Macrovascular complications Flashcards
(40 cards)
Who gets macrovascular disease?
Occurs in people with and without diabetes. Only thing varying is the extent to which it occurs and how early.
What is macrovascular disease? (examples)
Macrovascular Disease is a systemic disease and is commonly present in multiple arterial beds.
- Early widespread atherosclerosis
- Ischaemic heart disease (e.g. myocardial infarction)
- Cerebrovascular disease (e.g. stroke)
- Renal artery stenosis (causes hypertension and renal failure)
- Peripheral vascular disease
What is the sequence of endothelial dysfunction?
- initial lesion (macrophages and foam cells)
- fatty streak (intracellular lipid accumulates)
- intermediate lesions (+extracellular lipid)
- atheroma (core of extracellular lipid)
- fibroatheroma (fibrotic/calcific layers)
- complicated lesions which can thrombose/haemorrhage
What factors are associated with arterial damage?
- hyperglycemia
- hypertension
- low HDL
- High waist circumference
- Insulin resistance
What are the initial stages of arterial damage associated with?
insulin resistance, lipid accumulation and blood pressure
What is smooth muscle hypertrophy in vessels associated with?
In which cases is thrombosis most likely to occur?
Insulin resistance, and is a feature of atheroma. Lesions then develop collagen, and can go on to thrombose on top of the lesion, and block the vessel. Thrombosis is more likely to occur in insulin resistant patients.
What is the relationship between hyperglycaemia and life expectancy?
- Hyperglycaemia is associated with significantly reduced life expectancy
- Diabetics are expected to die earlier when age of diagnosis is earlier
- This is related to the length for which someone has had diabetes
Relationship between insulin resistance and MI/life expectancy
If insulin levels are low (the patient is insulin sensitive), they are likely to live longer. Subjects with insulin resistance have a significantly increased chance of heart attack (age and sex adjusted).
Is diabetes a progressive disease?
YES
What is the difference between microvascular and macrovascular disease in terms of morbidity and mortality?
Microvascular disease causes morbidity; macrovascular disease causes morbidity and mortality.
In diabetic patients, how many die from MI, how many have strokes and malignancy?
- 60% from myocardial infarction
- 25% for stroke (but they are having strokes younger than the general population)
- Malignancy is reduced as they aren’t living long enough to develop cancer
Why is ischaemic heart disease treated strictly in diabetics?
People with diabetes have the same risk of MI and death as those people who have previously had an MI
What is the effect of ethnicity on diabetes?
- In White Caucasians, the coronary heart disease risk was predicted well by Framingham data
- In South Asians, the Framingham data underestimated risk
Framingham risk score - South Asians have a worse mortality for coronary heart disease than white Caucasians.
Ischaemic heart disease in diabetics
- The major cause of morbidity and mortality in diabetes
- The mechanisms are similar with and without diabetes (but in diabetes, it occurs earlier on)
Cerebrovascular disease in diabetes
- Occurs earlier than without diabetes (younger rather than elderly)
- More widespread – has the risk factors of high blood pressure and cholesterol
Peripheral vascular disease in diabetes
- Contributes to diabetic foot problems with neuropathy
- Neuropathy alone can cause diabetic foot problems, but peripheral vascular disease worsens this
Renal artery stenosis in diabetes
- May contribute to high blood pressure (hypertension) and renal failure
- It can permanently damage renal function
How does hyperglycaemia treatment affect risk of cardiovascular disease?
Small effect on risk of cardiovascular disease.
- If you treat glucose intensively, you do slightly reduce coronary artery disease risk
- Intensive glucose control does improve coronary heart disease risk but it does not change mortality much.
- Management of glucose alone does not address vascular risk
What are some modifiable and non-modifiable factors contributing to diabetes?
Non-modifiable factors (age, sex, birth weight, FH and genetic makeup)
Modifiable factors (dyslipidaemia, high blood pressure, smoking, diabetes)
What factors must be addressed to reduce macrovascular disease and death?
All aspects of diabetes. Prevention of macrovascular disease requires aggressive management of multiple risk factors. Insulin resistance before hyperglycaemia itself contributes
What is the role of statins in diabetes?
Giving a statin early on in diabetes has a very significant reduction in the risk of a heart attack or stroke. Practically all people >50 with diabetes should be treated with a statin.
Why are diabetics given antihypertensives?
- To control their blood pressure
- This produces a significant reduction in the risk of having a heart attack, and risk of diabetic retinopathy
What is multi-factorial risk reduction?
Subjects can be intensively treated in terms of weight, exercise, BP, lipids and glucose - many factors
What are the treatment goals in type 2 diabetes?
- Blood glucose lowering therapy –via metformin, sulphonylurea, insulin, etc.
- Blood pressure management – if damage is to kidneys, eyes or cerebrovascular damage, lower considerably (<130/80mmHg) but other targets and lower less (<140/80mmHg)
Constant monitoring - Management of blood lipids –review CV risk annually
