Primary Aldosteronism

Resistant hypertension can reflect an adrenal hormone disorder rather than simply a need for another antihypertensive. In primary aldosteronism, aldosterone secretion escapes renin control: sodium retention expands extracellular volume, renin remains suppressed, and blood pressure rises. Potassium may be normal, so the absence of hypokalemia does not exclude the diagnosis. For Canadian primary care, the main entry points are resistant hypertension, spontaneous or diuretic-induced hypokalemia, and an adrenal incidentaloma. Hypertension Canada recommends screening and referral in these high-probability presentations. The 2025 Endocrine Society guideline takes a broader position and suggests screening every person with hypertension, an approach particularly relevant to endocrine practice. The clinical sequence is biochemical screening first, followed by a decision about whether surgery is being pursued before lateralization studies are ordered.