Poster Topical Area: Nutritional Microbiology
Poster Board Number: 245
Objective: To characterize the gut microbiota and dietary quality in an understudied group of Caribbean Latino adults at high risk for diabetes.
Methods: 17 participants from the Lawrence Senior Center enrolled in a feasibility study. Demographics and self-reported diabetes were collected by questionnaire. Diet was assessed by the average of two 24-hour dietary recalls. Dietary quality was assessed by the Healthy Eating Index (HEI) 2015. Inflammation was measured by serum C-reactive protein. Stool samples were placed at -80°C within 24h of collection. DNA was isolated and amplification of the V4 region of the 16S rRNA was performed on the Illumina MiSeq platform. Data processing and analyses performed in USEARCH 10 and QIIME 1.9.0. Variables dichotomized at the median (low/high) were compared to bacterial taxa abundance.
Results: Average age was 63.0 ± 8.1y (range: 51-76); 29% male, 41% with diabetes. Individuals with diabetes exhibited lower α-diversity (chao1, p=0.07). Cluster separation by diabetes status was observed using jaccard coefficient (PERMANOVA, p=0.1). No microbiota differences were observed between participants exhibiting high (n=5; >3mg/dL) or low inflammation. Subjects with low HEI scores showed a 2.84-fold increase of Proteobacteria (Bonferroni p=0.52). Individual dietary components showed subjects consuming: 1) high insoluble fiber (≥70% of total fiber) with higher α-diversity (chao1, p=0.4) and lower abundance of Lentisphaerae and Firmicutes (Bonferroni p < 0.3); 2) high sodium with higher abundance of Lentisphaerae and lower abundance of Bacteroidetes; 3) high sugar with higher abundance of Firmicutes, higher Lentisphaerae, and higher Verrucomicrobia (Bonferroni p<0.5).
Conclusions: Aging Caribbean Latino adults with diabetes exhibit gut dysbiosis characterized by decreased microbiota diversity. Poor dietary quality in this population correlates with higher Firmicutes, which has been associated with obesity. Interestingly, Verumicrobia and Lentisphaerae species are usually represented in lower abundance (studies in Caucasian populations) and little is known about their contribution to health. A larger sample size and in-depth sequencing is needed to advance study on the relation between health, diet, microbiome in Caribbean Latinos.
University of Massachusetts, Lowell