1b T2DM Flashcards
What is type 2 diabetes?
A condition in which the combination of insulin
resistance and beta-cell failure result in
hyperglycaemia
What is T2DM associated with?
Obesity
How is the resultant hyperglycaemia due to T2DM initially managed?
changes to diet / weight loss
Can you get diabetic ketoacidosis in T2DM?
Yes
What is LADA?
Autoimmune diabetes leading to insulin
deficiency can present later in life = latent
autoimmune diabetes in adults
Describe the age distribution of type 2 diabetes?
Traditionally thought to be only late adult hood condition
Now increasing evidence that is can occur earlier in life as well
In which ethnic groups is T2DM prevalence the highest?
*Greatest in ethnic groups
that move from rural to
urban lifestyle
Above what level of HbA1c levels indicative of Diabetes?
greater than or equal to 48 mmol/mol
Between what range of HbA1c levels indicates prediabetes?
42-48 mmol/mol
What are some features of prediabetes?
Impaired glucose tolerance
Impaired fasting glycaemia
What is needed to make a diagnosis of T2DM?
High random glucose with symptoms
Between what levels of fasting glucose would indicate impaired fasting glycaemia?
6-7
Between what levels of 2hour oral glucose would indicate impaired glucose tolerance?
7.8-11.1
What is meant by an insulin deficiency in T2DM?
Insulin is produced by pancreatic beta-cells but not enough to overcome insulin resistance, therefore RELATIVE INSULIN DEFICIENCY
What happens in long-duration diabetes?
beta cell failure may progress to complete insulin deficiency - therefore highly important to continue on insulin due to the risk of ketoacidosis
What is lost in patients with type 2 diabetes?
The first phase insulin release
Describe the graphs showing plasma insulin levels over time for patients with a normal glucose tolerance and patients with diabetes?
After the IV glucose challenge, for the patients with normal glucose tolerance, their plasma insulin levels rapidly shoot up - this represents the first phase insulin release
For patients with type 2 diabetes - there is only a curved, small increase in plasma insulin
What are the effects of T2DM on the skeletal muscle?
reduced insulin action causes less uptake of glucose into the skeletal muscle
What are the effects of T2DM on the hepatic glucose production?
hepatic glucose production increases due to a reduction in insulin action and increase in glucagon action
What happens to glucagon levels in T2DM and what is the effect?
Excessive glucagon mediated glucose output - causes an increase in the hepatic glucose production
What is the relationship between insulin resistance and insulin secretion?
Sigmoidal curve - high insulin sensitivity = low insulin secretion
What is the effect of T2DM on the insulin secretion/insulin sensitivity curve
They have “Fallen off the curve” - for a given degree of insulin sensativity, they secrete less insulin
Whole curve shifts inwards to the left
In a hyperglycaemic clamp, what is infused continuously to induce an insulin response?
Glucose - Hyperglycaemic clamp allows for quantification of beta cell sensitivity to glucose
Explain beta-cell function at diagnosis of T2DM.
At the time of diagnosis (t=0), the beta-cell function (%) has a diminished capacity to that prior to diagnosis.
- Insulin production is compromised.
- Homeostasis model can be used to calculate beta-cell function (Index).
Under usual circumstances, does hyperglycaemia associate with ketosis?
NO
What two factors contribute to increased fasting glucose in patients with T2DM?
Decreased glucose disposal and increased hepatic glucose output contributes to increased fasting plasma glucose (FPG) in diabetes mellitus.
In T2DM, what is the excessive amounts of glucose converted into?
Lactate
Insulin insufficiency reduces the rate of what?
Insulin insufficiency reduces the rate at which glucose-6-phosphate is converted into glycogen
What happens to glucose uptake by the adipocytes and monocytes in T2DM?
Reduced uptake by adipocytes and myocytes
What happens to serum triglycerides in Insulin resistance?
Elevation in serum triglycerides