Growth Assessment in Preterm Children from Birth to Preschool Age

Infant growth by INTERGROWTH-21st and Fenton Growth Charts: Predicting 1-year anthropometry in South African preterm infants

Post-natal growth influences short- and long-term preterm infant outcomes. Different growth charts, such as the Fenton Growth Chart (FGC) and INTERGROWTH-21st Preterm Post-natal Growth Standards (IG-PPGS), describe different growth curves and targets. This study compares FGC- and IG-PPGS-derived weight-for-postmenstrual age z-score (WZ) up to 50 weeks postmenstrual age (PMA50) for predicting 1-year anthropometry in 321 South African preterm infants. The change in WZ from birth to PMA50 (ΔWZ, calculated using FGC and IG-PPGS) was correlated to age-corrected 1-year anthropometric z-scores for weight-for-age (WAZ), length-for-age (LAZ), weight-for-length (WLZ) and BMI-for-age (BMIZ), and categorically compared with rates of underweight (WAZ < -2), stunting (LAZ < -2), wasting (WLZ < -2) and overweight (BMIZ > + 2). Multivariable analyses explored the effects of other early-life exposures on malnutrition risk. At PMA50, mean WZ was significantly higher on IG-PPGS (-0.56 ± 1.52) than FGC (-0.90 ± 1.52; p < 0.001), but ΔWZ was similar (IG-PPGS -0.26 ± 1.23, FGC -0.11 ± 1.14; p = 0.153). Statistically significant ΔWZ differences emerged among small-for-gestational age infants (FGC -0.38 ± 1.22 vs. IG-PPGS -0.01 ± 1.30; p < 0.001) and appropriate-for-gestational age infants (FGC + 0.02 ± 1.08, IG-PPGS -0.39 ± 1.18; p < 0.001). Correlation coefficients of ΔWZ with WAZ, LAZ, WLZ and BMIZ were low (r < 0.45), though higher for FGC than IG-PPGS. Compared with IG-PPGS, ΔWZ < -1 on FGC predicted larger percentages of underweight (42% vs. 36%) and wasting (43% vs. 39%) and equal percentages of stunting (33%), while ΔWZ > + 1 predicted larger percentages overweight (57% vs. 38%). Both charts performed similarly in multivariable analysis. Differences between FGC and IG-PPGS are less apparent when considering ΔWZ, highlighting the importance of assessing growth as change over time, irrespective of growth chart.

Association of Neonatal Antibiotic Exposure with Long-Term Growth Trajectory Faltering in Preterm-Birth Children

INTRODUCTION

Preterm neonates often receive a variety of duration of antibiotic exposure during admission. The aim of the study was to evaluate whether neonatal antibiotic exposure is relevant with longitudinal growth problems in preterm-birth children.

METHODS

This prospective study enrolled 481 infants who were born <32 weeks of gestation, discharged, and longitudinally followed from corrected age (CA) 6-60 months. After excluding 153 infants with blood culture-confirmed bacteremia, necrotizing enterocolitis, severe cerebral palsy, intestinal ostomy, and congenital anomaly, 328 infants were included for analysis. Covariates included perinatal demographics, neonatal morbidities, extrauterine growth restriction, and antibiotic exposure accumulated by term equivalent age. The primary outcome was the anthropometric trajectories in z-score of bodyweight (zBW), body height (zBH), and body mass index (zBMI) from CA 6-60 months.

RESULTS

Antibiotic exposure duration was significantly negatively associated with zBW and zBH at CA 6, 12, and 60 months, and zBMI at CA 60 months. Multivariate generalized estimating equation analyses showed antibiotic exposure duration had significantly faltering z-score increment from CA 6 to 60 months in zBW and zBH (adjusted mean [95% CI]; ΔzBW: -0.021 [-0.041 to -0.001], p = 0.042; ΔzBH: -0.019 [-0.035 to -0.002], p = 0.027) after adjustment. Children with neonatal antibiotic exposure duration >15 days were significantly lower in the mean anthropometric zBW, zBH, and zBMI at CA 6, 12, 24, and 60 months compared with children with neonatal antibiotic exposure ≤15 days (all p < 0.01).

CONCLUSIONS

Growth increments were negatively associated with antibiotic exposure duration in preterm neonates implicating that antibiotic stewardship and growth follow-up for preterm neonates are thus warranted.

Comparison of different growth curves in the assessment of extrauterine growth restriction in very low birth weight preterm infants

BACKGROUND

Preterm infants are at risk of extrauterine growth restriction (EUGR) and associated complications in the long term. Growth curves are important in assessing postnatal growth in these infants. The aim of this study was to determine the prevalence of EUGR in preterm infants and the factors associated with EUGR using two different growth curves.

METHODS

We retrospectively evaluated 596 preterm infants with birth weight ≤1500 g. Small for gestational age (SGA) was defined as birth weight <10th percentile for gestational age. EUGR was defined as discharge weight z score <-2. All z scores were determined using both the Fenton 2013 and Intergrowth-21st (IG-21) growth curves.

RESULTS

The infants' median gestational age was 28 weeks (27-29) and median birth weight was 1080 g (900-1243). The prevalence of SGA was 9.2% with IG-21 curves and 5% with Fenton curves (p < 0.001). The median discharge weight was 2060 g (1860-2363). The prevalence of EUGR was significantly higher with the Fenton curves than with the IG-21 curves (38% vs. 31.7%, p < 0.001). The mean discharge weight z score was -1.82±1.29 with Fenton and -1.44±1.49 with IG-21 curves. In multivariate analysis, significant risk factors for EUGR according to the Fenton curves were SGA (odds ratio [OR]: 19.15, 95% confidence interval [CI]: 4.4-82.59), respiratory distress syndrome (RDS) (OR 1.64, 95% CI 1.12-2.4), late neonatal sepsis (LNS) (OR: 2.27, 95% CI: 1.5-3.44), and >16 days to full enteral feeding (OR: 1.8, 95% CI: 1.22-2.68). Similarly, independent risk factors for EUGR according to the IG-21 curve were SGA (OR: 16.3, 95% CI: 7.23-36.9), RDS (OR: 1.81, 95% CI: 1.16-2.83), LNS (OR: 2.29, 95% CI: 1.43-3.68), and >16 days to full enteral feeding (OR: 2.11, 95% CI: 1.38-3.23).

CONCLUSION

The growth curves used for diagnosis may lead to differences in EUGR rates in intensive care units and the factors identified as associated with EUGR. At-risk infants should be evaluated for EUGR and their weight and nutritional support should be monitored carefully. Comparisons of long-term outcomes are needed to assess the suitability of growth curves used for EUGR follow-up.

Nonlinear relationship between early postnatal weight gain velocity and neurodevelopmental outcomes in very-low birth weight preterm infants: A secondary analysis based on a published prospective cohort study

BACKGROUND

Extrauterine growth restriction among the very-low birth weight preterm infants (VLBWPIs) is associated with poorer cognitive development outcome, while the rapid weight gain in infancy increases the long-term risk of obesity and noncommunicable disease among VLBWPIs. However, the results of research on the association between early postnatal growth velocity and neurodevelopmental outcomes in VLBWPIs are still limited and controversial.

OBJECTIVE

We aimed to explore the association between the growth velocity in early postnatal and neurodevelopmental impairment (NDI) among VLBWPIs.

METHODS

This study was a secondary analysis of a previously published prospective cohort. It was based on data on 1,791 premature infants with a birth weight of less than 1500 g, registered in the database of the Premature Baby Foundation of Taiwan between 2007 and 2011. A binary logistic regression model was used to evaluate the association between the weight gain velocity in different periods [from birth to 6 months corrected age (CA), 6 to 12 months CA, and 12 to 24 months CA] and NDI, respectively. The generalized additive model and the smooth curve fitting (penalized spline method) were used to address nonlinearity, and a two-piece-wise binary logistic regression model was added to explain the nonlinearity further.

RESULTS

Nonlinearities were observed between NDI and the weight gain velocity from birth to 6 months CA [inflection point 20.36, <inflection point: odds ratio (OR) = 0.75, 95% confidence interval (CI) 0.67-0.84, >inflection point: OR = 1.01, 95% CI 0.97-1.05], 6-12 months CA [inflection point 9.44, <inflection point: OR = 0.89, 95% CI 0.84-0.94, >inflection point: OR = 1.05, 95% CI 1.05-(1.00, 1.11)], and 12-24 months CA [inflection point 16.00, <inflection point: OR = 0.93, 95% CI 0.88-0.98, >inflection point: OR = 1.75, 95% CI 1.05-(0.96, 3.08)].

CONCLUSION

The neurodevelopmental benefits from a rapid weight gain velocity from birth to 24 months CA might be limited once the growth pace reaches an optimum level. It would help find a pattern of growth that facilitates optimal neurodevelopment, yet minimizes negative health consequences associated with overnutrition further.