An examination of the association between infant non-nutritive suck and developmental outcomes at 12 months.

OBJECTIVE: To determine the association between infant non-nutritive suck (NNS) dynamics at 3 months and developmental outcomes at 12 months of age in full-term infants. We hypothesized that infants with more mature NNS at 3 months, as evidence by shorter burst duration, fewer cycles per burst, cycles per minute, higher amplitude, and more bursts, would have higher (better) scores on the developmental outcomes at 12 months. METHODS: This was a prospective study that utilized objective and self-report measures. A five-minute NNS sample was collected from 67 infants (54% male) at 3 months of age (average age 2.99 (0.27) months). At 12 months (average age 11.91 (0.26) months), the Development Profile-3 was administered through caregiver interview. RESULTS: Infant NNS burst duration, cycles per burst, and cycles per minute were significantly negatively associated with the Development Profile-3 cognitive domain and general scores at 12 months. This is consistent with our hypothesis that infants who have more efficient NNS (fewer bursts and cycles) at 3 months would have higher (better) scores on the Development Profile-3 at 12 months. CONCLUSIONS: Findings from this work complement emerging research linking infant NNS with subsequent neurodevelopmental outcomes. This is the first time that these associations have been examined using a quantitative and physiologic-based measure of NNS. These results seem to indicate that specific NNS metrics, which demonstrate maturation of this complex skill, may be useful predictors of neurodevelopment later in life.

Infant Bottle-Feeding: A Prospective Study of Infant Physiology and Parental Report Metrics.

The aim of this study was to examine associations between parent reports of bottle-feeding behaviors and infant non-nutritive suck (NNS) on a pacifier as well as oral feeding skills during bottle-feeding. A prospective study was conducted. Full-term infants with no prior diagnosed feeding disorders were recruited at 3-months. Parents reported their infant's bottle-feeding behaviors using the Neonatal Eating Assessment Tool-Bottle-Feeding (NeoEAT-Bottle-Feeding), consisting of five domains: Infant Regulation, Energy and Physiologic Stability, Gastrointestinal Tract Function, Sensory Responsiveness, and Compelling Symptoms of Problematic Feeding. Infant NNS was measured using a custom pacifier, pressure transducer device, which yields the following NNS variables: duration (sec), frequency (Hz), amplitude (cmH20), cycles per burst, cycle amount, and burst amount. The Oral Feeding Skills (OFS) scale was used to measure the initial volume, transfer volume, proficiency, and rate of milk transfer during bottle feeding. Fifty-two infants (58% male) with reported prior bottle experience completed this study. NeoEAT-Bottle-Feeding Total score was significantly positively associated with NNS burst duration and NNS cycles per burst. The NeoEAT-Bottle-Feeding Energy and Physiologic Stability domain was significantly positively correlated with NNS cycles per burst. NeoEAT-Bottle-Feeding Gastrointestinal Tract Function domain score was significantly positively correlated with NNS duration, amplitude, and cycles per burst. There were no significant associations between NeoEAT-Bottle-Feeding domains and the OFS scale. The findings demonstrate that parent reports of problematic feeding at 3 months of age are associated with aspects of infant NNS physiology and not with oral feeding metrics during bottle-feeding. Parent reports of bottle-feeding behaviors, particularly pertaining to gastrointestinal issues, were associated with aspects of infant NNS. These data together will allow for a more nuanced understanding of infant feeding and will be beneficial in determining if infants have a feeding delay.

Developmental regulation of GABAergic gene expression in forebrain cholinergic neurons.

Acetylcholine and GABA are often co-released, including from VIP-expressing neurons of the cortex, cortically-projecting neurons of the globus pallidus externus and basal forebrain, and hippocampal-projecting neurons of the medial septum. The co-release of the functionally antagonistic neurotransmitters GABA and acetylcholine (ACh) greatly expands the possible functional effects of cholinergic neurons and provides an additional exogenous source of inhibition to the cortex. Transgene expression suggests that nearly all forebrain cholinergic neurons in mice at some point in development express Slc32a1, which encodes the vesicular GABA transporter (VGAT). To determine the degree of co-expression of GABA and Ach handling proteins, we measured expression in adult mice of Slc32a1, Gad1 and Gad2 (which encode GAD67 and GAD65, respectively, the GABA synthetic enzymes) in cholinergic neurons using fluorescent in situ hybridization. We found that only a subset of cholinergic neurons express the necessary machinery for GABA release at a single time in adult mice. This suggests that GABA co-release from cholinergic neurons is dynamic and potentially developmentally regulated. By measuring expression of Slc32a1, Gad1, Gad2, and Chat in the basal forebrain and medial septum in mice from post-natal day 0 to 28, we noted abundant yet variable expressions of GABAergic markers across early development, which are subsequently downregulated in adulthood. This is in contrast with the forebrain-projecting pedunculopontine nucleus, which showed no evidence of co-expression of GABAergic genes. These results suggest that expression of GABA signaling machinery in the cortically-projecting cholinergic system peaks during early development before settling at a non-zero level that is maintained through adulthood.

Examining the association between prenatal maternal stress and infant non-nutritive suck.

BACKGROUND: This study examined the relationship between prenatal maternal stress (PREMS) and non-nutritive suck (NNS) and tested its robustness across 2 demographically diverse populations. METHODS: The study involved 2 prospective birth cohorts participating in the national Environmental influences on Child Health Outcomes (ECHO) Program: Illinois Kids Development Study (IKIDS) and ECHO Puerto Rico (ECHO-PROTECT). PREMS was measured during late pregnancy via the 10-item Perceived Stress Scale (PSS-10). NNS was sampled from 1- to 8-week-olds using a custom pacifier for ~5 min. RESULTS: Overall, 237 mother-infant dyads completed this study. Despite several significant differences, including race/ethnicity, income, education, and PREMS levels, significant PREMS-NNS associations were found in the 2 cohorts. In adjusted linear regression models, higher PREMS, measured through PSS-10 total scores, related to fewer but longer NNS bursts per minute. CONCLUSIONS: A significant association was observed between PREMS and NNS across two diverse cohorts. This finding is important as it may enable the earlier detection of exposure-related deficits and, as a result, earlier intervention, which potentially can optimize outcomes. More research is needed to understand how NNS affects children's neurofunction and development. IMPACT: In this double-cohort study, we found that higher maternal perceived stress assessed in late pregnancy was significantly associated with fewer but longer sucking bursts in 1- to 8-week-old infants. This is the first study investigating the association between prenatal maternal stress (PREMS) and infant non-nutritive suck (NNS), an early indicator of central nervous system integrity. Non-nutritive suck is a potential marker of increased prenatal stress in diverse populations. Non-nutritive suck can potentially serve as an early indicator of exposure-related neuropsychological deficits allowing for earlier interventions and thus better prognoses.

The home environment and its relation to bottle feeding outcomes in the first year of life.

BACKGROUND: The home environment and caregiver interactions have an impact on infant development. However, there is a paucity of research surrounding the home environment and its relation to early feeding outcomes within the first year of life. Therefore, the aim of this study was to examine the relationship between the home environment and infant bottle feeding outcomes at 3 and 12 months of age. METHODS: Seventy-two full-term infants completed this study at 3 months of age and fifty-five infants completed the study at 12 months. Data in the current study were collected from a larger, ongoing study completed in the infant's home at 3 and 12 months of age. The Infant-Toddler Home Observation for Measurement of Environment Inventory (IT-HOME) was utilized to assess the infant's home environment. The Oral Feeding Skills (OFS) scale was completed while the infant was observed during a bottle feed. Caregivers completed a questionnaire about their infant's feeding abilities via the Neonatal Eating Assessment Tool (Neo-EAT) at 3 months and Pediatric Eating Assessment Tool (Pedi-EAT) at 12 months. RESULTS: At 3 months of age, the IT-HOME Involvement subscale was associated with an increase in the amount of milk provided in the infant's bottle. There were no significant associations between the IT-HOME and caregiver report of feeding at 3 months of age. At 12 months of age, the IT-HOME Acceptance subscale was associated with an increase in oral transfer rate and the IT-HOME Variety subscale was associated with a decrease in oral transfer rate. Additionally, the IT-HOME Organization subscale was associated with caregiver report of feeding on the following Pedi-EAT scales: Mealtime Behaviors, Selective Restrictive Eating, and Oral Processing at 12 months. CONCLUSIONS: These findings reveal that the home environment is significantly related to different infant bottle feeding outcomes over the first year of life. At 3 months, IT-HOME Involvement was associated with the amount of milk offered in the bottle, whereas at 12 months of age, subscales of the IT-HOME were associated with oral feeding transfer rate and caregiver report of feeding. Clinically, these findings point to the importance of considering the infant's bottle feeding skills in conjunction with certain aspect within the infant's environment. Additional research is needed to further explore these relationships in greater detail, with a larger sample size and across patient populations.

Association between Quality of Maternal Prenatal Food Source and Preparation and Breastfeeding Duration in the Environmental Influences on Child Health Outcome (ECHO) Program.

This study examined the relationship between maternal food source and preparation during pregnancy and the duration of breastfeeding among 751 mother-child dyads in the United States. The data collected from the Environmental influences on Child Health Outcomes (ECHO) Program included twelve cohorts of mothers (age ≥ 18) who delivered infant(s). Three categories of maternal food source and preparation including, High, Moderate, or Low Food Source Quality were derived from the mother report. The mean duration of breastfeeding differed strongly across the three categories. The High Food Source Quality group breastfed an average of 41 weeks, while shorter durations were observed for the Moderate (26 weeks) and Low (16 weeks) Food Source Quality groups. Cox proportional hazards models were used to estimate the relative hazard of time to breastfeeding cessation for each participant characteristic. The full model adjusted for clustering/cohort effect for all participant characteristics, while the final model adjusted for the subset of characteristics identified from variable reduction modeling. The hazard of breastfeeding cessation for those in the High Food Source Quality group was 24% less than the Moderate group (RH = 0.76; 95% CI, 0.63-0.92). Pregnant women in the High Food Source Quality group breastfed longer than the Moderate and Low groups. We encourage more detailed studies in the future to examine this relationship longitudinally.

The home environment and its relation to vocalizations in the first year of life.

Background: Prior data has shown that the home environment impacts child development; however, there remains a paucity of research on how the home environment relates to child and adult words. Therefore, the aim of this prospective and quantitative study was to examine the relationship between the home environment and the quantity of vocalizations or words, and conversational turns produced by infants and parents at 3 and 12 months of age. Methods: Seventy-two (56% male) full-term infants were assessed at 3 and 12 months of age. The home environment was assessed in person via interview and observation of the child's home using the Infant-Toddler Home Observation for Measurement of the Environment (IT-HOME) Inventory subscales. Vocalizations were measured using the Language Environment Analysis (LENA) device, which measures the adult word count, child vocalization count and conversational turn count. These measures were then averaged for the most voluble, or vocal hour, in the recording period. Results: At 3 months, IT-HOME Learning Materials scores were significantly associated with a decrease in adult words. We found a statistically significant difference in LENA outcomes between 3 and 12 months when stratified by sex. Specifically, male infants had significantly fewer vocalizations at 12 months when compared to 3 months, whereas females had more vocalizations. There was also a statistically significant difference in IT-HOME Learning Materials, Organization, Responsivity, and Total scores when comparing 3- and 12-month time points. Conclusions: These findings reveal that the home environment changes significantly over the first year of life. At 3 months, Learning Materials in the home were related to adult words, while between 3 and 12 months, several aspects of the home significantly changed. Male children had reduced vocalizations between 3 and 12 months; whereas, female children had increased vocalizations during the same time points. Future research should focus on examining these outcomes with multiple measures, time points, and patient populations.

Birth Order Effects on Breastfeeding Self-Efficacy, Parent Report of Problematic Feeding and Infant Feeding Abilities.

The goal of this prospective study was to identify effects of birth order on breastfeeding self-efficacy, parental-report of infant feeding behaviors, infant non-nutritive sucking and oral feeding skills in full-term infants at 3-months. Mothers were separated into primipara and multipara groups, and infants were grouped into siblings and no siblings groups. Parents completed the Breastfeeding Self-Efficacy Scale-Short Form, and Neonatal Eating Assessment Tool-Breastfeeding and Bottle-feeding scales. Non-nutritive sucking was assessed using a custom research pacifier and researchers completed the Oral Feeding Skills scale to assess feeding performance. Fifty-six mother-infant dyads (55% male) were included. Primipara mothers reported significantly lower breastfeeding self-efficacy and more feeding problems across breast and bottle-feeds on the Neonatal Eating Assessment Tool. There were no significant differences in non-nutritive sucking or oral feeding skills between infant groups. First-time mothers require more infant feeding support as they exhibited lower breastfeeding self-efficacy and reported more problematic feeding behaviors.

Correlation between maternal eating disorder and early infant feeding regulation: a cross -sectional study.

BACKGROUND: The post-partum period is a vulnerable time for mothers in terms of eating disorder symptoms and is critical for the establishment of feeding patterns in infants. This study aimed to investigate the relationships between maternal eating disorder symptoms and objective indices of feeding regulation at 3 months, as well as perceived breastfeeding self-efficacy. METHODS: A sample of n = 73 full-term mother-child dyads (44% female) participated in the study. Mothers self-reported eating disorder symptoms and breastfeeding self-efficacy and objective indices of infant feeding regulation were obtained in the home. RESULTS: Findings revealed the existence of relationships between higher maternal eating disorder symptoms, and objective indices of infant feeding regulation with substantial gender differences in the patterns emerging. Among mother-daughter dyads, maternal weight and shape concerns were associated with higher infant transfer volume and rate during bottle feeding. In contrast, among mother-son dyads, higher maternal eating disorder symptoms, including weight, shape, and eating concern, were associated with lower infant transfer volume and rate as well as lower levels of proficiency while taking their bottle. CONCLUSION: Relationships emerged between higher maternal eating disorder symptoms and feeding regulation with substantial gender differences in these patterns. Additional research clarifying the underlying mechanisms of these associations is warranted and further efforts should be directed towards supporting mothers during the postpartum period.

Non-nutritive suck and airborne metal exposures among Puerto Rican infants.

Air pollution has been shown to impact multiple measures of neurodevelopment in young children. Its effects on particularly vulnerable populations, such as ethnic minorities, however, is less studied. To address this gap in the literature, we assess the associations between infant non-nutritive suck (NNS), an early indicator of central nervous system integrity, and air pollution exposures in Puerto Rico. Among infants aged 0-3 months enrolled in the Center for Research on Early Childhood Exposure and Development (CRECE) cohort from 2017 to 2019, we examined associations between exposure to fine particulate matter (PM2.5) and its components on infant NNS in Puerto Rico. NNS was assessed using a pacifier attached to a pressure transducer, allowing for real-time visualization of NNS amplitude, frequency, duration, cycles/burst, cycles/min and bursts/min. These data were linked to 9-month average prenatal concentrations of PM2.5 and components, measured at three community monitoring sites. We used linear regression to examine the PM2.5-NNS association in single pollutant models, controlling for infant sex, maternal age, gestational age, and season of birth in base and additionally for household smoke exposure, age at testing, and NNS duration in full models. Among 198 infants, the average NNS amplitude and burst duration was 17.1 cmH2O and 6.1 s, respectively. Decreased NNS amplitude was consistently and significantly associated with 9-month average exposure to sulfur (-1.026 ± 0.507), zinc (-1.091 ± 0.503), copper (-1.096 ± 0.535) vanadium (-1.157 ± 0.537), and nickel (-1.530 ± 0.501). Decrements in NNS frequency were associated with sulfur exposure (0.036 ± 0.018), but not other examined PM components. Our findings provide new evidence that prenatal maternal exposure to specific PM components are associated with impaired neurodevelopment in Puerto Rican infants soon after birth.

Associations of gestational phthalate exposure and non-nutritive suck among infants from the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) birth cohort study.

BACKGROUND: Infant non-nutritive suck (NNS), or sucking on a pacifier with no nutrients being delivered, has been used as in index of brain function and has been linked to subsequent neurodevelopment. Yet, no data are available connecting NNS to environmental exposures in utero. The goal of this study was to examine the relationship between gestational exposure to phthalates (a group of chemicals found in personal care products, PVC plastics, and other products) and NNS among infants in a birth cohort study in Puerto Rico. METHODS: Urinary phthalate metabolite levels were measured in women at up to three time points in pregnancy as a measure of in utero exposure to the child. We calculated the geometric mean of each metabolite for each woman as a measure of exposure across gestation. Infants had their NNS sampled using our custom research pacifier between 4-6 (± 2 weeks) weeks of age, yielding the following NNS dependent measures: cycles/burst, frequency, amplitude, bursts/min, and cycles/min. RESULTS: Two hundred and eight mother-infant dyads completed this study We used multiple linear regression to assess associations between individual phthalate metabolites and NNS measurements, adjusting for infant sex, birthweight, and urinary specific gravity. An interquartile range (IQR) increase in mono carboxyisononyl phthalate across pregnancy was associated with 3.5% (95%CI: -6.2, -0.8%) lower NNS frequency and 8.9% (0.6, 17.3%) higher NNS amplitude. Similarly, an IQR increase in mono-2-ethylhexyl phthalate was also associated with 3.4% (-6.5, -0.2%) lower NNS frequency, while an IQR increase in di-2-ethylhexyl terephthalate metabolites was associated with 11.2% (2.9, 19.5%) higher NNS amplitude. Gestational exposure to phthalates may alter NNS amplitude and frequency in full-term infants. These findings indicate that the infants may be increasing their NNS amplitude to compensate for their slower NNS frequency. These preliminary findings could have important clinical implications for earlier detection of exposure-related deficits in neurofunction as well as implications for subsequent neurodevelopment and related interventions.

Changes in non-nutritive suck between 3 and 12 months.

BACKGROUND: Non-nutritive suck (NNS) is one piece of the complex oral feeding process, yet there is paucity on how it develops throughout the first year of life. AIMS: To determine changes in infant NNS between 3 and 12 months of age. STUDY DESIGN: Twenty-six full-term infants (65% male) completed this study. All infants were offered our custom research pacifier to attain a quantitative analysis of their suck pattern. Based on quantitative analyses of NNS cycle count, the best 2 min of infants' suck were selected and analyzed. OUTCOME MEASURES: NNS duration, amplitude, cycles/burst, frequency, cycles, and bursts. RESULTS: NNS duration, bursts, cycles/burst and cycles significantly decreased from 3 to 12 months, yet amplitude significantly increased over the same time period. Additionally, no significant differences were evident for NNS frequency. Three-month-old infants produced a median of 4.50 suck bursts per minute that contained 9.60 cycles/burst, resulting in a burst duration of 4.74 s. The median NNS frequency was 2.09 Hz, with an average amplitude of 14.05 cmH20. Twelve-month-old infants produced a median of 2.50 suck bursts that contained 3.75 cycles/burst, resulting in a burst duration of 1.67 s. The median NNS frequency was 2.11 Hz with an amplitude of 19.75 cmH20. CONCLUSION: Full-term infants significantly change their NNS duration, amplitude, burst number, cycles/burst and cycle number with no significant changes present in NNS frequency between 3 and 12 months. Knowledge of NNS emergence and maturation during the first year of life is imperative for proper NNS assessment so that healthcare professionals can identify delays.