The trajectory of head circumference and neurodevelopment in very preterm newborns during the first two years of life: a cohort study

Abstract Objective To evaluate the growth trajectory of head circumference and neurodevelopment, and to correlate head circumference with cognitive, language, and motor outcomes during the first two years. Method Prospective cohort study in a tertiary hospital including 95 newborns under 32 weeks or 1500 g. Neonates who developed major neonatal morbidities were excluded. The head circumference was measured at birth, at discharge, and at term-equivalent age, 1, 3, 5, 12, 18, and 24 months of corrected age, and the Bayley Scales (Bayley-III) were applied at 12, 18 and 24 months of corrected age to assess cognitive, language and, motor domains. Scores below 85 were classified as mild/moderate deficits and scores below 70 as severe deficits. The association between head circumference Z score and Bayley scores was assessed using Pearson's correlation. The study considered a significance level of 0.05. Results There was a decrease of -0.18 in the head circumference Z score between birth and discharge and the catch-up occurred between discharge and 1 month (an increase of 0.81 in the Z score). There was a positive correlation between head circumference and Bayley scores at 18 months. There was also a positive correlation between head circumference at discharge and at 5 months with the three domains of the Bayley. Conclusion Serial measurements of head circumference provide knowledge of the trajectory of growth, with early catch-up between discharge and 1 month, as well as its association with neurodevelopment. Head circumference is therefore a valuable clinical marker for neurodevelopment, especially in very preterm newborns.

Association between preterm infant body composition in the first 3 months of life and preschool age: a cohort study.

Compared with full-term infants, preterm infants have fat-free mass deficit in the first months of life, which increases the risk of metabolic diseases in the future. In this cohort of children born under 32-week gestational age or less than 1500 g, we aimed to evaluate the associations of body composition at term equivalent age and in the first 3 months of life with fat-free mass and fat mass percentage at 4 to 7 years of life. Body composition assessments by air displacement plethysmography and anthropometry were performed at term, at 3 months of corrected age, and at 4 to 7 years of age. Multiple linear regression analysis was used to observe the associations between body composition at these ages. At term, fat mass percentage showed a negative association and fat-free mass a positive association with fat-free mass at 4 to 7 years. The fat-free mass at 3 months and the gain in fat-free mass between term and 3 months showed positive associations with fat-free mass at 4 to 7 years.   Conclusion: Body composition at preschool age is associated with fat-free mass in the first 3 months of life, a sensitive period for the risk of metabolic diseases. What is Known: • Preterm infants have a deficit in fat-free mass and high adiposity at term equivalent age compared to full-term infants. • Fat-free mass reflects metabolic capacity throughout life and therefore is considered a protective factor against the risk of metabolic syndrome. What is New: •Fat-free mass gain in the first 3 months of corrected age is associated with fat-free mass at preschool and school ages. •The first 3 months of life is a sensitive period to the risk of metabolic diseases.

The trajectory of head circumference and neurodevelopment in very preterm newborns during the first two years of life: a cohort study.

OBJECTIVE: To evaluate the growth trajectory of head circumference and neurodevelopment, and to correlate head circumference with cognitive, language, and motor outcomes during the first two years. METHOD: Prospective cohort study in a tertiary hospital including 95 newborns under 32 weeks or 1500 g. Neonates who developed major neonatal morbidities were excluded. The head circumference was measured at birth, at discharge, and at term-equivalent age, 1, 3, 5, 12, 18, and 24 months of corrected age, and the Bayley Scales (Bayley-III) were applied at 12, 18 and 24 months of corrected age to assess cognitive, language and, motor domains. Scores below 85 were classified as mild/moderate deficits and scores below 70 as severe deficits. The association between head circumference Z score and Bayley scores was assessed using Pearson's correlation. The study considered a significance level of 0.05. RESULTS: There was a decrease of -0.18 in the head circumference Z score between birth and discharge and the catch-up occurred between discharge and 1 month (an increase of 0.81 in the Z score). There was a positive correlation between head circumference and Bayley scores at 18 months. There was also a positive correlation between head circumference at discharge and at 5 months with the three domains of the Bayley. CONCLUSION: Serial measurements of head circumference provide knowledge of the trajectory of growth, with early catch-up between discharge and 1 month, as well as its association with neurodevelopment. Head circumference is therefore a valuable clinical marker for neurodevelopment, especially in very preterm newborns.

Trajetória do crescimento e composição corporal das crianças nascidas menores que 32 semanas de idade gestacional ou com peso inferior a 1500 gramas até 4 a 7 anos de idade: estudo de coorte / Growth trajectory and body composition of children born under 32 weeks gestational age or weighing less than 1500 g until 4 to 7 years of age: a cohort study

Introdução: Os recém-nascidos muito pré-termo e com muito baixo peso, apresentam na idade corrigida do termo, uma menor massa livre de gordura e maior adiposidade, em relação aos nascidos a termo. O aumento da gordura corporal na idade corrigida do termo pode ser fisiológico devido a uma adaptação do recém-nascido pré-termo a vida extrauterina. Entretanto, o déficit de massa livre de gordura pode persistir ao longo da vida e reflete uma capacidade metabólica reduzida e, portanto, o maior risco de doenças metabólicas no futuro. Os estudos sobre a composição corporal na idade pré-escolar e escolar de crianças nascidas pré-termo evidenciam resultados conflitantes na literatura. Objetivo: O objetivo deste estudo foi avaliar a composição corporal e o crescimento de crianças nascidas muito pré-termo ou muito baixo peso, entre 4 e 7 anos. Esta pesquisa apresenta como objetivos específicos comparar a composição corporal e o crescimento entre crianças que nasceram pequenas e adequadas para idade gestacional e avaliar associações entre a composição corporal nos primeiros 3 meses de vida com a massa livre de gordura e percentual de gordura entre 4 e 7 anos. Métodos: Estudo de coorte de recém-nascidos menores de 32 semanas de idade gestacional ou peso inferior a 1500 g, no Instituto Nacional em Saúde da Mulher, da Criança e do Adolescente Fernandes Figueira/Fiocruz. Os dados antropométricos e da composição corporal, com o uso da pletismografia por deslocamento de ar, foram coletados nas idades corrigidas do termo e 3 meses, e na idade entre 4 e 7 anos. O teste t de Student e o teste qui-quadrado foram utilizados para comparar o crescimento e a composição corporal entre recém-nascidos pequenos, e adequados para idade gestacional, nas idades corrigidas do termo e 3 meses e na idade entre 4 e 7 anos. A análise de regressão linear múltipla foi realizada para avaliar as associações entre a composição corporal e o sexo masculino nos primeiros 3 meses de vida com a massa livre de gordura e o percentual de gordura na idade entre 4 e 7 anos. Para todas as análises foi considerado o nível de significância de 0,05. Resultados: Os recém-nascidos muito pré-termo, pequenos para idade gestacional, na idade corrigida do termo, apresentaram menor massa livre de gordura e massa de gordura (gramas, percentual e índices) e menor peso, comprimento e perímetro cefálico do que os nascidos adequados para idade gestacional. Aos 3 meses, a massa livre de gordura, índice de massa livre de gordura, peso e comprimento permaneceram menores no grupo dos nascidos pequenos para idade gestacional. Entre 4 e 7 anos a composição corporal e a antropometria foram similares entre os grupos. Na idade corrigida do termo, a massa livre de gordura apresentou associação positiva, e o percentual de gordura associação negativa com a massa livre de gordura aos 4 a 7 anos de idade. Aos 3 meses, a massa livre de gordura apresentou associação positiva com a massa livre de gordura na idade de 4 a 7 anos. O ganho de massa livre de gordura entre o período do termo e 3 meses também apresentou associação positiva com a massa livre de gordura aos 4 a 7 anos de idade. Conclusão: As diferenças na composição corporal observadas nos primeiros 3 meses de vida entre as crianças nascidas pré-termo pequenas e adequadas para idade gestacional, não se mantiveram entre 4 e 7 anos. A composição corporal na idade de 4 a 7 anos, apresentou associações com a massa livre de gordura nos primeiros 3 meses de idade corrigida, sendo este um período sensível para o risco de doenças metabólicas ao longo da vida. Os estudos longitudinais de longo prazo são necessários para melhor avaliar a trajetória da qualidade do crescimento das crianças nascidas muito pré-termo.

Introduction: Very preterm and very low birth weight infants have less fat-free mass and higher adiposity at term corrected age, than those born at term. The increase in fat mass may be physiological due to an adaptation of the preterm newborn to extrauterine life. However, the deficit of fat-free mass may persist throughout life and reflects a reduced metabolic capacity and therefore, increasing the risk of metabolic diseases in the future. Studies on body composition at preschool and school ages of children born preterm show conflicting results in the literature. Objective: The aim of the present study was to evaluate the body composition and growth of children born very preterm and/or very low birth weight, between 4 and 7 years of age. This research presents as specific objectives the comparison of body composition and growth between children born small and adequate for gestational age and to evaluate associations between body composition in the first 3 months of life with fat-free mass and fat percentage between 4 and 7 years of age. Methods: Cohort study of infants younger than 32 weeks of gestational age or less than 1500 g, at the Instituto Nacional em Saúde da Mulher, da Criança e do Adolescente Fernandes Figueira / Fiocruz. Anthropometric and body composition data, using air displacement plethysmography, were collected at term and 3-month corrected ages, and at 4 to 7 years of age. Student's t test and chi-square test were used to compare growth and body composition between small and appropriate for gestational age infants at term and 3-month corrected ages, and at 4 to 7 years of age. A multiple linear regression analysis was performed to evaluate the associations between body composition and male sex in the first 3 months of life with fat-free mass and fat percentage at 4 to 7 years of age. For all analyses, a significance level of 0.05 was considered. Results: The very preterm, small for gestational age infants had had lower fat-free mass and fat mass (grams, percentual and indexes), and lower weight, length, and head circumference than the appropriate for gestational age infants. At 3 months, fat-free mass, fat-free mass index, weight and length remained lower in the small for gestational age group. Between 4 and 7 years, body composition and anthropometry were similar between the groups. At term corrected age, the fat-free mass showed a positive association and the percentage of fat mass a negative association with fat-free mass at 4 to 7 years. At 3 months, fat-free mass showed a positive association with fat-free mass at ages 4 to 7 years. Also, the gain in fat-free mass between term to 3 months was positively associated with fat-free mass ate 4 to 7 years at age. Conclusion: The differences in body composition and anthropometry observed in the first 3 months of life between children born very preterm small and appropriate for gestational age, were not maintained at 4 to 7 years of age. Body composition at preschool and school age shows associations with fat-free mass and % fat mass in the first 3 months of corrected age, and this is a sensitive period for the risk of metabolic diseases. Long-term longitudinal studies are needed to better assess the trajectory of growth quality in children born very preterm.

Influence of gestational and perinatal factors on body composition of full-term newborns / Influência de fatores gestacionais e perinatais na composição corporal de recém-nascidos a termo

Abstract Objective: To evaluate the influence of gestational and perinatal factors on body composition and birth weight of full-term newborns. Method: This was a cross-sectional study, within a prospective cohort, consisting of 124 postpartum women and their newborns. Data included the following: maternal age; ethnicity; pre-gestational body mass index; gestational weight gain; parity; gestational morbidities (hypertension and gestational diabetes mellitus); gestational age at birth; birth weight; and newborn's gender. Anthropometric and body composition data of the newborns were collected using air-displacement plethysmography (PeaPod® Infant Body Composition System-LMI; Concord, CA, USA). The stepwise technique was applied to a multiple linear regression model. Results: The significant variables in the model that explained 84% of the variation in neonatal fat-free mass were: birth weight; maternal age; newborn's gender and gestational age. For body fat mass: birth weight; newborn's gender; gestational arterial hypertension; gestational diabetes; and gestational weight gain. These variables explained 60% and 46% of fat mass, in grams and as a percentage, respectively. Regarding birth weight, the significant factors were gestational age, pre-gestational BMI, and gestational weight gain. Female newborns showed higher body fat mass and male newborns had higher fat-free mass. Conclusion: Gestational and perinatal factors influence neonatal body composition. Early identification of these gestational factors, which may be modifiable, is necessary to prevent obesity and chronic noncommunicable diseases in the future.

Resumo Objetivo: Avaliar a influência de fatores gestacionais e perinatais na composição corporal e no peso de nascimento de recém-nascidos a termo. Método: Estudo transversal, dentro de uma coorte prospectiva, composto por 124 puérperas e seus recém-nascidos. Os dados incluíram: idade materna; etnia; índice de massa corpórea pré-gestacional; ganho de peso gestacional; paridade; morbidades gestacionais, (hipertensão arterial e diabetes mellitus gestacional); idade gestacional do nascimento; peso de nascimento; e sexo do recém-nascido. Os dados antropométricos e de composição corporal dos recém-nascidos foram coletados com a pletismografia por deslocamento de ar (PeaPod®). Foi aplicada a técnica de stepwise no modelo de regressão linear múltipla. Resultados: As variáveis significativas do modelo que explicou 84% da variação da massa livre de gordura neonatal foram: peso de nascimento; idade materna; sexo do recém-nascido; e idade gestacional. Para a massa de gordura corporal: peso de nascimento; sexo do recém-nascido; hipertensão arterial gestacional; diabetes gestacional; e ganho de peso gestacional. Essas variáveis explicaram 60% e 46% da massa de gordura, em gramas e percentual, respectivamente. Em relação ao peso de nascimento os fatores significativos foram: idade gestacional; IMC pré-gestacional; e ganho de peso gestacional. Os recém-nascidos do sexo feminino apresentaram maior massa de gordura corporal e os do sexo masculino maior massa livre de gordura. Conclusão: Fatores gestacionais e perinatais influenciam a composição corporal neonatal. A identificação precoce desses fatores gestacionais, que podem ser modificáveis, é necessária para prevenção de obesidade e de doenças crônicas não transmissíveis no futuro.

Influence of gestational and perinatal factors on body composition of full-term newborns.

OBJECTIVE: To evaluate the influence of gestational and perinatal factors on body composition and birth weight of full-term newborns. METHOD: This was a cross-sectional study, within a prospective cohort, consisting of 124 postpartum women and their newborns. Data included the following: maternal age; ethnicity; pre-gestational body mass index; gestational weight gain; parity; gestational morbidities (hypertension and gestational diabetes mellitus); gestational age at birth; birth weight; and newborn's gender. Anthropometric and body composition data of the newborns were collected using air-displacement plethysmography (PeaPod® Infant Body Composition System-LMI; Concord, CA, USA). The stepwise technique was applied to a multiple linear regression model. RESULTS: The significant variables in the model that explained 84% of the variation in neonatal fat-free mass were: birth weight; maternal age; newborn's gender and gestational age. For body fat mass: birth weight; newborn's gender; gestational arterial hypertension; gestational diabetes; and gestational weight gain. These variables explained 60% and 46% of fat mass, in grams and as a percentage, respectively. Regarding birth weight, the significant factors were gestational age, pre-gestational BMI, and gestational weight gain. Female newborns showed higher body fat mass and male newborns had higher fat-free mass. CONCLUSION: Gestational and perinatal factors influence neonatal body composition. Early identification of these gestational factors, which may be modifiable, is necessary to prevent obesity and chronic noncommunicable diseases in the future.

Growth and body composition of preterm infants less than or equal to 32 weeks: Cohort study.

BACKGROUND: Extremely preterm infants with weights less than the 10th percentile at discharge have a fat-free mass deficit. AIM: To analyze the relationship of weight Z-scores less than -2SD at term age with fat-free mass and fat mass at term age and at 1 and 3 months of corrected age in very preterm infants. STUDY DESIGN: COHORT STUDY: Subjects: Sixty-six preterm infants born before or at 32 weeks gestation with birth weight equal or greater than the 10th percentile for age were included at term age. They were classified according to weight Z-score as either: "term (-)" (n = 18) if weight Z-scores were less -2SD or "term (+)" (n = 48) if the weight Z-scores were equal or greater than -2SD at term age. OUTCOME MEASURES: Growth and body composition by an air displacement plethysmography system and bioimpedance were assessed at term age and 1 and 3 months of corrected age. RESULTS: Lower fat-free mass persisted up to 3 months in the "term (-)" group [4137 g (645) vs 4592 g (707), p < .01]. Fat mass was lower in the "term (-)" group at term and at 1 month but was similar at 3 months of corrected age [1295 g (774) vs 1477 g (782), p = .109]. Weight, length and head circumference Z-scores were lower in the "term (-)" group compared to those in the "term (+)" group. CONCLUSIONS: The lean tissue deficits were maintained in the "term (-)" group while the differences in body fat percentage were not.

A influência de fatores gestacionais e perinatais na composição corporal e crescimento de recém-nascidos a termo e lactentes: estudo de coorte / The influence of gestational and perinatal factors on the body composition and growth of full-term newborns and infants: a cohort study

Introdução: O aumento da prevalência da obesidade mundial, motivou estudos sobre as fases iniciais do desenvolvimento fetal e neonatal. Morbidades gestacionais e fatores perinatais influenciam o ambiente intrauterino com consequências no crescimento e na composição corporal fetal. A avaliação da composição corporal neonatal é um marcador sensível do ambiente intrauterino, podendo ser um preditor de obesidade e doenças crônicas não transmissíveis no futuro. Objetivo: O objetivo desse estudo foi avaliar a influência de fatores gestacionais e perinatais na composição corporal e crescimento de recém-nascidos a termo e lactentes até 4 meses de vida. Métodos: Estudo de coorte, realizado com puérperas e seus recém-nascidos a termo nascidos no Instituto Nacional de Saúde da Criança e do Adolescente, Fernandes Figueira e internados no Alojamento Conjunto deste hospital. Iniciado em Março de 2016. As mulheres foram categorizadas pelo ganho de peso gestacional em adequado, excessivo e insuficiente, de acordo com o Institute of Medicine (2009). Os dados antropométricos e da composição corporal dos recém-nascidos e lactentes, utilizando a pletismografia por deslocamento de ar (PeaPod®), foram avaliados com até 96 horas, 1, 2 e 4 meses de vida. A análise bivariada foi realizada pelo cruzamento das categorias de ganho de peso gestacional com as características gestacionais e neonatais. A análise de regressão linear múltipla foi aplicada para identificar os fatores perinatais relacionados com a composição corporal neonatal. O teste t-student foi utilizado para avaliar diferenças significativas entre o sexo do recém-nascido e os desfechos neonatais. Para todas as análises adotou-se um nível de significância de 5%. Resultados: Cento e vinte quatro puérperas e seus recém-nascidos participaram do estudo, sendo que 46,7% das mulheres apresentaram excesso de peso pré-gestacional e 41,1% ganharam peso excessivo durante a gestação. Os recém-nascidos de mães com ganho de peso excessivo na gestação apresentaram maior peso de nascimento e maior massa de gordura corporal, além de maior escore Z dos índices de peso/idade, e perímetro cefálico/idade e IMC com 96 horas de vida. Os lactentes apresentaram semelhança no crescimento e na composição corporal, com 1, 2 e 4 meses de vida. O modelo estatístico para avaliar a massa de gordura do recém-nascido incluiu: o peso de nascimento, o sexo, a hipertensão arterial gestacional, o diabetes e o ganho de peso gestacional. Estas variáveis explicaram 60% e 46% da massa de gordura, em gramas e percentual, respectivamente. O modelo que explicou 84% da variação da massa livre de gordura neonatal incluiu: o peso de nascimento, a idade materna, o sexo e a idade gestacional. Em relação ao peso de nascimento, os fatores significativos foram: a idade gestacional, o índice de massa corpórea pré-gestacional e o ganho de peso gestacional. Os recém-nascidos do sexo feminino apresentaram maior massa de gordura corporal, enquanto que os do sexo masculino maior massa livre de gordura. Conclusão: O ganho de peso gestacional em excesso, as morbidades maternas e os fatores perinatais, como idade gestacional e peso de nascimento, modificaram a composição corporal neonatal. A detecção precoce dos fatores gestacionais modificáveis relacionados com a adiposidade neonatal, pode ajudar na prevenção de obesidade e doenças crônicas não transmissíveis.