Assessing the effects of supplementation of vitamins on schizophrenia using Mendelian randomization analysis

ObjectiveVitamins are essential for human health and the prevention of diseases. They play an important role in maintaining brain function and mental health, especially in patients with schizophrenia. We aimed to evaluate the potential effects of genetic signatures predicting the intake of several vitamins on the risk of schizophrenia.MethodsTwo-sample Mendelian randomization analysis was used to evaluate the potential causal effects of the intake of seven vitamins (vitamins A-E, multivitamins, and folate) on schizophrenia. Genome-wide association study datasets were used for schizophrenia as the outcome. Weighted median, Mendelian randomization-Egger, and leave-one-out analyses, as well as Mendelian randomization pleiotropy residual sum and outlier, were used as supplementary methods to assess sensitivity.ResultsOur results found that genetic signatures promoting supplementary intake of folate (odds ratio = 0.00, 95% confidence interval: 0.00-0.12, p = 3.56E-3), vitamin C (odds ratio = 0.09, 95% confidence interval: 0.01-0.68, p = 0.019), vitamin D (odds ratio = 0.04, 95% confidence interval: 0.01-0.26, p = 6.48E-4), and vitamin E (odds ratio = 0.02, 95% confidence interval: 0.00-0.88, p = 0.043) were associated with a reduced risk of schizophrenia.ConclusionsOur study revealed the potential impacts of vitamin supplements on schizophrenia, providing evidence for vitamin-based supplementary treatment for the illness.