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This is a clinician-written, evidence-based summary aligned to the 2026 MLA Content Map. It is intended for medical students and junior doctors preparing for the UKMLA. Always cross-reference with NICE guidance, local protocols, and clinical judgement.
The Bottom Line
- Diagnosis: HbA1c ≥48 mmol/mol (6.5%) on two occasions (or once if symptomatic), or fasting glucose ≥7.0 mmol/L, or random glucose ≥11.1 + symptoms
- First-line: metformin (titrate to 2 g/day). HbA1c target: 48 mmol/mol (individualise for frail/elderly)
- If metformin insufficient: add SGLT2 inhibitor (especially if CVD or HF), DPP-4 inhibitor, sulfonylurea, or pioglitazone
- SGLT2 inhibitors (dapagliflozin, empagliflozin) have proven cardiovascular and renal benefits — increasingly second-line
- GLP-1 receptor agonists (semaglutide, liraglutide): if BMI ≥35 + specific criteria, or if triple oral therapy fails
- Screen for complications: annual eye screening, urine ACR, foot checks, BP, lipids
Overview
Type 2 diabetes is a metabolic disorder characterised by chronic hyperglycaemia resulting from insulin resistance in peripheral tissues and a progressive decline in pancreatic beta-cell function. It accounts for >90% of all diabetes cases. Unlike type 1, it is not autoimmune, and patients typically produce insulin but cannot utilise it effectively. The disease is strongly associated with obesity, physical inactivity, and genetic predisposition. Long-term complications arise from chronic hyperglycaemia affecting microvascular (retinopathy, nephropathy, neuropathy) and macrovascular (CVD, stroke, PVD) beds.
Epidemiology
Approximately 4.3 million people in the UK are diagnosed with diabetes, with T2DM accounting for ~90%. An estimated further 850,000 are undiagnosed. Prevalence is rising due to obesity. Risk factors: obesity (especially central), physical inactivity, family history, ethnicity (South Asian, Black African/Caribbean — 2–4× higher risk), age >40 (>25 in high-risk ethnic groups), gestational diabetes history, PCOS, and socioeconomic deprivation. T2DM is increasingly diagnosed in adolescents and young adults due to rising childhood obesity.
Clinical Features
Symptoms
May be asymptomatic — often detected on routine blood tests or screening
Polyuria and polydipsia (osmotic diuresis from hyperglycaemia)
Fatigue
Blurred vision (glucose-related lens swelling)
Recurrent infections (UTI, candidiasis, skin infections)
Slow wound healing
Weight loss (less common than T1DM — suggests significant insulin deficiency)
Symptoms of complications at presentation (neuropathy, foot ulcer, visual loss)
Signs
Often overweight or obese (BMI ≥25, or ≥23 in South Asian)
Acanthosis nigricans (velvety hyperpigmented skin in flexures — marker of insulin resistance)
Signs of complications: diabetic retinopathy on fundoscopy, peripheral neuropathy (reduced sensation), foot ulceration
Hypertension (frequently coexistent)
Investigations
First-line
HbA1c≥48 mmol/mol (6.5%) confirms diabetes. Repeat to confirm if asymptomatic. Target: 48 mmol/mol (53 if on drugs causing hypo, e.g. SU/insulin)
Fasting plasma glucose≥7.0 mmol/L on two occasions. Random glucose ≥11.1 with symptoms also diagnostic
Second-line
Lipid profileTotal cholesterol, HDL, LDL, triglycerides — dyslipidaemia is common
U&Es + eGFRBaseline renal function — important before starting metformin and SGLT2i
Urine ACRScreen for diabetic nephropathy — annually from diagnosis
Retinal screeningDigital retinal photography — annually from diagnosis
Foot assessmentAnnual structured foot check — monofilament, pulses, deformity
Specialist
C-peptide + GAD/IA2 antibodiesIf diagnostic uncertainty (thin patient, young age, rapid insulin requirement) — distinguish T2DM from LADA/T1DM
1
Lifestyle + metformin (first-line)
- Structured education (DESMOND programme)
- Dietary modification: Mediterranean-style, reduce refined carbohydrates
- Physical activity: ≥150 min/week moderate intensity
- Weight management: target ≥5% weight loss
- Metformin 500 mg OD → titrate to 2 g/day over weeks. Use modified-release if GI intolerant
- HbA1c target: 48 mmol/mol; review at 3–6 months
2
Dual therapy (if HbA1c above target on metformin alone)
- Add one of: SGLT2 inhibitor, DPP-4 inhibitor, sulfonylurea, pioglitazone
- SGLT2i (dapagliflozin, empagliflozin) preferred if established CVD, HF, or CKD — proven cardiorenal benefit
- SU (gliclazide) if rapid glucose lowering needed — risk of hypoglycaemia and weight gain
- DPP-4i (sitagliptin) — weight-neutral, well tolerated
- HbA1c target with SU/insulin: 53 mmol/mol (higher to reduce hypo risk)
3
Triple therapy / intensification
- Metformin + two other agents from above
- If BMI ≥35 (or lower with ethnic-specific thresholds) and triple oral therapy inadequate: consider GLP-1 RA (semaglutide, liraglutide)
- GLP-1 RAs: significant weight loss, CV benefit, weekly injection (semaglutide)
- Continue GLP-1 RA only if ≥11 mmol/mol HbA1c reduction and ≥3% weight loss at 6 months
4
Insulin
- If oral/injectable therapy insufficient to achieve target
- Usually start with basal insulin (NPH at bedtime, or long-acting analogue e.g. insulin glargine)
- Continue metformin alongside insulin
- Intensify with prandial insulin if needed (basal-bolus regimen)
- DVLA: must inform if on insulin. No Group 2 licence unless hypoglycaemia awareness intact
5
Cardiovascular risk management
- Atorvastatin 20 mg for all T2DM with QRISK >10%
- BP target: <140/90 (or <130/80 if renal disease, eye disease, or cerebrovascular disease)
- ACE inhibitor/ARB if microalbuminuria (ACR >3 mg/mmol) — renoprotective
- Antiplatelet: NOT routine in primary prevention for diabetes (unlike secondary prevention)
Complications
- Microvascular: Diabetic retinopathy (leading cause of blindness in working-age adults), nephropathy (leading cause of ESRD), peripheral neuropathy (glove-and-stocking sensory loss), autonomic neuropathy (gastroparesis, postural hypotension, erectile dysfunction)
- Macrovascular: Coronary artery disease, stroke, peripheral arterial disease — diabetes doubles CVD risk
- Diabetic foot disease: Neuropathy + PVD → ulceration, infection, Charcot arthropathy, amputation
- Hyperosmolar hyperglycaemic state (HHS): Profound hyperglycaemia (>30 mmol/L), hyperosmolality, dehydration WITHOUT significant ketosis — high mortality
- Hypoglycaemia: Drug-induced (sulfonylureas, insulin) — important safety concern
UKMLA Exam Tips
- 1Metformin is ALWAYS first-line. Contraindicated if eGFR <30. Reduce dose if eGFR 30–45
- 2SGLT2i: proven CV and renal benefit — preferred add-on if CVD, HF, or CKD. Watch for: euglycaemic DKA, UTIs, Fournier gangrene
- 3Sulfonylureas (gliclazide): cause WEIGHT GAIN and HYPOGLYCAEMIA — key disadvantage vs other agents
- 4If the question mentions a South Asian patient with BMI 24 and T2DM → lower BMI thresholds apply in high-risk ethnic groups
- 5HbA1c target: 48 if on metformin alone; 53 if on drugs that cause hypoglycaemia (SU, insulin)
- 6Annual screening: eyes, feet, ACR, BP, lipids, HbA1c, renal function — know this routine
- 7HHS (not DKA) is the typical acute emergency in T2DM — glucose >30, hyperosmolar, minimal ketones
practicetest your knowledge on type 2 diabetesApply what you've learnt with UKMLA-style questions from the iatroX Q-Bank — endocrine and beyond.
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