HARMONY: Relaxation Therapy Does Not Lower BP in Mild Hypertension

Marlene Busko

November 05, 2012

TORONTO — For patients with mild hypertension who want to avoid taking pills and prefer to try to lower their blood pressure by doing yoga and meditating, results from the Hypertension Analysis of Stress Reduction Using Meditation and Yoga (HARMONY) trial are discouraging [1].

Even the researchers admit they were disappointed with the study findings. Among study participants with stage 1 hypertension, those who followed an intensive, 10-week mindfulness-based stress-reduction (MBSR) program did not attain better blood-pressure control.

Although previous studies showed that different types of stress-reduction techniques may lower blood pressure, those studies included patients who were also taking antihypertensives. This suggests that MBSR might be effective, but as an adjunct therapy.

"While it is disappointing that we didn't find a blood-pressure–lowering effect in the HARMONY trial of stage 1, unmedicated hypertensives, what these results do suggest is that maybe stress-reduction therapy should be tailored to subjects who are already being treated for their blood pressure," said Kimberly Blom (University of Toronto, ON), presenting the HARMONY results at a late-breaking-trial session here at the Canadian Cardiovascular Congress 2012.

The study was led by Dr Sheldon Tobe (Sunnybrook Health Sciences Centre, Toronto, ON).

Provincially Funded Stress-Reduction Therapy

The Ontario provincial government covers the cost of MBSR therapy to treat anxiety, depression, and chronic pain. Previous studies have suggested that blood pressure might be lowered by using cognitive behavioral therapy, transcendental meditation, or behavioral neurocardiac training.

As reported by heartwire , HARMONY was designed to test whether a group stress-reduction program could lower blood pressure in patients with stage 1, unmedicated hypertension.

The researchers recruited people who were 20 to 75 years old and lived in the Toronto area.

Of the 483 individuals who were screened, 382 were ineligible mainly because of recent use of antihypertensives. This left 101 study subjects--38 men and 63 women with an average age of 55 years.

At baseline, the subjects had an average daytime ambulatory blood pressure of >140/87 mm Hg and an average 24-hour ambulatory blood pressure of >135/82 mm Hg.

The participants were randomized to receive immediate stress-reduction therapy or to be on the waiting list for this therapy (control group).

They all received advice about making healthy lifestyle choices, as recommended by hypertension treatment guidelines.

The MBSR intervention, given by two trained therapists to groups of about 25 patients, consisted of:

  • An introductory class.

  • Eight weekly mindfulness sessions of two-and-a-half hours--where participants learned how to do yoga and meditate.

  • A full-day retreat.

  • 45 minutes of daily homework (meditation practice).

"What you can see is that this was a fairly substantial commitment," Blom said. "The idea behind MBSR is to teach subjects ways of incorporating mindfulness and stress-reduction therapies into their everyday activities," she noted.

The primary outcome was the change in the mean daytime and 24-hour blood-pressure measurement from baseline to 12 weeks in the treatment group vs the control group. Secondary outcomes included blood-pressure results at 24 weeks.

The study had an 81% power to detect a difference of 6 mm Hg, with 37 participants in each group.

The researchers did not find any significant differences between the treatment and the control group for any ambulatory blood-pressure parameters at 12 or 24 weeks, Blom reported.

The team is conducting a follow-up study to determine whether an MBSR program would improve blood-pressure control when it is combined with medication and whether this would improve adherence to medication.

"Wake-Up Call": Stress Reduction Alone "Doesn't Cut It"

"For that Canadian [or American] who is in a bit of denial as to whether to swallow pills or not--and there's a large group--it's a wake-up call," comoderator Dr John Mancini (St Paul's Hospital, Vancouver, BC) commented to heartwire .

He noted that in this study of patients with mild hypertension, all of the other traditional devices--advice to stop smoking, follow a healthy diet, and exercise--were at play. "Even when we add this sophisticated, nonmedicinal approach, it didn't really cut it," he said. MBSR therapy "might be an adjunct, but it should not be viewed as a primary intervention."

The research was supported by the Heart and Stroke Foundation of Ontario.