Macrovascular complications and Diabetic Neuropathy of the Foot Flashcards
what are the diseases associated in macrovascular disease?
- early widespread atherosclerosis
- IHD
- cerebrovascular disease
- peripheral vascular disease
stages of atheroma formation
- initial lesion with macrophages creating foam cells
- fatty streak with intracellular lipids
- intermediate with extracellular lipids
- atheroma where a core of lipids has formed (clinically significant from this point on)
- fibroatheroma, the atheroma is fibrotic with calcific layers
- complication stage with surface defect and thrombosis
what is associated with significantly reduced life expectancy?
hyperglycaemia (the earlier the presentation, the shorter the life ex)
how do women and men with diabetes compare in atheroma formation?
women lose the protection of being a woman when they have diabetes when developing atheroma
they suffer more than men so the relative risk is much worse for them than men
difference in effects of microvascular and macrovascular disease
micro causes morbidity
macro causes morbidity and mortality
what is the biggest cause of mortality in diabetics?
IHD
more than in the general population
why does malignancy reduce as a cause of death in diabetics?
many diabetes die before cancer can manifest
what is the MI risk in diabetics compared to non-diabetics?
diabetes who have never had an MI have a greater chance of an MI than non-diabetics who have had an MI before
what do diabetics who look well tend to have?
IHD
what is the Framingham risk score?
Framingham risk score
– gender-specific algorithm to estimate 10-year cardiovascular event risk.
which ethnicity have a worse mortality for CHD?
South Asians
cerebrovasc disease in diabetics?
present earlier
more widespread
uncommon in people younger than 60
what does peripheral vasc disease in diabetics lead to?
leads to diabetic foot problems
what does renal artery stenosis contribute to?
contributes to hypertension
is treatment of hyperglycaemia effective in reducing CVD risk?
hyperglycaemia treatment alone is not enough and has a minor effect on reducing risk of CVD
intensive glucose control improves CHD but does not change mortality much
risk factors of macrovascular disease (non-modifiable)
age sex birth weight FH genes
risk factors of macrovascular disease (modifiable)
dyslipidaemia
hypertension
smoking
diabetes
what two factors need management to prevent complications in T2DM
BP and cholesterol
what drug can help significantly reduce macrovascular disease risk?
statins
examples of treatment for reducing blood glucose
metformin
sulphonylureas
insulin
what is the blood pressure management target?
<130/80 when there is damage to kidneys, eyes or cerebrovasculature
otherwise <140/80
needs constant monitoring
how is lipids management monitored?
CV risk analysed annually
risk factors of IHD
- fasting glucose > 6mmol/L
- waist circumference (men >102, women >88)
- insulin resistance
- hypertension
- low HDL
what increase is proportional to the risk of retinopathy?
increasing HbA1c
what is canakinumab?
reduces inflammation
decreased lipids
for damaged arteries
targets IL-1beta
what complications of diabetes predispose you to diabetic foot disease?
neuropathy (sensory, motor and autonomic)
peripheral vascular disease
prevalence
- of DFN in diabetics
- current/past foot ulcerations
2-3%
5-7%
risk of amputation in foot ulcerations
60x higher in diabetics
10% of NHS bed occupancy due to diabetes related foot problems (50% with foot disease)
how can sensory function be tested?
monofilament
10g pressure applied when monofilament bends
what are the 8 ways that can lead to foot ulceration?
1) Sensory neuropathy – cannot feel monofilament – ulcers due to abnormal pressures.
2) Motor neuropathy – imbalance of extensors/flexors so foot is abnormal shape – ulcers due to abnormal pressures.
3) Limited join mobility – causes joint immobility and cannot put hands flat against each other.
4) Autonomic neuropathy – no sweating so skin dries out and you get ulcers.
5) Peripheral vascular disease – blood flow is compromised to the lower limbs.
6) Trauma – repeated or minor episodes.
7) Reduced resistance to infection.
8) Other – diabetic complications (e.g. retinopathy).
how is a neuropathic foot described after examination?
numb warm dry palpable foot pulses ulcers at points of pressure
how is an ischaemic foot described after examination?
cold
pulseless
ulcers at foot margins
what are the features of a neuropathic foot?
numb warm dry pulseless ulcers at points of pressures and foot margins
what factors must be assessed in foot examination?
- appearance (callus, deformity)
- touch/feel (hot, dry)
- foot pulses (dorsalis pedis, posterior tibial)
- neuropathy (vibration, fine touch)
- vibration, temperature, ankle jerk, fine touch
where on the foot can pressure often increase?
great toe metatarsal head (50% of foot lacerations occur here)
what must be managed in diabetics?
o Hyperglycaemia. o Hypertension. o Dyslipidaemia. o Stop smoking. o Education.
what are the preventive measures against diabetic neuropathy of the foot?
o Controlling diabetes: Inspecting feet daily.
o Have feet measured for shoes :Buying shoes with laces and square toe box.
o Attend chiropodist: Cut nails straight across.
o Take care when feet get hot: Never walk barefoot.
how is foot ulceration managed?
Relief of pressure – bed rest and redistribution of pressure.
Antibiotics – possibly long-term.
Debridement.
Re-vascularisation – angioplasty or arterial bypass surgery.
Amputation.
what causes dryness in feet?
autonomic control of sweat glands lost
what causes hand disorders in T2DM?
inability to flatten the palm due to glycosylated tendons limiting joint motility
why do ischaemic feet feel cold?
poor blood supply
what is Charcot Foot?
abnormal disorientation of bones in feet which is painful to a non-diabetic but not painful to a diabetic due to sensory neuropathy
there is a destruction of joints
what causes the deformity of Charcot ?
due to loss of joint-position sense
this abnormal shape predisposes the foot to ulceration which then further predisposes the foot to osteomyelitis
what is osteomyelitis?
bone infection
osteomyelitis vs charcot
osteomyelitis: infection
- hot red foot with ulceration
- forefoot and hind foot issues
Charcot:bone issue
- hot red foot without ulceration
- mid foot issues
