Researchers are reporting that an intensive lifestyle modification program that includes the DASH diet combined with exercise can significantly reduce blood pressure in patients with “resistant” hypertension, one of the most difficult forms of high blood pressure to treat. Their study, funded by the NHLBI, appeared in the journal Circulation.
Researchers have known for some time that diet and exercise are effective in lowering high blood pressure in people with unmedicated hypertension and “uncontrolled” hypertension (130 millimeters of mercury (mm Hg). But the value of this intervention for lowering blood pressure in those with “resistant” hypertension—which often requires three or more antihypertensive medications to treat—remained unknown. Resistant hypertension is more severe than uncontrolled hypertension and carries a much higher risk for heart disease and death. It is estimated to affect 20% to 30% of hypertensive adults.
To find out whether lifestyle interventions will work for those with resistant hypertension, researchers developed the TRIUMPH randomized clinical trial (Treating Resistant Hypertension Using Lifestyle Modification to Promote Health). It is believed to be the first trial of its kind for this group.
During the four-month trial, researchers followed 140 people with resistant hypertension. They were randomly assigned to two groups—90 received an intensive intervention of weekly dietary counseling using the DASH diet and exercise training delivered at a cardiac rehab facility, while 50 received a single informational session from a health educator and written guidelines on exercise, weight loss, and nutritional goals. Blood pressure readings were taken before and after the interventions. The population demographics included the following: average age of 63 years; 48% women, and 59% black; 31% with type 2 diabetes; 21% with chronic kidney disease.
The researchers found that those who underwent the clinic intervention experienced the greatest reduction in systolic blood pressure levels. On average, the clinic intervention reduced systolic blood pressure levels (top pressure reading) by 12 mm Hg compared with reductions of 7 mm Hg in the self-guided group. In addition, 24-hour ambulatory blood pressure was significantly reduced in the clinic group, compared to no change in this particular measurement in the counseling group. Participants in the clinic group also experienced greater improvements in other key indicators of heart health, including certain cardiovascular disease biomarkers, the researchers said.