Dynamic Dysbiosis of Maternal Gut Microbiome in Perinatal Anxiety

Anxiety and depression are some of the most common psychiatric disorders during the perinatal period (pregnancy and up to one year postpartum). About 20% of women suffer from one or more anxiety disorders during pregnancy or postpartum. Most of the earlier research focuses on determining the differences in the gut microbiota of individuals suffering from Generalized Anxiety Disorder in the non-pregnant population. However, perinatal anxiety is associated with various risk factors and has negative consequences on infants, so it is necessary to understand the role of gut microbiota in perinatal anxiety. Anxiety is also associated with inflammatory states, which are characterized by the activity of the immune system through cytokines and associated with the gut microbiota. We have identified microbial taxa associated with the activity of the autonomic nervous system by using Heart Rate Variability as a proxy during the postpartum period as the gut and brain communicate through the autonomic nervous system. Fecal and blood samples were collected from the participants during the perinatal period. Participants were 75% White and on an average were about 34 years old and had more than 16 years of education. Participants completed self-reported mental health questionnaires related to anxiety, mood, and stress. Amplicon sequence variants were used to determine the associations using the generalized linear models. While we did not observe any significant association between richness (alpha-diversity) and structure level (beta-diversity) to anxiety levels and gestational weeks except for the postpartum period. The genera Alistipes was found to be negatively associated with anxiety, had associations with certain cytokines throughout the perinatal period, and was positively associated with HRV measures. Tryptamine, a precursor of serotonin, producing bacteria (e.g., Bifidobacterium, Blautia), and butyrate producing bacteria (e.g., Faecalibacterium) was also negatively associated with anxiety scores. Predicted metabolic pathways associated with neurotransmitter activation and degradation processes were not significantly different in individuals with active episodes of perinatal anxiety. The immune system is distinct in the third trimester of pregnancy and the postpartum period. Immunological differences were associated with microbial communities. We expect that our results could serve to develop novel microbial-inspired treatments for perinatal anxiety and to move into a precision medicine approach to treat this condition.