Hypertension affects roughly one in three adults globally, yet a significant hormonal driver hiding beneath the surface goes undetected in the vast majority of cases. Primary aldosteronism — where one or both adrenal glands produce excess aldosterone independent of normal physiological cues — is now recognized as the most common correctable cause of secondary hypertension, and its cardiovascular and renal consequences extend well beyond what elevated blood pressure alone would predict.
This comprehensive primer details how PA arises from a spectrum of somatic and germline mutations in aldosterone-driver genes, compounded by aberrant expression of G-protein-coupled receptors in adrenal tissue that further dysregulate aldosterone synthesis. The excess mineralocorticoid activity suppresses renin, promotes sodium retention, and drives end-organ damage through mechanisms partly independent of blood pressure — including direct fibrotic and inflammatory effects on cardiac and renal tissue. A clinically important subgroup also exhibits cortisol co-secretion, compounding cardiometabolic risk beyond what aldosterone excess alone produces. Diagnosis hinges on measuring the aldosterone-to-renin ratio in all hypertensive patients, a step still widely omitted in routine practice. Lateralization workup — distinguishing unilateral from bilateral disease — determines whether surgical adrenalectomy or long-term medical management with mineralocorticoid receptor antagonists (MRAs) is appropriate. Aldosterone synthase inhibitors represent an emerging pharmacological frontier for bilateral disease.
The broader significance here is epidemiological and clinical. Prevalence estimates for PA among hypertensive patients have risen substantially with improved screening — from historical figures near 1% to contemporary estimates exceeding 5–10% in referred populations, and potentially higher in treatment-resistant hypertension. The persistent underdiagnosis means millions are receiving antihypertensive therapy that suppresses blood pressure but does not neutralize the direct organ-damaging effects of aldosterone. The primer's emphasis on renin normalization as a therapeutic biomarker rather than blood pressure alone represents a meaningful conceptual shift in monitoring adequacy of treatment. Limitations of the current evidence base include reliance on referral-center cohorts, variability in adrenal vein sampling technique across institutions, and the early-stage status of aldosterone synthase inhibitor trials. For health-conscious adults, the takeaway is structural: routine aldosterone-renin testing in hypertension deserves far wider adoption than current practice reflects.