Association of vitamin B12 mediated hyperhomocysteinemia with depression and anxiety disorder: A cross-sectional study among Bhil indigenous population of India.

BACKGROUND: Indigenous populations in India are amongst the poorest and most marginalized population groups experiencing severe health deprivation. AIM: The present study is the first study that aims to understand the association of micronutrient deficiencies (vitamin B12 and folate) and MTHFR C677T gene polymorphism with depression and generalized anxiety disorder (GAD) among the Bhil indigenous population of India. METHODS: A total of 303 participants aged 25-65 years of both sexes and unrelated up to first cousins belonging to Bhil indigenous population were recruited for the present study. Depression and generalized anxiety disorder were assessed using Patient Health Questionnaire and Generalized Anxiety Disorder scale, respectively. Biochemical analysis, DNA extraction and MTHFR C677T gene polymorphism analysis were done using standard protocols. RESULTS: Although, vitamin B12 and folate status was not found to be directly associated with depression and GAD, but hyperhomocysteinemia was posing more than three folds and six folds significant increased risk for depression and GAD, respectively. Further, it seems hyperhomocysteinemia was mediated by vitamin B12 deficiency among depressed and anxious individuals. T allele of MTHFR C677T gene polymorphism was posing increased risk for depression and anxiety disorder though not significant. CONCLUSION: The present study highlights the significance of micronutrient deficiencies in the causation of depression and anxiety disorder.