T2DM (Type 2 Diabetes Mellitus)

Exam Cram

• Type 2 diabetes is a chronic metabolic disorder of insulin resistance

• Diagnosis: symptoms + hyperglycaemia measured twice (HbA1c > 48)

• Complication: HHS, hypoglycaemia (iatrogenic), infections

  • • Microvascular: diabetic nephropathy, peripheral neuropathy, diabetic eye disease

    • Macrovascular: cardiovascular & stroke disease

• Management

  • • Antiglycaemic: metformin -> assortment -> insulin

    • Monitor for complications, diet & medication compliance

Outline

Assessment

History

• Overweight, > 40yrs

• Lethargy, polydipsia

• Can by asymptomatic

Examination

• Increased BMI

• Peripheral neuropathy

• Reduced visual acuity

Investigations

• Insulin: raised

• C-peptide: raised

• Blood glucose raised

• HbA1c raised

Diagnosis

Diagnostic criteria (adults): biochemical + symptoms

Symptoms

• Polyuria, polydipsia, blurred vision, weight loss, recurrent infections, tiredness

• Acanthosis nigricans, HHS

Biochemical 

• HbA1c > 48 (6.5%)

• Fasting blood glucose > 7.0

• Random blood glucose > 11.1

Absence of symptoms diagnosis requires repeating blood glucose levels prior to diagnosis. Caution with HbA1c in haemoglobinopathies and CKD. 

Differentials

• Polyuria/ polydipsia: diabetes insipidus, haemochromatosis, hypercalcaemia

• Type 1 Diabetes, LADA, MODY

• Metabolic syndrome: obesity, HTN, PCOS, IBS, dyslipidemia

Severity

Dictated by HbA1c

• 43-48: pre-diabetes

• 48-53: well controlled

• 53-58: moderate control

• > 58: poor control 

Management

1. Metformin

2. Either

   1. 1. SGLT-2 inhibitor if  signs of CHF or CKD

      2. Or DPPV inhibitor if signs of CKD, 

3. DPPV inh & SGLT-2 inh (depending upon comorbidities)

4. Gliclazide

5. Insulin

Thalidiones not used due to fluid retention (worsening CHF, common comorbidity) and bladder cancer

GLP-1 agonists can be used as an alternative to DPP4 inhbitors, nil role for both

Anti Hyperglycaemic Drugs

Biguanide

Metformin

Moa

1. Increases insulin sensitivity

2. Reduced hepatic gluconeogenesis, diarrhoea

Side effects

1. Diarrhoea (potentially how it really works, by reducing food absorption)

2. Lactic acidosis (reduced gluconeogenesis)

Cautions

1. Reduce dose to 50% eGFR 30-45 (risk of lactate acidosis)

2. Stop if eGFR < 30

Sulphonylureas

Gliclazide

Increases pancreatic insulin, independently to glucose

SE: hypoglycaemia and weight gain (from increased insulin)

CKD: stop if eGFR < 30, half dose if eGFR < 45

SGLT-2 Inhibitors

Dapagliflozin, empagliflozin

SGLT 2 reabsorbs sugar in the proximal convoluted tubule in the nephron

SGLT-2 lower blood sugar by increasing glyosuria, more sugar to be excreted in the urine 

SLGT-2 have benefits in CHF and CKD

Incretin mimetics

DDPV-4 Inhibitors: Sitagliptin, saxagliptin, linagliptin, alogliptin

GLP-1 Agonists: Dulaglutide, exenatide, liraglutide, ozempic

Incretin lowers blood glucose

GLP increases incretin and DDPV inhibits incretin

GLP-1 agonists have a beneficial effect on CKD and weight, nil effect on CHF

*

Thalididiones

Moa: PPAR gamma agonist- increases insulin sensitivity

Drugs: pioglitazone

SE: fluid overload, bladder cancer

Rarely used because many diabetics have CHF and are overweight so the side effects are poorly tolerated

Alpha Glucosidase Inhibitor

Drug: acarbose

Moa: reduces GI absorption of carbohydrates

Side effects: GI upset

Rarely used due to GI upset

Gestational Diabetes

Raised blood glucose:

1. Two weeks of dietary measures

2. Metformin

3. Gliclazide

References

NICE Guidelines

https://cks.nice.org.uk/topics/diabetes-type-2/diagnosis/diagnosis-in-adults/

Page written in 2024.