Nearly half of American adults live with high blood pressure, and most are treated with the same first-line drugs. But for a large minority, the driver is not lifestyle or age. It is a hormonal condition called primary aldosteronism, and it is potentially curable when found.
The problem is that hardly anyone gets tested. Researchers reviewing screening in recent years report that only 1 to 2 percent of eligible patients are checked, even among those at highest risk. In a US analysis of more than 200,000 veterans with treatment-resistant hypertension, fewer than 2 percent were screened.
What primary aldosteronism actually is
Primary aldosteronism happens when the adrenal glands, two small hormone factories that sit on top of the kidneys, produce too much aldosterone. That hormone tells the body to hold on to salt and water and to shed potassium, which pushes blood pressure up.
It usually comes from one of two things. Either a small benign tumor on one adrenal gland is doing the overproducing, in which case surgery can cure the condition. Or both glands are producing too much, and daily medication is used to block the hormone's effect.
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Why it matters more than ordinary hypertension
People with primary aldosteronism carry a substantially heavier cardiovascular load than people with regular high blood pressure. The Endocrine Society's 2025 clinical practice guideline reports a 2.58 times higher risk of stroke, a 3.52 times higher risk of atrial fibrillation, and roughly a doubling in the risk of heart failure and coronary artery disease compared with primary hypertension. Kidney disease risk is also elevated.
"People with primary aldosteronism face a higher risk of cardiovascular disease than those with primary hypertension," said Gail K. Adler, chair of the guideline writing group, in the Endocrine Society's announcement.
The condition is not rare. The same guideline estimates that 5 to 14 percent of people with high blood pressure in primary care have it, and up to 30 percent of those seen in referral centers. Prevalence climbs in specific groups: about 16 percent in adults with young-onset hypertension, 11 to 29 percent in resistant cases, and around 28 percent when hypertension is accompanied by low potassium.
Why doctors keep missing it
A qualitative study published in Kidney Medicine in 2026 by researchers at Australia's Hudson Institute of Medical Research and Monash University interviewed 38 general practitioners, nephrologists, endocrinologists and cardiologists from every state and territory in Australia. It found a pattern of concrete barriers rather than a single failure.
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"Key barriers included perceptions about PA patient profiles, where older and co-morbid populations are often not considered candidates for screening," said first author Sandra Hakim, according to a Hudson Institute release. Clinicians also cited the perceived complexity of diagnostic testing, limited access to specialists, and fragmented care that delays follow-up.
The consequence is that many patients keep taking blood pressure pills for years without anyone checking whether a fixable hormonal cause is behind the readings. "Patients can only benefit if they are diagnosed in the first place," said Professor Jun Yang of Hudson Institute in the same release.
What patients can ask
The Endocrine Society's 2025 guideline now recommends screening all adults with hypertension using a simple blood test that measures aldosterone, renin, and potassium. The test is low-cost and does not require stopping most medications up front.
Given that hypertension affects about 119.9 million US adults, or 48.1 percent of the adult population, according to CDC data, even a conservative prevalence of 5 to 10 percent would mean millions of Americans with an unrecognized, treatable cause of their blood pressure.
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Anyone whose blood pressure remains high despite treatment, who developed hypertension young, or whose potassium tends to run low can ask their doctor whether screening for primary aldosteronism is appropriate.
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