Diabetes Mellitus

Meet the patient

A 24-year-old primary-school teacher arrives in AandE after three weeks of passing urine every forty minutes through the night, drinking four litres of juice a day, and dropping a stone she did not have to lose. Her breath smells of pear-drops, she is breathing deep and fast at 28 a minute, and her capillary glucose is unrecordable-high.[1][6]

The three questions this vignette forces on you are the three this whole page exists to answer: what is this? (a hyperglycaemic emergency, almost certainly new T1DM), what do I do in the next hour? (fluids, then fixed-rate insulin, then potassium), and why did nobody spot it sooner? (the osmotic prodrome was blamed on a urine infection).[1]

Viva gold — why the words: diabetes from the Greek diabainein — "to pass through", a siphon; mellitus from the Latin for "honey-sweet", after Thomas Willis in 1674 famously tasted diabetic urine and noted it sweet, distinguishing it from diabetes insipidus — "tasteless". Two and a half centuries before the lab, the tongue made the diagnosis.[1]

What diabetes is — and the one number that defines it

Diabetes mellitus is sustained hyperglycaemia from a mismatch between insulin supply and demand. The ADA 2019 Standards of Care and the 2019 ESC/EASD Guidelines frame every subtype that way: the final common pathway is glucose the body cannot clear, and the aetiology decides the treatment.[1][3]

It is not one disease. It is four aetiological buckets — type 1, type 2, gestational, and "other specific types" (MODY, LADA, drug- or pancreas-induced, endocrinopathic) — plus a warning state called prediabetes. Same hyperglycaemia, very different management.[1][4]

It is not a glucose meter reading alone. Stress, steroids, a dextrose drip, and a single piece of cake all raise glucose; the diagnosis needs a sustained threshold or a confirmatory second test, with one exception — a patient in hyperglycaemic crisis is diabetic the moment you see them.[1]

The diagnostic quartet — four ways to call it

Four routes, one diagnosis. Memorise them as a cluster, not a list, because the examiner will ask you to reproduce each threshold with its unit.[1]

1. HbA1c over 6.5 percent (48 mmol/mol) — reflects 8 to 12 weeks of ambient glycaemia; needs an NGSP-aligned, standardised assay.[18]
2. Fasting plasma glucose over 7.0 mmol/L (126 mg/dL) — fasting means no calories for at least 8 hours.[18]
3. 2-hour plasma glucose over 11.1 mmol/L (200 mg/dL) during a 75 g oral glucose tolerance test (OGTT).[18]
4. Random plasma glucose over 11.1 mmol/L (200 mg/dL) with classic symptoms — polyuria, polydipsia, weight loss — or hyperglycaemic crisis.[26]

The threshold number rule: 6.5-7.0-11.1. A1c six-point-five, fasting seven-point-oh, OGTT and random eleven-point-one. Say it as one breath and you have the diagnostic quartet for life.[18][26]

Confirmation rule: in an asymptomatic patient, repeat a different category — HbA1c over 6.5 plus fasting over 7.0, for example — before committing to the diagnosis. A single symptomatic random over 11.1 needs no second test.[18]

Prediabetes — the band that earns an intervention. Impaired fasting glucose, impaired glucose tolerance, or an HbA1c below the diabetic threshold but above the normal range. The Diabetes Prevention Program proved the point: a lifestyle programme cut progression to diabetes by 58 percent, and metformin 850 mg twice daily by 31 percent.[15][18]

[1]

Meet the family — six faces of diabetes

Type the patient before you treat them — the label decides the first prescription. The ADA and ESC share the same four-bucket framework, expanded here into the six phenotypes a final-prof candidate must separate at the bedside.[1][3]

[1]

How common, how deadly

Diabetes is the fastest-growing non-communicable burden on the planet, and T2DM is the landlord. The IDF Atlas 10th edition puts roughly 537 million adults (about 1 in 11) on the list, projected to hit 643 million by 2030 and 783 million by 2045 — and half of them do not yet know.[3][4]

[18] [15] [7] [9] [6] [8]

T1DM is 5 to 10 percent of the total, peaks at ages 5 to 7 and again at puberty, and is rising about 3 percent per year globally — driven by environmental triggers (enteroviruses, diet, vitamin D, the hygiene hypothesis) on HLA-DR3/DR4 susceptibility. Finland wears the crown at roughly 60 cases per 100,000 children per year.[5][6]

T2DM owns 90 to 95 percent, tracks obesity, ageing and urbanisation, and bites South Asian, Afro-Caribbean, Middle Eastern and Pacific Island populations hardest and earliest — high genetic susceptibility meeting a rapidly westernised lifestyle.[3][4]

The risk-factor shortlist for T2DM runs on autopilot: overweight and obesity (every 1 kg/m-squared above 25 adds roughly 12 percent risk), ethnicity, age over 45, a first-degree relative (2- to 6-fold), prior gestational diabetes (30 to 50 percent progress within a decade), prediabetes, established cardiovascular disease, PCOS, fatty liver, sleep apnoea, and the usual suspects — steroids, antipsychotics, thiazides, tacrolimus.[1]

Why it kills: diabetes is a leading cause of blindness, end-stage renal disease, non-traumatic lower-limb amputation and premature cardiovascular death — the reason glycaemia is only half the job; blood pressure, lipids, weight and smoking complete it.[3][4]

Why the beta cell fails

Whatever the subtype, the final failure is the same: the beta cell can no longer match insulin output to glucose load. In T1DM the cell is destroyed; in T2DM it is exhausted on a background of resistance; in MODY it is miswired by a single gene.[1]

Type 1 — autoimmune beta-cell destruction. CD4+ and CD8+ T cells infiltrate the islets (insulitis) and dismantle beta cells over months to years on HLA-DR3-DQ2 / DR4-DQ8 susceptibility, triggered by viruses or other environmental hits. Autoantibodies (anti-GAD65, anti-IA2, anti-ZnT8, anti-insulin) are markers, not the executioners. As mass falls, insulin and C-peptide become unmeasurable, glucagon runs unchecked, and ketogenesis accelerates — which is why DKA is a T1DM disease.[5][6]

Type 2 — two interlocking defects, and you must name both.[1]

1. Insulin resistance in muscle, liver and adipose tissue — the liver fails to suppress glucose output, muscle fails to take glucose up, and adipose dumps free fatty acids that worsen both. Obesity, ectopic fat, sedentary life, inflammation and ageing drive it.[1][3]
2. Progressive beta-cell dysfunction — mass falls, secretion drops, the cell de-differentiates; glucotoxicity, lipotoxicity, islet amyloid (IAPP) and inflammation do the damage. By diagnosis, beta-cell function is already down 50 to 60 percent and falls 5 to 10 percent a year.[3]

[1]

The consultant's principle — say it in the viva: glucotoxicity and lipotoxicity are reversible, beta-cell destruction is not. That single sentence explains why T1DM needs insulin urgently and forever, while early T2DM can be slowed, stalled, even sent into remission with weight loss, GLP-1 receptor agonists, SGLT2 inhibitors and bariatric surgery.[3]

Gestational diabetes is a stress test: the physiological insulin resistance of pregnancy (human placental lactogen, progesterone, cortisol, TNF-alpha) outruns the woman's secretory reserve in roughly 5 to 15 percent of pregnancies, peaking late in the second trimester.[1][3]

How they walk in — three doors

Diabetes knocks on three doors: a hyperglycaemic emergency, the classic osmotic prodrome, or an incidental screening result. Which door decides whether you resuscitate, investigate, or simply confirm.[1]

The osmotic symptom cluster — any hyperglycaemic state, any type:[1]

• Polyuria — osmotic diuresis once glucose breaches the renal threshold; litres a day can be lost, and secondary nocturnal enuresis in a previously dry child is a classic clue.
• Polydipsia — the osmotic pull on the thirst centre; the patient drinks litres, often cold or sweet.
• Weight loss — the T1DM signature: with no insulin, glucose cannot be stored, and the body burns protein and fat instead; 5 to 10 percent of body weight in weeks.
• Fatigue and blurred vision — cellular starvation, disturbed sleep, and osmotic lens swelling (do not prescribe new glasses until glycaemia settles).
• Pruritus vulvae, balanitis, recurrent candidiasis, recurrent UTI, recurrent skin infection, a leg ulcer that will not heal — glucose feeds Candida and bacteria; diabetes is on the differential of any adult with thrush or cellulitis.[1]

Type 1 — the acute picture: days to weeks of polyuria, polydipsia and weight loss, often ending in DKA (vomiting, abdominal pain, Kussmaul breathing, dehydration, drowsiness). In a child, add abdominal pain, falling school performance and secondary enuresis to the triad.[5][6]

Type 2 — the chronic picture: months to years of insidious symptoms, or no symptoms at all — the diagnosis lands on a screening HbA1c, or after a complication (retinopathy at the optician, an MI, a foot ulcer). Roughly 20 to 30 percent already have tissue damage at diagnosis.[1][3]

Hyperglycaemic emergencies — flag and escalate:[1]

• DKA — hyperglycaemia, ketosis and high-anion-gap metabolic acidosis; polyuria, vomiting, Kussmaul respiration, dehydration, abdominal pain, altered sensorium. Classically T1DM but also LADA, pregnancy, stress, and euglycaemic DKA on SGLT2 inhibitors — the absence of marked hyperglycaemia delays recognition of SGLT-2 inhibitor-associated ketoacidosis.[21]
• HHS — severe hyperglycaemia with serum osmolality greater than 320 mOsm/kg, minimal to no ketones and profound dehydration, typically in an older T2DM triggered by infection, stroke or acute coronary syndrome; mortality is about ten-fold higher than DKA.[23][25]

The presentations examiners love to spring: the older "prostate trouble" patient whose nocturia is actually polyuria; the teenager "doing drugs" who is in DKA; the asymptomatic pregnant woman screened at 28 weeks; the thin 30-something labelled T2DM who is LADA; and the Cushingoid or acromegalic patient whose diabetes is secondary.[1]

What else drives the glucose up — the differential

Two questions, always: what is causing the hyperglycaemia, and what complication must I exclude? The first protects the diagnosis; the second protects the patient.[1]

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The bedside rule for the examiner: check a capillary glucose and a basic blood panel in any adult with polyuria, polydipsia, recurrent infections, unexplained weight loss, a non-healing foot ulcer, or hyperglycaemic crisis — then let HbA1c, autoantibodies, C-peptide and the clinical phenotype separate stress hyperglycaemia, prediabetes, diabetes and its subtypes.[1][3]

The bedside and the annual review

Bedside assessment has two jobs — diagnose, then characterise. In the unwell diabetic, glucose is a fifth vital sign and the resuscitation priorities come first.[1]

Acute bedside — the unwell hyperglycaemic patient:[1]

• ABCDE plus capillary glucose as a vital sign.
• Hydration — JVP, mucous membranes, skin turgor, lying and standing blood pressure; a 20/10 mmHg postural drop suggests 1 to 2 L deficit in an adult.
• Respiratory pattern — Kussmaul breathing (deep, sighing, rate over 25) and pear-drop breath in ketosis.
• Abdomen — DKA mimics an acute abdomen; also feel for pancreatitis and hepatomegaly (NAFLD).
• Neurology — GCS, focal deficits (HHS can stroke-mimic and reverse with rehydration), glove-and-stocking neuropathy, foot ulcer.
• Cardiovascular — rate, postural change, ankle-brachial pressure index, carotid and femoral bruits.[3][4]

The annual "review and recall" — what every diabetic gets each year:[1]

• History — symptoms, hypoglycaemia frequency, sick-day rule knowledge, foot care, diet, exercise, smoking, alcohol, driving, pregnancy plans.
• Examination — weight, BMI, waist (over 94 cm men or 80 cm women; over 90 cm in South Asian men), blood pressure (target under 130/80), foot inspection, injection sites for lipohypertrophy, dental review.
• Tests — HbA1c, fasting lipids, urinary albumin-to-creatinine ratio, eGFR, LFTs, TSH.
• Referrals — annual retinal photography, podiatry, diabetes specialist nurse, dietitian, and structured education (DAFNE for T1DM, DESMOND or X-PERT for T2DM).[1][3]

The foot — neuropathy, ischaemia, infection. Examine with a monofilament for protective sensation, a tuning fork for vibration, pinprick, ankle reflexes, and the dorsalis pedis and posterior tibial pulses, and measure the ankle-brachial pressure index (low values suggest peripheral arterial disease; very high values suggest calcified, non-compressible vessels). Risk-stratify: low risk (none), moderate (neuropathy or ischaemia or deformity), high (active ulcer, Charcot, prior ulcer or amputation).[1]

The retina — fundoscopy is too unreliable to grade. Diabetic retinopathy screening uses mydriatic digital retinal photography graded by a trained screener. Refer to ophthalmology for pre-proliferative or proliferative change, maculopathy, hard exudates near the macula, vitreous haemorrhage, or any unexplained vision loss.[1]

Investigations — diagnose, type, and stage

Three columns of tests: confirm the diagnosis, type the diabetes, and stage the complications. A final-prof candidate names a test from each.[1]

Confirm the diagnosis:[1]

• HbA1c — over 6.5 percent (48 mmol/mol) diagnostic in non-pregnant adults.[18] Assay interference — iron deficiency, CKD, haemolysis, haemoglobinopathy, pregnancy — can bias the result in either direction; fall back on glucose criteria when the assay is unreliable.[1]
• Fasting plasma glucose — over 7.0 mmol/L (126 mg/dL); fasting means no calories for at least 8 hours.[18]
• 75 g OGTT — 2-hour glucose over 11.1 mmol/L (200 mg/dL); in pregnancy use IADPSG thresholds (fasting over 5.1, 1-hour over 10.0, 2-hour over 8.5 mmol/L) at 24 to 28 weeks.[18][24]
• Random plasma glucose — over 11.1 mmol/L (200 mg/dL) with classic symptoms is diagnostic.[26]
• Confirmation — two abnormal results from different categories unless unequivocal hyperglycaemic crisis.[1]

Type the diabetes:[1]

• T1DM-specific autoantibodies — anti-GAD65, anti-IA2, anti-ZnT8, anti-insulin — send when onset is acute or the type is unclear.
• C-peptide — low or undetectable (under 0.2 nmol/L) in established T1DM; preserved or high in early T2DM. High C-peptide with hypoglycaemia means insulinoma or sulfonylurea; high insulin with suppressed C-peptide means exogenous (factitious) insulin.
• Genetic testing for MODY when the pedigree fits (autosomal dominant, onset before 25, non-obese, antibody-negative).[1]

Stage the complications and monitor:[1]

• HbA1c regularly — more often when treatment is changing, at least annually when stable.
• Fasting lipids annually; triglycerides flag non-adherence and pancreatic risk.
• Urinary albumin-to-creatinine ratio on a first-morning spot urine — a raised ratio marks early nephropathy; CKD staging drives drug choice.
• Creatinine and eGFR at baseline and at least annually — CKD stage drives metformin, SGLT2i and ACE-inhibitor decisions.
• LFTs (NAFLD), TSH (autoimmune thyroid, especially T1DM), and vitamin B12 periodically on long-term metformin — biochemical deficiency can develop.[1][2]
• ECG and consider echo if cardiovascular risk is high.[1][2]

In the acutely unwell patient, add the emergency panel: venous gas (pH, bicarbonate, lactate), capillary beta-hydroxybutyrate, electrolytes and anion gap, osmolality if HHS is suspected, and an infection screen (FBC, CRP, blood culture, urine, chest X-ray). For unexplained hypoglycaemia, add a sulfonylurea screen, insulin and C-peptide, and cortisol — to catch the overdose, the factitious injection, and the Addison crisis.[1]

In pregnancy: tight pre-conception control for pre-existing diabetes, a 75 g OGTT at 24 to 28 weeks with IADPSG thresholds, frequent self-monitored glucose if on insulin, and third-trimester growth surveillance.[24]

The killing emergencies — DKA, HHS, hypoglycaemia

These three kill diabetics, and each has a bundle you reproduce verbatim. Detail lives in the dedicated topics; the ward-round summary follows. Humour is off for the rest of this section.[1]

Diabetic ketoacidosis — the bundle

DKA is hyperglycaemia, ketosis and high-anion-gap metabolic acidosis (pH below 7.3, bicarbonate below 15 mEq/L, glucose over 600 mg/dL). The bundle, in order:[19]

• Fluids first — restore the deficit with isotonic saline, reassessing frequently; move to glucose-containing fluid once the glucose falls, and keep the rate measured in children.
• Potassium before and during insulin — check potassium with the gases, replace deficit, and recheck serially; insulin drives potassium into cells and uncorrected hypokalaemia kills.
• Fixed-rate intravenous insulin infusion 0.1 units/kg/hour — the standard adult and paediatric dose; a low-dose 0.05 units/kg/hour infusion was non-inferior in young children with fewer therapy-related complications.[20]
• Find and treat the precipitant — infection (commonest), missed insulin, myocardial infarction, stroke, surgery, drugs (SGLT2i, steroids).[21]
• Watch for cerebral oedema — the feared paediatric complication; gradual rehydration and no insulin bolus.[20]

Hyperglycaemic hyperosmolar state — the bundle

HHS is marked hyperglycaemia with effective serum osmolality greater than 320 mOsm/kg, little or no metabolic acidosis, and minimal to no ketones, in a profoundly dehydrated older patient. Triggers are usually infection, stroke or acute coronary syndrome, and mortality is far higher than in DKA.[23][25]

• Aggressive volume repletion of the osmotic losses — the priority, with close haemodynamic and sodium monitoring.
• Insulin therapy — alongside fluids, once volume replacement is under way, watching for the sharp falls in glucose and osmolality that threaten the brain.
• Treat the underlying cause — the trigger usually decides the outcome.[23]

Hypoglycaemia — the bundle

Hypoglycaemia is a low blood glucose with symptoms — treat first, investigate after.[22]

• Mild (conscious, able to swallow) — 15 to 20 g of oral glucose or sucrose, repeated after 10 to 15 minutes; then complex carbohydrate to prevent recurrence.[22]
• Moderate (confused but can swallow with help) — oral glucose gel plus food; teach carers and partners.
• Severe (unconscious, fitting, or unsafe swallow) — 10 percent intravenous dextrose or 1 mg intramuscular glucagon in the unresponsive adult.[22]
• Investigate — sulfonylurea exposure, factitious insulin (insulin and C-peptide screen), and adrenal insufficiency; find the precipitant before discharge.[1]

The exam upshot for any acute diabetic presentation: capillary glucose is a fifth vital sign; DKA needs fluids then fixed-rate insulin then potassium; HHS needs fluids and prophylactic LMWH; hypoglycaemia needs glucose or glucagon — and the precipitant must always be found.[1][3]

Definitive therapy — the cause-specific ladder

Treatment follows the aetiology, but four elements are universal: education, lifestyle, glycaemic and cardiovascular risk control, and complication surveillance. Get all four right or you are practising 1990s diabetes care.[1]

Universal elements — every patient, every visit:[1]

• Structured education — DAFNE (Dose Adjustment for Normal Eating) for T1DM, DESMOND or X-PERT for T2DM, medical nutrition therapy with a dietitian, carbohydrate counting for T1DM.
• Lifestyle — the DPP programme targeted at least 150 minutes of physical activity per week and at least 7 percent weight loss, and cut progression to diabetes by 58 percent; stop smoking; Mediterranean-style low-glycaemic-load diet.[15]
• Weight — even modest weight loss changes trajectory; bariatric surgery for selected patients with T2DM and obesity, especially if poorly controlled.
• Cardiovascular risk — treat blood pressure and lipids to guideline targets; ACE-inhibitor therapy with ramipril 10 mg daily cut the composite of myocardial infarction, stroke or cardiovascular death by 25 percent in people with diabetes (MICRO-HOPE).[17]
• HbA1c target — intensive control aiming near 7 percent: the UKPDS intensive policy held median HbA1c at 7.0 versus 7.9 percent on conventional care, at the price of hypoglycaemia risk — individualise.[16]

[6] [5] [8]

[3] [7]

Drug doses you carry onto the ward

Name the drug, the dose, the mechanism, and the pitfall — that is the viva format. Reproduce the doses verbatim.[1]

• Metformin — start low with meals and titrate; 850 mg twice daily was the DPP dose. Reduces hepatic gluconeogenesis via AMPK, improves peripheral sensitivity, modest weight loss, low hypoglycaemia risk. Side-effects: gastrointestinal upset and B12 deficiency. Contraindicated in severe renal impairment; withhold for contrast and in sepsis — lactic acidosis is rare but feared. The evidence: UKPDS 34 metformin cut diabetes-related endpoints by 32 percent, diabetes-related death by 42 percent and all-cause mortality by 36 percent in overweight T2DM.[15][8]
• Sulfonylurea (glimepiride, gliclazide) once daily — start low, titrate. Blocks the beta-cell K-ATP channel and releases insulin. Real risks: hypoglycaemia and weight gain; avoid in the elderly and in renal impairment. UKPDS 33 used chlorpropamide, glibenclamide or glipizide as intensive therapy.[16]
• DPP-4 inhibitor (sitagliptin, linagliptin) once daily. Prolongs endogenous GLP-1; weight neutral, low hypoglycaemia risk.[1]
• GLP-1 receptor agonist — once-weekly semaglutide 0.5 mg or 1.0 mg (SUSTAIN-6); liraglutide and dulaglutide also proven. Glucose-dependent insulin release, glucagon suppression, slowed gastric emptying, central satiety. Cardiovascular benefit: liraglutide cut MACE by 13 percent (HR 0.87, LEADER), dulaglutide by 12 percent (HR 0.88, REWIND), semaglutide by 26 percent (HR 0.74, SUSTAIN-6) in type 2 diabetes at high cardiovascular risk; gastrointestinal adverse events are the commonest drawback. Oral semaglutide is available.[10][9][11]
• Empagliflozin 10 mg or 25 mg orally once daily. SGLT2 inhibitor — blocks renal proximal tubular glucose reabsorption. EMPA-REG OUTCOME showed a 38 percent drop in cardiovascular mortality, 32 percent all-cause mortality and 35 percent HF hospitalisation in T2DM with established CVD; dapagliflozin 10 mg daily cut the composite of worsening HF or cardiovascular death by 26 percent in HFrEF regardless of diabetes (DAPA-HF, HR 0.74) and slowed renal decline in CKD (DAPA-CKD, HR 0.61); canagliflozin cut the renal composite by 30 percent (CREDENCE, HR 0.70). Pitfalls: euglycaemic DKA, genital infection, osmotic diuresis and dehydration.[7][12][13][14][21]
• Pioglitazone once daily. Thiazolidinedione — PPAR-gamma agonist, reduces insulin resistance. Side-effects: weight gain, fluid retention, heart failure, fracture risk; useful in fatty liver.[1]
• Basal insulin (glargine, detemir, degludec) once daily — long-acting "peakless" basal; titrate to the fasting glucose target.[1]
• Rapid-acting prandial insulin (lispro, aspart, glulisine) with meals — titrate to post-prandial and pre-meal targets.[1]
• NPH insulin — intermediate-acting, cheaper than analogues, given twice daily; useful in T2DM and gestational diabetes.[1]
• ACE-inhibitor — ramipril 10 mg daily cut MI, stroke or cardiovascular death by 25 percent in people with diabetes (MICRO-HOPE); add guideline-indicated statin therapy and secondary-prevention aspirin per cardiovascular risk.[17]

[15] [7] [10] [12] [13] [20] [17]

Insulin regimens — name the four

If a viva asks "describe an insulin regimen," you give one of these four by name. Match the regimen to the patient's lifestyle and cognition.[1]

• Basal-bolus (multiple daily injections) — long-acting basal (glargine or degludec once daily) plus rapid-acting bolus (lispro or aspart) with each meal. Standard for T1DM and advanced T2DM; the most physiological and the most flexible.
• Premixed (biphasic) — short- and intermediate-acting insulin in a fixed ratio (30/70 or 50/50), given twice daily before breakfast and dinner. Convenient but inflexible — the dose cannot be split for activity or meal size.
• Continuous subcutaneous insulin infusion (CSII, the pump) — programmable continuous basal plus mealtime boluses. For selected T1DM, especially brittle, pregnant, or those chasing tight control; hybrid closed-loop systems now automate the basal.
• Twice-daily NPH — the cost-effective basal option in T2DM and gestational diabetes; intermediate-acting, given morning and evening.[1]

Sick-day rules — never stop the basal

Intercurrent illness raises glucose and ketones; the patient who stops insulin because they "aren't eating" is the one who ends up in DKA. Teach this to every insulin-treated patient, their family, and the school nurse.[1]

[1]

• Never stop insulin, even if not eating — withhold mealtime bolus if fasting, but the basal must continue.
• Check capillary glucose and ketones every 2 to 4 hours.
• Use an illness correction scale — extra rapid-acting analogue per sick-day rules if ketones rise; never chase a correction without checking ketones.
• Seek medical advice early — DKA can evolve in hours.[1]

The 2019 ESC/EASD stepwise algorithm — comorbidity, not potency

Modern T2DM care chooses the second agent by what else is wrong with the patient, not by how many points it drops the HbA1c. That single shift is the most examinable idea in contemporary diabetes.[3][4]

Step 1 — lifestyle plus metformin, for everyone. Metformin stays the backbone: cheap, weight neutral, no hypoglycaemia, possible cardiovascular benefit, and UKPDS 34 behind it.[8]

Step 2 — add by comorbidity:[3][4]

• Established atherosclerotic cardiovascular disease — GLP-1 receptor agonist (liraglutide, semaglutide, dulaglutide) or SGLT2 inhibitor (empagliflozin, canagliflozin) first. EMPA-REG OUTCOME cut cardiovascular death by 38 percent, all-cause death by 32 percent and HF hospitalisation by 35 percent; LEADER (liraglutide, HR 0.87), REWIND (dulaglutide, HR 0.88) and SUSTAIN-6 (semaglutide, HR 0.74) all reduced MACE.[7][9][11][10]
• Heart failure — SGLT2 inhibitor first (empagliflozin, dapagliflozin); in HFrEF, dapagliflozin 10 mg daily cut worsening HF or cardiovascular death by 26 percent regardless of diabetes status (DAPA-HF).[12]
• Chronic kidney disease — SGLT2 inhibitor: dapagliflozin cut the composite of sustained eGFR decline, end-stage kidney disease or renal death by 44 percent (DAPA-CKD, HR 0.56 for the renal composite) and canagliflozin cut the renal composite by 30 percent (CREDENCE).[13][14]
• Obesity — GLP-1 RA first, or dual GLP-1/GIP tirzepatide; combine with intensive lifestyle (the DPP lifestyle arm beat metformin) and consider bariatric surgery.[15]
• No comorbidity, no obesity — DPP-4 inhibitor or sulfonylurea, by cost and tolerability.[1]

Step 3 — triple therapy or basal insulin. Triple oral (metformin plus sulfonylurea plus DPP-4i or SGLT2i or pioglitazone), or add a GLP-1 RA, or start titrated basal insulin if HbA1c is still above target.[1]

Step 4 — basal-bolus or premixed insulin plus bariatric surgery assessment for selected patients with obesity and T2DM.[1]

Step 5 — diabetes technology. Continuous glucose monitoring, flash monitoring, insulin pumps and hybrid closed-loop systems for selected T1DM; automated insulin delivery on the horizon.[3][4]

Subtypes and scenarios — the answers that separate candidates

Examiners probe the subtype-specific answer, not the generic one. Each of these is a stem waiting to happen.[1]

Type 1 — across the age range. Absolute insulin deficiency plus the DCCT/EDIC legacy: intensive therapy cut retinopathy onset by 76 percent, and over a mean 17 years of EDIC follow-up cut any cardiovascular disease event by 42 percent and nonfatal MI, stroke or cardiovascular death by 57 percent — "metabolic memory" in action. CGM and hybrid closed-loop pumps are now standard; sick-day rules go home with every patient.[6][5]

Type 2 — adult and increasingly adolescent. UKPDS 33 and 34 proved tight glycaemia with metformin reduces long-term complications in overweight T2DM, and the 2019 ESC/EASD algorithm chooses add-on therapy by comorbidity. Weight loss is now central to management, with intensive lifestyle programmes and bariatric surgery in selected patients.[16][8][3]

Gestational diabetes. Screen with a 75 g OGTT at 24 to 28 weeks using IADPSG criteria (fasting over 5.1, 1-hour over 10.0, 2-hour over 8.5 mmol/L). Diet and exercise first; metformin or insulin if targets are missed. Re-screen postpartum — the future T2DM risk is high — and plan pre-conception counselling for established diabetes before the next pregnancy.[24]

MODY / monogenic. GCK-MODY needs no treatment; HNF1A-MODY (MODY 3) responds exquisitely to low-dose sulfonylurea; HNF1B-MODY (MODY 5) causes RCAD — renal cysts and diabetes. Neonatal diabetes from KCNJ11 or ABCC8 mutations responds to high-dose sulfonylurea, not insulin.[1]

LADA. Adult-onset, autoimmune, anti-GAD positive, C-peptide falling; insulin is usually needed within 6 months to 6 years and may preserve residual beta-cell function if started early.[1]

Secondary diabetes. Identify and treat the cause: taper steroids and add metformin or insulin for steroid-induced disease; resect the Cushing, acromegaly or phaeochromocytoma; give pancreatic enzyme replacement in chronic pancreatitis and titrate insulin carefully through the malabsorption.[1][3]

Perioperative. Type 1: never stop basal insulin; convert to a variable-rate intravenous insulin infusion with 5 percent or 10 percent dextrose for major surgery, list first thing, check glucose every 1 to 2 hours. Type 2 on metformin: omit on the day of surgery (lactic acidosis if renal function dips), resume when eating; continue sulfonylurea only if eating; convert to VRIII if prolonged fasting or major surgery.[1][3]

Elderly and frail. Loosen the HbA1c target; avoid sulfonylureas and aggressive insulin titration; watch dehydration and falls on SGLT2i and gastrointestinal effects on GLP-1 RA. Emphasise sick-day rules and driving regulations.[3]

Children and adolescents. T1DM dominates but T2DM is rising with obesity; school carb-counting and pumps are standard. Transition to adult care around 18 with a coordinated handover covering driving, alcohol, sick-day rules, contraception and pregnancy, and DKA prevention during intercurrent illness.[1][5]

Complications — micro, macro, and the foot

Chronic hyperglycaemia damages the small vessels, the large vessels, and the nerves; acute hyperglycaemia and its treatment cause the metabolic emergencies. Tight glycaemia blunts the microvascular damage — the DCCT and UKPDS lessons that reshaped the field.[1]

Microvascular — retinopathy, nephropathy, neuropathy — driven by glucose, blunted by control (DCCT for T1DM, UKPDS for T2DM).[5][6][8]

[6] [13] [14]

Macrovascular — diabetes roughly doubles to quadruples cardiovascular risk and CVD is the leading cause of death in T2DM.[3][4]

• Coronary disease — often silent thanks to autonomic neuropathy; troponin and ECG on admission, not history. Guideline statin and antiplatelet therapy in secondary prevention; ramipril 10 mg daily cut MI, stroke or cardiovascular death by 25 percent in diabetes (MICRO-HOPE).[17]
• Cerebrovascular — stroke risk roughly doubled; atrial fibrillation more common; anticoagulate by CHA2DS2-VASc.
• Peripheral arterial disease — claudication, absent pulses, ABPI under 0.9; intensive risk-factor control, cilostazol, supervised exercise, revascularisation for critical limb ischaemia.
• Heart failure — diabetes raises incident HF, and SGLT2 inhibitors now treat HFrEF regardless of diabetes status: dapagliflozin 10 mg daily cut worsening HF or cardiovascular death by 26 percent (DAPA-HF).[12]

The foot and Charcot neuroarthropathy.[1]

• Diabetic foot ulcer — neuropathy plus trauma plus deformity plus ischaemia plus infection, graded by Wagner and SINBAD. Multidisciplinary care: wound care, offloading in a total contact cast, IV antibiotics for infection, revascularisation for PAD, surgical debridement; avoid amputation where possible.
• Charcot foot — acute, hot, swollen, deformed (often rocker-bottom midfoot) in a neuropathic patient; offload in a total contact cast, surgery in selected chronic cases, bisphosphonates controversial.[1]

Other complications worth a line: autonomic neuropathy (gastroparesis — small frequent meals, metoclopramide or domperidone; erectile dysfunction — PDE-5 inhibitor; bladder — intermittent self-catheterisation; orthostatic hypotension — midodrine); skin (necrobiosis lipoidica, shin spots, bullosis diabeticorum, lipohypertrophy); periodontal disease (bidirectional with glycaemia); bone (fracture risk, FRAX adjustment); cognition (vascular dementia); cancer (modestly raised pancreatic, hepatic, colorectal, breast, bladder); and limited joint mobility — the "prayer sign" of cheiroarthropathy.[1]

Prognosis and disposition

Prognosis tracks duration, glycaemic burden, blood pressure, lipids, smoking and established complications — especially CKD, CVD, HF, retinopathy and neuropathy. Cardiovascular disease remains the leading cause of death, and the modern agents (SGLT2 inhibitors, GLP-1 receptor agonists) improve cardiorenal outcomes independent of glucose — the central teaching shift from the old "glucose-only" paradigm.[3]

Diagnostic thresholds — reproduce exactly: diabetes if fasting glucose 7.0 mmol/L (126 mg/dL) or more, 2-hour 75 g OGTT 11.1 mmol/L (200 mg/dL) or more, HbA1c 6.5 percent (48 mmol/mol) or more, or a random glucose 11.1 mmol/L (200 mg/dL) or more with classic symptoms. Confirm asymptomatic diagnoses with a repeat test.[18][26]

Glycaemic targets — individualise: the UKPDS intensive policy held HbA1c at 7.0 versus 7.9 percent and reduced microvascular complications at the cost of more hypoglycaemia — aim near 7 percent where it is safe, and loosen the target with frailty, limited life expectancy or hypoglycaemia history.[16]

Disposition triggers: new T1DM, ketosis-prone or clearly insulin-deficient — urgent specialist start of insulin education; pregnancy — combined diabetes antenatal clinic; eGFR decline or albuminuria — ACE-I/ARB, SGLT2i, nephrology if rapid progression; foot ulcer or infection — multidisciplinary foot service within the week if severe; painful neuropathy, proliferative retinopathy, acute coronary syndrome or heart failure — disease-specific pathways.[1]

Special populations — thresholds and choices that move

Type 1 diabetes. Absolute insulin deficiency, lifelong insulin (MDI or pump), sick-day rules, ketone testing, DKA prevention education. Screen associated autoimmunity (thyroid, coeliac). Carbohydrate counting and hypoglycaemia recognition are survival skills.[5][6]

Pregnancy — pre-existing and gestational. Tighter targets; insulin is the gold standard for pre-existing diabetes (oral agents are region-specific). Screen GDM with a 75 g OGTT per IADPSG criteria — India often uses the DIPSI single-step non-fasting approach; know both. Postpartum OGTT for every GDM mother; the future T2DM risk is high.[24]

Elderly and frail. Prioritise hypoglycaemia avoidance over aggressive HbA1c. Prefer low-hypoglycaemia agents (DPP-4i; carefully selected SGLT2i or GLP-1 RA where the benefit is clear); simplify insulin (basal plus correction rather than complex basal-bolus if cognition is limited).[3]

Chronic kidney disease. Dose-adjust and typically stop metformin in advanced CKD; prefer an SGLT2i for kidney and HF benefit — dapagliflozin cut the primary composite by 39 percent (HR 0.61) in CKD regardless of diabetes; GLP-1 RA for cardiovascular benefit and when SGLT2i is unsuitable; ACE-I or ARB for albuminuria.[13][9]

Heart failure and ASCVD. Prefer SGLT2 inhibitors (HF and CKD benefit, DAPA-HF) and GLP-1 receptor agonists with proven MACE reduction in ASCVD (LEADER, SUSTAIN-6, REWIND); avoid thiazolidinediones in HF.[12][9][10][11]

Infection and surgery. Stress hyperglycaemia worsens outcomes; hold SGLT2i perioperatively and during acute illness (euglycaemic DKA risk); provide basal insulin for insulin-deficient patients even when fasting, with glucose monitoring; restart oral agents when eating and stable.[1]

Steroid-induced hyperglycaemia. Often post-prandial predominant; monitor and use temporary sulfonylurea or insulin protocols; plan the taper as the steroid tapers.[1]

The trials that changed practice

Name the trial, the population, the result, and what it changed — that is the evidence viva.[5][6][7][8]

• DCCT (NEJM 1993) — intensive insulin therapy in T1DM cut retinopathy onset by 76 percent and progression by 54 percent over 6.5 years. Established that tight control matters in T1DM.[6]
• DCCT/EDIC follow-up (Nathan, NEJM 2005) — early intensive control conferred cardiovascular protection years later ("metabolic memory"): any cardiovascular disease event down 42 percent, nonfatal MI, stroke or cardiovascular death down 57 percent over a mean 17 years.[5]
• UKPDS 33 and 34 (Lancet 1998) — intensive glycaemia (HbA1c 7.0 vs 7.9 percent) with sulfonylurea or insulin cut microvascular complications (33); metformin in overweight T2DM cut diabetes-related endpoints 32 percent, diabetes-related death 42 percent and all-cause mortality 36 percent (34).[16][8]
• DPP (NEJM 2002) — in prediabetes, lifestyle cut progression to diabetes 58 percent and metformin 850 mg twice daily 31 percent.[15]
• MICRO-HOPE (Lancet 2000) — ramipril 10 mg daily cut MI, stroke or cardiovascular death 25 percent in people with diabetes.[17]
• EMPA-REG OUTCOME (Zinman, NEJM 2015) — empagliflozin 10 or 25 mg daily cut cardiovascular mortality 38 percent, all-cause mortality 32 percent and HF hospitalisation 35 percent in T2DM with CVD. Rewrote the T2DM algorithm around cardiorenal benefit.[7]
• Modern CVOTs — LEADER (liraglutide, HR 0.87), REWIND (dulaglutide, HR 0.88) and SUSTAIN-6 (semaglutide 0.5 or 1.0 mg weekly, HR 0.74) for GLP-1 RA MACE benefit; CREDENCE (canagliflozin, HR 0.70) and DAPA-CKD (HR 0.61) for SGLT2i renal benefit; DAPA-HF (HR 0.74) for SGLT2i HF benefit regardless of diabetes.[9][11][10][14][13][12]
• 2019 ESC/EASD Guidelines (Cosentino and Grant, Eur Heart J 2019/2020) — the comorbidity-driven algorithm for second-line agents; the "Ten Commandments" framing of contemporary T2DM care.[3][4]

The high-yield dose table for exams

| Drug class | Exam exemplar dosing | Major benefit and pitfall | | Metformin | Start low with meals and titrate; 850 mg BD was the DPP trial dose | First-line T2DM and prediabetes (31 percent cut in progression); GI side-effects; B12 long-term; lactic acidosis rare — hold in AKI, hypoxia and per contrast protocols | | SGLT2i | Empagliflozin 10 or 25 mg OD (EMPA-REG); dapagliflozin 10 mg OD (DAPA-HF, DAPA-CKD) | CV, HF and renal benefit; genital infection; euglycaemic DKA; hold on sick days | | GLP-1 RA | Once-weekly semaglutide 0.5 or 1.0 mg (SUSTAIN-6); liraglutide, dulaglutide per product titration | MACE benefit (HR 0.74 to 0.88 across SUSTAIN-6, LEADER, REWIND); GI side-effects | | Sulfonylurea | Start low once daily, titrate (UKPDS agents: chlorpropamide, glibenclamide, glipizide) | Hypoglycaemia and weight gain — caution in the elderly | | Basal insulin | NPH or analogue once daily (twice daily for NPH), titrated to fasting glucose | Never stop suddenly in T1DM; sick-day rules | | ACE-inhibitor | Ramipril 10 mg OD (MICRO-HOPE) | 25 percent cut in MI, stroke or CV death in diabetes; renoprotection with albuminuria | | DKA insulin infusion | Fixed-rate IV insulin 0.1 U/kg/hour | Low-dose 0.05 U/kg/hour non-inferior in young children | | Hypoglycaemia rescue | Oral glucose 15 to 20 g, repeated after 10 to 15 min; severe: IV dextrose or 1 mg IM glucagon | Follow with complex carbohydrate; find the precipitant |

[15] [7] [12] [13] [10] [9] [11] [16] [17] [20] [22]

Worked stem — new T2DM with HFrEF. A 58-year-old, HbA1c 8.2 percent, BMI 34, prior HFrEF admission, eGFR 55. Beyond metformin (if eGFR allows), prioritise an SGLT2 inhibitor — dapagliflozin 10 mg daily cut worsening HF or cardiovascular death by 26 percent in HFrEF (DAPA-HF); consider a GLP-1 RA for weight and ASCVD risk; avoid a thiazolidinedione; teach sick-day rules.[12][7]

ICMR and RSSDI regional notes — the India exam lens

South Asians present earlier and at lower BMI, with higher cardiovascular risk — screen earlier and at lower thresholds.[1]

• DIPSI — the single-step non-fasting OGTT is widely used for GDM screening in India; international centres use the IADPSG 75 g OGTT criteria. Know both for the exam.[24]
• Cost-sensitive algorithms still start with metformin and lifestyle, and add an SGLT2i or GLP-1 RA when ASCVD, HF or CKD dominate, if affordable and available.
• Public-health priorities: the obesity transition, urban diets, foot-care pathways and retinopathy screening camps.[1]

Controversies worth a one-liner: how low to push HbA1c in the elderly (hypoglycaemia harm); early combination versus stepwise addition; insulin first versus a GLP-1 RA for high HbA1c without catabolism; CGM access expanding beyond type 1.[3]

How diabetics come to harm — the preventable list

These are the deaths and disasters the annual review exists to prevent.[1]

• The unrecognised T1DM sent home on metformin who returns in DKA — type the diabetes before you treat it.[1]
• The insulin-treated patient who stopped basal insulin because they "weren't eating" and landed in DKA — sick-day rules save lives.[1]
• The elderly patient on a sulfonylurea driven to a severe hypo by an aggressive HbA1c target — de-intensify in the frail.[3]
• The patient on an SGLT2i in DKA with a near-normal glucose — check ketones in any unwell patient on the drug.[7]
• The silent MI missed because autonomic neuropathy blunted the pain — troponin and ECG in any chest pain or dyspnoea.[1]
• The foot ulcer that became an amputation — examine the feet every year, refer early.[1]
• The proliferative retinopathy that bled because screening lapsed — annual retinal photography, no exceptions.[1]
• The pregnant patient with HbA1c over 6.5 percent at conception — pre-conception counselling prevents congenital anomaly and neonatal hypoglycaemia.[1]

Red flags

• DKA — polyuria, vomiting, Kussmaul breathing, abdominal pain, ketones over 3 mmol/L with pH under 7.3. Bundle: fluids first, fixed-rate insulin 0.1 units/kg/hour, replace potassium, find and treat the precipitant.
• HHS — glucose over 33 mmol/L (600 mg/dL), osmolality over 320 mOsm/kg, minimal ketones in an older T2DM with infection, stroke or ACS; aggressive volume repletion plus insulin; mortality far higher than DKA.[23][19][25]
• Severe hypoglycaemia — unconscious, fitting or unsafe swallow; 10 percent IV dextrose or IM glucagon 1 mg; find the precipitant.[22]
• Euglycaemic DKA — patient on an SGLT2i, pregnancy, partial treatment, alcohol; check ketones in any unwell patient on an SGLT2i.
• Sudden monocular visual loss — proliferative retinopathy with vitreous haemorrhage; urgent ophthalmology and panretinal photocoagulation.
• Sudden hot, swollen, deformed foot with neuropathy and no fever — Charcot neuroarthropathy; offload in a total contact cast; do not mistake for infection.
• Painful ulcer with cellulitis, crepitus, foul discharge or systemic sepsis — diabetic foot infection; urgent imaging, IV antibiotics, surgical review, possible amputation.
• Acute coronary syndrome or stroke — silent MI is common; high-sensitivity troponin and ECG in any chest pain or dyspnoea.
• New macroproteinuria or rapidly falling eGFR — nephrology referral; consider non-diabetic disease and add an SGLT2i and an ACE-inhibitor.
• Pregnancy with HbA1c over 6.5 percent at conception — pre-conception counselling, tight control, neonatal hypoglycaemia monitoring after delivery.
• Missed insulin doses — high DKA risk; never skip basal insulin during illness.[1]

Exam pearls — the lines that earn marks

• Diagnostic thresholds: HbA1c over 6.5 percent, fasting over 7.0 mmol/L (126 mg/dL), 2-hour 75 g OGTT over 11.1 mmol/L (200 mg/dL), or a random glucose over 11.1 mmol/L (200 mg/dL) with symptoms.[18][26]
• Type 1 versus type 2: thin, young, ketosis-prone, autoimmune, insulin-dependent equals T1DM; overweight, insulin-resistant, family history equals T2DM; LADA mixes both; MODY is autosomal dominant, lean, young and antibody-negative.
• First-line T2DM: lifestyle plus metformin — UKPDS 34 cut all-cause mortality 36 percent in overweight T2DM; 850 mg BD was the DPP dose.[8][15]
• Cardiovascular protection: SGLT2i for HF or CKD (DAPA-HF, DAPA-CKD, CREDENCE); GLP-1 RA for ASCVD or weight loss (LEADER, SUSTAIN-6, REWIND) — on top of metformin.[12][13][9]
• Tight glycaemia in T1DM (DCCT and EDIC): retinopathy onset cut 76 percent; metabolic memory cut cardiovascular events 42 percent over 17 years.[6][5]
• Metformin in overweight T2DM (UKPDS 34): cuts diabetes-related endpoints, diabetes-related death and all-cause mortality — a unique result.[8]
• HbA1c target: near 7 percent for most adults (UKPDS 7.0 vs 7.9); loosen for the frail and hypoglycaemia-prone.[16]
• Sick-day rules: never stop insulin, monitor ketones, seek help early.
• Annual review: HbA1c, blood pressure, lipids, UACR, eGFR, retinal screening, foot exam, weight, smoking.
• Foot risk stratification: neuropathy plus ischaemia plus deformity plus prior ulcer means high risk.
• Pregnancy: screen with a 75 g OGTT at 24 to 28 weeks using IADPSG criteria; postpartum re-screening is mandatory.[24]
• SGLT2i and euglycaemic DKA: stop during illness, fasting and surgery.[21]
• Driving regulations (DVLA or equivalent): insulin-treated patients check glucose before driving, hold a Group 1 or 2 licence by criteria, and in the UK require stable glycaemia and hypoglycaemia-awareness testing.[1]

The mantra

Lifestyle and metformin first; SGLT2i for the heart and the kidney, GLP-1 for the vessels and the weight; insulin when the beta cell is gone — and never stop the basal when they are ill.[1][8]

Ward-round test — four stems, thirty seconds each

Stem 1 — the thin 24-year-old with pear-drop breath (answer)

Model: This is diabetic ketoacidosis on new type 1 diabetes. Confirm with venous gas (pH under 7.3, bicarbonate under 15 mEq/L) and ketone testing. Bundle in order: isotonic saline to restore the deficit, check potassium (replace before and during insulin), then fixed-rate intravenous insulin 0.1 units/kg/hour (0.05 non-inferior in young children), move to glucose-containing fluid as the glucose falls, find the precipitant, and watch for cerebral oedema. Send anti-GAD and C-peptide to confirm T1DM once she is stable.[19][20]

Stem 2 — the 58-year-old with HbA1c 8.2 percent and a recent HFrEF admission (answer)

Model: Add an SGLT2 inhibitor (empagliflozin or dapagliflozin) — proven to cut HF hospitalisation and cardiovascular death (EMPA-REG, DAPA-HF). Consider a GLP-1 RA for weight and ASCVD risk. Avoid a thiazolidinedione (fluid retention and HF). Teach sick-day rules — hold the SGLT2i during illness to prevent euglycaemic DKA.[7][12][21]

Stem 3 — the 72-year-old on gliclazide, HbA1c 6.2 percent, three hypos a week (answer)

Frail, lives alone, asymptomatic. What do you change, and why? Model: This is over-treatment, not success. De-intensify: stop or reduce the sulfonylurea, loosen the HbA1c target to 7.5 to 8.5 percent, and prefer a low-hypoglycaemia agent (DPP-4i, or a carefully chosen SGLT2i/GLP-1 RA). The harm in the elderly diabetic is hypoglycaemia — falls, confusion, arrhythmia — not a slightly higher glucose.[3]

Stem 4 — the 32-year-old 'type 2' on metformin, losing weight, went ketotic last week (answer)

Thin, anti-GAD positive, C-peptide low-normal. What is the diagnosis and the right treatment? Model: This is LADA — latent autoimmune diabetes of adults. Stop chasing a type-2-only pathway and start insulin (basal-bolus), which preserves residual beta-cell function and prevents the next DKA. The classic trap is labelling a non-obese young adult as type 2 and stranding them on metformin until they crash.[1]

References

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2. [2]American Diabetes Association. 6. Glycemic Targets: Standards of Medical Care in Diabetes-2019 Diabetes Care, 2019.PMID 30559232
3. [3]Cosentino F, Grant PJ, Aboyans V, et al. 2019 ESC Guidelines on diabetes, pre-diabetes, and cardiovascular diseases developed in collaboration with the EASD Eur Heart J, 2020.PMID 31497854
4. [4]Grant PJ, Cosentino F The 2019 ESC Guidelines on diabetes, pre-diabetes, and cardiovascular diseases developed in collaboration with the EASD: New features and the ‘Ten Commandments’ of the 2019 Guidelines are discussed by Professor Peter J. Grant and Professor Francesco Cosentino, the Task Force chairmen Eur Heart J, 2019.PMID 31608951
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16. [16]UK Prospective Diabetes Study (UKPDS) Group. Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33) Lancet, 1998.PMID 9742976
17. [17]Heart Outcomes Prevention Evaluation Study Investigators. Effects of ramipril on cardiovascular and microvascular outcomes in people with diabetes mellitus: results of the HOPE study and MICRO-HOPE substudy Lancet, 2000.PMID 10675071
18. [18]Duong KNC, Chaiyakunapruk N, et al. Comparison of diagnostic accuracy for diabetes diagnosis: a systematic review and network meta-analysis Front Med (Lausanne), 2023.PMID 36760402
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24. [24]Zhao KS, Yuan CL, et al. Neutrophil count and urinary glucose as early predictors of gestational diabetes mellitus in nulliparous women of advanced maternal age: a retrospective cohort study Front Endocrinol (Lausanne), 2026.PMID 42039122
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