Signs/symptomsPossible secondary hypertension causeDiagnostic test options
Arm to leg systolic blood pressure difference > 20 mm Hg
Delayed or absent femoral pulses
Murmur
Coarctation of the aortaMagnetic resonance imaging (adults)
Transthoracic echocardiography (children)
Increase in serum creatinine concentration (≥ 0.5 to 1 mg per dL [44.20 to 88.40 μmol per L]) after starting angiotensin-converting enzyme inhibitor or angiotensin receptor blocker
Renal bruit
Renal artery stenosisComputed tomography angiography
Doppler ultrasonography of renal arteries
Magnetic resonance imaging with gadolinium contrast media
Bradycardia/tachycardia
Cold/heat intolerance
Constipation/diarrhea
Irregular, heavy, or absent menstrual cycle
Thyroid disordersThyroid-stimulating hormone
HypokalemiaAldosteronismRenin and aldosterone levels to calculate aldosterone/renin ratio
Apneic events during sleep
Daytime sleepiness
Snoring
Obstructive sleep apneaPolysomnography (sleep study)
Sleep Apnea Clinical Score with nighttime pulse oximetry
Flushing
Headaches
Labile blood pressures
Orthostatic hypotension
Palpitations
Sweating
Syncope
Pheochromocytoma24-hour urinary fractionated metanephrines
Plasma free metanephrines
Buffalo hump
Central obesity
Moon facies
Striae
Cushing syndrome24-hour urinary cortisol
Late-night salivary cortisol
Low-dose dexamethasone suppression