Secondary Hypertension Suspicion by Age
Secondary hypertension should be suspected in patients younger than 30 years of age with elevated blood pressure, though it can occur at any age depending on the specific underlying cause. 1
Age-Based Suspicion Thresholds
Young Adults (<30 years)
- Onset before age 30 is a key clinical clue warranting thorough evaluation for secondary causes 1
- However, primary hypertension can manifest at younger ages, particularly in Black patients, so age alone is not definitive 1
- In children and adolescents, renal parenchymal disease and coarctation of the aorta are the most common secondary causes 2
Middle-Aged Adults (30-50 years)
- Onset of hypertension before age 20 or after age 50 suggests secondary causes 3
- The 30-50 age range represents the typical onset period for primary hypertension, making secondary causes less likely unless other clinical features are present 3
Older Adults (>50-65 years)
- New-onset hypertension after age 50-65 years should raise suspicion for atherosclerotic renovascular disease 3, 2
- In adults ≥65 years, atherosclerotic renal artery stenosis, renal failure, and hypothyroidism are common secondary causes 2
Clinical Context Beyond Age
Age alone is insufficient—secondary hypertension should be suspected regardless of age when these features are present:
High-Risk Clinical Presentations
- Resistant hypertension (BP >140/90 mmHg despite optimal doses of ≥3 drugs including a diuretic) 1, 4
- Severe or accelerated/malignant hypertension with grade III-IV retinopathy 1, 3, 2
- Abrupt onset or sudden worsening of previously controlled hypertension 1, 2
- Target organ damage disproportionate to duration or severity of hypertension 1
Specific Physical Examination Findings
- For patients ≤30 years with elevated brachial BP, measure thigh BP—if lower than arm pressures, consider coarctation of the aorta 1
- Abdominal bruits suggest renovascular disease 3
- Decreased or delayed femoral pulses indicate coarctation 3
Laboratory Red Flags
- Unprovoked hypokalemia (primary aldosteronism) 1, 3
- Serum creatinine increase ≥50% within one week of starting ACE inhibitor/ARB (renovascular disease) 2
Important Caveats
- Primary aldosteronism affects 8-20% of resistant hypertension cases and can occur at any age 4
- Obstructive sleep apnea is present in 25-50% of resistant hypertension and is age-independent 4
- Some secondary causes like fibromuscular dysplasia typically affect younger women (<40 years), while atherosclerotic renovascular disease affects older adults (>60 years) 1
- Even after treating secondary causes, many patients require ongoing antihypertensive therapy due to concomitant essential hypertension or irreversible vascular remodeling 5