Management of Secondary Hypertension
Secondary hypertension should be managed by identifying and treating the underlying cause while optimizing antihypertensive therapy with medications such as ACE inhibitors, ARBs, calcium channel blockers, diuretics, beta-blockers, and mineralocorticoid receptor antagonists. 1
Identification and Evaluation
Secondary hypertension accounts for approximately 10% of all hypertension cases and is characterized by an identifiable underlying cause that can potentially be treated or cured 1. Screening is recommended for patients with:
- Early onset hypertension (before age 30)
- Severe or resistant hypertension
- Sudden deterioration in previously controlled BP
- Target organ damage disproportionate to hypertension duration
- Specific clinical features (hypokalemia, abdominal bruits)
Essential Screening Tests
- Blood tests: Fasting glucose, lipids, electrolytes, creatinine, eGFR, TSH, hemoglobin, calcium, uric acid 1
- Urine tests: Urinalysis, albumin-to-creatinine ratio 1
- 12-lead ECG: To detect atrial fibrillation, left ventricular hypertrophy, and ischemic heart disease 1
Specific Tests for Secondary Causes
- Plasma aldosterone/renin ratio for primary aldosteronism
- Renal ultrasound for renal parenchymal disease
- Renal Duplex Doppler for renovascular disease
- Sleep studies for obstructive sleep apnea 1
Treatment Approach
1. Cause-Specific Management
Primary Aldosteronism:
- Unilateral: Adrenalectomy
- Bilateral: Mineralocorticoid receptor antagonists (spironolactone or eplerenone) 1
Renovascular Disease:
- Fibromuscular dysplasia: Percutaneous transluminal renal angioplasty without stenting
- Atherosclerotic renal artery stenosis: Medical therapy (lifestyle modifications, low-dose aspirin, statin, antihypertensives) 1
Obstructive Sleep Apnea:
- Weight loss
- CPAP therapy
- Mandibular advancement devices 1
2. Pharmacological Management
While addressing the underlying cause, antihypertensive medications are typically needed:
First-line options:
For resistant hypertension:
- Add mineralocorticoid receptor antagonists (spironolactone or eplerenone)
- Consider beta-blockers to counteract sympathetic activation 1
3. Lifestyle Modifications
Even with secondary hypertension, lifestyle changes remain important:
- Weight loss (aim for 5-10% reduction initially) 1
- Sodium restriction (<1,500 mg/day) 1
- Regular physical activity (150+ minutes/week of moderate-intensity exercise) 1
- DASH diet pattern (high fiber, low fat) 1
- Alcohol moderation (no more than 1-2 drinks per day) 1
Special Considerations
Resistant Hypertension
Defined as BP >140/90 mmHg despite three optimal-dose medications including a diuretic:
- Optimize current regimen by maximizing diuretic therapy
- Use loop diuretics for eGFR <30 ml/min/1.73m²
- Add fourth-line agent (spironolactone, amiloride, doxazosin, eplerenone, clonidine, or beta-blockers)
- Consider referral for renal denervation in specialized centers 1
Target BP and Monitoring
- Target BP should be 120-129 mmHg systolic if tolerated 1
- Regular BP monitoring (home and office)
- Periodic assessment of target organ damage
- Monitor for medication side effects, particularly hyperkalemia and renal function deterioration 1
Common Pitfalls to Avoid
Failure to screen appropriately: Secondary hypertension is often underrecognized, especially in patients with resistant hypertension where prevalence may be as high as 50% 4
Abrupt discontinuation of antihypertensives: Continue medications while investigating the underlying cause to prevent dangerous BP fluctuations
Missing drug-induced hypertension: Always review all medications, including OTC drugs and supplements 5
Inadequate follow-up: Even after treating the underlying cause, continued monitoring is essential as hypertension may persist or recur
Overlooking comorbidities: Address metabolic abnormalities, such as statin therapy and glycemic control in diabetes, which are crucial for reducing cardiovascular risk 1