The National Institutes of Health (NIH) called an early
to one arm of a study on the advice of an independent data
safety monitoring board after finding that people with kidney
disease and protein in their urine were more likely to
kidney failure using either an angiotensin-converting enzyme
inhibitor or a beta blocker than a calcium channel blocker
The ACE inhibitor ramipril (Altace®) or the beta blocker
(Toprol®) significantly reduced the risk of kidney
compared to the CCB amlodipine (Norvasc®) in a group of
who had at least one gram of protein in a 24-hour sample of
when they joined the African American Study of Kidney Disease
and Hypertension (AASK). Blood pressures were comparable.
Paradoxically, CCBs are one of two first-choice medicines
high blood pressure in African Americans1;
62 percent of AASK patients were on CCBs before joining the
The type of CCB used in AASK, a dihydropyridine, was found in
this study and in other recent studies to increase protein in
the urine. Protein increases are linked with advancing kidney
ACE inhibitors have been preferred for kidney disease of
since 1994. Subsequent studies of other kidney diseases have
an association between protein in the urine and protection by
ACE inhibition. Considered with the results of these other
AASK extends the value of ACE inhibitors to kidney disease of
hypertension, at least for people with protein in the urine.
"This trial will have a tremendous effect on how we care for
people," predicts Dr. Janice Douglas, chair of the study's
committee and director of the hypertension division at
Hospitals of Cleveland and at Case Western Reserve University
School of Medicine. "Most striking to me is the correlation
elevated urine protein and faster disease progression,
we can look for in all people with kidney disease," she
Dr. Douglas will present the study at the 33rd annual meeting
of the American Society of Nephrology (ASN) in Toronto.
Dr. Lawrence Agodoa, a kidney specialist and NIH director of
AASK, cautions patients to keep taking prescribed blood
medicine until they have worked out an alternative with their
doctor. "Calcium channel blockers are good for controlling
blood pressure, and patients are not in immediate risk," he
AASK will continue to compare the ACE inhibitor and beta
and to test whether a lower blood pressure target of 125/75
more protective of the kidneys than 140/90. The CCB may be
as a secondary treatment if needed to reach blood pressure
AASK enrolled 1,094 African Americans at 21 centers and is
to end in the fall of 2001.
African Americans make up 12.6 percent of the U.S.
but 29.8 percent of people treated for kidney failure.
hit are blacks ages 25 to 44, who are 20 times more
to hypertension-related kidney failure. Better management of
blood pressure has led to fewer strokes and heart disease,
kidney failure is still increasing.
1 The 6th Report of the Joint
National Committee on Prevention, Detection, Evaluation, and
of High Blood Pressure, November 1997.
Notes to Editors:
The phone number for the ASN Press Room in Toronto is
AASK is funded in part by the NIH Office of Research on
Study drugs are provided by Pfizer, Monarch/King
and Astra USA.