The Aetiology and Treatment of Type 2 Diabetes Mellitus Flashcards
What tests are performed to diagnose diabetes and what are the defining values?
Fasting Blood Glucose: Normal < 6 Impaired Fasting Glucose = 6-7 Diabetes > 7 Glucose Tolerance Test (2 hr measurement) Normal < 7.8 Impaired Glucose Tolerance = 7.8-11.1 Diabetes > 11.1
State three factors that influence the pathophysiology of T2DM.
Genetics
Intrauterine environment
Adult environment
How is the intrauterine environment important in the pathogenesis of T2DM?
There will be epigenetic changes that take place in utero, which affect blood glucose control in the future
What is MODY?
Mature onset diabetes of the young (8 types)
It is autosomal dominant
Ineffective pancreatic beta cell insulin production
Caused by mutations of transcription factor genes (glucokinase gene)
Positive family history with NO obesity
What can modulate insulin resistance through adult life beforesomeone develops diabetes?
Adipocytokines
What type of babies are more likely to develop T2DM in later life?
Small babies (low birth weight) This is due to intrauterine growth restriction
How does insulin resistance lead to hypertension?
Insulin resistance leads to a compensatory hyperinsulinaemia
Though the insulin doesn’t affect the glycaemic control pathway, it stimulates the mitogenic pathway causing smooth muscle hypertrophy –> high blood pressure
What eventually happens to the beta cells in T2DM?
Insulin resistance damages the beta cells and eventually results in beta cell failure
Describe how beta cell reserve and insulin resistance change with age.
Beta cell reserve decreases with age and insulin resistance increases
Describe the presentation of a typical patient with T2DM.
Obese (80%)
Insulin resistance and insulin secretion deficit
Hyperglycaemia and dyslipidaemia
Acute and chronic complications
What dietary changes can someone with T2DM make to reduce the effect of the missing first phase insulin release?
Complex carbohydrates – release glucose more slowly
Describe glucose clearance and hepatic glucose output in T2DM.
Glucose clearance is decreased
Hepatic glucose output is increased
What normally happens to insulin secretion as insulin resistance increases?
Insulin secretion increases to compensate for the increased insulin resistance
Which adipocytes are particularly marked for breakdown of triglycerides?
Omental adipocytes (this is why omental fat correlates with risk of heart disease)
What happens to fatty acids when they go into the liver?
They cannot be used to make glucose so they are converted to very low-density lipoproteins (VLDLs), which are highly atherogenic