Context: Therapeutic effect of yoga in depression is recognized. Neuroplastic effects of antidepressant therapies are inferred by elevations in brain-derived neurotrophic factor (BDNF). Role of yoga in both these effects has not been studied.
Materials and methods: Non-suicidal, consecutive out-patients of depression were offered yoga either alone or with antidepressants. The depression severity was rated on Hamilton Depression Rating Scale (HDRS) before and at 3 months. Serum BDNF levels were measured at the same time points. Repeated-measures analysis of variance was performed to look at change across groups with respect to HDRS scores and BDNF levels over 3 months of follow-up. Relationship between change in serum BDNF levels and change in HDRS scores was assessed using the Pearson's correlation coefficient.
Results: Both yoga groups were better than drugs-only group with respect to reduction in HDRS scores. Serum BDNF rose in the total sample in the 3-month period. This was not, however, different across treatment groups. There was a significant positive correlation between fall in HDRS and rise in serum BDNF levels in yoga-only group (r=0.702; P=0.001), but not in those receiving yoga and antidepressants or antidepressants-alone.
Conclusions: Neuroplastic mechanisms may be related to the therapeutic mechanisms of yoga in depression.
Keywords: Antidepressant; brain-derived neurotrophic factor; depression; neuroplasticity; yoga.