Family Medicine · Year 3 · from Family Medicine
Case 2: Resistant Hypertension
Patient Demographics
- Age: 58 years old
- Sex: Female
- Occupation: Restaurant manager
Chief Complaint
"My blood pressure is still high even though I'm taking three medications."
History of Present Illness
Mrs. Angela Thompson is a 58-year-old woman with a 12-year history of hypertension who presents for follow-up. Despite being on three antihypertensive medications, her BP remains elevated. Home BP readings average 158/95 mmHg. She reports taking her medications regularly but admits she sometimes forgets the evening dose. She consumes a high-sodium diet due to working in a restaurant and tasting food frequently. She reports bilateral leg swelling and occasional headaches.
She denies chest pain, shortness of breath, or visual changes. She has gained 15 pounds over the past year.
Past Medical History
- Hypertension (12 years)
- Obesity
- Sleep apnea, diagnosed 3 years ago, not using CPAP ("too uncomfortable")
- Depression
Current Medications
- Amlodipine 10mg daily
- Lisinopril 40mg daily
- Hydrochlorothiazide 25mg daily
- Sertraline 100mg daily
- Ibuprofen 400mg 2-3 times daily for knee pain
Family History
- Father: Hypertension, died of heart attack age 65
- Mother: Hypertension, stroke
Social History
- Never smoker
- Alcohol: 1 glass of wine nightly
- Works long hours, high stress
- Lives with husband
Physical Examination
- Vital Signs: BP 162/98 mmHg (right), 160/96 (left), HR 72, BMI 36
- General: Obese woman, appears fatigued
- Neck: Obese neck, difficult to assess thyroid
- Cardiovascular: Regular rhythm, S4 gallop, no murmurs
- Lungs: Clear
- Abdomen: Obese, no bruits auscultated
- Extremities: 2+ bilateral pitting edema
Assessment and Diagnosis
- Resistant hypertension - Uncontrolled on 3 medications including a diuretic
- Contributing factors identified:
- Medication non-adherence (missed evening doses)
- High sodium intake
- NSAID use (ibuprofen)
- Untreated sleep apnea
- Obesity
- Possible secondary hypertension - Consider workup
- Target organ damage - S4 gallop suggests LVH
Outpatient Workup
- Basic metabolic panel: K+ 3.2 mEq/L (low), Creatinine 1.1
- Aldosterone: 18 ng/dL, Plasma renin activity: 0.3 ng/mL/hr
- Aldosterone-to-renin ratio: 60 (elevated, concerning for primary aldosteronism)
- TSH: Normal
- Urinalysis: No proteinuria
- ECG: LVH by voltage criteria
- 24-hour urine sodium: 5200 mg (very high intake)
- Renal ultrasound with Doppler: Normal kidney size, no renal artery stenosis
Management Plan
Address Modifiable Factors:
- NSAID discontinuation - Stop ibuprofen, causes sodium retention and reduces antihypertensive efficacy
- Alternative: Acetaminophen for knee pain
- Sleep apnea treatment - Strongly encourage CPAP use, discuss mask options
- Sodium restriction - Reduce intake to <2000 mg/day, work with nutritionist
- Medication adherence - Simplify regimen, consider combination pill
- Weight loss counseling - Target 10% weight loss
Medication Adjustment:
- Given low potassium and elevated aldosterone-to-renin ratio:
- Add spironolactone 25mg daily (effective in resistant hypertension, addresses possible aldosteronism)
- Continue current medications
- Recheck potassium in 1 week
Further Workup:
- Refer to hypertension specialist/endocrinology for confirmatory testing for primary aldosteronism
- Consider CT adrenals if aldosteronism confirmed
- Echocardiogram to assess LVH and cardiac function
Follow-Up
- Return in 2 weeks to assess BP and potassium
- Phone check in 1 week for potassium level
- Specialist referral for aldosteronism workup
Teaching Points
- Definition of resistant hypertension: BP above goal despite 3 medications at optimal doses, including a diuretic. Prevalence is 10-15% of treated hypertensives.
- Pseudo-resistance causes:
- White coat effect
- Medication non-adherence
- Improper BP technique
- Suboptimal medication dosing
- Contributing factors:
- High sodium intake
- NSAIDs (very common culprit)
- Untreated sleep apnea
- Obesity
- Excess alcohol
- Secondary hypertension workup: Consider in resistant hypertension. Primary aldosteronism is the most common secondary cause (5-10% of hypertensives). Screening with aldosterone-to-renin ratio; if elevated (>30), confirmatory testing indicated.
- Spironolactone: Effective fourth-line agent for resistant hypertension, particularly if aldosteronism suspected. Monitor potassium closely.