Antidepressant usage is associated with alterations in gut microbiota diversity and abundance in Parkinson’s Disease patients

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by motor dysfunction with co-presentation of neuropsychiatric and gastrointestinal symptoms prior to therapeutic treatments. Studies have established a relationship between PD and gut microbiome dysbiosis. Furthermore, recent studies show a relationship between mental health disorders and gut microbiome dysbiosis. Little is known on how the presence of neuropsychiatric disorders in PD patients can impact the gut microbiome in the absence of PD medication or gastrointestinal disorders. In this study, we first aimed to determine if antidepressant usage in PD patients was associated with alterations in the gut microbiota of PD patients. We then further investigated differences in gut microbiome profiles between PD patients who use antidepressants and those who do not. Our results indicate a significant difference in the beta diversity of microbiomes between PD patients who take antidepressants compared to those who do not. We further show that lower alpha diversity is present in groups that used antidepressants, and that antidepressant use was linked to enrichment of certain bacterial and archaeal families associated with gut dysbiosis in both PD and control groups. Finally, we show that PD subjects who used antidepressants were associated with a lower abundance of the Prevotellaceae bacterial family compared to PD patients who did not use antidepressants. This research can allow us to further understand associations between the presence of PD neuropsychiatric disorders and the gut microbiome of PD patients and, in turn, have clinical implications in the treatment of neuropsychiatric illnesses in PD.