Increased body mass is associated with decreased gut microbiome diversity in Parkinson’s Disease patients

Parkinson’s Disease is a common neurodegenerative disorder that results in both motor and non-motor symptoms. The subtle nature of early Parkinson’s Disease symptoms is often misinterpreted as normal signs of aging, and a lack of definitive tests to confirm Parkinson’s Disease contribute to diagnosis delays. Because gastrointestinal symptoms are often observed years before motor symptoms, previous studies have focused on the relationship between changes in the gut microbiota composition and the pathophysiology of Parkinson’s Disease. Previous findings have yielded conflicting results regarding effects of various lifestyle factors on gut microbiota of Parkinson’s patients. To investigate contradictions observed from previous studies, our study aims to determine effects of body mass index (BMI) levels, alcohol consumption, and meat consumption on the gut microbiota of Parkinson’s patients. Our results indicated that gut microbial diversity decreased in overweight and obese Parkinson’s patients compared to healthy Parkinson’s patients. There was no relationship between alcohol or meat consumption and gut microbiome composition of Parkinson’s patients. The Sutterallaceae and Veillonellaceae taxonomic families have been previously associated with obesity and diseases that have implications to the gut microbiota. Unique family taxa analysis determined that the Sutterellaceae family was more abundant in Parkinson’s Disease patients of the obese BMI grouping. Similarly, indicator taxa analysis determined two families were significantly associated to the obese BMI grouping, one of which being the Veillonellaceae family. These results indicate that changes in body mass may affect gut microbial composition and present relevant taxa to be further investigated for understanding the effect of body mass on Parkinson’s Disease.