Capturing the antibiotic resistome of preterm infants reveals new benefits of probiotic supplementation.

BACKGROUND: Probiotic use in preterm infants can mitigate the impact of antibiotic exposure and reduce rates of certain illnesses; however, the benefit on the gut resistome, the collection of antibiotic resistance genes, requires further investigation. We hypothesized that probiotic supplementation of early preterm infants (born < 32-week gestation) while in hospital reduces the prevalence of antibiotic resistance genes associated with pathogenic bacteria in the gut. We used a targeted capture approach to compare the resistome from stool samples collected at the term corrected age of 40 weeks for two groups of preterm infants (those that routinely received a multi-strain probiotic during hospitalization and those that did not) with samples from full-term infants at 10 days of age to identify if preterm birth or probiotic supplementation impacted the resistome. We also compared the two groups of preterm infants up to 5 months of age to identify persistent antibiotic resistance genes. RESULTS: At the term corrected age, or 10 days of age for the full-term infants, we found over 80 antibiotic resistance genes in the preterm infants that did not receive probiotics that were not identified in either the full-term or probiotic-supplemented preterm infants. More genes associated with antibiotic inactivation mechanisms were identified in preterm infants unexposed to probiotics at this collection time-point compared to the other infants. We further linked these genes to mobile genetic elements and Enterobacteriaceae, which were also abundant in their gut microbiomes. Various genes associated with aminoglycoside and beta-lactam resistance, commonly found in pathogenic bacteria, were retained for up to 5 months in the preterm infants that did not receive probiotics. CONCLUSIONS: This pilot survey of preterm infants shows that probiotics administered after preterm birth during hospitalization reduced the diversity and prevented persistence of antibiotic resistance genes in the gut microbiome. The benefits of probiotic use on the microbiome and the resistome should be further explored in larger groups of infants. Due to its high sensitivity and lower sequencing cost, our targeted capture approach can facilitate these surveys to further address the implications of resistance genes persisting into infancy without the need for large-scale metagenomic sequencing. Video Abstract.

Infants' First Solid Foods: Impact on Gut Microbiota Development in Two Intercontinental Cohorts.

The introduction of solid foods is an important dietary event during infancy that causes profound shifts in the gut microbial composition towards a more adult-like state. Infant gut bacterial dynamics, especially in relation to nutritional intake remain understudied. Over 2 weeks surrounding the time of solid food introduction, the day-to-day dynamics in the gut microbiomes of 24 healthy, full-term infants from the Baby, Food & Mi and LucKi-Gut cohort studies were investigated in relation to their dietary intake. Microbial richness (observed species) and diversity (Shannon index) increased over time and were positively associated with dietary diversity. Microbial community structure (Bray-Curtis dissimilarity) was determined predominantly by individual and age (days). The extent of change in community structure in the introductory period was negatively associated with daily dietary diversity. High daily dietary diversity stabilized the gut microbiome. Bifidobacterial taxa were positively associated, while taxa of the genus Veillonella, that may be the same species, were negatively associated with dietary diversity in both cohorts. This study furthers our understanding of the impact of solid food introduction on gut microbiome development in early life. Dietary diversity seems to have the greatest impact on the gut microbiome as solids are introduced.

Aim2Be mHealth intervention for children with overweight and obesity: study protocol for a randomized controlled trial.

BACKGROUND: The prevalence of overweight and obesity remains high in Canada, and the current standard for the treatment of childhood obesity is in-person, family-based, multidisciplinary interventions that target lifestyle behaviors (e.g., diet, physical activity, and sedentary behaviors). These programs are costly to operate, have limited success, and report recruitment and retention challenges. With recent advances in technology, mobile health or mHealth has been presented as a viable alternative to in-person interventions for behavior change, especially with teens. PURPOSE: The primary aim of this study is to test the efficacy of Aim2Be, a gamified app based on behavior change theory with health coaching to improve weight outcomes (i.e., decrease in standardized body mass index (zBMI)) and lifestyle behaviors (i.e., improve dietary quality, increase fruit and vegetable intake, reduce sugar-sweetened beverage intake, increase physical activity, and reduce screen time) among children 10- to 17-years old with overweight or obesity versus their peers randomized into a waitlist control condition. The secondary aims of this study are to 1) test whether supplementing the Aim2Be program with health coaching increases adherence and 2) examine the mediators and moderators of adherence to the Aim2Be intervention. METHODS: We will employ a randomized controlled trial design and recruit 200 child and parent dyads to participate in the study (2019-2020). Participants will be recruited from Canadian pediatric weight management clinics and through online advertisements. Child participants must be between the ages of 10 and 17 years, have overweight or obesity, be able to read English at least at a grade 5 level, and have a mobile phone or home computer with internet access. Following baseline data collection, participants will be randomized into intervention and waitlist control groups. Intervention participants will receive access to Aim2Be, with access to health coaching. After having their data collected for 3 months, the control group will gain access to Aim2Be, with no access to health coaching. Participants will control their frequency and duration of app usage to promote autonomy. DISCUSSION: Findings from this study will determine the efficacy of using Aim2Be in improving child weight outcomes and lifestyle behaviors and guide future mHealth interventions for pediatric weight management. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03651284. Registered 29 August 2018.