Comparative Analysis of Fecal Microbiota Between Adolescents with Early-Onset Psychosis and Adults with Schizophrenia

Studies of the composition of the gut microbiome have consistently shown that psychiatric disorders such as schizophrenia are associated with gut dysbiosis. However, research focusing on adolescents with early-onset psychosis remains limited. This study aimed to characterize the microbial communities and their potential metabolic functions in these populations. We identified that genera <i>Desulfovibrionaceae_Incertae_Sedis</i>, <i>Paraprevotella</i>, and several genera from the Oscillospiraceae family were significantly more abundant in patients with schizophrenia compared to non-psychotic individuals, while <i>Dorea</i> showed decreased levels in schizophrenia patients. Furthermore, patients with early-onset psychosis demonstrated a significant reduction in <i>Staphylococcus</i> abundance. Additionally, we observed an increase in <i>Prevotellaceae Leyella</i> and <i>Prevotellaceae Incertae Sedis</i> in patients receiving atypical antipsychotic treatment, along with a rise in the genus <i>Weissella</i> among those treated with sertraline. Conversely, patients on valproate treatment exhibited decreased levels of <i>Desulfovibrionaceae Incertae Sedis</i>, while showing increased levels of <i>Kandleria</i> and <i>Howardella</i>. Functional prediction analysis using PICRUSt2 revealed significant differences in the expression of key enzymes associated with fatty acid metabolism. Gene orthology analysis identified 10 differentially expressed genes in the early-onset psychosis and schizophrenia groups. Our findings underscore the importance of considering dietary factors, pharmacological treatments, and microbial composition in understanding the gut-brain axis in psychiatric disorders.