From the Guidelines
The workup for hyperaldosteronism begins with screening tests in patients with suspected primary aldosteronism, including those with resistant hypertension, hypokalemia, adrenal incidentaloma, or family history of early-onset hypertension, and should follow the guidelines outlined in the most recent and highest quality study, which recommends measuring the aldosterone-to-renin ratio (ARR) while the patient is on an unrestricted salt diet 1.
Initial Screening
Initial screening involves measuring the aldosterone-to-renin ratio (ARR) while the patient is on an unrestricted salt diet.
- An ARR greater than 30 ng/dL per ng/mL/hr (or >20 with aldosterone >15 ng/dL) suggests primary aldosteronism.
- Before testing, interfering medications should be discontinued: spironolactone and eplerenone for 4-6 weeks; ACE inhibitors, ARBs, and diuretics for 2 weeks; and beta-blockers for 1 week.
Confirmation Testing
Confirmation testing follows positive screening and may include:
- Oral salt loading
- Saline infusion
- Fludrocortisone suppression
- Captopril challenge tests
Subtype Differentiation
Once primary aldosteronism is confirmed, subtype differentiation is necessary through:
- Adrenal CT imaging
- Adrenal vein sampling to distinguish between unilateral (typically aldosterone-producing adenoma) and bilateral disease (idiopathic hyperaldosteronism).
Treatment
This distinction is crucial as unilateral disease may be cured surgically with adrenalectomy, while bilateral disease requires medical management with mineralocorticoid receptor antagonists like:
- Spironolactone (starting at 12.5-25 mg daily, titrating up to 100-400 mg daily)
- Eplerenone (starting at 25 mg twice daily, up to 100 mg twice daily) 1.
The most recent guidelines recommend the use of newer agents, such as the non-steroidal MRAs finerenone and exarenone, and the aldosterone synthase inhibitor baxdrostat, which lower BP in resistant hypertension, and are also being tested for treating primary aldosteronism 1.
From the FDA Drug Label
2.5 Treatment of Primary Hyperaldosteronism Administer spironolactone tablets in doses of 100 mg to 400 mg daily in preparation for surgery. For patients who are considered unsuitable for surgery, spironolactone tablets can be used as long-term maintenance therapy at the lowest effective dosage determined for the individual patient.
Hyperaldosteronism Workup: The FDA drug label does not provide a specific workup for hyperaldosteronism. However, it does mention the use of spironolactone in the treatment of primary hyperaldosteronism, indicating that it can be used in preparation for surgery or as long-term maintenance therapy in patients who are not candidates for surgery 2.
- Key Points: + Spironolactone can be used to treat primary hyperaldosteronism. + The dosage for primary hyperaldosteronism is 100 mg to 400 mg daily. + It can be used in preparation for surgery or as long-term maintenance therapy. However, the actual workup and diagnosis of hyperaldosteronism are not addressed in the provided drug labels.
From the Research
Hyperaldosteronism Workup
- Hyperaldosteronism is a common secondary cause of hypertension, accounting for 10% of hypertensives and 20% of those with drug-resistant hypertension 3
- The aldosterone-to-renin ratio (ARR) is the most practical and informative initial test for screening primary aldosteronism (PA) 3, 4, 5, 6, 7
- Confirmatory tests for PA include: + Oral salt loading + Saline infusion + Captopril challenge + Fludrocortisone suppression test 3 + Urinary aldosterone excretion on a high-salt diet + Aldosterone suppression after a saline infusion 4
- Adrenal imaging and adrenal venous sampling (AVS) are essential for determining the subtype of PA and selecting the appropriate treatment modality 5, 6, 7
- Treatment for PA depends on the subtype, with unilateral adrenalectomy for aldosterone-producing adenoma and pharmacological approaches using mineralocorticoid antagonists for bilateral adrenal hyperplasia 4, 5, 7
- Mineralocorticoid receptor antagonists, such as spironolactone, are the drug of choice for treating PA, with the goal of preventing long-term sequelae of hypertension 4, 5, 7