Immune profiling in Puerto Rican injection drug users with and without HIV-1 infection

Gut microbiota profiling in injection drug users with and without HIV-1 infection in Puerto Rico

Introduction

The full extent of interactions between human immunodeficiency virus (HIV) infection, injection drug use, and the human microbiome is unclear. In this study, we examined the microbiomes of HIV-positive and HIV-negative individuals, both drug-injecting and non-injecting, to identify bacterial community changes in response to HIV and drug use. We utilized a well-established cohort of people who inject drugs in Puerto Rico, a region with historically high levels of injection drug use and an HIV incidence rate disproportionately associated with drug use.

Methods

Using amplicon-based 16S rDNA sequencing, we identified amplicon sequence variants (ASVs) that demonstrated significant variations in the composition of microbial communities based on HIV status and drug use.

Results and discussion

Our findings indicate that the HIV-positive group exhibited a higher abundance of ASVs belonging to the genera Prevotella, Alloprevotella, Sutterella, Megasphaera, Fusobacterium, and Mitsuokella. However, Bifidobacteria and Lactobacillus ASVs were more abundant in injectors than in non-injectors. We examined the effect of drug use on the gut microbiome in both HIV-infected and non-infected patients, and found that multiple drug use significantly affected the microbial community composition. Analysis of differential of bacterial taxa revealed an enrichment of Bifidobacterium spp., Faecalibacterium spp., and Lactobacillus spp. in the multiple drug-injecting group. However, in the non-injecting group, Parabacteroides spp., Prevotella spp., Paraprevotella spp., Sutterella spp., and Lachnoclostridium spp. The presence of multiple drug-injecting groups was observed to be more prevalent. Our findings provide detailed insight into ASV-level changes in the microbiome in response to HIV and drug use, suggesting that the effect of HIV status and drug injection may have different effects on microbiome composition and in modulating gut bacterial populations.

Cognitive Intraindividual variability in injection drug use among Hispanic residents of Puerto Rico

Despite a high prevalence of injection drug use (IDU) in Puerto Rico, little is known about how it affects neuropsychological functioning in this population. Investigations of intra-individual variability (IIV) have alluded to its utility as a potential indicator of neural decline. The purpose of this study was to characterize IIV among Hispanic residents of Puerto Rico who engage in IDU. Injectors and non-injectors completed the Neuropsí Atención y Memoria battery. Measures of IIV were calculated for the overall test battery (OTB), the three battery indices, and three domains of attention, memory, and executive functioning. The injector group showed significantly greater IIV than the non-injector group on all measures (OTB, indices, and individual domains). Additionally, injectors showed significantly higher IIV in the domain of executive functioning compared to other cognitive domains and battery indices. In contrast, non-injectors did not show any significant within-group differences on any IIV measures. The higher performance variability observed in the IDU group suggests a negative influence of IDU on cognition, with executive functioning being more susceptible to these effects. These findings support the need for continued investigations into the clinical application of IIV for diagnostic and prognostic purposes in the Hispanic IDU population.