
add gliptin OR sulfonylurea OR pioglitazone OR SGLT-2 inhibitor
if still >58
metformin + gliptin + sulfonylurea
OR
metformin + pioglitazone + sulfonylurea
OR
metformin + sulfonylurea + SGLT-2 inhibtor
OR
metformin + pioglitazone + SGLT-2 inhibitor
BASICALLY, all can be used together, except GLIPTINs, which only combine with sulfonylureas
OR INSULIN
IF triple therapy ‘not effective, not tolerated or contraindicated’ AND BMI > 35 ->
metformin + sulfonylurea + GLP-1 mimetic
How are drugs prescribed in T2DM if pt cannot tolerate metformin?
GLIPTIN or SULFONYLUREA or PIOGLITAZONE
IF HbA1c > 58mmol/mol (7.5%)
ADD another type of drugs mentioned above
If still > 58
ADD INSULIN
What 6 dietary advice is given to T2DM pts?
- encourage high fibre, low glycaemic index sources of carbs
- include low-fat dairy products and oily fish
- control intake of foods containing saturated fats and trans fatty acids
- limited substitution of sucrose-containing foods for other carbs is allowable, but care should be taken to avoid XS energy intake
- discourage the use of foods marketed specifically at people with diabetes
- initial target weight loss in an overweight person is 5-10%
How regularly should HbA1c should be checked?
Every 3-6mths until stable, then 6mths
NICE encourages us to consider relaxing targets on who?
on a case by case basis, esp for pts who are older or frail, for adults with T2DM
HbA1c targets are no dependent on treatment. What are they for lifestyle, metformin and drugs that may cause hypoglycaemia
Lifestyle: 48mmol/mol (6.5%)
Lifestyle + metformin: 48mmol/mol
Includes any drugs which may cause hypoglycaemia (eg. lifestyle + sulfonylurea): 53mmol/mol (7%)
What HbA1c target do you aim for in a newly T2DM diagnosed pt who wants to try lifestyle treatment first
48mmol/mol (6.5%)
What should you do if when you review a T2DM pt after 6mths on metformin and his HbA1c is 51mmol/mol (6.8%)?
You increase his metformin from 500mg bd (x2 a day) to 500mg tds (x3) and reinforce lifestyle factors
What is the target HbA1c for a T2DM pt already on one drugs but HbA1c has risen to 58mmol/mol (7.5%)
53mmol/mol (7%)
Why must you assess for cardiovascular risk in T2DM patients?
If they have a high risk of CVD or established CVD or Chronic Heart Failure, they should start on metformin and once that has been established, start SGLT-2 inhibitors
What do you do if pt cannot tolerate METFORMIN? eg due to gastrointestinal side-effects
Switch to modified-release metformin
What do you do if metformin is contraindicated?
If risk of CVD/ Heart failure = SGLT-2 monotherapy
If not, = DPP-4 inhibitor or Pioglitazone or Sulfonylurea. SGLT-2 may be used if certain NICE criteria are met.
Why should metformin be titrated up slowly when first starting the medication?
To minimise the possibility of gastrointestinal upset
When should SGLT-2 inhibitors be given in addition to metformin?
if pt has high risk of developing CVD eg. QRISK ≥ 10%
pt has established CVD
pt has chronic heart failure
What must you do to metformin before starting SGLT-2 inhibitors?
Metformin should be established and titrated up before SGLT-2 introduction
When should you continue GLP-1 mimetics?
Only if there is a reduction of atleast 11mmol/mol (1%) in HbA1c and weight loss of atleast 3% of initial body weight in 6mths
In what 2 occasions should you consider switching one of the T2DM drugs for GLP-1 mimetics if triple therapy is not effective or tolerated?
- BMI ≥ 35kg/m² and specific psychological or other medical problems associated with obesity
- BMI < 35kg/m² and for whom insulin therapy would have significant occupational implications or weight loss would benefit other significant obesity-related comorbidities
What is NPH insulin?
Neutral Protamine Hagedorn insulin, also known as isophane insulin, is an intermediate-acting insulin.
It is used by injection under the skin once to twice a day. Onset of effects is typically in 90 minutes and they last for 24 hours.
How does NICE recommend taking human NPH insulin?
take at bed-time or twice daily according to need
What should you do when you review an established type 2 diabetic on maximum dose metformin and her HbA1c is 55 mmol/mol (7.2%)?
You do not add another drug as she has not reached the threshold of 58 mmol/mol (7.5%)
What do you do when a type 2 diabetic is found to have an HbA1c of 62 mmol/mol (7.8%) at annual review. They are currently on maximum dose metformin?
You elect to add a sulfonylurea
What are BP targets for T2DM pts?
Same as for those without T2DM.
if <80y/o;
- clinic BP <140/90mmHg
- ABPM/ HBPM <135/85mmHg
If >80y/o
- clinic BP <150/90mmHg
- ABPM/HBPM <145/85mmHg
What is the first-line medication for hypertension in T2DM?
ACEi or ARBs
ARB is preferred if pt has a black African or African-Caribbean family origin
What are considerations for antiplatelets in T2DM?
They should not be offered unless pt has existing CVD
When can statins be offered to T2DM pts?
Only to pts with a 10yr cardiovascular risk > 10% (using QRISK2)
First-line statin of choice is atorvastatin 20mg on (every night)
What to do for primary prevention (10yr cardiovascular risk ≥ 10% OR most type 1 diabetics OR CKD if eGFR < 60ml/min/m²)
Atorvastatin 20mg od (if non-HDL has not fallen by ≥40% then consider titrating upto 80mg)
What to do for secondary prevention (known ischaemic heart disease OR cerebrovascular disease OR peripheral arterial disease)
Atorvastatin 80mg od (once daily)
In what 8 conditions may HbA1c not be used for diagnosis?
- haemoglobinopathies
- haemolytic anemias
- untreated iron deficiency anemia
- suspected gestational diabetes
- children
- HIV
- CKD
- people taking medication that may cause hyperglycaemia eg. corticosteroids