BIRMINGHAM, Ala. -- Resistant hypertension, blood pressure that
remains above goal despite taking three antihypertensive medications or
high blood pressure that is controlled but requires four or more
medications to do so, may benefit from specialized diagnostic and
therapeutic treatment by health care providers according to guidelines
issued by the American Heart Association and co-authored by UAB
Lead author David A. Calhoun, M.D., professor of medicine in the UAB
Division of Cardiovascular Disease, and colleagues said successfully
treating resistant hypertension requires patients to modify lifestyle
factors that contribute to treatment resistance, including using less
salt, losing weight and drinking less alcohol. It also requires
physicians to better diagnose and treat secondary causes of high blood
pressure and more effectively use multiple-drug treatments. This is the
first consensus statement to define resistant hypertension and
recommend an approach for evaluation and treatment.
Calhoun said while it is not known how many people in the U.S. with
high blood pressure have resistant hypertension clinical trials suggest
it may as high as 20 to 30 percent.
"Older age and obesity are two of the strongest risk factors
associated with resistant hypertension and unfortunately, with an aging
and increasing heavy population, we can anticipate resistant
hypertension becoming more and more common," he said. "And people need
to recognize the importance of blood pressure control. Persons with
resistant hypertension are at increased risk for cardiovascular
diseases, including heart attacks and strokes."
Calhoun and colleagues emphasize in the statement that effective use
of diuretics is essential for treatment of resistant hypertension.
Calhoun said they recommend that a long-acting diuretic be part of the
treatment regimen of all patients with resistant hypertension in order
reduce fluid retention and thereby blood pressure. He added that some
patients may also benefit from adding mineralocorticoid receptor
antagonists (MRAs) to their treatment regimens. MRAs have traditionally
been used to treat a condition called primary aldosteronism, which is
found in about 20 percent of patients with resistant hypertension.
However, recent clinical studies indicate that MRAs may be useful in
treating resistant hypertension even in the absence of demonstrable
"The benefit of MRAs for treating resistant hypertension has been
recently appreciated," he said. "Hypertension specialists are using
them more commonly, but they are probably not being routinely used by
other physicians. Prescription of MRAs does require biochemical
monitoring, particularly measurement of serum potassium levels, which
does limit there use."
Calhoun said it is important to note that uncontrolled high blood
pressure and resistant hypertension are not the same and effectively
evaluating a patient to distinguish between the two possibilities is
key to successful treatment.
"High blood pressure readings can be caused by poor medication
adherence, which is not the same as resistant hypertension," he said.
"Confirming treatment resistance is the first step in evaluating
difficult-to-treat high blood pressure. It also is important to
evaluate the condition correctly because often, patients with resistant
hypertension have other medical conditions that complicate their blood
pressure management. If a secondary cause of hypertension is identified
such as obstructive sleep apnea, renal parenchymal disease, primary
aldosteronism or renal artery stenosis, treating these disorders, which
may require referral to a specialist, can improve blood pressure