Yoga as a complementary therapy for clinical depression

The Behavioral Risk Factor Surveillance System in 2006 found that the prevalence of current depressive symptoms in general population was 8.7% and lifetime diagnosis of depression was 15.7% making it a common illness. Antidepressant medication is the primary treatment for depression. Yoga offers an attractive option for complementary therapy of depression. Yoga is an ancient system of physical and psychic practice that aims at maintaining harmony between self, society, and nature. The purpose of this study was to examine whether yoga is beneficial as a complementary therapy for depression or not. The method used in this study was a systematic qualitative review of interventions obtained from MEDLINE, CINAHL, & ERIC databases. The criteria for including studies were: publication in English language, publication between 2005 and 2009, studies that measured depression or depressive symptoms as an outcome, and studies that used yoga (from any school) as an intervention. A total of 18 studies met the criteria. These studies were from Brazil (1), Canada (1), India (6), Iran (1), Japan (1), Taiwan (1), and United States (7). Schools of yoga included Sudrashan Kriya Yoga (SKY), Iyengar yoga, Siddha Samadhi Yoga, Silver Yoga, and Sahaj Yoga. Some of the designs utilized by the interventions were pre-test post test, quasi experimental, and randomized controlled trials. It was found that majority of the interventions (17) were able to significantly reduce depressive symptoms in the patients under study. However several methodological limitations were identified in the conduct of the intervention trials which future interventions must consider.