Diagnosis of Type 2 Diabetes & IGT Flashcards
In what 2 ways can T2DM be diagnosed?
-
Plasma glucose (Once if symptomatic. Twice if asypmtomatic)
- Fasting glucose >=7 mmol/l
- Random glucose or OGTT >=11 mmol/l
-
HbA1C samples (Once if symptomatic Twice if asymptomatic) - WHO 2011
- >=48mmol/mol (6.5%)
- Not as sensitive as fasting glucose.
In what conditions can HbA1C NOT be used for diagnosis?
- Type 1 Diabetes - too rapid for HBA1C change
-
Medication - that raise blood glucose
- Steroids
- Antipsychotics
- Immunosupressants
- Antiretroviral drugs
- Pancreatitis or pancreatic surgery.
- Pregnancy - HBA1C lower in pregnancy.
-
Increased Red Cell Turnover
- Haemoglobinopathy - Sickle cell, thalassaemia, G6PD, Spherocytosis.
- Blood loss
-
Increased RBC lifespan
- Anaemias - B12/Folic acid & Iron deficiency & their treatment.
- Splenectomy.
- CKD & Renal dialysis - reduced HbA1c especially if treated with erythropoietin.
What are the 2 main types of Impaired Glucose Resistance/Pre-diabetes?
- Impaired fasting glucose (IFG)
- Impaired glucose tolerance (IGT)
What causes impaired fasting glucose?
IFG = Hepatic insulin resistance
What is the cause of impaired glucose tolerance?
IGT = Muscle insulin resistance
Which patients are more likely to develop CVD, IGT or IFG?
Patients with impaired fasting glucose (IFG)
Which patients are more likely to develop T2DM, IFG or IGT?
Patients with impaired glucose tolerance. (IGT)
What fasting blood glucose value means you can diagnose impaired fasting glucose (Hepatic resistance)?
6.1 to 6.9 mmol/l
What should people with IFG be offered?
They should all be offered an Oral Glucose Tolerance Test (OGTT) to rule out both diabetes and IGT.
What blood glucose values do you need to be diagnosed with impaired glucose tolerance (muscle resistance)?
Fasting blood glucose < 7.0mmol/l
AND
OGTT 2 hour value - 7.8mmol/l - 11.1mmol/l
What are the normal blood values for fasting, random sugar and HbA1C?
How should pre-diabetes be managed?
- Lifestyle modification
- Annual blood test follow up.
- Metformin - high risk adults - blood tests show progressing to T2DM despite lifestyle changes.
Steve, how do you remember which diabetes/prediabetes/IGR/IFG/IGT is worse?
Normal —>
Pre-diabetes/Impaired Glucose Resistance (IFG–> IGT) –>
T2DM
What HbA1C indicates someone is at high risk of diabetes?
HbA1c of 42-47 mmol/mol.
(Between normal and diabetes)
HbA1c reflects the change in blood glucose over what time period?
2-3 months though research is pointing to 2 to 4 weeks.