Who and How Should We Screen for Primary Aldosteronism?

Abstract

There are mounting data that at least 30% of hypertensives who are appropriately screened have primary aldosteronism (PA), rather than the commonly reported figure of 5% to 10%. Second, there are similar data that undertreated patients with PA have a 3-fold higher risk profile than essential hypertensives with the same blood pressure levels. Third, clinicians managing hypertension measure success as sustainable lowering of blood pressure; untreated hypertensive patients with PA are thus in double jeopardy. Finally, and crucially, fewer than 1% of patients with hypertension are ever screened—let alone investigated—for PA. Accordingly, for “Who should we screen?” the answer is simple—all patients with hypertension. For “How they should be screened?” the answer is also simple—add spironolactone 25 mg/day for 4 weeks and measure the blood pressure response. In established hypertension, a fall of <10 mm Hg means PA is unlikely; above 12 mm Hg PA, it is probable. Newly presenting hypertension is much the same—hold off on first-order antihypertensive(s) and prescribe spironolactone 25 mg/day for 4 weeks. If blood pressure falls into the normal range, continue; if it does not, prescribe a standard antihypertensive. It is likely that the above protocols—a first start, amenable to refinement—will find additional hypertensives with unilateral PA; it is probable that the overwhelming majority will have bilateral disease. What this means is that we have a major public health issue on our hands: how can this be the case?