ASPO Abstracts
Race, Neighborhood Socioeconomic Status, and Gut Microbiome
Category: Cancer Health Disparities
Conference Year: 2020
Abstract Body:
Purpose of the study:
Gut microbiome plays an increasingly recognized important role in human health. This study
aims to evaluate the association among race, neighborhood disadvantage index (NDI), and
gut microbiome in patients undergoing screening colonoscopy.
Methods:
The study includes 689 patients aged 50-80 years undergoing screening colonoscopy at
University Hospitals Cleveland Medical Center. Each patient donated a stool sample 1-4
weeks prior to their colonoscopy examination. 16S ribosomal RNA genes in stools were
sequenced and classified into 236 Operational Taxonomic Units (OTUs) to species level.
Neighborhood Disadvantage Index (NDI) was derived from 17 variables reflecting
neighborhood contextual environment. We first examined the association of race with
microbiota, and race with NDI. We then examined further the association between NDI and
each microbiota by linear mixed effect model to account for the correlation within census
tract, with adjustment of age, sex, BMI, smoking, and sequencing batch. The significance
of associations between microbiota and NDI are evaluated by likelihood ratio tests.
Q-value was estimated for False Discovery Rate (FDR)-based multiple testing correction.
For the microbiota associated with NDI with Q-value <= 0.05, we additionally adjusted for
genetic ancestry in the model in a subset of 222 patients who have available genome-wide
ancestry informative SNP genotype data.
Results:
Of all the 172 microbiota that have minimum relative abundances >.005, 13 microbiota were
significantly associated with race. We speculate that such association with race could be
at least partially driven by neighborhood socioeconomic environment – i.e., racialized
neighborhood environment - given the high correlation of race and NDI (corr = 0.60, p
=3.38E-56). Multivariate-adjusted regression models showed that 5 microbiota were
positively associated with NDI (Q-value < .05). Subset analysis of 222 patients with
further controlling for genetic ethnicity shows that two microbiotas remain significantly
associated with NDI.
Conclusions: Residential neighborhood disadvantage was found to impact gut microbiota.
Further studies to validate our findings and to delineate the functionality of these
NDI-associated microbiota are warranted.
Keywords: Microbiome, colon, neighborhood socioeconomic status, race