From the Guidelines
Primary aldosteronism is the most common secondary cause of resistant hypertension. This condition occurs when the adrenal glands produce excessive amounts of aldosterone, a hormone that increases sodium reabsorption and potassium excretion in the kidneys, leading to fluid accumulation and elevated blood pressure that often remains high despite treatment with multiple antihypertensive medications 1. According to the 2024 ESC guidelines for the management of elevated blood pressure and hypertension, primary aldosteronism is the most common form of secondary hypertension 1.
Key Points
- Primary aldosteronism is estimated to be present in 10-20% of patients with resistant hypertension 1.
- Diagnosis typically involves screening with plasma aldosterone concentration to plasma renin activity ratio, followed by confirmatory testing such as salt loading tests or captopril challenge.
- Treatment options include mineralocorticoid receptor antagonists like spironolactone (starting at 25-50 mg daily) or eplerenone (50-100 mg daily), which directly block aldosterone's effects 1.
- In cases of unilateral adrenal adenoma, surgical adrenalectomy may be curative.
- Patients with suspected primary aldosteronism should undergo evaluation for hypokalemia and metabolic alkalosis, which are common but not universal findings.
Management
The management of primary aldosteronism depends on its subtype, particularly on adrenal lesions being unilateral or bilateral 1. For unilateral primary aldosteronism, surgical removal of the offending adrenal gland is typically considered, unless the patient is older or has co-morbidities of concern 1. Medical treatment is currently based on MRAs, with spironolactone being the most widely available 1. The effective dose of spironolactone can be titrated up to 300–400 mg once daily, if necessary 1.
Screening and Diagnosis
The aldosterone:renin activity ratio is currently the most accurate and reliable means of screening for primary aldosteronism 1. Patients with hypertension and a history of early onset hypertension and/or cerebrovascular accident at a young age may have primary aldosteronism due to glucocorticoid-remediable aldosteronism (familial hyperaldosteronism type-1) and therefore warrant screening 1. Early identification and treatment of primary aldosteronism in resistant hypertension cases can lead to significant improvements in blood pressure control and reduction in cardiovascular risk 1.
From the Research
Most Common Secondary Cause of Resistant Hypertension
- The most common secondary cause of resistant hypertension is a topic of ongoing research and debate 2, 3.
- According to a study published in 2022, primary aldosteronism is recognized as the most common cause of secondary hypertension, with a prevalence of up to 29.1% in patients with resistant hypertension 4.
- However, another study published in 2011 found that obstructive sleep apnea was the most common condition associated with resistant hypertension, affecting 64.0% of patients 3.
- Primary aldosteronism is also a common cause of resistant hypertension, with a prevalence of 5.6% in one study 3 and estimated to be the underlying cause of hypertension in approximately 6% of cases in primary care settings 5.
- The identification of primary aldosteronism as a common cause of resistant hypertension is a significant advance in the ability to care for patients with hypertension 6.
- The pathophysiological mechanisms of primary aldosteronism and its relationship to resistant hypertension are complex and involve multiple factors, including aldosterone-induced vascular remodeling, sympathetic overactivity, insulin resistance, and adipose tissue dysfunction 4.