Type 2 Diabetes Mellitus

Question 1

Define Diabetes Mellitus Type 2

Answer 1

Chronic syndrome of impaired carbohydrate, protein and fat metabolism characterised by increased peripheral target-tissue resistance to insulin action, impaired insulin secretion and a raised hepatic glucose output

Question 2

What is the aetiology of T2DM

Answer 2

Insulin resistance + impaired secretion → hyperglycaemia
Insulin resistance primarily affects the liver, muscle and adipocytes
BG genetic predisposition (90% MZ twin concordance)
Secondary to
- pancreatic disease: chronic pancreatitis, haemochromatosis, pancreatic cancer, iatrogenic
- Endocrine: Cushing’s, acromegaly, phaeos, glucagonoma
- Drugs e.g. steroids, antipsychotics, protease inhibitors

Question 3

What are the risk factors for T2DM

Answer 3

Strong family history
Obesity or overweight
Older age
Physical inactivity
Black or Asian ethnicity
Hypertension
Lipid disorders (hypercholesterolaemia)

Question 4

What are the symptoms of T2DM

Answer 4

Asymptomatic
Tiredness, fatigue
Blurred vision
Polyuria, polydipsia, nocturia
Paraesthesia
Polyphagia
Increased risk of infections: foot ulcers, candidiasis, balanitis, pruritus vulvae, cellulitis, UTIs

Question 5

What are the signs of T2DM on examination

Answer 5

BMI: raised
BP: ?HTN
Skin:
- Acanthosis nigricans (Light brown-black marking on the neck, on the axillar or on the groin)
- Necrobiosis lipodica (well-demarcated plaques on shins/arms with shiny atrophic surface and red-brown edges)
- Granuloma annulare (flesh-coloured papules coalescing in rings on hands and fingers)
- Diabetic dermopathy (depressed pigmented scars on shins)
Diabetic foot: dry skin, reduced SC tissue corns, calluses, ulceration, gangrene, Charcot’s arthropathy, reduced/absent foot pulses

Question 6

What investigations should be done for T2DM

Answer 6

Bedside: BM, urine dip, urinary ketones (+ve = T1DM, -ve = T2), ECG, fundoscopy
Bloods
- Random plasma glucose: >11
- Fasting plasma glucose: >6.9
- HbA1c: >48 (glucose for 2-3 months)
– <7 = impaired glucose tolerance
- OGTT >11.1 (impaired = 7.9-11.1) - for borderline/GDM
- Plasma ketones: negative (diff from T1)
- Fasting C peptide: >1 (diff from T1)
- Auto-immune markers: -ve
- Fasting lipid: often normal, may be raised
- Renal function

Question 7

What is the management for T2DM

Answer 7

1. Lifestyle changes: Personalised self-management programme, usually developed by a diabetes education nurse or nutritionist.
2. Glycaemic management
3. Monitoring

Question 8

What are the lifestyle changes recommended to those with T2DM

Answer 8

Limiting caloric intake
High fibre, low glycaemic index carbs
Low-fat dairy products and oily fish
Moderate physical activity (improve control, weight maintenance, CV risk reduction): 3-4 aerobic activities per week
Weight loss
Reduce alcohol intake
Smoking cessation

Question 9

What are the options for glycaemic control in T2DM

Answer 9

After lifestyle advice → HbA1c remains >48 →
1. Metformin
- IF high-risk/established CVD/CHF/QRISK >10%→ add SGLT-2 inhibitor
- If not tolerated → switch to modified release
2. Titrate up metformin + encourage lifestyle changes

Only add a second drug if >58
3. Metformin + DPP4i, pioglitazone, SU, SGLTI-2i
4. Metformin + 2 glycaemic control drugs OR insulin
5. Switch one drug for a GLP-1 mimetic

Question 10

Give an example of a drug from each class for diabetic control

Answer 10

Biguanide - metformin
Sulphonylurea - glibenclamide
Thiazolidinedione - pioglitazone
DPP4-inhibitor - gliptin (PO)
SGLT-2 inhibitors - empagliflozin
GLP-1 analogues - liraglutide, exenatide (SC injection within 60mins BEFORE morning and evening meals)

PCSK-9 inhibitors - evolocumab

Question 11

What monitoring should be done for T2DM

Answer 11

Hypertension
Dyslipidaemia
Albuminuria (Kidney disease) via ACR
Retinopathy (refer)
Periodontitis

Question 12

What are the complications of T2DM

Answer 12

Hyperosmolar hyperglycaemic state (HHS)
Microvascular: retinopathy, neuropathy, nephropathy
Macrovascular:
Diabetic foot

Question 13

What are the HbA1c targets for those with T2DM

Answer 13

HbA1c should be checked every 3-6 months until stable, then 6 monthly

Lifestyle only: 48 (6.5%)
Lifestyle + metformin: 48 (6.5%)
Any drug that can cause hypoglycaemia: 53 (7/0%)
Already on monotherapy but HbA1c has risen to 58: 52 (7/0%)

Question 14

What are the sick day rules for type 2 diabetes

Answer 14

Temporarily stop some oral hypoglycaemics during an acute illness
medication may be restarted once the person is feeling better and eating and drinking for 24-48 hours

metformin: stop treatment if there is a risk of dehydration, to reduce the risk of lactic acidosis.
SGLT-2: stop in DKA
GLP-1: stop if risk of dehydration

Question 15

Side effects of T2DM medication

Answer 15

Metformin
- GI disturbance e.g. N&V, diarrhoea, pain
+ weight loss

Sulphonylureas (gliclazide/glibenclamide):
- Hypoglycaemia
- Weight gain
- GI disturbance (N&V)
- SJS

DPP4i (gliptins)
+ weight neutral

Thiazolidinediones (pioglitazone)
- Weight gain
- CI in heart failure and bladder cancer

SGLT-2i (Empagliflozin)
- Fournier’s gangrene (necrotising fasciitis of the genitalia)
- Recurrent thrush
- CI in active foot disease
+ weight loss

GLP-1 analogues (liraglutide)
+ weight loss