By Kathleen Raven
NEW YORK (Reuters Health) - Stress reduction exercises have been linked to many health benefits, but lower blood pressure may not be one of them.
A new study found eight weeks of mindfulness meditation had no effect on people with slightly elevated blood pressure who were not yet taking medication.
"This doesn't mean that meditation is bad. It just simply doesn't lower blood pressure," senior author Dr. Sheldon Tobe of Sunnybrook Health Sciences Centre in Toronto, said.
He said he was expecting to see an effect on blood pressure based on past studies showing benefits with mindfulness meditation. But when he looked back over those earlier trials, Tobe found the majority of participants had been taking blood pressure-lowering drugs.
In those studies, mindfulness therapy could have worked by helping people take their medicine more consistently, Tobe explained.
"Few interventions are as powerful as medication," he told Reuters Health. "You can reduce salt intake or lose weight and help lower blood pressure, but high blood pressure medication has a more powerful effect."
One in three U.S. adults has high blood pressure, according to the Centers for Disease Control and Prevention.
The National Heart, Lung, and Blood Institute considers 140/90 millimeters of mercury (mm Hg) and above to be high blood pressure.
The 101 participants in the new study had an average blood pressure of 135/82 mm Hg, which is considered above normal but not yet classified as high blood pressure.
Half of them were assigned to start the mindfulness-based stress reduction (MBSR) therapy right away and the rest were wait-listed to take the class at a later time.
Mindfulness participants went to eight weekly group sessions and attended a day-long silent retreat. Each person was also asked to practice stress reduction for 45 minutes daily.
The study participants, aged 20 to 75, were all counseled with standard high blood pressure advice: eat less salt, quit smoking and exercise more.
At the end of the study period, both people who had gone through the mindfulness program and those on the wait list saw virtually no change in their blood pressure, according to findings published in the American Journal of Hypertension.
Physical therapy researcher Marshall Hagins of Long Island University in Brooklyn said he was disappointed with the results, but only because he wanted the program to show benefits.
"MBSR does lots of positive things, however, if you are an individual with stage one hypertension not currently on medication, and lowering your blood pressure is your goal, then MBSR may not be the optimal program," Hagins said.
"It's important to remember that this study was limited to a highly standardized stress reduction program, and the results do not apply to other techniques," he told Reuters Health. Some examples include Tai Chi and Transcendental Meditation.
A 2007 summary report published by the U.S. Agency for Healthcare Research and Quality found Zen Buddhist meditation and Qi Gong significantly reduced blood pressure.
But Tobe said in his mind, the study results could be the final answer to the question regarding this particular population and method of stress reduction.
Stress reduction exercises like gentle stretching, mindful breathing and walking do not pose any harm to people with early-stage hypertension, he noted.
Within the study, a minority of participants reported dissatisfaction with the mindfulness meditation classes and exercises. Most reported that they felt better.
"If quality of life is improved by mindfulness meditation - that's fabulous," Tobe said.
He stressed that people who are worried about their blood pressure should see their family doctor.
SOURCE: bit.ly/1fIPOpT American Journal of Hypertension, online September 14, 2013.