Secondary Hypertension

When to Suspect Secondary Hypertension:
1.  Severe, resistant hypertension (not well controlled despite 3 or more BP agents)
2.  Acute rise in BP over previously stable BP
3.   Young age of onset (<30 yo), esp if in non-obese, non-black patients without other clear risk factors; also, onset in older pts (>55 yo) in pts who have severe atherosclerosis (--> suspect renal artery stenosis)
4.  Presenting with hypertensive emergency

Causes of Secondary HTN (not an exhaustive list):

1. Renal parenchymal disease (Chronic Kidney Disease) - obviously this is very common.  Pathophysiology revolves around chronic Na retention.
2. Renovascular disease - Renal Artery Stenosis (older pts with diffuse atherosclerosis), less commonly Fibromuscular Dysplasia (females > males)
3. Endocrine causes - Pheochromocytoma, Hyperaldosteronism (see below), Cushing's Syndrome, Hyperparathyroidism (leading to Hypercalcemia --> increased SVR)
4. Aortic Coarctation
5. Drugs - cocaine/methamphetamines, chronic NSAIDs, OCPs
6. Obstructive Sleep Apnea

(Chanu Rhee MD, 10/22/10)