Diabetics with
high blood pressure benefit from“Water Pills”
Newswise — Diuretics (water pills) work better than newer and more
costly medicines in the treatment of high blood pressure and
prevention of some forms of heart disease in people with type 2
diabetes, according to results from the Antihypertensive and
Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT).
ALLHAT, the largest hypertension clinical trial ever conducted, was
led in part by Tulane University physician and epidemiologist Paul
K. Whelton, senior vice president for health sciences and lead
author for the current report published in the June 27th issue of
the Archives of Internal Medicine.
“Almost three out of every four persons with type 2 diabetes has
hypertension, putting them at substantial risk for cardiovascular
disease,” Whelton says.
An important question in patients with type 2 diabetes and
hypertension has been whether it makes a difference which medicine
is used for initial therapy of high blood pressure.
“ALLHAT
is the largest study to address this question, comparing four
different classes of antihypertensive medication: diuretics,
angiotensin-converting enzyme [ACE] inhibitors, calcium channel
blockers and alpha receptor blockers,” Whelton says.
In an
earlier publication (Journal of the American Medical Association,
December 2002), the ALLHAT investigators reported that diuretics
were superior in preventing adverse cardiovascular disease outcomes
compared with other first-step antihypertensive medications. The
current report indicates that this is true not only in hypertensive
patients with a normal blood sugar, but in those with diabetes, or
an impaired fasting glucose (pre-diabetes).
The
Archives publication was based on long-term clinical trial
experience in 31,512 men and women who were all 55 years old or
older with stage 1 or stage 2 hypertension and at least one
additional risk factor for coronary heart disease. Study
participants were assigned to initial treatment with either a
calcium channel blocker (amlodipine), an ACE inhibitor (lisinopril)
or a diuretic (chlorthalidone).
Compared with the ACE inhibitor and the calcium channel blocker, the
diuretic was:
* More
protective against heart failure in patients with or without
diabetes (by about 1/6th compared with the ACE inhibitor, and by
about 1/3rd compared with the calcium channel blocker).
* More
protective against stroke in people with or without diabetes
(compared with the ACE inhibitor). This benefit was seen only in
Black patients.
*
Slightly more effective in lowering systolic blood pressure-the
measure of blood pressure when the heart beats-among those with or
without diabetes.
* At
least equally protective against fatal coronary heart disease or
non-fatal heart attacks in diabetics, those with an impaired fasting
glucose, and in those with a normal blood sugar.
*
Equally protective against death, end-stage renal disease or cancer
in diabetics, those with an impaired fasting glucose, and in those
with a normal blood sugar.
“Independent of diabetes status, our results suggest that diuretics
are better than ACE inhibitors and calcium channel blockers in
preventing certain cardiovascular disease complications-especially
heart failure-during initial treatment of high blood pressure.
Patients with diabetes and high blood pressure should not change
their antihypertensive medications without discussing this option
with their doctors,” says Whelton.
The
study was sponsored by the National Heart, Lung and Blood Institute.
At Tulane, Whelton's co-authors include Gail T. Louis, R.N. The
study was conducted at 623 clinics and centers across the United
States and in Canada, Puerto Rico and the U.S. Virgin Islands.
