April 3, 2006

228 Portland-area adults participate in national study

Making longer-term lifestyle changes lowers rates of high blood pressure and risk of heart disease

PORTLAND, Ore. - April 3, 2006-Men and women with elevated blood pressure who make and sustain healthy lifestyle changes for up to a year and a half can substantially reduce their rates of high blood pressure and potentially decrease their heart disease risk. Results of the study, called PREMIER, show that rates of high blood pressure dropped from 37 percent to 22 percent among participants who received diet and physical activity counseling. Results of the study appear in the April 4th issue of Annals of Internal Medicine.

"These results contain two very good pieces of news for the millions of Americans who have elevated blood pressure," says William Vollmer, PhD, senior investigator at Kaiser Permanente's Center for Health Research and a study co-author. "Our previous research showed that making multiple lifestyle changes-eating a healthier diet and increasing physical activity-for a short-term period of six months led to significant reductions in blood pressure. Now we know that sustaining these lifestyle changes for the longer period of 18 months also leads to substantial blood pressure reductions. This is very good news because the longer people can keep their blood pressure down, the better it is for their heart health. The other good news is that this study shows that people can make and sustain these lifestyle changes over a fairly long time period."

The study, funded by the National Heart, Lung and Blood Institute (NHLBI), was conducted at four clinical centers at Duke University; Johns Hopkins University; Louisiana State University; and Kaiser Permanente's Center for Health Research, which also served as the coordinating center for the study.

A total of 810 men and women ages 25 and older with either prehypertension (120-139 mmHg / 80-89 mmHg) or stage 1 hypertension (140-159 mmHg / 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 four individual sessions. During the last 12 months, they attended 12 group meetings and three individual sessions. They were prescribed goals for weight loss and physical activity. They were also given sodium and alcohol intake limits. One of these groups also received guidance on following the DASH diet, an eating plan rich in fruits and vegetables, low-fat dairy products and low in saturated fat, total fat and dietary cholesterol. DASH stands for "Dietary Approaches to Stop Hypertension," a diet that substantially lowered blood pressure in a previous NHLBI-sponsored feeding study. DASH is used as an example of a healthy eating plan by the U.S. Dietary Guidelines for Americans.

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 six months later. A third session was offered at the end of the 18-month trial after measurements were completed.

Rates of high blood pressure declined in all three groups, but the reduction was greater in both 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 to only 32 percent in the control group.

Goals for the intervention groups included a 15-pound weight loss (95 percent of participants were overweight or obese), three 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 all 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 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," Vollmer says. "This is also good news for many people with high blood pressure because it means they may be able to control their hypertension without drugs or by reducing the number of drugs they take. However, we strongly advise patients taking hypertension drugs to consult with their physicians before trying to substitute lifestyle changes for their prescribed drugs."

Compared with the control group, one or both intervention groups had:

• Greater weight loss: 5.9 lbs. in the DASH group and 4.8 lbs. in the group without DASH.
• Greater improvement in fitness: two beats per minute lower heart rate for the DASH group and one 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 fat intake: the DASH group reduced fat calories by 6 percent, compared with 1.5 percent in the intervention group without DASH.
• 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.

Kaiser Permanente's Center for Health Research, founded in 1964, is a nonprofit research institution whose mission is advancing knowledge to improve health.

Kaiser Permanente is the nation's leading integrated health care organization. Founded in 1945, it serves more than 8.4 million people nationwide, including more than 485,000 in Oregon and Southwest Washington.

For more infomation contact:

Terry Fitzpatrick - 503-335-6602 or
Brad Brokaw 503-813-4820