Type 2 Diabetes Flashcards
What percentage of diabetics are T2?
90%
Pathophysiology of T2DM
- Insulin resistance in the cells (mechanism not fully understood)
- Thought that GLUT transporters do not bind to cell membrane so glucose cannot be taken up into cells
- As glucose in blood remains high, further insulin is secreted by beta cells in pancreas (b cell hyperplasia)
- Beta cells also increase secretion of amylin (builds up and aggregates beta cells)
- Beta cells become exhausted and become dysfunctional and undergo hypertrophy & hypoplasia and die off
- As beta cells are lost, insulin decreases and glucose rises in blood
- Patients develop symptoms (polyphagia, glycosuria, polyuria, polydipsia)
- Still SOME circulating insulin
- DKA not likely because of this
Why doesn’t DKA commonly occur in T2?
Because there is still a small amount of circulating insulin
What is a Hyperosmolar Hyperglycaemic State (HHS) and why does it occur?
- Emergency presentation more common in T2DM
- Causes increased plasma osmolarity due to extreme dehydration and concentration of the blood
- Serious situation as dehydration can cause mental status changes
Risk factors for developing T2DM
- Obesity
- Lack of exercise
- HTN
- Family history of diabetes (parent or sibling)
- Race or ethnicity (unclear but Black, Hispanic, American Indian & Asian American at higher risk)
- Age (especially over 45)
What are the 3 P’s of diabetes symptoms
Polyphagia
Polydipsia
Polyurea
In pre-diabetes, the goal is to bring HbA1c levels below ..?
5.7%
Brief explanation of treatment of T2DM
Lifestyle changes (healthy eating, weight loss, exercise) Antidiabetic medication- metformin If metformin does not keep HbA1c below 7% = 2nd and 3rd antidiabetic medication added (dependent on patient factors) If antidiabetic medication does not work alone, + insulin
How do sulfonylureas (glimepiride/glipizide etc) work, what are the main side effects & who are they contraindicated in?
- Increase the amount of insulin the pancreas normally releases
- Can cause weight gain and biggest risk of hypoglycaemia
- Contraindicated in those with CKD
How do thiazolinedoiones (Pioglitazone) work and what are the side effects and contraindications?
- Help reduce insulin resistance so the insulin in body is more effective
- Reduced hepatic gluconeogenesis
- Can cause weight gain
- Contraindicated in those with severe heart disease or suspected HF as it causes fluid retention and increases CVD risk and lipid abnormalities
How do SGLT-2 inhibitors (dapagliflozin) work, what are the side effects and benefits and who are they contraindicated in?
- Reduces the amount of glucose absorbed by your kidneys and your blood by blocking SGLT2 receptor in kidney and increases glycosuria which decreases blood glucose
- Helps with weight loss
- Beneficial effect on BP and CV health in those with artherosclerosis
- Hypoglycaemia risk
- Contraindicated in those with CKD
How do GLP-1 (liraglutide, dulaglutide + exenatide) work, what are the benefits and side effects and who is it contraindicated in?
- GLP1 is a hormone secreted by the GI tract after meals that decrease glucagon levels and increase insulin production
- Causes feeling of satiety and reduces appetite
- Helps promote weight loss
- Nausea or vomiting is likely
- Contraindicated in severe CKD
- Good for patients with artherosclerosis or CVD and diabetic neuropathy
How do DPP-4 inhibitors (glipins) work, what are the benefits and side effects and is it contraindicated in any patients?
- DPP-4 degrades GLP-1 so using an inhibitor increases the amount of GLP-1
- Stimulates the pancreas to secrete more insulin
- Small risk of hypoglycaemia
- Can be used in those with CKD
What are the side effects of antidiabetic drugs? (4)
- Hypos
- Weight loss or gain
- Bloating and diarrhoea
- Feeling sick
What value indicates a high random glucose test?
Venous plasma concentration >11.1mmol/L
What value indicates a high fasting glucose test?
>7.0mmol/L
What is the cut off value for the oral glucose tolerance test (OGTT) to diagnose diabetes?
Fasting >7mmol/L
2 hour plasma concentration >11.1mmol/L
What does HbA1c measure and what is the cut off value for diagnosing diabetes?
Measures the proportion of glycated haemoglobin (as high glucose levels continue in blood, glucose sticks to Hb)
- It reflects how long glucose levels have been high for
48mmol/mol (6.5%) is the cut off value
What does a low C-peptide test result indicate?
Insulin deficiency
Normal range = 0.51 - 2.72 ng/mL
Low result of c peptide and high BG = T1DM
High level of c peptide but low BG = T2DM or Cushings syndrome
