Diabetes Flashcards
What are the different types of diabetes?
- Diabetes mellitus
- Gestational diabetes
- Diabetes insipidus
- Secondary diabetes
What can cause secondary diabetes?
- Pancreatic damage
- Endocrine disease
- Hepatic cirrhosis
What is diabetes insipidus?
When Kidneys cannot hold enough water.
Decreased amount or lack of action of ADH - anti-diuretic hormone (this hormone stops you from losing water).
What are the different types of diabetes inspidius?
Cranial & Nephrogenic
Cranial - brain produces less ADH
Nephrogenic - Kidneys resist effects of ADH, so does not hold water
How do you treat cranial diabetes insipidus?
Give Vasopressin & Desmopressin (which is ADH)
How do you treat nephrogenic diabetes insipidus?
Give:
- Carbamazepine
- Thiazide
- Oxytocin
What are the side effects of desmopressin?
- Can lead to hyponatraemic convulsions
What DVLA advice is given for diabetic patients?
- ALL drivers treated with insulin must inform DVLA (and also let them know any history of diabetic complications like episodes of hypoglycaemia)
- Patients should know warning signs of hypoglycaemia.
- Patients must carry a capillary blood-glucose meter and test strips when driving.
- Blood glucose concentration must be checked no more than 2 hours before driving and every 2 hours while driving.
- Blood glucose conc should be at least 5mmol/l while driving.
Take snack if below.
Stop driving if less than 4mmol/l or warning signs develop.
Wait 45 minutes after blood glucose is normal, before continuing journey. - Always ensure fast acting carbohydrate in the car
- Resume driving when medical reports show hypo awareness has been regained.
Which drugs are most likely to cause hypoglycaemia?
- Insulin
- Sulphonylurea
- Meglitinides
What are the signs of hypoglycaemia?
- Hunger
- Anxiety
- Sweating
- Tingling lips
- Tremor
- Palpations
As levels fall lower:
- Confusion
- Weakness
- Incoordination
- Impaired vision
Severe
- Convulsions
- Inability to swallow
- Unconscious
- Coma
Can diabetic patients take alcohol?
- Drink in moderation and with food
Because alcohol can mask the symptoms of hypoglycaemia
What is the OGT test? What is it for?
Oral glucose tolerance test.
To see how well you can tolerate glucose.
So diagnose impaired glucose tolerance - diagnoses gestational diabetes.
What does this OGT test involve?
Measuring blood glucose conc after fasting for 8 hours.
Then measuring conc 2 hours after drinking a standard anhydrous glucose drink (polycal, OGTT oral)
What is HbA1c?
Glycated haemoglobin - red blood cells exposed to glucose
What does the HbA1c test show? And when must it be performed?
The average plasma glucose over the last 2-3 months.
Indicates body’s glycaemic control in type 2.
Expressed as mmol/mol
Performed at any time of the day.
When must HbA1c not be used?
- To diagnose type 1 diabetes
- In children
- During pregnancy
- Women up to 2 months postpartum
- Pt with symptoms of diabetes for less than 2 months
- Pt is ill
- Takes meds that can cause hyperglycaemia, pancreatic damage, kidney disease or HIV
What can HbA1c be used to predict?
- Microvascular complications
- Macrovascular complications
- Morality
Lower values represents lower risk of long term vascular complications
How often must type 1 n type 2 diabetic patients be monitored?
Type 1 - every 3-6 months (more frequently if blood glucose changes rapidly)
Type 2 - every 3-6 months until medication and hba1c are stable, then every 6 months
Which test diagnose type 2 diabetes?
Hba1c & fasting blood glucose test
Which test diagnose type 1 diabetes?
Random blood glucose test
What is type 1 diabetes?
Absolute insulin deficiency due to little to no insulin secretion caused by the destruction of beta cells in the pancreatic islets of langerhans.
What are the complications of diabetes?
- Retinopathy
- Nephropathy
- Neuropathy
- Premature CVD
- Peripheral arterial disease
What are the signs n symptoms of type 1 diabetes?
- Increased thirst
- Frequent urination esp at night
- Extreme hunger
- Unintended weight loss
- Irritability and mood changes
- Fatigue & weakness
- Blurred vision
How often must type 1 diabetic patient monitor their blood glucose levels?
At least 4 times a day (including before each meal & before bed)
What are the common target ranges for type 1 diabetes?
- HbA1c = below or equal to 48mmol/mol
- Fasting plasma glucose level upon waking = 5-7mmol/L
- Plasma glucose level before meals = 4-7mmol/L
- Plasma glucose after meals = 5-9mmol/L
- Plasma glucose when driving, at least = 5mmol/L
- Random plasma glucose conc = below 11mmol/L
Which type 1 diabetic patient may benefit from metformin being added to insulin?
- Patient overweight
- With BMI of over or equal to 25kg/m2 (or 23kg/m2 if Asian ethnicity).
- And those who wish to improve glucose control but reduce insulin use.
What are the different drug classes of antidiabetic drugs?
- Alpha Glucosidase inhibitors = Acarbose
- Dipeptidylpeptidase-4-inhibitors (gliptins) = alogliptin, linagliptin
- Glucagon-like peptide-1-receptor agonists = albiglutide, liraglutide, exenatide
- Meglitinides = nateglinide
- Sodium glucose co-transporter 2 inhibitors = canagliflozin, dapagliflozin
- Sulphonylureas - Gliclazide, tolbutamide, glipizide, glimepiride
- Thiazolidinediones - Pioglitazone
- Biguanides - metformin
What is the first choice antidiabetic drug and why? What happens to the dose?
Biguanide - Metformin.
Because it does not cause hypoglycaemia as does not stimulate insulin secretion.
The dose must be increased (if necessary) slowly, to prevent G.I side effects (OD-BD-TDS).
Offer modified release if standard is not tolerated.
What are the side effects of metformin?
- G.I side effects
- Lactic acidosis (discontinue if occurs)
How should metformin be taken?
- Taken with or after food
What are the contraindications for metformin?
- Acute metabolic acidosis (including lactic acidosis & DKA)
- Ketoacidosis
- Renal failure (can cause renal failure which increases risk of lactic acidosis)
- General anaesthesia (stop on morning of surgery)
- If eGFR is less than 30ml/min
Can metformin be given at pregnancy and breastfeeding?
Yes, for pre-existing and gestational diabetes.
Women with gestational diabetes should discontinue after birth.
What monitoring must be done for metformin?
Before treatment, monitor renal function; and annually.
What patient n carer advice must be given for metformin?
Inform of risk of lactic acidosis & how to recognise signs.
What are the signs of lactic acidosis?
- Dyspnoea (difficult/laboured breathing)
- Muscle cramps
- Abdominal pain
- Hypothermia (low temp)
- Asthenia (weakness/lack of energy)
Examples of sulphonylureas?
Short acting - Gliclazide, tolbutamide, glipizide
Long acting - glimepiride, chlorpropamide, glibenclamide
What can sulphonylureas cause?
Hypoglycaemia (especially with long acting ones) and weight gain
What are the cautions and contraindications for sulphonylureas?
Caution:
- Elderly (avoid; if necessary give short acting
- Patients with G6PD deficiency
- Pregnancy and breastfeeding
- Surgery (avoid before surgery, change to insulin)
Contraindications:
- Acute porphyria especially for gliclazide and tolbutamide
- Ketoacidosis
- Overweight
- Renal & hepatic impairment (or reduce the dose)
What are the side effects of sulphonylureas?
- G.I reactions (nausea, vomiting, diarrhoea, constipation)
- Hepatic impairment (Jaundice, hepatic failure, hepatitis)
- Allergic skin reactions in first 6-8 weeks (frequency unknown)
Which antidiabetic drug is an alpha glucosidase inhibitor?
Acarbose
What are the side effects of Acarbose?
- G.I side effects
- Interferes with sucrose absorption (therefore give glucose and not sucrose for hypoglycaemia, for patients on acarbose)
What MHRA advice is given with Thiazolidinediones?
It is associated with heart failure - increased risk when given with insulin.
And increased risk of bladder cancer
When should Thiazolidinediones treatment be continued?
Only continue if HbA1c decreases by at least 0.5% within 6 months of starting treatment.
What are the side effects of Thiazolidinediones?
- Bone fracture
- Weight gain
- Visual impairment
- Increased risk of infections & numbness
What monitoring needs to be done for Thiazolidinediones?
Monitor liver function and tell patients to report signs of liver toxicity
What are examples of Dipeptidylpeptidase-4-inhibitors?
Gliptins:
- Alogliptin
- Linagliptin
- Sitagliptin
- Saxagliptin
- Vidagliptin
What are the contraindications of gliptins?
Diabetic ketoacidosis
(not for linagliptin and saxagliptin)
What are the side effects of gliptins?
- G.I & skin reactions
- Acute pancreatitis (persistent severe abdominal pain)
When should gliptins be discontinued?
If symptoms of acute pancreatitis occurs (persistent severe abdominal pain)
Examples of Sodium glucose co-transporter 2 inhibitors (SGLT2)?
Flozins:
- Canagliflozin
- Dapagliflozin
- Empagliflozin
What MHRA advice is given with SGLT2?
Associated with risk of diabetic ketoacidosis.
Canagliflozin - increased risk of lower limb amputation (mainly toes)
What are the cautions and contraindications of SGLT2?
Caution - if taken with insulin or sulphonylureas, these doses may need to be reduced when given with flozins.
Contraindication - With Dapagliflozin avoid if eGFR is less than 15ml/min
What are the side effects of SGLT2?
- Urinary disorders
- Weight loss
- DKA
- Increased infection risk
Examples of Glucagon-like peptide 1 receptor agonists? (GLP-1 agonist)
- Semaglutide
- Exenatide
- Delaglutide
- Liraglutide
- Lixisenatide
- Albiglutide
When is GLP-1 agonists used?
Used as combination therapy, when other treatment options have failed
When should GLP-1 agonists be discontinued?
If acute pancreatitis occurs
What advice should be given with GLP-1 agonists?
Women of child bearing age, should be recommended to use effective contraception
Which antidiabetic drugs causes weight gain?
- Sulphonylurea
- Pioglitazone
Which antidiabetic drugs causes weight loss?
- SGLT2i - Flozins
- GLP1
Which antidiabetic drugs has no effect on weight?
- Metformin
- Gliptins
What is the mechanism of action for alpha glucosidase inhibitors (acarbose)?
- Inhibits intestinal alpha glucosidases.
- Delays digestion & absorption of starch & sucrose.
- Has a small but significant effect on lowering glucose
What is the mechanism of action for Biguanides - metformin?
- Decreases gluconeogenesis & increases peripheral utilisation of glucose.
- Acts only in the presence of insulin, so only effect when there is some functioning of pancreas cells
What is the mechanism of action for Dipeptidylpeptidase-4 -inhibitors (Gliptins)?
Inhibits dipeptidylpeptidase-4, to increase insulin secretion & lower glucagon secretion.
What is the mechanism of action for Thiazolidinediones (pioglitazone)?
Pioglitazone reduces peripheral insulin resistance, leading to reduction of blood glucose concentration.
What is the mechanism of action for glucagon-like peptide-1 receptor agonists?
Increases glucose dependent insulin secretion, slows gastric emptying
What is the mechanism of action for meglitinides?
Stimulates insulin secretion
What is type 2 diabetes associated with?
- Obesity
- Physical activity
- Raised bp
- Dyslipidaemia
- Has a tendency to develop thrombosis and therefore increases CV risk
- Can have long term microvascular & macrovascular complications
What is the treatment steps for type 2 diabetes?
Step 1 - lifestyle advice for 3 months
Steps 2 - Antidiabetic drugs if lifestyle control isn’t adequate
What are the contraindications of Pioglitazone?
- History of heart failure
- Previous or active bladder cancer
- Investigated macroscopic haematuria
What are examples of microvascular complications?
- Retinopathy
- Nephropathy
- Neuropathy
What are examples of macrovascular complications?
- Ischemic heart disease
- Peripheral vascular disease
- Cerebrovascular disease
