Primary Aldosteronism Causes Hypertension, Not Hypotension
Primary aldosteronism (PA) causes hypertension, not hypotension—this is a defining feature of the disease. The excessive aldosterone production leads to sodium retention and volume expansion, which drives blood pressure elevation 1, 2.
The Core Pathophysiology
PA results from autonomous aldosterone overproduction by one or both adrenal glands, independent of the renin-angiotensin system. This causes:
- Sodium retention
- Potassium wasting (hypokalemia)
- Volume expansion
- Moderate to severe hypertension 3
The 2025 Endocrine Society guideline explicitly identifies PA as "a common cause of hypertension" and notes it affects up to 14% of patients with hypertension in primary care and up to 30% with resistant hypertension 1, 4.
Important Clinical Caveat: Normotensive PA Exists
While hypertension is the predominant manifestation, PA can rarely present without hypertension, making diagnosis challenging 5. A 2026 case report documented normotensive PA presenting with life-threatening ventricular arrhythmias from severe hypokalemia, demonstrating that blood pressure elevation is not universal 5. This underscores the importance of screening for PA in patients with unexplained treatment-resistant hypokalemia and arrhythmias regardless of blood pressure status.
The Exceptional Case: Concurrent Dysautonomia
The only documented scenario where hypotension occurs with PA involves the extremely rare coexistence of PA with chronic idiopathic orthostatic hypotension (dysautonomia) 6. In this 1991 case report, a patient had incapacitating postural hypotension alongside supine hypertension from an aldosterone-secreting adenoma. This represents two separate, unrelated pathologic processes occurring simultaneously—not PA causing hypotension.
Clinical Bottom Line
- Screen all hypertensive patients for PA using aldosterone and renin measurements with aldosterone-to-renin ratio (ARR) 1
- If you encounter hypotension in a patient, PA is not the cause—look elsewhere
- The cardiovascular complications from PA (stroke, coronary disease, atrial fibrillation, heart failure) result from both the hypertension and direct aldosterone-mediated effects on the heart and vasculature 2
- Hypokalemia, not hypotension, is the electrolyte hallmark that may prompt PA screening 3, 7