From the Guidelines
Primary hyperaldosteronism is a relatively common condition, affecting approximately 5-10% of all patients with hypertension, as reported in the most recent and highest quality study 1. This condition is characterized by excessive aldosterone production from the adrenal glands and is the most common cause of secondary hypertension. The prevalence of primary hyperaldosteronism increases with the severity of hypertension and is often underdiagnosed in clinical practice. Some key points to consider include:
- The condition is more prevalent in certain subgroups, with rates of 15-20% among patients with resistant hypertension (hypertension requiring three or more medications for control) 1.
- Screening is typically recommended for patients with hypertension plus hypokalemia, resistant hypertension, early-onset hypertension (before age 40), or hypertension with adrenal incidentaloma 1.
- The two main subtypes are aldosterone-producing adenoma (30-40% of cases) and bilateral adrenal hyperplasia (60-70% of cases) 1.
- Early diagnosis is important because primary hyperaldosteronism not only causes hypertension but also leads to cardiovascular and renal damage independent of blood pressure levels due to the direct harmful effects of excess aldosterone on these organ systems 1. It is essential to note that the management of primary aldosteronism depends on its subtype, and surgical removal of the offending adrenal gland is typically considered for unilateral primary aldosteronism, while medical treatment with mineralocorticoid receptor antagonists (MRAs) is the primary approach for bilateral primary aldosteronism 1.
From the Research
Prevalence of Primary Hyperaldosteronism
- Primary hyperaldosteronism is estimated to be the underlying cause of hypertension in approximately 6% of cases in primary care settings 2.
- It is even more common in patients with resistant hypertension, with a prevalence ranging from 3 to 9% 3.
- The disorder is estimated to be present in 5-10% of hypertension cases, with a cardiovascular risk profile double that of essential hypertensives 4.
Detection and Diagnosis
- The aldosterone-to-renin ratio is an easy, inexpensive, and rapid means of screening for primary hyperaldosteronism, with a ratio greater than 30 indicating independent aldosterone secretion 2.
- Confirmatory tests, such as the captopril challenge, oral or intravenous salt loading, or fludrocortisone suppression, are necessary to clinch the diagnosis 2, 3.
- Adrenal computed tomography and adrenal vein sampling are used to differentiate between unilateral and bilateral adrenal production of aldosterone 2, 4.
Classification and Treatment
- Primary hyperaldosteronism can be classified into two main subtypes: unilateral (aldosterone-producing adenoma) and bilateral (micro- or macronodular hyperplasia) 5, 3.
- Treatment options include unilateral adrenalectomy for aldosterone-producing adenomas and mineralocorticoid receptor antagonists, such as spironolactone or eplerenone, for bilateral hyperaldosteronism 5, 2, 4.