Micro + Macrovascular complications of diabetes

Question 1

What do microvascular complications affect and what are three examples?

Answer 1

Small Vessels: Retinopathy, Nephropathy, Neuropathy (remember pathy)

Question 2

What do macrovascular complications affect and what are three examples?

Answer 2

Large Vessels: Cerebrovascular Disease, Ischaemic Heart Disease, Peripheral Vascular Disease (remember disease)

Question 3

What level of HbA1c proposes a higher risk of microcomplications?

Answer 3

53mmol/mol (7%) (42-48 impaired tolerance // 48+ is diabetes)

Question 4

Effect of hypertension on complication risk

Answer 4

Increases the risk of complications

Question 5

What are 5 factors that can lead to microvascular complications?

Answer 5

Blood pressure, causes endothelial damage
Smoking, causes endothelial dysfunction
Hyperlipidaemia, high cholesterol clogs arteries
Genetics, may develop complications despite good glycemic control
Duration of Diabetes, risk increases with time
Hyperglycaemic Memory (inadequate glucose memory early on), damage from earlier lack of control can affect later life

Question 6

What is the mechanism for damage for microvascular complications?

Answer 6

Risk factors cause formation of free radicals in the endothelium which cause damage by activating inflammatory pathways.
Causes leaky capillaries, releasing exudates which lead to further damage
Causes ischemia due to restricted blood flow

Question 7

What is the problem with detecting diabetic retinopathy?

Answer 7

Early stages are asymptomatic
.: do annual retinal screening

Question 8

What are the three stages of retinopathy?

Answer 8

Background Retinopathy,
Pre-proliferative Retinopathy,
Proliferative Retinopathy

with worsening retinal ischaemia

Question 9

What do soft exudates represent?

Answer 9

Retinal ischaemia

Question 10

What can you see in proliferative retinopathy?

Answer 10

Visible new vessels on retina or optic discs
angiogenesis, new vessels are highly friable and subject to rupturing

Question 11

What is maculopathy?

Answer 11

background retinopathy but in the macula
see hard exudates near macula
(centre of retina used for central vision - like reading)

Question 12

Background retinopathy treatment

Answer 12

Continued annual surveillance
check glycemic control, cholesterol, bp, smoking status

Question 13

Pre-proliferative and proliferative retinopathy treatment

Answer 13

Panretinal photocoagulation
to try and stop angiogenesis, burn the area around retina with a laser

Question 14

How do you treat maculopathy?

Answer 14

Anti-VEGF (Vascular Endothelial Growth Factor) Injections, Grid Photocoagulation

Question 15

What is the disadvantage of panretinal photocoagulation?

Answer 15

Loss of peripheral vision

Question 16

Why should diabetic nephropathy be taken seriously?

Answer 16

Can lead to end-stage kidney failure and increased risk of cardiovascular events (with microalbuminuria)

Question 17

How do you diagnose nephropathy?

Answer 17

Urine screening for protein, using albumin:creatinine ratio (microalbuminuria > 3mg/mmol ,
proteinuria > 30mg/mmol)

Question 18

What is the downside of measuring ACR

Answer 18

False positives common .: must be taken twice to be indicative of microalbuminuria

Question 19

What is the earliest feature of diabetic nephropathy?

Answer 19

Microalbuminuria (>2.5mg/mmol)

Question 20

What is the mechanism for diabetic nephropathy?

Answer 20

Glomerular hypertension can lead to proteinuria (pushes proteins through). This leads to glomerular fibrosis and lower eGFR

Question 21

Renin - Angiotensin system

Answer 21

Angiotensinogen from the liver
Renin from the kidneys causes conversion to angiotensin 1
ACE converts to angiotensin 2
Ang2 is a vasoconstrictor and stimulates zona glomerulosa to produce aldosterone

Question 22

How would you treat diabetic nephropathy?

Answer 22

Block rennin-angiotensin system -> using ACE Inhibitor (-pril) or ARB (Angiotensin receptor blocker, - sartan) EVEN if they are normotensive

Question 23

How should you manage diabetic nephropathy?

Answer 23

Tighter glycaemic control,
Reduce blood pressure (<130/80),
Smoking cessation,
Start SGLT-2 inhibitor (can delay nephropathy)

Question 24

How does diabetic neuropathy happen?

Answer 24

Damage to vasa nervosum (blood vessels that supply nerves)

Question 25

What are the risk factors for diabetic neuropathy?

Answer 25

Age,
Smoking,
Height (longer legs = longer nerves),
Duration of Diabetes
Poor Glycaemic Control

Question 26

Where are the effects of diabetic neuropathy most common?

Answer 26

Feet (can be hands as well) - as these are the longest nerves

Question 27

What is a common problem due to diabetic neuropathy?

Answer 27

Foot ulceration

Question 28

Why is there an increase of foot ulceration?

Answer 28

Reduced sensation (peripheral neuropathy)
Poor vascular supply (peripheral vascular disease)

Question 29

What do you look for in an annual foot check?

Answer 29

Foot deformity and ulceration
Sensation (using microfilament)
Foot pulses, poor blood flow means delayed healing

Question 30

How do you manage diabetic foot with ulceration?

Answer 30

Antibiotics, Orthotic Footwear, Amputation

Question 31

What are two other neuropathies from diabetes?

Answer 31

Mononeuropathy,
Autonomic Neuropathy

Question 32

What does mononeuropathy affect and what signs do they see?

Answer 32

Occulomotor - leads to 3rd nerve palsy (eyes down and out)

Question 33

What does autonomic neuropathy affect and what signs do they have?

Answer 33

Damage to sympathetic and parasympathetic nerves of GI and Cardiovascular
GI - delayed gastric emptying, nausea, nocturnal diarrhoea Cardiovascular - postural hypotension, sudden cardiac death

Question 34

What are the non-modifiable risk factors for macrovascular disease?

Answer 34

Age, Birth Weight, Genes

Question 35

What are the modifiable risk factors for macrovascular disease?

Answer 35

Dyslipidaemia, Hypertension, Smoking, Diabetes Mellitus, Central Obesity

Question 36

Managing cardiovascular risk

Answer 36

Smoking cessation
Reduce blood pressure
lipid profile
weight
annual urine microalbuminuria screen