Oral and gut microbiome profiles in early Parkinson’s disease

Abstract

Abstract Early detection of Parkinson’s disease (PD), a neurodegenerative disease with central and peripheral nerve involvement, ensures timely treatment access. Microbes influence nervous system health and are altered in PD. We examined gut and mouth microbiomes from recently diagnosed patients in a geographically diverse, matched case-control, metagenomics study. We demonstrated greater alpha-diversity in 464 PD patients versus 249 controls. The microbial signature of PD included overabundance of 16 OTUs, including Streptococcus mutans and Bifidobacterium dentium, and depletion of 28 OTUs. Machine learning models indicated sub-species level oral microbiome abundances best distinguished PD with relatively high accuracy (area under the curve: 0.758). Microbial networks were disrupted in cases, with reduced connectivity of short-chain fatty acid-producing bacteria from stool. Microbiome diversity metrics associated with non-motor autonomic symptom severity. Our results provide evidence for predictive oral taxonomic PD microbiome signatures that may be useful for early detection, particularly with peripheral nervous system involvement.