Diabetes Flashcards
What is the pathophysiology behind T1DM
Autoimmune destruction of beta cells in the pancreas which causes an absolute deficiency of insulin
How does type 1 DM present
Shorter history
- Weight loss - unable to use glucose for energy so use fat and muscle instead
- Polydipsia - incresed thirst due to lots of urine produced
- Polyuria - glucose lost in urine
- tiredness
Which infections are more common in diabetics and why
Thrush and UTIs
Due to high sugar environment easier for bacteria to multiply
What is LADA
Latent autoimmune diabetes of adults
Form of T1DM with slower progression to insulin dependence
What are the glucose targets for T1DM patients
5-7mmol/L on waking
4-7mmol/L before meals and at other times of the day
How many times do T1DM patients need to monitor their insulin a day
4x a day including before each meal and before bed
How is DM diagnosed
Random blood glucose >11mmol/L
fasting glucose >7mmol/L
Oral glucose tolerance tests 2hrs later after 75g of glucose 2x venous gluose >11mmol/L
HbA1c >6.5% (>48mmol/L)
1 positive test result and symptomatic
or 2 positive test results and asymptomatic
Which HbA1c results suggest prediabetes
42-47mmol/L
5.7-6.4%
What is the pathophysiology behind T2DM
Normal or increased insulin secretion but relative insulin resistance
Resistance due to increased blood glucose levels so muscle and adipose tissue stop taking up glucose if oversaturated
Increased insulin production so increased absorption of glucose in cells (already overaturated)
therefore exhaustion of beta cells
How might T2dm present
Polydipsia Polyuria Hx of blurred vision Itchiness Peripheral neuropathy Recurrent thrush/UTIs Fatigue
How is T2DM managed
Diet and exercise to decrease insulin resistance
If HbA1c 6.5% (48mmol/L)
oral hypoglycaemics - metformin 1st line
1st intensification HbA1c (7.5%) Metformin + DPP4 i e.g. sitagliptin Metformin + pioglitazone Metformin + sulfonylurea e.g. gliclazide Metformin + SGLT 2 inhibitor
Aim for a HbA1c of 7.0%
2nd intensification
Triple therapy on insulin based therapy
HbA1c therapy >7.5%
When are rapid acting insulins used
Taken before a meal used with long acting insulins e.g. Novorapid
When are short acting insulins used
30mins before meal e.g. Actrapid
When are intermediate acting insulins used
covers blood glucose when rapid stops working. Works for about 7hours
given at bedtme to cover night time
Patients should be aware of the risk of becomig hypoglycaemic
When are long acting insulins used
Given at bedtime to cover overnight Combined with rapid and short acting Taken OD or BD e,g. Levemir Glargine
What are the BM targets whilst on insulin therapy
Fasting 5-7mmol/L
before meals 4-7mmol/L
What is the MOA of metformin
Increases insulin sensitivity
Decrease hepatic gluconeogenesis
What are the side effects of metformin
GI upset - nausea, diarrhoea
Lactic acidosis
Which patients cannot take metformin
Patients with an eGFR of <30ml/min
What is the MOA of sulfonylureas
Stimulates beta cells to secrete insulin
- Glicazide
- Glimepinide
What are the side effects of Sulfonylureas
Hypoglycaemia
Weight gain
Hyponatraemia
What is the MOA of pioglitazone
Activates PPAR gamma receptor in adipocytes to promote adipogenesis and fatty acid uptake
What are the side effects of pioglitazone
Weight gain
Fluid retention
What is the MOA of DPP4 inhibitors (gliptins)
Increases incretin levels which inhibit glucagon secretion e.g. sitagliptin
What are the side effects of gliptins
increased risk of pancreatitis
however generally well tolerated