18. Macrovascular complications Flashcards
what is the difference between macrovascular disease in people with diabetes and in people without?
- the extent to which it occurs in all vascular beds
- how much earlier it occurs
give some examples of macrovascular disease
- early widespread atherosclerosis
- ischaemic heart disease (MI)
- cerebrovascular disease (e.g. stroke)
- renal artery stenosis
- peripheral vascular disease
what things are associated with artery damage?
- elevated glucose affects atheroma production
- low levels of HDL affect atheroma production
- hypertension
- large waist circumference is associated with ischaemic heart disease
how does macrovascular disease develop?
the initial arterial lesions and fatty streaks are a result of insulin resistance, lipid accumulation and BP damaging arteries. these develop collagen and can go on to thrombose on top of the lesion and block the vessel.
why is diabetes called a progressive disorder?
it gets worse over time
how is the risk for micro and macrovascular disease different in patients with T2DM?
- as glucose enters a diabetic range microvascular disease risk shoots up
- the risk of macrovascular disease is more proportional to the increase in glucose
describe ischaemic heart disease
- major cause of morbidity and mortality in diabetes
- occurs earlier on with diabetes
describe cerebrovascular disease
- occurs earlier on with diabetes (younger individuals)
- more widespread
describe peripheral vascular disease
- worsens diabetic foot problems with neuropathy
describe renal artery stenosis
- may contribute to high BP and renal failure
- can permanently damage renal function
what is the problem with targeting hyperglycaemia alone in treatment of diabetes?
treatment has little effect on increased risk of CVD
what factors need to be modified to reduce the risk of macrovascular disease?
- dyslipidaemia
- high BP
- smoking
- diabetes
what is the recommended treatment for diabetes to reduce macrovascular disease risk?
statins - giving a statin early on in diabetes has a very significant reduction in the risk of a heart attack or stroke
what is canakinumab?
- a new drug which reduces inflammation without affecting lipids
- monoclonal antibody that targets IL1-b
- treatments result in reduced HBA1C and lower risk of recurrent cardiovascular events
what % of NHS bed occupancy is due to diabetes? what % of cases are foot disease?
- 10%
- 50% are cases of foot disease
what is the pathway to foot ulceration?
- sensory neuropathy
- motor neuropathy
- limited joint mobility
- autonomic neuropathy
- peripheral vascular disease
- trauma - repeated minor/discrete episode
- reduced resistance to infection (athlete’s foot)
- other diabetic complications (e.g. retinopathy = patients stubbing their foot as they walk)
what is angiopathy?
extensive atheroma blocking arteries and preventing blood from reaching the feet properly
describe the neuropathic foot
numb, warm, dry, palpable foot pulses, ulcers at points of high pressure loading
describe the ischaemic foot
cold, pulseless, ulcers at foot margins
describe the neuro-ischaemic foot
numb, cold, dry, pulseless, ulcers at points of high pressure loading and at foot margins
how is the foot of a diabetic person assessed?
APPEARANCE - deformity or callus?
FEEL - temperature? dry?
FOOT PULSES - dosalis pedis pulse? posterial tibial pulse?
NEUROPATHY - vibration sensation? temperature? ankle jerk reflex? fine touch sensation?
what is the preventative management for diabetic foot?
- control diabetes
- inspect feet daily
- have feet measured when buying shoes
- buy shoes with laces and square toe box
- inspect side of shoes for foreign objects
- cut nails straight across
- care with heat
- never walk barefoot
how is foot ulceration managed?
- relief of pressure: bed rest, redistribution of pressure/total contact cast
- antibiotics (possibly long term)
- debridement (remove dead tissue and callous tissue)
- revascularisation: angioplasty, arterial bypass surgery
- amputation
what is charcot and how can it be investigated?
inflammation in particular bones
can be investigated with MRI because ulceration and infection can be seen
