Aldosterone synthase inhibitors may alter how primary care treats hypertension

Hypertension guidelines recommend adding antihypertensive therapies until the blood pressure (BP) is below a specific target. If the BP is not below target with 3 medications, including a diuretic, then it is labeled resistant hypertension, and then we investigate for secondary causes, such as primary aldosteronism (PA). PA testing seems complex with 3 results: aldosterone, renin, and the aldosterone-renin ratio. Hence, these tests are ordered infrequently, and the diagnosis of PA is often delayed or never made. Also, heart failure, chronic kidney disease, and other conditions can have elevated aldosterone, which are not PA-related. The traditional treatment with aldosterone receptor blockers/mineralocorticoid receptor antagonists has been helpful, but they block the effects that are mediated through the mineralocorticoid receptor. The non-receptor effects of high aldosterone may continue to cause harm. Therefore, blocking the production of aldosterone with an aldosterone synthase inhibitor (ASI) could be a more complete strategy to address elevated aldosterone levels. In addition, an “ASI Challenge” may help us decide which patients need formal testing for PA. If the systolic blood pressure drops a significant amount (>10 mm Hg), then that suggests aldosterone is a key component of the uncontrolled BP, and those patients should be considered for formal PA testing. For those who drop a modest amount (<10 mm Hg), they would be less likely to need PA testing. Such an approach could use an ASI agent as a diagnostic/screening tool as well as a therapeutic agent, which would be very helpful in the primary care setting.