Complications of Diabetes

Question 1

Name some acute complications of T1DM?

Answer 1

Ketoacidosis

Hypoglycaemia.

Question 2

List some chronic microvasuclar complications of T1DM?

Answer 2

Reinopathy
Neuropathy
Nephropathy.

Question 3

List some chronic macrovascular complications of T1DM?

Answer 3

Ischaemic heart disease
Peripheral vascular disease
Cerebrovascular disease.

Question 4

What did the UKPDS and DCCT trails prove?

Answer 4

That intensive glycaemic control can help prevent microvascular disease.

Glycaemic control isnt as important for macrovascular disease - BP, cholesterol and smoking are more important factors.

Question 5

What 2 factors cause microvascular disease?

Answer 5

Capillary damage.

Metabolic damage.

Question 6

What can cause capillary damage?

Answer 6

Hyperglycaemia (small vessels will be structually and functionally abnormal).
Increased blood flow.
Increased capillary pressure.
Thickened and damaged vessel walls.
Endothelial damage (leakage of albumin and other proteins).

Question 7

What causes metabolic damage?

Answer 7

Most tissues need insulin to take up glucose - except retina, kidney and nerves.
Glucose goes across these cell membranes and is metabolised to sorbitol by aldose reductase.
Excessive glucose enters the polyol pathway and sorbitol accumulates, there is less NADPH for cell metabolism and build up of reactive oxygen species and oxidative stress leads to cell damage.

Question 8

Why is microvascular disease not so much of an issue in T2DM?

Answer 8

As patients with T2DM usually die of CV first.

Question 9

Describe the stages of diabetic retinopathy?

Answer 9

1. Hyperglycaemia: damage to small vessel wall and microaneurysms.
2. Dot haemorrhages: When vessel wall is breached.
3. Hard exudates: When protein and fluid is left behind after blood drain away.
4. Cotton wool spots: Micro-infarcts.

LATER STAGES
Damage to veins: Venous budding and blockage of blood supply.

Ischaemia - VEGF and other growth factors cause neovascularisation, proliferative retinopathy and these vessels are weak so prone to bursting causing vitreous haemorrhage. This happens as vessels try to pass blockage.

Fluid not cleared from macular area - macular oedema.

Question 10

How is retinopathy prevented?

Answer 10

Good glycaemic control.
Stop smoking.
Good BP control.
Retinal screening for diabetic patients aged 12+. Taking pictures of the eye.

Question 11

How is retinopathy treated?

Answer 11

Addressing risk factors.
Ophthalmic review;
- Laser new blood vessels.
- VEGF inhibitors to stop new vessels forming.
- Vitrecotomy

Question 12

List the stages of diabetic nephropathy?

Answer 12

1. Renal enlargement and hyperfiltration: so GFR increases. The afferent arteriole vasodilates and there is an increase in glomerular pressure, thickened BM, capillary damage and shear stress on endothelial cells.
2. Microalbuminuria: Tiny traces of albumin that cant be detected on the dipstick. It can be used as an independent CV disease predictor.
3. Macroalbuminuria.
4. End stage renal failure: As there is glomerularsclerosis and destruction.

Question 13

How can nephropathy be prevented/treated?

Answer 13

Screening for microalbuminuria every year from diagnosis.
ACEi/ARB if microabuminuria present to slow progression.
Improve glycaemic control.
CV prevention with statins, smoking reduction.
Refer to renal clinic if eveloped CKD (eGFR <30)

Question 14

List types of diabetic neuropathy?

Answer 14

Peripheral (sensory) neuropathy.
Autonomic neuropathy.
Mononeuritis multiplex.
Diabetic amyotrophy.

Question 15

What causes neuropathy?

Answer 15

Capillary damage occurs to vessels that supply nerves.
Sorbitol can build up and there is often occlusion in the vasa nervorum.
This impairs nervous signalling and impairs both sensory and motor function.

Question 16

What clinical signs are seen in neuropathy?

Answer 16

Decreased vibratory sensation.
Decreased pressure sensation.
Decreased reflexes in knee and ankle.
Loss of proprioception.
Cant sense hot/cold.
Unusual sensitivity when feet are touched.
Decreased proprioception (ability to sense position of feet).
Symptoms such as numbness, prickling and pain.

Can have tissue damage, clawing toes, callus, ulceration.

Question 17

What is the diabetic foot?

Answer 17

Combination of neuropathy and peripheral vascular disease.

Often causes infection, ulcers and ischaemia.

Question 18

How is diabetic foot symptoms prevented?

Answer 18

If low risk (normal sensation and pulses): Annual review. 
Medium risk (neuropathy or absent pulses): Review by podiatrist every 3-6 month. 
High risk (deformities or ulceration): Podiatrist review every 1-3 months.

Question 19

What is Charcot foot?

Answer 19

Numbness (repeated microtrauma and stress fractures) and dysregulated blood flow (bone turnover and fragile bone).

Question 20

Describe features of autonomic neuropathy in different systems?

Answer 20

CV: Postural hypotension.
GU: Erectile dysfunction.
GI: Gustatory sweating or gastroparesis.
MSK: Diabetic myotrophy (proximal neuropathy - thigh/buttock).
Mononeuritis Multiplex: Painful assymetrcal motor and sensory neuropathy (2+ nerves).

Question 21

What would be involved in the annual review for DM?

Answer 21

HbA1c
Cholesterol, HDL and TG
Creatinine
Microalbuminuria

Lifestyle - exercise, diet, smoking.
Drug therapy.
Mental well-being.

Visual acuity.
Retinal screening.
Pedal pulses.
Foot sensations.
BMI.
BP.
Erectile function. 
Contraception.

Question 22

What test should be done in mothers with DM during pregnant?

Answer 22

HbA1c to reduce risk of congenital malformations.

Question 23

What does good glycaemic control during pregnancy help prevent?

Answer 23

Macrosomnia.

Question 24

What is HbA1C?

Answer 24

Glycosylated Hb.
This develops when Hb joins with glucose.
Takes 3 months to change so when measuring its usually 3 month checks.