macrovascular & microvascular complications Flashcards
(28 cards)
What are the microvascular complications?
Retinopathy, nephropathy, neuropathy
What are the macrovascular complications?
Ischaemic heart disease, cerebrovascular disease, peripheral vascular disease
Relationship between glycaemic control and risk of vascular complications? What is target HbA1c to reduce these complications?
Worse glycaemic control worse risk. Target HbA1C is 53mmol/L to reduce complications
what other factors are linked to vascular complications?
Duration of diabetes, dyslipidaemia, hypertension, hyperglycaemic memory, smoking
What is the mechanism of microvascular complications?
Combination of hyperglycaemia and tendency towards high cholesterol paired with hypoxia to the vessels leads to pro-inflammatory state - inflammation causes damage of small vessels. Leads to hypoxia of tissues and leaky vessels.
What does diabetic retinopathy cause? Early stages? What do we need to do?
Causes vision loss. Early stages asymptomatic. Annual retinal screening.
what is seen in background retinopathy?
Hard exudates. Microaneurysms and blot haemorrhages.
what is seen in pre-proliferative retinopathy?
More extensive haemorrhages and increased white spots (cotton wool spots/soft exudates) that represent ischaemia
what is seen in proliferative retinopathy?
New vessels formed that are easily friable and bleed easily. Haemorrhages too.
what is seen in diabetic maculopathy?
Hard exudates/oedema near macula. Same as background retinopathy but near macula, this can threaten vision
What is treatment for each stage of retinopathy?
- Background retinopathy no treatment but annual retinal screening.
- Pre-proliferative retinopathy early pan-retinal photocoagulation (burns through retinal haemorrhages to prevent further damage and new vessel formation).
- Proliferative retinopathy - pan-retinal photocoagulation. 4. maculopathy - for oedema - anti VEGF injections into eye to stop inflammatory cascade. Grid photocoagulation
What is diabetic nephropathy associated with?
End-stage renal disease requiring dialysis and CV disease
How is diagnosis of diabetic nephropathy made?
Urine test for proteinuria - ACR albumin creatinine ratio. Microalbuminuria >2.5 ACR, proteinuria >30, nephrotic range losing 3000mg/24 hours (huge amounts of proteinuria).
-Diagnosis needs progressive albuminuria, hypertension, deranged renal function (eGFR)> in advanced stage will see peripheral oedema.
What is the mechanism underpinning diabetic nephropathy?
Combination of hyperglycaemia and hypertension damages the glomerulus leading to reduction in eGFR. Renin-angiotensin system driving vasoconstriction is in overdrive (thus need ACE inhibitors or ARBS)
What to do when microalbuminuria?
Start ACE inhibitor or ARB
Why not give ARBS and ACEi together?
no extra benefit. can interfere with potassium
Effects of microalbuminuria?
Increased risk of stroke, MI, CV disease
Management of diabetic nephropathy?
Tighter glycaemic control, stop smoking, aim for blood pressure (130/80), consider starting SGLT-2 inhibitor. Ace/arb if microalbuminuria
What is diabetic neuropathy (peripheral)? Why can it cause damage?
Damage of the peripheral nerves. Supplied by small blood vessels - vasa nevorum - get blocked during neuropathy. Can lead to loss of sensation peripherally especially at legs, leading to damage
Risk factors of diabetic neuropathy?
Hyperglycaemia, dyslipidaemia, smoking, height (longer nerves) presence of diabetic retinopathy
Why feet more commonly? What distribution?
Longer nerves in legs. Glove and stocking distribution
Why diabetic foot ulceration?
Reduced sensation in the feet predisposes them to damage - get hurt and cannot feel it
What is checked at annual foot check?
Deformity, ulceration, sensation and foot pulses
Management of diabetic neuropathy?
Regular inspection, good footwear, avoid being barefoot. If ulcer, foot clinic, offloading period for rest, often cant heal because of peripheral vascular disease so vascular surgeon can do re-vascularisation, antibiotics if infected, amputation
