Cortisol and antidepressant effects of yoga

CONTEXT: Hypercortisolemia is well-known in depression and yoga has been demonstrated earlier to reduce the parameters of stress, including cortisol levels. AIM: We aimed to find the role of yoga as an antidepressant as well as its action on lowering the serum cortisol levels. SETTINGS AND DESIGN: An open-labeled study consisting of three groups (yoga alone, yoga along with antidepressant medication and antidepressant medication alone) was conducted at a tertiary care psychiatry hospital. METHODOLOGY: Out-patient depressives who were not suicidal were offered yoga as a possible antidepressant therapy. A validated yoga module was used as therapy taught over a month and to be practiced at home daily. Patients were free to choose the drugs if their psychiatrist advised. Patients (n=54) were rated on Hamilton Depression Rating Scale (HDRS) with serum cortisol measurements at baseline and after 3 months. In 54 patients, assessments and blood test results were both available. 19 each received yoga alone or with drugs and 16 received drugs only. Healthy comparison subjects (n=18) too underwent morning cortisol measurements once. RESULTS: Serum cortisol was higher in depressives compared with controls. In the total sample, the cortisol level dropped significantly at the end of treatment. More patients in the yoga groups had a drop in cortisol levels as compared to drug-only group. In the yoga-only group, the cortisol drop correlated with the drop in HDRS score (antidepressant effect). CONCLUSION: The findings support that yoga may act at the level of the hypothalamus by its ‘anti-stress’ effects (reducing the cortisol), to bring about relief in depression.