Infants exposed to antibiotics after birth have altered recognition memory responses at one month of age.

BACKGROUND: Neonatal exposure to antibiotics, in the absence of infection, results in abnormal learning and memory in animals and is linked to changes in gut microbes. The relevance of early-life antibiotic exposure to brain function in humans is not known. METHODS: Recognition memory was assessed at 1 month of age in 15 term-born infants exposed to antibiotics (with negative cultures) and 57 unexposed infants using event-related potentials (ERPs). Linear regression analysis, adjusting for covariates, was employed to compare groups with respect to ERP features representing early stimulus processing (P2 amplitude) and discrimination between mother and stranger voices. RESULTS: Infants exposed to antibiotics exhibited smaller P2 amplitudes for both voice conditions (p = 0.001), with greatest reductions observed for mother's voice in frontal and central scalp regions (p < 0.04). Infants exposed to antibiotics showed larger P2 amplitudes to stranger's as compared to mother's voice, a reversal of the typical response exhibited by unexposed infants. Abnormal ERP responses did not consistently correlate with increased inflammatory cytokines within the antibiotic-exposed group. CONCLUSIONS: Otherwise healthy infants exposed to antibiotics soon after birth demonstrated altered auditory processing and recognition memory responses, supporting the possibility of a microbiota-gut-brain axis in humans during early life. IMPACT: Infants exposed to antibiotics after birth demonstrate altered auditory processing and recognition memory responses at 1 month of age. Preclinical models support a role for gut microbiomes in modulating brain function and behavior, particularly in developing brains. This study is one of the first to explore the relevance of these findings for human infants. The findings of this study have implications for the management and follow-up of at-risk infants with exposure to gut-microbiome disrupting factors and lay foundation for future studies to further characterize the short- and long-term effects of gut microbiome perturbation on brain development.

Overweight and obesity among children and adolescents with fetal alcohol spectrum disorders.

BACKGROUND: Because prenatal alcohol exposure is associated with growth deficiency, little attention has been paid to the potential for overweight and obesity in children with fetal alcohol spectrum disorders (FASD). This study examined the prevalence of overweight/obesity (body mass index [BMI]) in a large clinical sample of children with FASD. METHODS: Children, aged 2 to 19 years, who were evaluated for FASD at University Clinics, included 445 with an FASD diagnosis and 171 with No-FASD diagnosis. Prevalence of overweight/obesity (BMI ≥ 85 percentile) was compared to national and state prevalence. BMI was examined in relation to FASD diagnosis, gender, and age. Dietary intake data were examined for a young subsample (n = 42). RESULTS: Thirty-four percent with any FASD diagnosis were overweight or obese, which did not differ from the No-FASD group or U.S. prevalence. Underweight was prevalent in those with fetal alcohol syndrome (FAS) (17%). However, increased rates of overweight/obesity were seen in those with partial FAS (40%). Among adolescents, those with any FASD diagnosis had increased overweight/obesity (42%), particularly among females (50%). The rate in adolescent females with FASD (50%) was nearly 3 times higher than state prevalence for adolescent females (17 to 18%), p < 0.001. In the young subsample, those who were overweight/obese consumed more calories, protein, and total fat per day than those who were not overweight or obese. CONCLUSIONS: Rates of overweight/obesity are increased in children with partial FAS. In adolescents, rates are increased for any FASD diagnosis (particularly in females). Results are suggestive of possible metabolic/endocrine disruption in FASD-a hypothesis for which there is evidence from animal models. These data suggest that clinicians may consider prenatal alcohol exposure as a risk factor for metabolic/endocrine disruption, should evaluate diet as a risk in this population, and may need to target interventions to females prior to puberty to effect changes in overweight-related outcomes.

Ultrasound measurements of abdominal muscle thickness are associated with postmenstrual age at full oral feedings in preterm infants: A preliminary study.

BACKGROUND: A premature infant's discharge from the neonatal intensive care unit (NICU) is dependent on factors such as respiratory stability, adequate growth, and the ability to consume oral feeds. Once infants have achieved respiratory stability, a tool that can better predict age at discharge is desirable. Thus, we conducted a secondary data analysis to assess the association between ultrasound measurements of abdominal muscle thickness and postmenstrual age (PMA) at full oral feedings. METHODS: Forty-nine (n = 49) healthy, premature infants (mean gestational age = 32 weeks) were recruited from the NICU. Anthropometric measurements and ultrasound measurements of the rectus abdominis were conducted when infants were medically stable. Fat-free mass (FFM) was obtained using air displacement plethysmography. The relationship between ultrasound measurements of muscle thickness and PMA at full oral feedings was assessed using linear regression analysis. The relationship between FFM z-scores and PMA at full oral feedings was also assessed for comparison. RESULTS: When adjusting for gestational age at birth, PMA at measurement, days of positive pressure respiratory support, weight, and length, ultrasound measurements of abdominal muscle thickness were independently, negatively associated with PMA at full oral feedings (ß estimate: -0.71, P = .03). CONCLUSION: Preliminary results suggest infants with greater abdominal muscle thickness may reach full oral feedings at an earlier PMA (nearly 1 week per millimeter). Thus, ultrasound measurements of abdominal muscle thickness may be helpful in assessing readiness for discharge in healthy preterm infants. Further research is needed for development and validation of a prediction equation.

Can Ultrasound Measures of Muscle and Adipose Tissue Thickness Predict Body Composition of Premature Infants in the Neonatal Intensive Care Unit?

BACKGROUND: Premature infants are at risk for adverse metabolic and neurodevelopmental outcomes due to growth alterations in early infancy. Monitoring body composition by tracking gains in fat mass (FM) and fat-free mass (FFM) may assist clinicians in preventing obesity and metabolic disease while promoting optimal growth and development. A prospective, observational study was conducted to determine the ability of ultrasound (US) measurements of muscle and adipose tissue thickness to predict whole-body composition (FFM, FM, percent body fat [%BF]). METHODS: Sixty-three healthy premature infants were recruited from the University of Minnesota's Neonatal Intensive Care Unit. Anthropometric measurements, air displacement plethysmography, and US measurements of abdomen, biceps, and quadriceps muscle and of adipose tissue thickness were conducted when infants were medically stable. The relationship between US measurements and body composition was assessed using stepwise linear regression analysis. RESULTS: In linear regression analyses, biceps adipose and the sum of adipose thickness measurements were significant predictors of %BF, but prediction models had low R2 (0.17 and 0.16, respectively) and high root-mean-square error. US measurements of muscle thickness were not predictive of whole-body FFM. CONCLUSION: US measurements of muscle and adipose tissue thickness at the examined sites are not adequate surrogates for whole-body composition in preterm infants. Exploration of alternate measurement sites may improve predictive ability.

Clinical Application of Body Composition Methods in Premature Infants.

Monitoring whole body composition (fat mass and fat-free mass) in preterm infants may assist in optimizing nutrition and promoting growth and neurodevelopment in the neonatal intensive care unit. Currently, body composition assessment is not part of routine clinical evaluation of premature infants. Instead, weight and length are used to assess growth but are known to be poor predictors of adiposity shortly after birth. Although body composition methods, such as magnetic resonance imaging, stable-isotope dilution, and dual-energy x-ray absorptiometry, have been examined in infants, they involve exposure to radiation and are invasive, expensive, and/or unsuitable for repeated measurements in a medically fragile population. Several body composition methods with potential for clinical use have been explored in premature infants, including air displacement plethysmography, bioimpedance, skinfold measurements, and ultrasound. In this review, we examine each method and evaluate its feasibility for incorporation into clinical care. Although these methods show promise for use in premature infants, further research is needed before they can be recommended for routine body composition assessment in the clinical setting.

Motor Evoked Potentials as Potential Biomarkers of Early Atypical Corticospinal Tract Development in Infants with Perinatal Stroke.

Diagnosis of cerebral palsy (CP) after perinatal stroke is often delayed beyond infancy, a period of rapid neuromotor development with heightened potential for rehabilitation. This study sought to assess whether the presence or absence of motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) could be an early biomarker of atypical development within the first year of life. In 10 infants with perinatal stroke, motor outcome was assessed with a standardized movement assessment. Single-pulse TMS was utilized to assess presence of MEPs. Younger infants (3-6 months CA, n = 5, 4/5 (80%)) were more likely to present with an MEP from the more-affected hemisphere (MAH) compared to older infants (7-12 months CA, n = 5, 0/5, (0%)) (p = 0.048). Atypical movement was demonstrated in the majority of infants with an absent MEP from the MAH (5/6, 83%) compared to those with a present MEP (1/4, 25%) (p = 0.191). We found that age influences the ability to elicit an MEP from the MAH, and motor outcome may be related to MAH MEP absence. Assessment of MEPs in conjunction with current practice of neuroimaging and motor assessments could promote early detection and intervention in infants at risk of CP.

Neurodevelopmental outcomes following necrotizing enterocolitis.

Necrotizing enterocolitis (NEC), a gastrointestinal emergency predominantly affecting premature infants, is associated with increased risk for poor neurodevelopmental outcomes. NEC often strikes during a period of rapid and dynamic neurologic development when the brain is particularly vulnerable to insults and nutrient deficits. The pathogenesis of neurodevelopmental impairment following NEC is likely multifactorial, with both nutritional and non-nutritional factors at play. Follow-up testing that ensures early detection and intervention for impairments is crucial to optimize neurodevelopmental outcomes following NEC. A multifaceted approach to follow-up after NEC is necessary, with close monitoring of growth, serial developmental assessments, neurologic examinations, hearing and vision testing and neuroimaging. Further research is needed to understand the pathogenesis of neurodevelopmental impairment following NEC, to identify more targeted follow-up tests, and to discover interventions aimed at optimizing neurodevelopmental outcomes following NEC.