Orsola Amato

Evaluation of air-displacement plethysmography for body composition assessment in preterm infants

Background:Adiposity may contribute to the future risk of disease. The aim of this study was to evaluate the accuracy and reliability of an air-displacement plethysmography (ADP) system to estimate percentage fat mass (%FM) in preterm infants and to evaluate interdevice reliability in infants.Methods:A total of 70 preterm and 9 full-term infants were assessed. The accuracy of ADP measurements was assessed by determining reference %FM values using H218O dilution measurement.Results:Mean %FM by ADP was 5.67 ± 1.84 and mean %FM by H218O dilution was 5.99 ± 2.56. Regression analysis showed that %FM by ADP was associated with %FM by H218O dilution (R2 = 0.63, SE of estimate (SEE) = 1.65, P = 0.006). Bland–Altman analysis showed no bias (r = −0.48, P = 0.16) and 95% limits of agreement were −3.40 to 2.76 %FM. There was no difference in mean interdevice reliability %FM values (8.97 vs. 8.55 %FM) between ADP 1 and 2. Regression analysis indicated a low SEE (1.14% FM) and high R2 (0.91); 95% limits of agreement were −1.87 to 2.71 %FM. The regression line did not differ significantly from the line of identity.Conclusion:ADP is a noninvasive, reliable, and accurate technique to measure preterm infants’ body composition in both research and clinical settings.

Rapid recovery of fat mass in small for gestational age preterm infants after term

Background Preterm small for gestational age (SGA) infants may be at risk for increased adiposity, especially when experiencing rapid postnatal weight gain. Data on the dynamic features of body weight and fat mass (FM) gain that occurs early in life is scarce. We investigated the postnatal weight and FM gain during the first five months after term in a cohort of preterm infants. Methodology/Principal Findings Changes in growth parameters and FM were prospectively monitored in 195 infants with birth weight ≤1500 g. The infants were categorized as born adequate for gestational age (AGA) without growth retardation at term (GR−), born AGA with growth retardation at term (GR+), born SGA. Weight and FM were assessed by an air displacement plethysmography system. At five months, weight z-score was comparable between the AGA (GR+) and the AGA (GR−), whereas the SGA showed a significantly lower weight.The mean weight (g) differences (95% CI) between SGA and AGA (GR−) and between SGA and AGA (GR+) infants at 5 months were −613 (−1215; −12) and −573 (−1227; −79), respectively. At term, the AGA (GR+) and the SGA groups showed a significantly lower FM than the AGA (GR−) group. In the first three months, change in FM was comparable between the AGA (GR+) and the SGA groups and significantly higher than that of the AGA (GR−) group.The mean difference (95% CI) in FM change between SGA and AGA (GR−) and between AGA (GR+) and AGA (GR−) from term to 3 months were 38.6 (12; 65); and 37.7 (10; 65). At three months, the FM was similar in all groups. Conclusions Our data suggests that fetal growth pattern influences the potential to rapidly correct anthropometry whereas the restoration of fat stores takes place irrespective of birth weight. The metabolic consequences of these findings need to be elucidated.

Implementation of Nutritional Strategies Decreases Postnatal Growth Restriction in Preterm Infants

Background Prevention of postnatal growth restriction of very preterm infants still represents a challenge for neonatologists. As standard feeding regimens have proven to be inadequate. Improved feeding strategies are needed to promote growth. Aim of the present study was to evaluate whether a set of nutritional strategies could limit the postnatal growth restriction of a cohort of preterm infants. Methodology/Principal Findings We performed a prospective non randomized interventional cohort study. Growth and body composition were assessed in 102 very low birth weight infants after the introduction of a set of nutritional practice changes. 69 very low birth weight infants who had received nutrition according to the standard nutritional feeding strategy served as a historical control group. Weight was assessed daily, length and head circumference weekly. Body composition at term corrected age was assessed using an air displacement plethysmography system. The cumulative parenteral energy and protein intakes during the first 7 days of life were higher in the intervention group than in the historical group (530±81 vs 300±93 kcal/kg, p<0.001 and 21±2.9 vs 15±3.2 g/kg, p<0.01). During weaning from parenteral nutrition, the intervention group received higher parental/enteral energy and protein intakes than the historical control group (1380±58 vs 1090±70 kcal/kg; 52.6±7 vs 42.3±10 g/kg, p<0.01). Enteral energy (kcal/kg/d) and protein (g/kg/d) intakes in the intervention group were higher than in the historical group (130±11 vs 100±13; 3.5±0.5 vs 2.2±0.6, p<0.01). The negative changes in z score from birth to discharge for weight and head circumference were significantly lower in the intervention group as compared to the historical group. No difference in fat mass percentage between the intervention and the historical groups was found. Conclusions The optimization and the individualization of nutritional intervention promote postnatal growth of preterm infants without any effect on percentage of fat mass.

Neonatal Period: Body Composition Changes in Breast-Fed Full-Term Newborns

Background: Weight loss during initial days of life in healthy infants is known to consist of loss of both body solids and total body water. However, the nature of these body composition changes needs further investigation. Objective: To investigate the nature of changes in body composition that accompany weight loss during the first days of life in healthy term newborns. Methods: Body composition of healthy full-term newborns was assessed using air-displacement plethysmography. Cross-sectional (n = 262) and longitudinal samples (n = 28) were assessed during the first 4 and 5 days after delivery, respectively. Results: In the cross-sectional sample, mean body weight decreased significantly through day 4 (p < 0.001), mean fat mass (FM) and %FM decreased significantly (p = 0.005 and p = 0.031, respectively) by day 3. There was a significant decrease in mean fat-free mass on days 3 and 4 (p = 0.01 and p < 0.001, respectively). In the longitudinal sample, there was a significant decrease in mean body weight, FM and %FM (p < 0.001, p = 0.001, p = 0.013, respectively) by day 4. On day 5 there was a significant increase in mean body weight, FM and %FM (p < 0.001, p = 0.024, p = 0.036, respectively) when compared to day 4. There was no significant difference in mean FM and %FM values between day 1 and day 5. Conclusions: These results indicate that body composition changes are constituted by a reduction in both fat and fat free mass. However, a greater %FM is lost and consequently regained by day 5 when compared to fat-free mass.

Influence of protein and energy intakes on body composition of formula-fed preterm infants after term.

The aim of the present study was to evaluate changes in body composition in 48 preterm infants in relation to protein and energy intakes from term up to 3 months of corrected age, using air displacement plethysmography. Protein intake (grams per kilogram per day) was negatively associated with percentage of fat mass at 1 month of corrected age. The high-protein-intake group showed greater gain in lean body mass gain than did the low-protein-intake group. This finding suggests that during the first month of corrected age, high protein intake results in a significantly different weight gain composition.

Regional fat distribution in children born preterm evaluated at school age.

Children born preterm may have aberrant adiposity. At school age, we evaluated body fat and fat distribution in 45 former preterm infants (birth weight ≤1800 g and gestational age <34 weeks) and 40 children born at term using dual-energy x-ray absorptiometry. Children born preterm exhibited lower total body fat mass and total body fat mass index compared with children born at term. Fat mass indexes in the limbs but not the trunk were lower in children born preterm than in children born at term. In conclusion, children born preterm, evaluated at school age, may be at risk for altered regional adiposity.

Postnatal catch-up fat after late preterm birth.

Background:Late preterm birth accounts for 70% of preterm births. The aim of the study was to investigate the postnatal weight gain and weight gain composition changes in a cohort of late preterm infants.Methods:A total of 49 late preterm infants (mean birth weight 2,496 ± 330 g and gestational age 35.2 ± 0.7 wks) underwent growth and body composition assessment by an air displacement plethysmography system on the fifth day of life, at term, and at 1 and 3 mo of corrected age. The reference group was composed of 40 healthy, full-term, breast-fed infants.Results:The late preterm infants showed a Δ fat mass gain between birth and term-corrected age equal to 182%. As compared with full-term infants, at term and 1 mo of corrected age mean weight (3,396 ± 390 vs. 3,074 ± 409 g and 4,521 ± 398 vs. 4,235 ± 673 g, respectively) and percentage of fat mass (16.1 ± 4.6 vs. 8.9 ± 2.9 and 22.6 ± 4.2 vs. 17.4 ± 4.0, respectively) were significantly higher in late preterm infants, whereas no difference among groups was found at 3 mo.Conclusion:Rapid postnatal catch-up fat was found in these infants. Further studies are needed to investigate whether this short-term increase in fat mass may modulate the risk of chronic diseases or represent an adaptive mechanism to extrauterine life.

Quality Of Growth In Exclusively Breast-Fed Infants In the First Six Months Of Life: An Italian Study

Nutrition in early life, growth, and subsequent health over a lifetime are significantly interrelated. The aim of this study was to assess body composition changes in exclusively breast-fed infants from birth up to 6 mo of age. An observational, prospective, cohort study was conducted. Fifty-nine full-term, healthy, exclusively breast-fed infants underwent assessment of growth and body composition, using air-displacement plethysmograph (i.e. PEA POD) by Life Measurement, Inc. (Concord, CA). Body composition was assessed at birth, 2 wk, and 1, 2, 3, 4, 5, and 6 mo of age. Mean birth weight (g) and gestational age (wk) of the infants were 3170 ± 420 and 39.21 ± 1.29, respectively. Percentage of fat mass increased significantly over the first 4 mo (p < 0.001), both in boys and girls, with no differences detected between boys and girls at any time point. This article provides preliminary in-depth data on whole-body composition, in exclusively breast-fed infants during the first months of life. Further studies assessing larger sample sizes are desirable to develop reference body composition data.

Intervention for promoting breast milk use in neonatal intensive care unit: a pilot study

Abstract Objective: The health benefits provided by breast milk are significant in preterm infants. Despite recommendations, rates of breastfeeding in preterm infants are lower than in term infants. The aim of this study was to evaluate the efficacy of a multidisciplinary intervention in promoting any breastfeeding in preterm infants at discharge. Methods: A prospective non-randomized interventional cohort study was conducted. One hundred and twenty-two preterm infants constituted the historical group. A multidisciplinary intervention was performed including staff training and setting up and implementation of a written breastfeeding procedure. Results: One hundred and ten preterm infants were enrolled in the intervention group. The percentage of infants fed human milk at discharge was 69 and 62 in the intervention group and in the historical group, respectively. The percentage change from any breastfeeding at full enteral feeding attainment to formula feeding at discharge was lower in the intervention group than in the historical group (−9 versus −23). Belonging to the intervention group and having at least one stress factor during pregnancy were independently associated with any breast milk feeding at discharge. Conclusions: The multidisciplinary intervention performed appears to be effective in promoting any breastfeeding in preterm infants at discharge.

Effect of nutrition on growth and body composition in infants born preterm

The optimization of the nutritional management of preterm infants has gained importance due to the increased survival of these vulnerable infants. In fact, the achievement of an adequate growth has been associated with a favourable neurodevelopment outcome. Nevertheless, preterm infants still develop severe nutrient deficiencies during the first few weeks of life so that they are frequently growth restricted upon discharge. In addition, preterm infants have been found to show an increased and aberrant adiposity at term-corrected age. The development of strategies immediately after birth has been found to produce excellent results in terms of growth without having any detrimental effect on body composition at term-corrected age. Continuing to monitor growth and body composition changes in relation to different nutrition interventions is essential as growth pattern and body composition appear to have a long term effect on health outcomes.