Continuous growth reference from 24th week of gestation to 24 months by gender

<p>Abstract</p> <p>Background</p> <p>Growth charts and child growth assessment have become prime global instruments in child health practice over the 30 years. An updated, continuous growth standard that bridges size at birth values with postnatal growth values can improve child growth screening and monitoring.</p> <p>Methods</p> <p>This novel growth chart was constructed from two sources of information. Size at birth (weight, length and head circumference) reference values were updated based on information of normal deliveries (i.e. singleton live births without severe congenital malformation, with healthy mothers and born vaginally) from the Swedish Medical Birth Registry, 1990–1999 (n = 810393). Weight was evaluated using logarithmic transformation as for postnatal weight. Standard deviations were estimated from data within the empirical mean ± 1.0 SD for each gestational week and gender. These values were smoothed by empirical curve-fitting together with values from our recently published postnatal growth reference including 3650 longitudinally followed children from birth to final height <abbrgrp><abbr bid="B9">9</abbr></abbrgrp>. Timescale and weight axes were made logarithmic in order to magnify the early time part of the graph.</p> <p>Results</p> <p>This study presents the first continuous gender specific growth chart from birth irrespective of gestational age at birth until 2 years of age for weight, length and head circumference. Birth weight at 40 weeks of gestation increased approximately 100 gram and length increased only 1 mm compared with earlier Swedish reference from 1977–81. The curve is now less S-shaped as compared with earlier curves and compared with 4 curves from other countries and with more constant variation over the whole range.</p> <p>Conclusion</p> <p>Our values picture the unrestricted pattern of growth improving the detection of a deviating growth pattern, when the growth of an individual infant is plotted on the charts. Especially for very preterm infants age corrected growth can be more easily evaluated although it must be recognized that the early comparison is with what is estimated as normal growth in uterus. The reference values are useful in child health care systems for population screening, but also in research or in the clinic for evaluating various growth promoting interventions – either nutritional, surgical or therapeutic – that might affect a child in early life.</p

Low Birth Weight Is a Risk Factor for Severe Retinopathy of Prematurity Depending on Gestational Age

Objective: To evaluate the impact of low birth weight as a risk factor for retinopathy of prematurity (ROP) that will require treatment in correlation with gestational age at birth (GA). Study design In total, 2941 infants born <32 weeks GA were eligible from five cohorts of preterm infants previously collected for analysis in WINROP (Weight IGF-I Neonatal ROP) from the following locations: Sweden (EXPRESS) (n = 426), North America (n = 1772), Boston (n = 338), Lund (n = 52), and Gothenburg (n = 353). Data regarding GA at birth, birth weight (BW), gender, and need for ROP treatment were retrieved. Birth weight standard deviation scores (BWSDS) were calculated with Swedish as well as Canadian reference models. Small for gestational age (SGA) was defined as BWSDS less than −2.0 SDS using the Swedish reference and as BW below the 10th percentile using the Canadian reference charts. Results: Univariate analysis showed that low GA (p<0.001), low BW (p<0.001), male gender (p<0.05), low BWSDSCanada (p<0.001), and SGACanada (p<0.01) were risk factors for ROP that will require treatment. In multivariable logistic regression analysis, low GA (p<0.0001), male gender (p<0.01 and p<0.05), and an interaction term of BWSDS*GA group (p<0.001), regardless of reference chart, were risk factors. Low BWSDS was less important as a risk factor in infants born at GA <26 weeks compared with infants born at GA ≥26 weeks calculated with both reference charts (BWSDSSweden, OR = 0.80 vs 0.56; and BWSDSCanada, OR = 0.72 vs 0.41). Conclusions: Low BWSDS as a risk factor for vision-threatening ROP is dependent on the infant's degree of immaturity. In more mature infants (GA ≥26 weeks), low BWSDS becomes a major risk factor for developing ROP that will require treatment. These results persist even when calculating BW deficit with different well-established approaches

The first-year growth response to growth hormone treatment predicts the long-term prepubertal growth response in children

<p>Abstract</p> <p>Background</p> <p>Pretreatment auxological variables, such as birth size and parental heights, are important predictors of the growth response to GH treatment. For children with missing pretreatment data, published prediction models cannot be used.</p> <p>The objective was to construct and validate a prediction model for children with missing background data based on the observed first-year growth response to GH. The accuracy and reliability of the model should be comparable with our previously published prediction model relying on pretreatment data. The design used was mathematical curve fitting on observed growth response data from children treated with a GH dose of 33 μg/kg/d.</p> <p>Methods</p> <p>Growth response data from 162 prepubertal children born at term were used to construct the model; the group comprised of 19% girls, 80% GH-deficient and 23% born SGA. For validation, data from 205 other children fulfilling the same inclusion and treatment criteria as the model group were used. The model was also tested on data from children born prematurely, children from other continents and children receiving a GH dose of 67 μg/kg/d.</p> <p>Results</p> <p>The GH response curve was similar for all children, but with an individual amplitude. The curve SD score depends on an individual factor combining the effect of dose and growth, the 'Response Score', and time on treatment, making prediction possible when the first-year growth response is known. The prediction interval (± 2 SD_res) was ± 0.34 SDS for the second treatment year growth response, corresponding to ± 1.2 cm for a 3-year-old child and ± 1.8 cm for a 7-year-old child. For the 1–4-year prediction, the SD_reswas 0.13 SDS/year and for the 1–7-year prediction it was 0.57 SDS (i.e. < 0.1 SDS/year).</p> <p>Conclusion</p> <p>The model based on the observed first-year growth response on GH is valid worldwide for the prediction of up to 7 years of prepubertal growth in children with GHD/ISS, born AGA/SGA and born preterm/term, and can be used as an aid in medical decision making.</p

Models predicting the growth response to growth hormone treatment in short children independent of GH status, birth size and gestational age

<p>Abstract</p> <p>Background</p> <p>Mathematical models can be used to predict individual growth responses to growth hormone (GH) therapy. The aim of this study was to construct and validate high-precision models to predict the growth response to GH treatment of short children, independent of their GH status, birth size and gestational age. As the GH doses are included, these models can be used to individualize treatment.</p> <p>Methods</p> <p>Growth data from 415 short prepubertal children were used to construct models for predicting the growth response during the first years of GH therapy. The performance of the models was validated with data from a separate cohort of 112 children using the same inclusion criteria.</p> <p>Results</p> <p>Using only auxological data, the model had a standard error of the residuals (SD_res), of 0.23 SDS. The model was improved when endocrine data (GH_maxprofile, IGF-I and leptin) collected before starting GH treatment were included. Inclusion of these data resulted in a decrease of the SD_resto 0.15 SDS (corresponding to 1.1 cm in a 3-year-old child and 1.6 cm in a 7-year old). Validation of these models with a separate cohort, showed similar SD_resfor both types of models. Preterm children were not included in the Model group, but predictions for this group were within the expected range.</p> <p>Conclusion</p> <p>These prediction models can with high accuracy be used to identify short children who will benefit from GH treatment. They are clinically useful as they are constructed using data from short children with a broad range of GH secretory status, birth size and gestational age.</p

Low Postnatal Serum IGF-I levels is Associated with Bronchopulmonary Dysplasia (BPD).

Aim: To characterize postnatal changes in serum IGF-I in relation to development of bronchopulmonary dysplasia (BPD) in very preterm infants. Methods: Longitudinal study of 108 infants with mean (SD) gestational age 27.2 (2.2) weeks. Weekly serum samples of IGF-I were analyzed from birth until postmenstrual age 36 weeks. Multivariate models were developed to identify independent predictors of BPD. Results: Postnatal mean IGF-I levels at postnatal day 3 to 21 were lower in infants with BPD compared to infants with no BPD (16 vs. 26 ug/L, p<0.001). Longitudinal postnatal change in IGF-I levels (IGF-I regression coefficient (β), postnatal days 3 to 21, was lower in infants with BPD compared to infants with no BPD (0.28 vs. 0.97, p=0.002) and mean IGF-I during postmenstrual age 30-33 weeks was lower in infants with BPD as compared to infants without BPD (22 vs. 29 ug/L, p<0.001). In a binomial multiple regression model lower gestational age, male gender and lower mean serum IGF-I levels during postnatal day 3-21 were the most predictive risk factors associated with BPD (r(2) =0.634, p<0.001). Conclusion: Lower IGF-I concentrations during the first weeks after very preterm birth are associated with later development of BPD. © 2012 The Author(s)/Acta Paediatrica © 2012 Foundation Acta Paediatrica

Maternal and neonatal factors associated with poor early weight gain and later retinopathy of prematurity

Aim: To identify factors associated with poor early weight gain as reflected in an alarm system, WINROP, and risk of later proliferative retinopathy of prematurity (ROP) in infants with gestational age (GA) < 28 weeks

Fresh-frozen Plasma as a Source of Exogenous Insulin-like Growth Factor I in the Extremely Preterm Infant.

Context: Preterm birth is followed by a decrease in circulatory levels of IGF-I and IGF binding protein-3 (IGFBP-3), proteins with important neurogenic and angiogenic properties. Objective: To evaluate effects of intravenous administration of fresh frozen plasma (FFP) from adult donors on circulatory levels of IGF-I and IGFBP-3 in extremely preterm infants. Design, setting and patients: A prospective cohort study performed in twenty extremely preterm infants (mean (SD) gestational age 25.3 (1.3) weeks) with clinical requirement of FFP during the first postnatal week. Sampling was performed before initiation of transfusion, directly after and at 6, 12, 24 and 48h after completed FFP transfusion. Main outcome measures: Concentrations of IGF-I and IGFBP-3 before and after transfusion of FFP. Results: FFP with a mean (SD) volume of 11 (3.1) ml/kg, was administered at a postnatal age of median (range) 2 (1-7) days. Mean (SD) IGF-I and IGFBP-3 concentrations in administered FFP were 130 (39) and 2840 (615) microg/L, respectively. Immediately after FFP transfusion, mean (SD) concentrations of IGF-I increased by 133% from 11 (6.4) to 25 (9.3) microg/L, p<0.001 and IGFBP-3 by 61% from 815 (451) to 1311 (508) microg/L, p<0.001. Concentrations of IGF-I and IGFBP-3 remained higher at 6 h, p<0.001, p=0.009 and at 12 h, p=0.017, p=0.018, respectively, as compared to concentrations before FFP transfusion. Typical half-life of administrated IGF-I was 3.4 h for a 1 kg infant. Conclusion: Transfusion of FFP to extremely preterm infants during the first postnatal week elevates levels of IGF-I and IGFBP-3