What information about hypertension should I know for the MCCQE‑1 exam?

Hypertension: Essential Knowledge for MCCQE1

Definition and Classification

Hypertension is defined as persistent systolic blood pressure (SBP) ≥130 mmHg or diastolic blood pressure (DBP) ≥80 mmHg. 1

Blood Pressure Categories

• Optimal: <120/<80 mmHg 1
• Normal: 120-129/80-84 mmHg 1
• High normal (Elevated): 130-139/85-89 mmHg 1
• Grade 1 (Stage 1) hypertension: 140-159/90-99 mmHg 1
• Grade 2 (Stage 2) hypertension: 160-179/100-109 mmHg 1
• Grade 3 (Stage 3) hypertension: ≥180/≥110 mmHg 1
• Isolated systolic hypertension: ≥140/<90 mmHg 1

Diagnosis and Confirmation

Always confirm hypertension with out-of-office blood pressure measurements before initiating lifelong therapy. 2, 3

Diagnostic Thresholds

• Office/clinic BP: ≥130/80 mmHg 1
• Home BP monitoring: ≥135/85 mmHg confirms hypertension 4, 2
• 24-hour ambulatory BP: ≥130/80 mmHg (daytime ≥135/85 mmHg, nighttime ≥120/75 mmHg) 4

White Coat vs. Masked Hypertension

• White coat hypertension: Office BP ≥130/80 mmHg with out-of-office BP <130/80 mmHg; occurs in 15-20% of stage 1 hypertension cases and carries cardiovascular risk similar to normotension 1, 2
• Masked hypertension: Normal office BP but elevated home/ambulatory BP; nearly doubles cardiovascular event risk 4

Initial Evaluation

History and Physical Examination

Look for specific features suggesting primary versus secondary hypertension: 1

Primary hypertension indicators:

• Gradual BP increase over time 1
• Family history of hypertension 1
• Lifestyle factors: weight gain, high sodium diet, decreased physical activity, excessive alcohol 1

Secondary hypertension red flags:

• Age <40 years at onset 2
• BP lability with episodic pallor/dizziness (pheochromocytoma) 1
• Snoring, hypersomnolence (obstructive sleep apnea) 1
• Muscle cramps, weakness (hypokalemia from primary aldosteronism) 1
• Weight loss, palpitations, heat intolerance (hyperthyroidism) 1
• Central obesity, facial rounding, easy bruising (Cushing's syndrome) 1
• Medication/substance use: NSAIDs, cocaine, amphetamines, oral contraceptives, decongestants 1

Essential Laboratory Tests

Obtain these baseline investigations for all newly diagnosed hypertensive patients: 1

• Fasting blood glucose and HbA1c 1, 2
• Complete blood count 1
• Lipid profile 1
• Serum creatinine with eGFR 1
• Serum sodium, potassium, calcium 1
• Thyroid-stimulating hormone 1, 2
• Urinalysis 1
• Electrocardiogram 1, 2
• Optional: Echocardiogram, uric acid, urinary albumin-to-creatinine ratio 1

Treatment Thresholds and Goals

When to Initiate Pharmacological Therapy

Start antihypertensive medication immediately if: 1, 2

• Stage 2 hypertension (≥160/100 mmHg) 1
• 10-year ASCVD risk ≥10% 1, 2
• Diabetes mellitus 1
• Chronic kidney disease 1
• Evidence of target-organ damage 1

For stage 1 hypertension (130-139/80-89 mmHg) without high-risk features, attempt intensive lifestyle modifications for 3-6 months before starting medication. 2

Blood Pressure Targets

• Primary target: <130/80 mmHg for most adults 1, 4
• Minimum acceptable: <140/90 mmHg 1
• Optimal target if tolerated: 120-129 mmHg systolic 1
• Elderly (≥65 years): SBP <130 mmHg 5
• Diabetes or CKD: <130/80 mmHg 1, 4

Lifestyle Modifications

Lifestyle changes are first-line therapy and provide additive BP reductions of 10-20 mmHg. 1, 5

Evidence-Based Interventions

• Sodium restriction to <2g/day (ideally <1500mg): Reduces SBP by 5-10 mmHg 1, 4, 5
• DASH diet: Reduces BP by 11.4/5.5 mmHg (systolic/diastolic) 1, 4, 5
• Weight loss (10 kg): Reduces BP by 6.0/4.6 mmHg 1, 4
• Aerobic exercise (90-150 min/week): Reduces BP by 4/3 mmHg 1, 4, 5
• Alcohol limitation: ≤2 drinks/day for men, ≤1 drink/day for women 1, 4
• Potassium supplementation: 3500-5000 mg/day 1

Pharmacological Treatment

First-Line Antihypertensive Agents

The four first-line drug classes are thiazide/thiazide-like diuretics, ACE inhibitors, ARBs, and calcium channel blockers. 5, 6, 7

Initial Drug Selection by Patient Population

Non-Black patients:

• Preferred: ACE inhibitor or ARB 4, 6
• Alternative: Calcium channel blocker or thiazide diuretic 6

Black patients:

• Preferred: Calcium channel blocker or thiazide diuretic 4, 6
• Rationale: More effective than ACE inhibitors/ARBs in this population 4

Diabetes with albuminuria:

• Preferred: ACE inhibitor or ARB 1, 6

Chronic kidney disease:

• Preferred: ACE inhibitor or ARB to improve kidney outcomes 1, 6

Heart failure with reduced ejection fraction:

• Preferred: Guideline-directed medical therapy beta-blockers (carvedilol, metoprolol succinate, bisoprolol) plus ACE inhibitor/ARB 1

Post-MI or stable ischemic heart disease:

• Preferred: Beta-blocker plus ACE inhibitor/ARB 1

Specific Drug Considerations

Thiazide-like diuretics:

• Chlorthalidone 12.5-25mg daily is preferred over hydrochlorothiazide due to longer duration of action (24-72 hours vs 6-12 hours) and superior cardiovascular outcomes in ALLHAT trial 4, 8

Beta-blockers:

• Not recommended as first-line for uncomplicated hypertension unless compelling indications exist (angina, post-MI, heart failure, atrial fibrillation) 1, 8
• Less effective than other classes for stroke prevention 1

Combination Therapy Strategy

For stage 2 hypertension (≥160/100 mmHg), initiate dual therapy immediately with two agents from different classes. 1, 4

Preferred two-drug combinations: 4, 8

• ACE inhibitor/ARB + calcium channel blocker
• ACE inhibitor/ARB + thiazide diuretic
• Calcium channel blocker + thiazide diuretic

Standard triple therapy (when dual therapy fails): 4, 8

• ACE inhibitor/ARB + calcium channel blocker + thiazide diuretic

Fourth-line agent for resistant hypertension:

• Spironolactone 25-50mg daily is the preferred fourth-line agent, providing additional BP reductions of 20-25/10-12 mmHg 4, 8

Critical Drug Combinations to Avoid

• Never combine ACE inhibitor with ARB (dual RAS blockade increases hyperkalemia and acute kidney injury without cardiovascular benefit) 1, 4, 8
• Avoid non-dihydropyridine calcium channel blockers (diltiazem, verapamil) in heart failure with reduced ejection fraction due to negative inotropic effects 1, 8

Monitoring and Follow-Up

Reassess BP within 1 month after initiating or modifying therapy. 4

Achieve target BP within 3 months of treatment initiation. 4, 8

Monitor serum potassium and creatinine 2-4 weeks after starting ACE inhibitor, ARB, or diuretic. 4, 8

Resistant Hypertension

Defined as BP ≥140/90 mmHg despite three antihypertensive agents (including a diuretic) at optimal doses. 8

Evaluation Steps Before Adding Fourth Agent

1. Verify medication adherence (most common cause of apparent resistance) 4, 8
2. Confirm with home BP or 24-hour ambulatory monitoring 4
3. Review interfering medications: NSAIDs, decongestants, oral contraceptives, systemic corticosteroids, stimulants 4, 8
4. Screen for secondary causes: Primary aldosteronism, renal artery stenosis, obstructive sleep apnea, pheochromocytoma 4, 8

Management of Resistant Hypertension

• Optimize diuretic therapy: Replace hydrochlorothiazide with chlorthalidone for superior 24-hour BP control 8
• Add spironolactone 25-50mg daily as preferred fourth agent 4, 8
• Consider referral to hypertension specialist if BP remains ≥160/100 mmHg despite four-drug therapy 8

Special Populations

Elderly Patients (≥65 years)

• Target SBP <130 mmHg if tolerated 5
• Initiate treatment with low doses and uptitrate slowly 1
• Assess for orthostatic hypotension (decline >20 mmHg SBP or >10 mmHg DBP after 1 minute standing) 1

Pregnancy

• This is a specialized topic requiring separate detailed guidelines beyond MCCQE1 scope 1

Chronic Kidney Disease

• ACE inhibitor or ARB is first-line to improve kidney outcomes 1, 6
• Target BP <130/80 mmHg for additional renal protection 4

Common Pitfalls to Avoid

• Do not diagnose hypertension based solely on office readings without out-of-office confirmation 2, 3
• Do not delay treatment intensification when BP remains uncontrolled; adjust therapy within 2-4 weeks 4, 8
• Do not overlook secondary hypertension in young patients (<40 years) or those with resistant hypertension 1, 2
• Do not use beta-blockers as first-line unless compelling indications exist 1, 8
• Do not escalate a single drug to maximum dose before adding a second agent from a different class 4, 8

Prognosis and Cardiovascular Risk

A 10 mmHg reduction in SBP decreases cardiovascular events by 20-30%. 5

Hypertension increases risk of: 1, 5, 7

• Coronary heart disease and myocardial infarction
• Heart failure
• Stroke and transient ischemic attacks
• Chronic kidney disease and renal failure
• Peripheral arterial disease
• Cognitive decline and dementia

Despite effective treatments, only 44% of US adults with hypertension achieve BP control <140/90 mmHg. 5