Improvement in neurocognitive functions and serum brain-derived neurotrophic factor levels in patients with depression treated with antidepressants and yoga.

ABSTRACT

CONTEXT AND AIMS: Impairment in cognition is well-known in patients with major depressive disorder. This study examined the effect of yoga therapy with or without antidepressants and antidepressants alone on certain neuropsychological functions in patients with depression. Correlation between changes in neuropsychological test performance and serum brain-derived neurotrophic factor (BDNF) levels was also explored. MATERIALS AND METHODS: Antidepressant-naïve/antidepressant-free outpatients with depression received antidepressant medication alone (n = 23) or yoga therapy with (n = 26) or without (n = 16) antidepressants. Depression was assessed using the Hamilton Depression Rating Scale. Neuropsychological tests included digit-span forward and backward, Rey Auditory Verbal Learning Test, and Trail Making Tests (TMT-A and B). These tests were administered before and 3 months after the treatment in patients, and once in healthy comparison subjects (n = 19). STATISTICAL ANALYSIS: Baseline differences were analyzed using independent sample t-test, Chi-square, and one-way ANOVA. Paired t-test was used to analyze the change from baseline to follow-up. Pearson's correlation was used to explore the association of change between 2 variables. RESULTS: Patients had impaired performance on most neuropsychological tests. After 3 months, there was significant improvement - patients' performance was comparable to that of healthy controls on majority of the tests. Significant inverse correlation was observed between increase in BDNF levels and improvement in TMT "A" duration in Yoga-alone group (r = -0.647; P = 0.009). CONCLUSIONS: To conclude that, Yoga therapy, alone or in combination with medications, is associated with improved neuropsychological functions and neuroplastic effects in patients with depression.