Making Multiple Lifestyle Changes is
Beneficial, Achievable in Lowering High Blood Pressure
Men and women with elevated blood pressure who make healthy lifestyle
changes and sustain them for up to a year and a half can substantially
reduce their rates of high blood pressure and potentially decrease
their heart disease risk. With behavioral counseling, increases
in physical activity, and adoption of a healthy eating plan called
DASH, rates of high blood pressure dropped from 37 to 22 percent
among participants in a study conducted by the National Heart, Lung,
and Blood Institute (NHLBI) of the National Institutes of Health.
High blood pressure is a major risk factor for heart disease and
the chief risk factor for stroke. About 65 million American adults,
one in three, have high blood pressure. An additional 59 million
adults have prehypertension, a level that is above normal, and increases
risk of heart disease and stroke. Results of the study, called PREMIER,
appear in the April 4, 2006 issue of Annals of Internal Medicine.
“This study underscores the value of lifestyle changes—namely
improving diet and increasing physical activity—in reducing
high blood pressure, an important public health problem,”
said NHLBI Director Elizabeth G. Nabel, M.D. “For the millions
of Americans with prehypertension and hypertension, this shows that
individuals can make healthy lifestyle changes to keep blood pressure
under control without the use of medications.”
A total of 810 men and women ages 25 and older with either prehypertension
(120-139mmHg/80-89mmHg) or stage 1 hypertension (140-159mmHg/90-95mmHg)
but who were not taking medications to control blood pressure were
randomly assigned to three groups. Participants in two of the groups
attended 18 counseling sessions during the first six months—14
group meetings and 4 individual sessions. During the last 12 months
they attended 12 group meetings and 3 individual sessions. They
were prescribed goals for weight loss, physical activity, and given
sodium and alcohol intake limits. One of these groups also received
guidance on implementing the Dietary Approaches to Stop Hypertension
diet (DASH), an eating plan rich in fruits and vegetables, low-fat
dairy products and low in saturated, total fat and dietary cholesterol.
DASH is used as an example of a healthy eating plan by the U.S.
Dietary Guidelines for Americans, and has been shown to lower blood
pressure in previous NHLBI studies.
A third group served as a control, receiving only two 30-minute
sessions of advice to follow standard recommendations for blood
pressure control; one at study enrollment and one 6 months later.
A third session was offered at the end of the 18-month trial after
measurements were completed.
The numbers of participants with high blood pressure declined in
all three groups, but the reduction was greater in the intervention
groups and most striking in the intervention group that included
the DASH eating plan. While approximately 37 percent of participants
in all three groups had high blood pressure at the study’s
start, this was reduced to 22 percent in the group following DASH
and 24 percent in the intervention group without DASH. By comparison,
the rate of hypertension fell only to 32 percent in the control
group.
“Participants in the two intervention groups made greater
changes than those in the control group and saw the greatest benefit
in blood pressure status,” said Eva Obarzanek, Ph.D., research
nutritionist and study co-author. “This shows that people
at risk for heart disease can successfully and simultaneously make
multiple changes in lifestyle, for a substantial benefit.”
Goals for the intervention groups included a 15 lb weight loss
(95 percent of participants were overweight or obese), 3 hours per
week of moderate physical activity, daily sodium intakes of no more
than 2300 milligrams (1 tsp salt), and limits of one alcoholic drink
per day for women, and two per day for men. Those also following
the DASH diet were asked to increase their consumption of fruits
and vegetables to 9-12 servings per day, consume 2-3 servings of
low-fat dairy products, and keep total fat to no more than 25 percent
of total daily calories. To keep track, participants kept food diaries,
monitored calories and sodium intakes, and recorded minutes of physical
activity.
More than one-third of participants had high blood pressure at
the beginning of the study. Of these, 62 percent in the intervention
group with DASH, and 60 percent in the intervention group without
DASH successfully had their blood pressure under control after 18
months (that is, their blood pressure levels were no longer considered
high). Comparatively, only 37 percent of the control group with
hypertension at the study’s start had their blood pressure
under control at the end of the study.
“These rates of hypertension control produced by the two
interventions are even better than the 50 percent control rates
typically found when single drug therapy is used to control high
blood pressure,” said William M. Vollmer, Ph.D., a study investigator
from Kaiser Permanente Center for Health Research.
Compared with the control group, one or both intervention groups
had:
- Greater weight loss: 5.9 lb in the DASH group and 4.8 lb in
the group without DASH.
- Greater improvement in fitness: 2 beats per minute lower heart
rate for the DASH group and 1 beat per minute lower heart rate
for those without DASH. (The greater the reduction in heart rate,
the greater the improvement in fitness.)
- Greater sodium reduction: 354 milligrams for those on the DASH
eating plan and 384 milligrams without DASH (about 1/6 tsp less
salt).
- Greater reductions in calorie intake: the intervention groups
reduced their daily intake by 95 (DASH) and 130 calories (without
DASH).
In addition, 25 percent of intervention group participants met
the weight loss goal. The group following DASH also achieved increased
fruit, vegetable, dairy, fiber and mineral intakes and decreased
fat intake.
The 6-months results of PREMIER results were reported in April
2003 in the Journal of the American Medical Association.
To interview a scientist about this study, please contact the NHLBI
Communications Office, (301) 496-4236 or nhlbi_news@nhlbi.nih.gov.
To reach Dr. Lawrence J. Appel, call David Marsh in the Johns Hopkins
Office of Communications and Public Affairs at (410) 955-1534; for
Dr. David W. Harsha, Louisiana State University, call (225) 763-0929;
for Dr. Laura P. Svetkey, Duke University Medical Center contact
the Duke Medical Center Public Relations Office at (919) 684-4148;
for Dr. William Vollmer, and Dr. Victor J. Stevens at Kaiser Permanente
Center for Health Research in Portland, OR, which served both as
a clinical center and as the PREMIER coordinating center, call Terry
Fitzpatrick at the Press Office at (503) 335-6602.
Part of the National Institutes of Health, the National Heart,
Lung, and Blood Institute (NHLBI) plans, conducts, and supports
research related to the causes, prevention, diagnosis, and treatment
of heart, blood vessel, lung, and blood diseases; and sleep disorders.
The Institute also administers national health education campaigns
on women and heart disease, healthy weight for children, and other
topics. NHLBI press releases and other materials are available online
at: www.nhlbi.nih.gov.
The National Institutes of Health (NIH) — The Nation's
Medical Research Agency — includes 27 Institutes and Centers
and is a component of the U. S. Department of Health and Human Services.
It is the primary federal agency for conducting and supporting basic,
clinical, and translational medical research, and it investigates
the causes, treatments, and cures for both common and rare diseases.
For more information about NIH and its programs, visit http://www.nih.gov.
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