Spironolactone Versus Amiloride as an Add on Agent in Resistant Hypertension
Status:
Withdrawn
Trial end date:
2010-11-01
Target enrollment:
Participant gender:
Summary
Joint National Committee 7 (JNC-7) defines resistant hypertension as a persistent elevation
of blood pressure (BP) above goal - ≥ 140/90 mm Hg for the general hypertensive population or
≥ 130/80 mm Hg for persons with diabetes mellitus or chronic kidney disease - for at least
three months despite treatment with three or more optimally dosed antihypertensive agents,
including a diuretic. The exact prevalence of resistant hypertension is uncertain but may
include 5-20% of hypertensive persons in primary care settings and 15-35% of the older,
higher cardiovascular risk hypertensive patients incorporated into recent clinical trials of
antihypertensive therapy. Observational studies demonstrate that patients with resistant
hypertension experience a higher rate of cardiovascular and renal target organ damage such as
left ventricular hypertrophy, microalbuminuria, and renal insufficiency and more
cardiovascular disease (CVD) events than patients whose hypertension is well-controlled.
Additionally, resistant hypertension patients may be subjected to the considerable expense of
multiple office visits, diagnostic testing for secondary causes of hypertension, and referral
to hypertension specialists. Because multiple factors can contribute to resistant
hypertension, an explicit, sequential approach to evaluation and management is essential to
optimize blood pressure, reduce cardiorenal morbidity and mortality, and avoid unnecessary
expense. A number of observational studies have suggested the potential efficacy of both
spironolactone and amiloride when added to a 3 drug antihypertensive regimen, but to date no
randomized study has directly compared the two agents. The goal of this study is to determine
whether spironolactone or amiloride is the more effective fourth agent to add to a three drug
regimen in patients with resistant hypertension.