USMLE/COMLEX 3 - Hypertension Definitions & Etiologies

Here are key facts for USMLE Step 3 & COMLEX-USA Level 3 from the Hypertension Overview tutorial, as well as points of interest at the end of this document that are not directly addressed in this tutorial but should help you prepare for the boards. See the tutorial notes for further details and relevant links.

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• Normal: <120/<80 mmHg
• Elevated: 120–129/<80 mmHg
• Stage 1 HTN: 130–139 or 80–89 mmHg
• Stage 2 HTN: ≥140 or ≥90 mmHg
• BP classification guides pharmacologic vs lifestyle intervention.

• 90–95% of cases; multifactorial.
• Risk factors: obesity, high sodium intake, low potassium, sedentary lifestyle, genetics, stress.

• New-onset HTN <30 years or >55 years
• Severe/resistant HTN (>3 medications including diuretic)
• End-organ damage out of proportion to BP

• Renovascular disease: Abdominal bruit, recurrent flash pulmonary edema
• Primary aldosteronism: HTN + hypokalemia
• OSA: Daytime sleepiness, snoring, obesity
• Pheochromocytoma: Episodic HTN, palpitations, headache
• Cushing syndrome: Central obesity, skin changes, glucose intolerance
• Coarctation of the aorta: BP discrepancy in arms/legs, diminished femoral pulses
• Drugs: NSAIDs, steroids, decongestants, OCPs, stimulants

• Assess for secondary causes
• Order: CMP, lipid panel, urinalysis, ECG, fasting glucose/A1c
• Consider: TSH, aldosterone-renin ratio, metanephrines, renal imaging if indicated

• DASH diet
• Weight loss
• Low sodium (<1500 mg/day if possible)
• Exercise: ≥150 min/week
• Limit alcohol, quit smoking

• ACE inhibitors/ARBs, thiazide diuretics, calcium channel blockers
• Black patients: thiazide or CCB preferred
• CKD/proteinuria: ACEi or ARB

• General target: <130/80 mmHg
• Elderly: individualize based on frailty, fall risk, and tolerability

• ≥180/≥120 mmHg + end-organ damage (e.g., encephalopathy, MI, stroke, AKI)
• Treat with IV antihypertensives (e.g., labetalol, nicardipine)
• Reduce MAP by no more than 25% in first hour

• Same BP range, no end-organ damage
• Treat with oral agents, follow-up within 24–72 hours

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• Uncontrolled BP on ≥3 drugs, including a diuretic
• Rule out: poor adherence, white coat effect, drug causes, secondary HTN
• Consider: ambulatory BP monitoring

• Confirm diagnosis with home or ambulatory BP monitoring
• White coat: elevated in clinic only
• Masked: normal in clinic, elevated outside

• More common in African Americans, elderly, and post-menopausal women
• Respond well to sodium reduction and thiazides

• First-line: labetalol, nifedipine, methyldopa
• Avoid: ACEi, ARB, diuretics
• Gestational HTN can progress to pre-eclampsia → monitor closely

• Isolated systolic HTN in elderly: treat to prevent stroke, HF, CKD
• BP post-stroke: lower gradually if severe; permissive HTN sometimes appropriate acutely
• Post-MI: beta blockers + ACE inhibitors for BP and mortality benefit
• Diabetics: target <130/80 mmHg

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• If patient presents with hypertensive emergency:
• Admit to ICU
• Start IV antihypertensives
• Monitor urine output, neuro status
• Order: Head CT (if neurologic signs), ECG, troponin, creatinine, urinalysis

• >20 with elevated aldosterone suggests primary aldosteronism

• Initial: duplex Doppler ultrasound
• Best: CT angiogram or MR angiography
• Definitive: renal arteriography

• Start with ACEi or ARB, even in normotensive patients with proteinuria
• Monitor for hyperkalemia and rising creatinine

• Recheck BP in 1 month after starting therapy
• Assess for side effects, med adherence, and organ damage at follow-ups