SUMMER 2023

Nicolas Mastrovito

Previous studies have quantified the level of antibiotic resistance genes (ARGs) in the gut microbiome of infants, but less studies of the same nature have been performed for elderly people. A healthy gut microbiome is critical for maintaining balanced immune and digestive health. While antibiotics are effective for the treatment of bacterial infections, they also disrupt the balance of the human gut microbiome and create a selective pressure that increases the prevalence of antibiotic-resistant microbes in the human gut. To improve the understanding of the presence of ARGs in the gut microbiome of elderly individuals, we used qPCR to quantify the level of several ARGs. Statistical analysis was performed to compare qPCR-determined levels of ARGs in fecal samples collected from four different populations, including a “young elderly” population (as a control group) and an elderly population from 2009 and 2023. The resulting data supported the hypothesis that elderly people aged greater than 80 years have different gut resistoma than younger elderly people aged 60-65 years. We also found that aging from 60-65 years to greater than 80 years is likely associated with change in resistoma, but the character of the change may depend on the individual. Furthermore, it was found that people greater than 80 years old have different resistoma in different moments of time (2009 and 2023). Finally, it was found that the resistoma changes within the same individuals as they age from 60-65 years to greater than 80 years. The character of this change is complex and requires further investigation.