Poster Topical Area: Obesity

Location: Hall D

Poster Board Number: 622

E02-01 - Diet Quality and Obesity Impact Gut Microbial Composition in Older Adults Living with HIV

Sunday, Jun 10
8:00 AM – 6:00 PM

Objectives: HIV infection alters composition of gut microbiota. However, investigations of HIV infection and the gut microbiome have not considered the contributions of dietary intake and obesity to microbial diversity. Our objective was to demonstrate how response to HIV antiretroviral therapy (CD4+ T-cell count), dietary intake, and obesity (BMI≥30) impact the microbiome in adults with HIV age >50 years, who are considered older adults in the HIV community due to possible accelerated aging.

We recruited 60 HIV-infected persons ≥ 50 years old with controlled viremia for > 1 year. Groups were determined based on a CD4+ count either 500 (high, n=30) c/mm3, and a BMI ≥30 (obese) or below 30 (not obese): (1) Low CD4/Not Obese; (2) Low CD4/Obese; (3) High CD4/Not Obese; (4) High CD4/Obese. Participants had no underlying GI disease or antibiotic use for 60 days pre-enrollment. Dietary intake was assessed as the average of three 24-hour diet recalls. Fecal microbiome was analyzed using 16S rRNA gene sequencing using MiSeqTM and QIIME bioinformatics.

Median age was 56 years (range 50-72); 30% were women; median BMI was 28 kg/m2. A negative correlation was observed between BMI>30 and diversity (Shannon r = -0.24, P=0.11; Simpson r = -0.23, P = 0.04). A low CD4 count was associated with increased Synergistetes and decreased Bifidobacteriales. Protein intake adjusted for body weight was positively correlated with Fusobacteria and Prevotella OTUs. Participants in the High CD4/Not Obese group had higher Bacteroidetes and lower Firmicutes composition compared to both Obese/CD4 groups (both P<0.05), while the Low CD4/Not Obese group had Bacteroidetes and Firmicutes composition similar to both Obese groups<./p>

In this preliminary study, the gut microbiome of obese adults with HIV were less diverse, while dietary protein intake impacts gut microbiome composition even in the presence of HIV infection. However, HIV-1 infected individuals in the Low CD4/Not Obese group display a gut microbe profile similar to HIV-infected obese persons. Understanding the relationship between body weight, gut microbe composition, and chronic viral infection will facilitate the development of novel interventions for gut dysbiosis and its consequences in people living with HIV.

Funding Source: NIAID Center for AIDS Research P30-AI27767
NIAID R24-AI067039-1
Mary Fisher Care Fund

CoAuthors: Casey Morrow, PhD – University of Alabama at Birmingham; Martin Rodriguez, MD – University of Alabama at Birmingham; Edgar Overton, MD – University of Alabama at Birmingham

Amanda L. Willig

Assistant Professor
University of Alabama at Birmingham
Birmingham, Alabama