Diabetes mellitus Flashcards
When blood glucose is too high (hyperglycaemia) for long periods of times (years)
over the years leads to damage of the small and large blood vessels causing premature death from cardiovascular disease
DM and kidney disease
1/4 diabetics develop kidney disease
how much of NHS budget spent on diabetes
around 10%
DM is the leading cause of
blindness in working age
DM is the most common cause of
traumatic lower limb amputation
(15% life time risk of amputation)
70% of DM patients die due to
CVD
life expectancy reduced on average by
5 to 15 years in T1 DM and 5 to 10 in T2DM
When you eat, your body breaks food down into glucose. Glucose is a type if sugar that is your body’s main energy source.
As blood glucose rises……
signals to the pancreas beta cells to release insulin
insulin has its affect on which cells
skeletal muscle, liver and fat
how does insulin decrease blood glucose
binds to insulin receptors which triggers the transcription and translocation of GLUT4 to the surface of the cell allowing glucose to enter
pancreatic islet cells
In Dm why does glucose rise
- Inability to produce insulin due to beta cell failure
- Insulin production adequate but insulin resistance prevents insulin working effectively and invariably linked to obesity
type 1 diabetes
Due to autoimmune beta cell destruction
- Beta cells- secrete insulin
- Autoantibodies made are directed against the beta cells and insulin producing cells destroyed
- Mostly genetic predisposition
in T1DM the pancrease does not produce enough insulin this is called an
absolute insulin deficiency (immune destruction of beta cells)
Type 2 DM
Pancreas may not produce enough insulin or cells do not use insulin properly (resistance)
- relative insulin deficiency
how does DM present
hyperglycaemia
inadequare energy utilisation
hyperglycaemia will cause
- polyuria
- polydipsia
- blurry vision
- urogenital infections- thrush
Symptoms of inadequate energy utilisation
- tiredness
- weakness
- lethargy
- weight loss
severity of DM symptoms will depend on
the rate of rise of blood glucose as well as the absolute levels of glucose achieved
tests use to diagnose diabetes
- Fasting glucose
- Oral glucose tolerance test
- HbA1c
HbA1c
measure of glucose control over the last few months (number of glucose molecules attached to HbA1C – over 3 months because glucose have a lifespan of 120 days)
- best measure doesnt need fasting and not reactive to recent changes in diet
if asymptomatic
need two abnormal blood tests
(probably first discovered during routine screening)
if symptomatic
1 abnormal test adequate for diagnosis
treatment of T!DM
- Exogenous insulin
- Giving by subcutaneous injections several times per day
Lessons from bariatric surgery and very low calorie diets
Restrictive low calorie diets seem to help reduce liver fat and help revert diabetes
MRI scan of the liver showing high levels of fat in green (left) and a sharp decrease in liver fat achieved using a low-calorie diet (right)
chronic macrovascular complications of
- Cerebrovascular
- Cardiovascular e.g. coronary A
- Peripheral vascular disease (stroke, heart attack, intermittent claudication, gangrene)
retinopathy
blindness
nephropathy
need for renal replacement therapy
Thickened basement membrane of the glomerulus- filtering function of tissue is damaged – loss of protein (albumin) in urine
