Residency · Residency · Internal Medicine

Hypertension Management in the Outpatient Setting

Introduction

Hypertension affects nearly half of all US adults and remains the single largest modifiable risk factor for cardiovascular disease, stroke, and chronic kidney disease. The 2017 ACC/AHA guidelines redefined hypertension as blood pressure at or above 130/80 mmHg, substantially expanding the population requiring intervention. Internal medicine residents must master accurate measurement, risk stratification, and individualized pharmacotherapy.

Blood Pressure Measurement

Proper Technique

• Seated with back supported, feet flat on the floor, arm supported at heart level
• Appropriate cuff size: bladder encircling at least 80% of the upper arm circumference
• No caffeine, exercise, or smoking for 30 minutes prior
• Allow 5 minutes of quiet rest before measurement
• Average of 2-3 readings taken 1-2 minutes apart

Out-of-Office Measurement

• Ambulatory blood pressure monitoring (ABPM): gold standard for confirming hypertension and detecting white-coat or masked hypertension
• Home blood pressure monitoring (HBPM): morning and evening readings over 7 days; discard first day, average remaining values
• White-coat hypertension (elevated office BP, normal out-of-office): prevalence 15-30%; associated with intermediate cardiovascular risk
• Masked hypertension (normal office BP, elevated out-of-office): prevalence 10-15%; carries risk similar to sustained hypertension

Classification (2017 ACC/AHA)

Secondary Hypertension Screening

• Consider when onset is before age 30, resistant hypertension, abrupt worsening, or suggestive clinical features
• Primary aldosteronism: aldosterone-to-renin ratio (most common secondary cause)
• Renovascular disease: renal artery duplex ultrasound or CT angiography
• Pheochromocytoma: plasma free metanephrines
• Obstructive sleep apnea: STOP-BANG questionnaire, polysomnography
• Cushing syndrome: overnight dexamethasone suppression test or 24-hour urine cortisol
• Thyroid disease: TSH

Nonpharmacologic Interventions

• DASH diet: rich in fruits, vegetables, whole grains, low-fat dairy; reduces SBP by 8-14 mmHg
• Sodium restriction: target < 1500 mg/day; reduces SBP by 5-6 mmHg
• Aerobic exercise: 150 minutes/week moderate intensity; reduces SBP by 5-8 mmHg
• Weight loss: 1 mmHg reduction per kg lost
• Alcohol moderation: limit to 1 drink/day (women), 2 drinks/day (men)
• Potassium supplementation: 3500-5000 mg/day from dietary sources

Pharmacotherapy

First-Line Agents

• ACE inhibitors / ARBs: preferred in diabetes, CKD with proteinuria, heart failure with reduced ejection fraction
• Calcium channel blockers (amlodipine, nifedipine): effective across demographics; preferred in Black patients as monotherapy
• Thiazide/thiazide-like diuretics (chlorthalidone, indapamide): chlorthalidone preferred over HCTZ (longer half-life, stronger evidence)

Special Populations

• Black patients: initiate with CCB or thiazide; dual therapy often needed early
• CKD with proteinuria: ACEi or ARB mandatory; switch to loop diuretic if eGFR < 30
• Heart failure (HFrEF): ACEi/ARB (or ARNI), beta-blocker, MRA, and diuretic
• Pregnancy: labetalol, nifedipine, or methyldopa; avoid ACEi/ARB (teratogenic)
• Post-stroke: ACEi + thiazide combination (PROGRESS trial)

Resistant Hypertension

• Defined as BP above goal despite 3 optimally dosed agents including a diuretic
• Confirm adherence (pill counts, liquid chromatography-mass spectrometry)
• Add spironolactone 25-50 mg daily (PATHWAY-2 trial): most effective fourth-line agent
• Rule out secondary causes and optimize diuretic therapy

Blood Pressure Targets

• General population: < 130/80 mmHg (ACC/AHA 2017)
• SPRINT trial: intensive target (SBP < 120) reduced major cardiovascular events by 25% and all-cause mortality by 27%
• Elderly (>= 65 years): individualize; SPRINT included ambulatory patients >= 75 and showed benefit
• Diabetes: < 130/80 mmHg; evidence strongest for SBP < 130 (ACCORD BP showed stroke benefit)

Follow-Up and Monitoring

• Recheck BP at 1-month intervals after initiating or adjusting therapy
• Monitor electrolytes and creatinine within 2-4 weeks of starting ACEi/ARB or diuretic
• Once at goal, follow-up every 3-6 months
• Assess for medication side effects, adherence barriers, and lifestyle modifications at each visit

Key Clinical Pearls

• Always confirm the diagnosis with out-of-office measurements before initiating lifelong pharmacotherapy
• Chlorthalidone is preferred over HCTZ based on superior 24-hour BP lowering and cardiovascular outcome data
• Spironolactone is the most effective add-on agent for resistant hypertension
• Single-pill combinations improve adherence and should be considered early, especially in Stage 2 hypertension

References

1. Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA Guideline for Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults. Hypertension. 2018;71(6):e13-e115.
2. SPRINT Research Group. A Randomized Trial of Intensive versus Standard Blood-Pressure Control. N Engl J Med. 2015;373(22):2103-2116.
3. Williams B, MacDonald TM, Morant S, et al. Spironolactone versus Placebo, Bisoprolol, and Doxazosin to Determine the Optimal Treatment for Drug-Resistant Hypertension (PATHWAY-2). Lancet. 2015;386(10008):2059-2068.
4. Muntner P, Shimbo D, Carey RM, et al. Measurement of Blood Pressure in Humans: A Scientific Statement from the AHA. Hypertension. 2019;73(5):e35-e66.

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