Resistant
hypertension is a major opportunity for prevention of
cardiovascular disease. Despite widespread dissemination of consensus guidelines, most patients are uncontrolled with approaches that assume that all patients are the same. Causes of resistant
hypertension include 1) non-compliance 2) consumption of substances that aggravate
hypertension (such as
salt, alcohol, nonsteroidal anti-inflammatory drugs, licorice,
decongestants) and 3) secondary
hypertension. Selecting the appropriate
therapy for a patient depends on finding the cause of the
hypertension. Once rare causes have been eliminated (such as
pheochromocytoma, licorice, adult
coarctation of the aorta), the cause will usually be found by intelligent interpretation (in the light of medications then being taken) of plasma
renin and
aldosterone.If stimulated
renin is low and the
aldosterone is high, the problem is primary
aldosteronism, and the best treatment is usually
aldosterone antagonists (
spironolactone or
eplerenone; high-dose
amiloride for men where
eplerenone is not available). If the
renin is high, with secondary
hyperaldosteronism, the best treatment is
angiotensin receptor blockers or
aliskiren. If the
renin and
aldosterone are both low the problem is over-activity of renal
sodium channels and the treatment is
amiloride. This approach is particularly important in patients of African origin, who are more likely to have low-
renin hypertension.