Antidepressants are the main treatment for severe depression, yet more than half of the 41 million people in the United States who take them don't fully respond to the medications currently on the market. This set of depression sufferers also has a higher risk of relapse than others do. Clearly, they need another option, and the answer may be yoga, specifically yogic breathing, a new study from the University of Pennsylvania finds.

People whose depression had not been helped by medication saw their depression score improve over the course of the study by nearly 10 points after eight weeks of yoga. Depression scores among those not in the yoga group rose slightly over the same period.

A depression treatment that people can use at home has the potential to help a much greater number of people than one that requires doctor or hospital visits.

The yoga technique used in the study was Sudarshan Kriya Yoga (SKY), a breathing-based meditation technique. It relies on alternating cycles of slow, fast and medium speed breathing, with a chant interspersed. It can be done in both a group setting and alone at home.

The pilot study looked at 25 people with major depressive disorder who, despite taking an antidepressant for more than eight weeks, were still depressed. They were randomly divided into two groups, with half placed in the yoga group and half in the waitlist group.

The waitlist group was offered the breathing and yoga training at the end of the eight-week study.

During the first week, the yoga group completed a six-session program, which featured SKY as well as yoga postures, sitting meditation and stress education. For weeks two through eight, they attended weekly SKY follow-up sessions and also practiced SKY at home.

The yoga group started out with a Hamilton Depression score of 22.0, indicating severe depression. After the eight weeks of yoga, this score dropped — improved — by 9.77 points, while that of the waitlist group rose by 0.5 points. People in the yoga group also had significantly improved scores on the Beck depression (up 10.19 points) and Beck anxiety scales compared to those in the waitlist group.

Yoga and other controlled breathing techniques appear to change the nervous system so it produces fewer stress hormones. Yet, as the authors note, despite yoga's increasing popularity, there still aren't many well-designed studies that evaluate yoga's ability to treat depression. Most studies have been small, as was this one. The authors of the current research report are currently planning a larger trial of their own.

While a few previous studies have suggested that SKY could ease depression, the authors say this is the first clinical trial of SKY in an outpatient setting. A depression treatment that people can use at home has the potential to help a much greater number of people than one that requires doctor or hospital visits.

The study appears in the Journal of Clinical Psychiatry.