Diabetes Flashcards
What is Type 1 diabetes?
Insulin- dependent
Autoimmune disorder
Pancreas produces little or no insulin
Diagnosed in children or teens (10-14)
What is Type 2 diabetes?
Insulin- resistant
Pancreatic beta cells don’t produce sufficient insulin
Diagnosed later in life
Lifestyle result- obesity, lack of exercise
What is gestational diabetes?
Occurs during pregnancy
Usually in 2nd trimester then disappears when baby is born
Possibly due to hormone changes
Tests for diabetes?
Random glucose
Fasting glucose
Oral glucose test
Hba1C
Fasting Glucose
No food or drinks for 8-10 hours before
Normal- 3.9- 5.5 mmol/l
Pre- diabetic- 5.5- 6.9 mmol/l
Diabetic- >7 mmol/l
Random Glucose
Test taken at any point
11.1 mmol/l indicates diabetes
Oral glucose tolerance test
Fasting for at least 8 hours
Plasma measured right before and 2 hours after drinking 75g glucose dissolved in water
Impaired- 7.9- 11 mmol/l
Diabetes- 11.1 mmol/l
Hba1C
Irreversible reaction between haemogloblin A and glucose
Amount of Hba1C proportional to glucose present
Measures over 3 months
Pre- diabetic- 42- 47 mmol/l
Diabetic- >48 mmol/l
Symptoms of diabetes
Early symptoms of hypoglycamia
Dehydration, thirst, excessive urination, nausea/ vomiting, increased appetite, weight loss, poor wound healing
What is DKA?
Diabetic Ketoacidosis
Lack of insulin means glucose can’t be used as an energy source
Energy starts coming from fat supply
Ketones cause pH of blood to become acidic
Blood glucose rises as liver still synthesises it
Causes dehydration
Symptoms of DKA
Feeling thirsty, urinating often, high blood glucose, high ketone levels
Feeling weak, dry/ flushed skin, nausea/ vomiting, fruity smelling breath
How does hyperglycaemia occur?
Loss of insulin- stimulated glucose uptake into target cell
Loss of insulin- mediated repression of gluconeogenesis
Cause of type 1 diabetes?
Destruction of beta cells results in insulin deficiency and hyperglycaemia
Occurs in genetically susceptible individuals, likely as a result of an environmental trigger
Causes of type 2 diabetes?
Characterised by high blood glucose levels as a result of insulin resistance of target tissues, insufficient production/secretion of insulin (beta cell dysfunction
Strong link between obesity and type 2 diabetes
What is metformin?
Biguanide
First line oral glucose lowering agent
No weight gain
No hypoglycaemia
Never took away just added
What is sulfonylureas?
Stimulate insulin secretion from pancreatic beta cells
Can cause hypoglycaemia
Gliciazide, glipizide
What is Meglitinides?
Similar mechanism of action as sulfonylureas but rapid onset and short duration
Taken before meals
Repaglinide
What are Thiazolidinediones?
Increase insulin sensitivity by stimulating the expression of insulin-sensitising genes
They are insulin sensitizers
Pioglitazone
What are GLP-1 analogues?
Active GLP-1 and GIP responds to increased concentration of glucose in GI tract
Causes insulin effect
Semaglutide (ozempic), Dulaglutide (trulicity)
What are DPP4 inhibitors?
DPP4 degrades incretins therefore inhibitors potentiate insulin effect
Sitagliptin, Alogliptin, Linagliptin (+ metformin)
Other drugs
Empagliflozin
Canagliflozin
Dapagliflozin
Surgery
Gastric band, bariatric surgery
Type 2
What are the 3 types of insulin?
Short acting
Long acting
Intermediate acting
What is biphasic insulin?
Pre-mixed insulin preparations containing various combinations of short-acting insulin or rapid-acting insulin analogue together with an intermediate-acting insulin
Why is Humulin I medium acting?
Contains protamine
Causes clustering of insulin which limits diffusion through capillary walls
Injecting insulin
Insulin as oral formulation would be degraded in stomach by proteases
Sub- cutaneous, diffuses into blood vessels and into bloodstream
Should be stored in fridge under 25’C
Insulin treatment in type 2?
Alongside oral anti-diabetics
Basal insulin is usually a suitable first step with once- or twice-daily intermediate or long-acting insulin
Biphasic insulin can be used if diabetic control is particularly poor
Basal-bolus regimen can be introduced if blood glucose remains inadequate
What is an insulin pump?
Alternative to injections
Helps improve overall control
Pump delivers a varied dose of rapid acting insulin continually during day and night (this is known as the ‘basal’ rate and is set to suit the individual)
When food is eaten can give an additional “bolus dose” of insulin by pressing specific buttons
