El peso para la longitud en pretérminos tardíos evaluados con impedancia bioélectrica se asocia a variables antropométricas / Weight for length in late preterm infants assessed with bioelectrical impedance is positively associated with anthropometric variables

Introducción: La masa grasa es mayor en lactantes pretérmino tardíos que en lactantes nacidos a término al mes de vida y esto podría ser un factor de riesgo adicional para el síndrome metabólico en la vida adulta. Objetivos: Para evaluar la composición corporal (CC) en prematuros tardíos utilizamos el análisis de impedancia bioeléctrica y buscamos determinar qué parámetro antropométrico está asociado con la CC. Nuestra hipótesis es que el peso para la longitud está asociado con el índice de masa grasa (IMG) normalizado por longitud al año de vida. Materiales y métodos: Realizamos un estudio de cohortes prospectivo con 2 grupos: prematuros tardíos y nacidos a término. Los datos de CC se midieron mediante análisis de impedancia bioeléctrica. Se calcularon la masa grasa, el IMG, la masa libre de grasa y el índice de MLG normalizado por talla a los 1, 6 y 12 meses de vida. Luego determinamos la asociación del IMG con los parámetros antropométricos mediante un análisis de regresión lineal múltiple. Resultados: Incluimos 97 prematuros tardíos y 47 nacidos a término, aunque la evaluación de CC se realizó en 66 y 33 a los 12 meses de vida. Al mes, el contenido de masa libre de grasa fue mayor en los recién nacidos prematuros tardíos (4013 frente a 3524g); a los 6 meses, tuvieron una mayor velocidad de incremento de peso (5480g versus 4604g) y a los 12 meses de vida, el contenido de masa libre de grasa y el índice de MLG de los recién nacidos prematuros tardíos fue menor que el de los recién nacidos a término (7232 versus 7813g; 12,55 versus 13.26). Según el análisis de regresión multivariable, la puntuación z del peso para la talla a los 12 meses se asoció positivamente con el IMG a los 12 meses en todos los lactantes. (AU)

Introduction: The fat mass is greater in late preterm than full term infants at 1 month post birth, which may be an additional risk factor for metabolic syndrome in adulthood. Objectives: To evaluate body composition (BC) in late preterm infants using bioelectrical impedance analysis to determine which anthropometric parameters are associated with BC. Our hypothesis was that weight-for-length is associated with the length-normalized fat mass index (FMI) at 1 year of life. Materials and methods: We carried out a prospective cohort study in 2 groups: late preterm infants and full term infants. We obtained BC data by bioelectrical impedance analysis. We calculated the fat mass, FMI, fat-free mass (FFM) and length-normalized FFM index at 1, 6 and 12 months of life. After, we assessed the association of the FMI with anthropometric parameters using multiple linear regression analysis. Results: The study included 97 late preterm and 47 full term infants, although at 12 months of life, the BC assessment was performed on 66 and 33 infants, respectively. Late preterm infants, compared to full term infants, had a higher FFM at 1 month (4013g vs. 3524g), a higher weight velocity at 6 months (5480g vs. 4604g) and a lower FFM (7232g vs. 7813g) and FFM index (12.55 vs. 13.26) at 12 months of life. The multivariate regression analysis showed that the weight-for-length z-core at 12 months was positively associated with the FMI at 12 months in all infants. (AU)

The weight for length in late preterm infants assessed with bioelectrical impedance is positively associated with anthropometric variables.

INTRODUCTION: The fat mass (FM) is greater in late preterm than full term infants at 1 month post birth, which may be an additional risk factor for metabolic syndrome in adulthood. OBJETIVES: To evaluate body composition (BC) in late preterm infants using bioelectrical impedance analysis (BIA) to determine which anthropometric parameters are associated with BC. Our hypothesis was that weight-for-length is associated with the length-normalized fat mass index (FMI) at 1 year of life. MATERIALS AND METHODS: We carried out a prospective cohort study in 2 groups: late preterm infants and full term infants. We obtained BC data by BIA. We calculated the fat mass (FM), FMI, fat-free mass (FFM) and length-normalized fat-free mass index (FFMI) at 1, 6 and 12 months of life. After, we assessed the association of the FMI with anthropometric parameters using multiple linear regression analysis. RESULTS: The study included 97 late preterm and 47 full term infants, although at 12 months of life, the BC assessment was performed on 66 and 33 infants, respectively. Late preterm infants, compared to full term infants, had a higher FFM at 1 month (4013 vs 3524 g), a higher weight velocity at 6 months (5480 g versus 4604 g) and a lower FFM (7232 vs 7813 g) and FFMI (12.55 vs 13.26) at 12 months of life. The multivariate regression analysis showed that the weight-for-length z-core at 12 months was positively associated with the FMI at 12 months in all infants. CONCLUSION: The weight-for-length z-score at 12 months is strongly associated with the FMI at 1 year of life. Further studies are needed to investigate whether an increment in this anthropometric parameter may modulate the risk of chronic diseases.

Changes from 1986 to 2018 in the prevalence of obesity and overweight, metabolic control and treatment in children with type 1 diabetes mellitus in a Mediterranean area of Southeast Spain.

BACKGROUND: In recent decades, a global increase in the prevalence of childhood overweight and obesity has been observed in children and adolescents with type 1 diabetes. METHODS: This retrospective, cross-sectional, population study examined three groups (1986, 2007, and 2018) of children and adolescents aged < 16 years diagnosed with type 1 diabetes. Overweight and obesity were defined according to the World Health Organization recommendations. RESULTS: The prevalence of overweight and obesity in diabetic children and adolescents was 30.2% (95% CI: 23.1-38.3). There was a significant increase from 1986 to 2007 (11.9% to 41.7%, p = 0.002) and from 1986 to 2018 (11.9% to 34.8%, p = 0.012), but no significant differences were found from 2007 to 2018 (41.7% to 34.8%, p = 0.492). The age at diagnosis was lower in the group with excess body mass (p = 0.037). No significant differences were observed in age (p = 0.690), duration of diabetes (p = 0.163), distribution according to sex (p = 0.452), metabolic control (HbA1c, p = 0.909), or insulin units kg/day (p = 0.566), between diabetic patients with overweight or obesity and those with normal weight. From 2007 to 2018, the use of insulin analogs (p = 0.009) and a higher number of insulin doses (p = 0.007) increased significantly, with no increase in the prevalence of overweight and obesity. CONCLUSIONS: The prevalence of overweight and obesity in diabetic children and adolescents increased in the 1990s and the beginning of the twenty-first century, with stabilization in the last decade. Metabolic control and DM1 treatment showed no association with this trend.

Weight loss thresholds to detect early hypernatremia in newborns / Limites de perda de peso para detecção de hipernatremia precoce em recém-nascidos

ABSTRACT Objective: The literature indicates a single universal cut-off point for weight loss after birth for the risk of hypernatremia, without considering other factors. The aim of this study was to construct and internally validate cut-off points for the percentage weight loss associated with the risk of hypernatremia, taking into account risk factors. Methods: A prospective study with a three-day follow-up was conducted in 165 neonates with a gestational age ≥35 weeks. The main outcome variable was mild or moderate hypernatremia (serum sodium ≥ 145 mmol/L). Secondary variables (risk factors) were maternal and infant variables. A multivariate logistic regression model was constructed to predict hypernatremia, obtaining its probability and the optimal discriminant cut-off point for hypernatremia (receiver operating characteristic analysis). Based on this point, threshold weight loss values were obtained according to the other variables. These values were internally validated by bootstrapping. Results: There were 51 cases (30.9%) of hypernatremia. The mean percentage weight loss for hypernatremic infants was 8.6% and 6.0% for the rest. Associated variables in the multivariate model included greater weight loss, male gender, higher education level, multiparity, and cesarean delivery. The model had an area under the receiver operating characteristic curve of 0.84 (sensitivity = 77.6%; specificity = 73.2%). Similar values were obtained in the bootstrapping validation. The lowest percentage weight loss was 4.77%, for cesarean delivery in male infants of mothers with a higher education level. Conclusions: The weight loss percentage values depended on the type of delivery, parity, newborn gender, and level of maternal education. External studies are required to validate these values.

RESUMO Objetivo: A literatura indica um único ponto de corte universal na perda de peso após o nascimento para risco de hipernatremia, sem considerar outros fatores. Nosso objetivo foi criar e validar internamente pontos de corte para o percentual de perda de peso associado ao risco de hipernatremia considerando fatores de risco. Métodos: Foi feito um estudo prospectivo que incluiu 165 neonatos com idade gestacional ≥ 35 semanas, acompanhados por três dias. A principal variável de resultado foi hipernatremia leve ou moderada (sódio sérico ≥ 145 mmol/L). As variáveis secundárias (fatores de risco) foram variáveis maternas e dos neonatos. Um modelo multivariado de regressão logística foi criado para diagnosticar hipernatremia, obteve sua probabilidade e o ponto de corte discriminativo ideal para hipernatremia (análise da Característica de Operação do Receptor). Com base nesse ponto, obtivemos então os valores limites de perda de peso de acordo com as outras variáveis. Esses valores foram internamente validados por. Resultados: Há 51 casos (30,9%) de hipernatremia. O percentual de perda de peso para neonatos hipernatrêmicos foi 8,6% e 6,0% para o restante. As variáveis associadas no modelo multivariado incluíram maior perda de peso, sexo masculino, maior nível de escolaridade, multiparidade e cesárea. O modelo apresentou uma área sob a curva da Característica de Operação do Receptor de 0,84 (sensibilidade = 77,6%; especificidade = 73,2%). Valores semelhantes foram obtidos na validação da bootstrapping. O menor percentual de perda de peso foi 4,77% para cesárea em neonatos do sexo masculino de mães com maior nível de escolaridade. Conclusões: Os valores percentuais de perda de peso dependem do tipo de parto, paridade, sexo do recém-nascido e nível de escolaridade materna. São necessários estudos externos para validar esses valores.

Zinc concentration in preterm newborns at term age, a prospective observational study.

OBJECTIVES: To determine zinc concentrations and associated factors in a population of preterm newborns at term age. DESIGN: This analytical, descriptive, observational and prospective study was conducted in the neonatal unit of a tertiary hospital. Preterm newborn between gestational weeks 24 and 34 were included in the study. The patients were recruited close to the date of birth. Their clinical histories were collected, and the serum zinc concentrations (SZCs) at gestational weeks 37-41 were measured. This study aimed to measure SZC in a population of preterm newborns at term age, and analyse the anthropometric, clinical and nutritional parameters associated with a decrease in SZC. RESULTS: Overall, 83 preterm subjects were evaluated, including 44 (53%) female infants and 39 (47%) male infants. The median period of gestation was 31 (IQ25-IQ75: 29-33) weeks, and the mean weight at birth was 1.523±0.535 kg. The median SZC at term was 4.4 (IQ25-IQ75: 2.6-6.9) µmol/L. There were some variables associated with zinc concentrations like bronchopulmonary dysplasia (BPD), weight at birth, z-score of length at discharge, being small for gestational age and treatment with recombinant human erythropoietin, although the unique variable that was independent of the other variables in the multivariate analysis (p 0.01) was BPD. Preterm newborn with BPD had lower SZC at term age than those without (2.7 vs 4.9 µmol/L, p 0.005). CONCLUSIONS: Zinc concentrations in this preterm population were low. BPD was significantly and negatively correlated with zinc concentrations. CLINICAL TRIAL REGISTRATION: NCT03532555.

Weight loss thresholds to detect early hypernatremia in newborns.

OBJECTIVE: The literature indicates a single universal cut-off point for weight loss after birth for the risk of hypernatremia, without considering other factors. The aim of this study was to construct and internally validate cut-off points for the percentage weight loss associated with the risk of hypernatremia, taking into account risk factors. METHODS: A prospective study with a three-day follow-up was conducted in 165 neonates with a gestational age ≥35 weeks. The main outcome variable was mild or moderate hypernatremia (serum sodium≥145mmol/L). Secondary variables (risk factors) were maternal and infant variables. A multivariate logistic regression model was constructed to predict hypernatremia, obtaining its probability and the optimal discriminant cut-off point for hypernatremia (receiver operating characteristic analysis). Based on this point, threshold weight loss values were obtained according to the other variables. These values were internally validated by bootstrapping. RESULTS: There were 51 cases (30.9%) of hypernatremia. The mean percentage weight loss for hypernatremic infants was 8.6% and 6.0% for the rest. Associated variables in the multivariate model included greater weight loss, male gender, higher education level, multiparity, and cesarean delivery. The model had an area under the receiver operating characteristic curve of 0.84 (sensitivity=77.6%; specificity=73.2%). Similar values were obtained in the bootstrapping validation. The lowest percentage weight loss was 4.77%, for cesarean delivery in male infants of mothers with a higher education level. CONCLUSIONS: The weight loss percentage values depended on the type of delivery, parity, newborn gender, and level of maternal education. External studies are required to validate these values.

Multivariate Analysis of Thyrotropin in Preterm Newborns Based on Adequacy of Weight for Gestational Age.

BACKGROUND: Different and conflicting data have been published concerning thyrotropin (TSH) levels among small-for-gestational-age (SGA) and appropriate-for-gestational-age (AGA) newborns. The hypothesis of this study was that SGA preterm infants have higher TSH levels than those who are not underweight do. METHODS: This cross-sectional study analyzed the TSH levels of all preterm newborns with a negative congenital hypothyroidism screening result (TSH <7.5 µIU/mL). Secondary variables were sex, birth weight (SGA, AGA), days of life at blood extraction, maternal origin, gestational age, and being a twin or not. Two multiple linear regression models were constructed comparing TSH levels in SGA and AGA or the z-score for birth weight and the remaining variables. RESULTS: A sample including 5819 preterm infants was obtained: 53.8% male, 23.3% twins, and 3.3% SGA. TSH concentrations were 2.16 ± 2.0 µIU/mL for the SGA infants and 1.80 ± 1.5 µIU/mL for the AGA infants (p = 0.012), with a negative correlation (p < 0.001) between TSH levels and the z-score for the weight of the newborn. The multivariate analysis comparing TSH levels between SGA and AGA gave the following: SGA (B = 0.46, p < 0.001), Latin American mother (B = -0.16, p = 0.029), days of life at blood extraction (B = -0.26, p < 0.001), and gestational age ≤28 weeks (B = -0.56, p < 0.001). Using the z-score for the weight, the associations were: maternal origin North Africa (B = 0.19, p = 0.042), days of life at blood extraction (B = -0.27, p < 0.001), gestational age ≤28 weeks (B = -0.55, p < 0.001), and z-score for weight (B = -0.12, p < 0.001). CONCLUSIONS: Our multivariate analysis suggests that TSH concentrations are higher in SGA infants than they are in AGA infants, and this should be taken into account when establishing a reference interval appropriate for this population. The clinical relevance remains unknown, but lines of research are opened that may allow a better understanding of the long-term morbidities in these newborns.

Lung function gain in preterm infants with and without bronchopulmonary dysplasia.

OBJECTIVES: The aim of our study was to determine whether the development of lung function, during the first 2 years of life, is different in preterm infants who suffered or did not suffer from Bronchopulmonary dysplasia (BPD). We also assessed the role of nutritional status and growth in that development. METHODS: Lung function tests were performed in 71 preterm infants at two time points: 6 months of corrected age and 1 year after. FVC, FEV0.5, FEF75 , and FEF25-75 were obtained from maximal expiratory volume curves by means of the raised volume rapid thoraco-abdominal compression technique. RESULTS: When comparing lung function measurements, we found that FVC (P = 0.033) FEV0.5 (P = 0.044), FEF75 (P = 0.014), and FEF25-75 (P = 0.036) were significantly lower in BPD infants. We did not find any catch-up of lung function during the study time, in neither the whole group of children nor within the BPD or non-BPD groups. The increase in lung function was directly proportional to the increase in weight and length. The multivariate analysis showed that the increase in z-score of FVC (P = 0.043), FEV0.5 (P = 0.015), and FEF75 (P = 0.042), was related with the height velocity during the study period. CONCLUSIONS: Infants who suffered from BPD have lower lung function (FVC, FEV0.5 , FEF75 , and FEF25-75 ), than those non-BPD, at two different time points 1 year apart. During the study period, there was no lung function catch-up in either BPD or non-BPD infants. The increase in length is closely associated to the increase in lung function. Pediatr Pulmonol. 2016; 51:936-942. © 2016 Wiley Periodicals, Inc.

Highest Plasma Phenylalanine Levels in (Very) Premature Infants on Intravenous Feeding; A Need for Concern.

OBJECTIVE: To analyse the association in newborns between blood levels of phenylalanine and feeding method and gestational age. STUDY DESIGN: This observational, cross-sectional study included a sample of 11,829 infants between 2008 and 2013 in a Spanish region. Data were recorded on phenylalanine values, feeding method [breast, formula, mixed (breast plus formula), or partial or fully intravenous feeding], gestational age in weeks (<32, 32-37, ≥37), gender and days since birth at the moment of blood collection. Outcomes were [phenylalanine] and [phenylalanine] ≥95th percentile. Associations were analysed using multivariate models [linear (means difference) and logistic regression (adjusted odds ratios)]. RESULTS: Higher phenylalanine values were associated with lower gestational age (p<0.001) and with intravenous feeding (p<0.001). CONCLUSION: The degree of prematurity and intravenous feeding influenced the plasma concentration of phenylalanine in the newborn. Caution should be taken in [phenylalanine] for newborns with intravenous feeding, monitoring them carefully. Very preterm infants given the recommended amount of amino acids should also be strictly monitored. These findings should be taken into consideration and call for adapting the amounts to the needs of the infant.

Lung function among infants born preterm, with or without bronchopulmonary dysplasia.

OBJECTIVE: Both healthy preterm infants and those with bronchopulmonary dysplasia (BPD) have poor lung function during childhood and adolescence, although there is no evidence whether prematurity alone explains the reduction in lung function found in BPD infants. Our study seeks to know if lung function, measured in infancy by means of rapid thoracic compression with raised volume technique, is different between preterm infants with and without BPD. METHODS: Lung function was measured in 43 preterm infants with BPD and in 32 preterm infants without BPD at a chronological age range of 2-28 months. Forced vital capacity (FVC), forced expiratory volume at 0.5 sec, and forced expiratory flows at 50, 75, 85%, and 25-75% of FVC were obtained from maximal expiratory volume curves by means of rapid thoracic compression with raised volume technique. Maximal flow at functional residual capacity was measured using rapid thoracic compression at tidal volume. Multiple regression analysis and generalized least squares (GLS) random-effects regression model were used to control for variables such as gender, weeks of gestation, age, birth weight, and tobacco smoke exposure. A sub-analysis was performed in infants born at 28+ weeks of gestation. RESULTS: BPD was associated to significantly lower flows (regression coefficients: -0.51, -0.54, -57, -0.53, and -0.82, respectively for FEF(50), FEF(75), FEF(85), FEF(25-75)). This association was driven by males and maintained in the subgroup of infants born at 28+ weeks of gestation. CONCLUSION: BPD is associated with an additional decrease of lung function during the first 2 years of life in infants born preterm.

Patrón de la distribución de colesterol total y cHDL en niños y adolescentes españoles: estudio RICARDIN / Total cholesterol and HDL cholesterol distribution in Spanish children and adolescents: RICARDIN Study

Fundamento: El estudio RICARDIN -estudio multicéntrico español de los factores de riesgo en la infancia y adolescencia- ha permitido describir los estándares de normalidad del colesterol total en la población escolar española. El presente estudio pretende comparar las medias de colesterol total entre las diferentes provincias españolas participantes en el estudio, y comparar gráficamente las medias de colesterol total con las obtenidas en una revisión internacional, así como describir el patrón de distribución del colesterol total y cHDL a través de modelos matemáticos en función de la edad y el sexo, y compararlos con dos estudios internacionales realizados en Japón y los EE.UU. Sujetos y métodos: Se seleccionaron 10.683 niños y niñas de edades comprendidas entre 6 y 18 años, pertenecientes a 7 provincias españolas (Madrid, Vizcaya, Lugo, Badajoz, Murcia, Asturias y Barcelona). Las muestras de sangre para la determinación del colesterol fueron obtenidas por punción capilar y analizadas mediante química seca con fotómetro. Resultados: Los valores medios de colesterol total de la población española difieren entre provincias y, en general, son consistentemente inferiores a los de la población mundial, aunque el patrón observado en ambas poblaciones es muy parecido. Los niños españoles presentan una tendencia curvilínea del colesterol ascendente-descendente que puede ser estimada por una función cúbica que explica los datos observados en un 89 por ciento de casos. En las niñas se obtuvo el mejor ajuste mediante la función inversa (R2 = 0,40). Los patrones del cHDL en niños españoles ofreció un buen ajuste (R2 = 0,90) mediante una función cúbica, y en las niñas se halló el mejor ajuste con una función cuadrática (R2 = 0,59). Conclusiones: Existen importantes variaciones fisiológicas del colesterol total según la edad y el sexo en la infancia y adolescencia. El patrón del colesterol observado no sigue un modelo lineal sino que presenta un modelo curvilíneo, aspecto importante al valorar clínicamente las determinaciones aisladas de colesterol en niños y adolescentes, ya que los percentiles altos varían según la edad y sexo en esta etapa de la vida. (AU)