Meditation Lowers Biomarkers of Stress

Mindfulness meditation is an increasingly popular treatment for anxiety, but testing its effectiveness in a convincing way has been difficult. Now a rigorously designed, NIH-sponsored clinical trial has found objective physiological evidence that mindfulness meditation combats anxiety.

The researchers found that anxiety disorder patients had sharply reduced stresshormone and inflammatory responses to a stressful situation after taking a mindfulness meditation course— whereas patients who took a non-meditation stress management course had worsened responses.

“Mindfulness meditation training is a relatively inexpensive and low-stigma treatment approach, and these findings strengthen the case that it can improve resilience to stress,” says lead author Elizabeth A. Hoge, MD, associate professor in Georgetown University Medical Center’s Department of Psychiatry.

The study, published January 24 in Psychiatry Research, included 89 patients with generalized anxiety disorder, a condition of chronic and excessive worrying. The disorder is estimated to affect nearly 7 million Americans during any one year.

One group of patients took an eight-week mindfulnessbased stress reduction course, while the control group took an eight-week stress management education course on the importance of nutrition, sleep, and other wellness topics. Both courses had similar formats, but only the former included training in meditative techniques.

Before and after the training course, participants underwent the Trier Social Stress Test, a standard experimental technique for inducing a stress response: the participants are asked at short notice to give a speech before an audience, and are given other anxietyinducing instructions.

“We were testing their resilience,” Hoge says, “because that’s really the ultimate question—can we make people handle stress better?”

For the stress test, the team monitored blood-based markers of subjects’ stress responses, namely levels of the stress hormone ACTH and the inflammatory proteins IL-6 and TNF-α. The control group showed modest rises on the second test compared to the first, suggesting a worsening of their anxiety from having to endure the test again. By contrast, the meditation group showed big drops in these markers on the second test, suggesting that the meditation training had helped them cope.

Hoge conducted the study while a postdoctoral researcher at Massachusetts General Hospital.