What are the signs of hyperaldosteronism?

Signs of Hyperaldosteronism

The primary signs of hyperaldosteronism include hypertension, hypokalemia, and suppressed plasma renin activity, though hypokalemia is often a late manifestation and may be absent in many cases. 1

Clinical Presentation

• Hypertension: The most common and often the earliest sign, particularly resistant hypertension (BP not controlled on 3 medications including a diuretic) 1
• Hypokalemia: Low potassium levels due to increased potassium excretion, though this is present in only a minority of cases and is considered a late manifestation 1, 2
• Muscle weakness or cramps: Related to potassium depletion 1
• Metabolic alkalosis: Due to increased hydrogen ion excretion 2
• Suppressed plasma renin activity: A hallmark laboratory finding 1, 3
• Elevated aldosterone levels: Despite sodium retention 1, 2

Risk Factors and Prevalence

• Primary aldosteronism is present in approximately 6% of all hypertensive patients 4
• The prevalence increases to 13-20% among patients with resistant hypertension 1
• The condition is equally prevalent in African-American and white patients 1

Diagnostic Indicators

• Aldosterone-to-renin ratio (ARR): The recommended screening test, with a ratio >30 considered positive when plasma aldosterone concentration is reported in ng/dL and plasma renin activity in ng/mL/h 1, 2
• Plasma aldosterone concentration: Should be at least 10 ng/dL to interpret the ARR test as positive 2, 3
• Normal potassium levels: Do not exclude hyperaldosteronism, as many patients have normokalemic hyperaldosteronism 5, 6

Complications and Associated Conditions

• Cardiovascular damage: Increased risk of left ventricular hypertrophy (69% vs 25.7% in essential hypertension) 7
• Higher cardiovascular morbidity and mortality: Due to aldosterone's direct damaging effects on the cardiovascular system 7
• Hypertensive emergencies: May be the presenting feature in some cases 8
• Metabolic abnormalities: Including glucose intolerance 2

When to Suspect Primary Aldosteronism

Primary aldosteronism should be suspected in patients with:

• Resistant hypertension (BP not controlled on 3 medications including a diuretic) 1, 2
• Hypertension with spontaneous or diuretic-induced hypokalemia 1
• Severe hypertension (BP >180/110 mmHg) 1
• Hypertension with an incidentally discovered adrenal mass 1
• Family history of early-onset hypertension 1, 2
• Hypertension and stroke at a young age (<40 years) 1, 2
• First-degree relative with confirmed primary aldosteronism 4

Common Pitfalls in Diagnosis

• Relying on hypokalemia: Only screening patients with hypokalemia will miss most cases of primary aldosteronism 1, 6
• Not screening high-risk patients: Only about 2-4% of eligible patients are screened for primary aldosteronism 3
• Medication interference: Beta-blockers, centrally acting drugs, and diuretics can interfere with test results 3
• Inadequate patient preparation: Patients should be potassium-replete before testing 3

By recognizing these signs and risk factors, clinicians can identify patients who should undergo screening for primary aldosteronism, leading to earlier diagnosis and more effective treatment to reduce cardiovascular morbidity and mortality.