๐ Insulin resistance = when higher insulin levels are required to achieve the same glucose-lowering effect.
This underpins Type 2 Diabetes Mellitus (T2DM) ๐.
๐ About Diabetes
- Chronic hyperglycaemia due to insulin deficiency or resistance โ๏ธ.
- Increases long-term risk of vascular disease โค๏ธ๐ง .
- Not all T2DM patients develop ketosis (unlike T1DM).
๐งฌ Aetiology
- Polygenic inheritance (90% concordance in identical twins).
- Partial loss of beta-cell function in islets of Langerhans + insulin resistance.
- Islet cell amyloid seen at postmortem ๐งช.
โ ๏ธ Diagnostic Criteria
- Fasting plasma glucose โฅ 7.0 mmol/L (x2 if asymptomatic).
- Random plasma glucose โฅ 11.1 mmol/L + symptoms.
- HbA1c โฅ 48 mmol/mol (6.5%) ๐ (unless haemoglobinopathy present).
- OGTT: 2h glucose โฅ 11.1 mmol/L.
๐ฉบ Clinical Features
- Polyuria ๐ฝ, polydipsia ๐ง, unexplained weight loss โ๏ธ.
- Blurred vision ๐๏ธ, recurrent infections (e.g. Candida balanitis ๐).
- Long-term complications: retinopathy ๐, neuropathy ๐ฆถ, nephropathy ๐ฉบ, CVD โค๏ธ.
๐ Blood Glucose Ranges (UK vs US)
| Range | UK (mmol/L) | US (mg/dL) |
|---|
| Normal (Fasting) | 4.0 - 5.9 | 72 - 106 |
| Normal (After Meal) | 4.0 - 7.8 | 72 - 140 |
| Pre-diabetes (Fasting) | 6.0 - 6.9 | 108 - 124 |
| Diabetes (Fasting) | โฅ 7.0 | โฅ 126 |
| Hypoglycaemia | < 4.0 | < 72 |
| Random Diabetes Diagnosis | โฅ 11.1 | โฅ 200 |
๐ Investigations
- Blood glucose, HbA1c, lipid profile.
- U&E, creatinine clearance, urine albumin:creatinine ratio (for nephropathy).
- Annual foot exam + retinal screening.
๐ ๏ธ Management
- ๐ฟ Lifestyle: weight loss, dietary advice, exercise, smoking cessation.
- ๐ฉบ Blood pressure: aim <135/85 mmHg (ACE inhibitor first-line).
- ๐ Glycaemic control: HbA1c target usually 48 mmol/mol; recheck after 2-3 months post-med change.
- Statins + aspirin for vascular protection (if indicated).
๐ Oral Hypoglycaemic Agents
| Drug | Mechanism | Key Points |
|---|
| Metformin | โ Insulin sensitivity | First-line; weight-neutral; avoid if eGFR <30 |
| Sulfonylureas | Stimulate insulin secretion | Risk of hypo; weight gain; useful if not overweight |
| Glitazones | PPAR-ฮณ agonist (โ sensitivity) | Avoid in heart failure; fluid retention |
| SGLT-2 inhibitors | โ Renal glucose excretion | Cause weight loss; good CV benefits; risk of GU infections |
| DPP-4 inhibitors | โ Incretin effect | Weight-neutral, low hypo risk |
๐ต Elderly Management
- Focus on quality of life, not strict glycaemic control.
- Relaxed HbA1c targets (58โ64 mmol/mol).
- Avoid hypos โ choose agents carefully.
๐ก Clinical Pearl:
Always treat the patient, not just the numbers. A frail 85-year-old with HbA1c 60 mmol/mol may not benefit from aggressive therapy, but a 40-year-old with complications needs tighter control.
๐ Case Example
๐ฉ A 52-year-old woman with BMI 33 presents with polyuria ๐ฝ, polydipsia ๐ง and tiredness.
Fasting glucose: 8.4 mmol/L, HbA1c: 63 mmol/mol.
โ
Diagnosis: Type 2 Diabetes.
๐ ๏ธ Management: Start with lifestyle modification + metformin, monitor HbA1c, and add further therapy if control not achieved.
References
