Postnatal growth in small vulnerable newborns: a longitudinal study of 2 million Brazilians using routine register-based linked data.

BACKGROUND: Preterm, low-birth weight (LBW) and small-for-gestational age (SGA) newborns have a higher frequency of adverse health outcomes, including linear and ponderal growth impairment. OBJECTIVE: To describe the growth trajectories and to estimate catch-up growth during the first 5 y of life of small newborns according to 3 vulnerability phenotypes (preterm, LBW, SGA). METHODS: Longitudinal study using linked data from the 100 Million Brazilian Cohort baseline, the Brazilian National Live Birth System (SINASC), and the Food and Nutrition Surveillance System (SISVAN) from 2011 to 2017. We estimated the length/height-for-age (L/HAZ) and weight-for-age z-score (WAZ) trajectories from children of 6-59 mo using the linear mixed model for each vulnerable newborn phenotype. Growth velocity for both L/HAZ and WAZ was calculated considering the change (Δ) in the mean z-score between 2 time points. Catch-up growth was defined as a change in z-score > 0.67 at any time during follow-up. RESULTS: We analyzed 2,021,998 live born children and 8,726,599 observations. The prevalence of at least one of the vulnerable phenotypes was 16.7% and 0.6% were simultaneously preterm, LBW, and SGA. For those born at term, all phenotypes had a period of growth recovery from 12 mo. For preterm infants, the onset of L/HAZ growth recovery started later at 24 mo and the growth trajectories appear to be lower than those born at term, a condition aggravated among children with the 3 phenotypes. Preterm and female infants seem to experience slower growth recovery than those born at term and males. The catch-up growth occurs at 24-59 mo for males preterm: preterm + AGA + NBW (Δ = 0.80), preterm + AGA + LBW (Δ = 0.88), and preterm + SGA + LBW (Δ = 1.08); and among females: term + SGA + NBW (Δ = 0.69), term + AGA + LBW (Δ = 0.72), term + SGA + LBW (Δ = 0.77), preterm + AGA + LBW (Δ = 0.68), and preterm + SGA + LBW (Δ = 0.83). CONCLUSIONS: Children born preterm seem to reach L/HAZ and WAZ growth trajectories lower than those attained by children born at term, a condition aggravated among the most vulnerable.

Hypertriglyceridemic waist phenotype: association with metabolic abnormalities in adolescents.

OBJECTIVE: This study aimed to identify the prevalence of hypertriglyceridemic waist (HTW) phenotype, and to evaluate its association with metabolic abnormalities in adolescents of low socioeconomic status. METHOD: This was a cross-sectional study with a random sample of 1,076 adolescents between 11 and 17 years, of both genders, from public schools. The participants underwent anthropometric measurements (weight, height, and waist circumference), and levels of total cholesterol, low-density-lipoprotein cholesterol (LDL-C), high-density-lipoprotein cholesterol (HDL-C), non-HDL cholesterol, triglyceride (TG), and fasting glucose were measured. Information regarding the socioeconomic status of the participants' families was obtained. The HTW phenotype was defined by the simultaneous presence of increased waist circumference (≥ 90(th) percentile for age and gender) and serum triglyceride levels (≥ 100mg/dL). A logistic regression analysis was used to evaluate the associations of interest. RESULTS: The prevalence of HTW phenotype was 7.2% among the adolescents, being higher in the presence of obesity (63.4%) and high levels of non-HDL cholesterol (16.6%) and LDL-C (13.7%). The bivariate analysis indicated that, of the metabolic variables, only blood glucose was not associated with the HTW phenotype. Multivariate analysis adjusted for age and gender indicated that the HTW phenotype was positively associated with high non-HDL cholesterol (odds ratio: 7.0; 95% CI: 3.9-12.6) and low HDL-C levels (odds ratio: 2.7; 95% CI: 1.5-4.8). CONCLUSIONS: This study demonstrated that the HTW phenotype was associated with an atherogenic lipid profile, and this phenotype is suggested as a screening tool to identify adolescents with metabolic alterations.

Fenótipo cintura hipertrigliceridêmica: associação com alterações metabólicas em adolescentes / Hypertriglyceridemic waist phenotype: association with metabolic abnormalities in adolescents

OBJETIVO: O presente estudo objetivou identificar a prevalência do fenótipo cintura hipertrigliceridêmica (CHT) e avaliar sua associação com alterações metabólicas em adolescentes de baixa condição econômica. MÉTODO: Estudo transversal com amostra probabilística de 1.076 adolescentes entre 11 e 17 anos, de ambos os sexos, estudantes de escolas públicas. Os participantes foram submetidos à avaliação antropométrica (peso, altura e circunferência da cintura) e à dosagem dos níveis de colesterol total, LDL-C, HDL-C, colesterol não HDL, triglicérides (TG) e glicemia de jejum. Foram obtidas informações referentes às condições econômicas das famílias dos participantes.O fenótipo CHT foi definido pela presença simultânea da circunferência da cintura aumentada (> percentil 90 por idade e sexo) e dos níveis séricos de triglicérides elevados (> 100 mg/dL). A análise de regressão logística foi utilizada para avaliação das associações de interesse. RESULTADOS: A prevalência do fenótipo CHT foi de 7,2% entre os adolescentes, sendo mais elevada na presença de obesidade (63,4%), do colesterol não HDL (16,6%) e do LDL-C (13,7%) altos. A análise bivariada indicou que, das variáveis metabólicas, apenas a glicemia não se associou ao fenótipo CHT. A análise multivariada, ajustada por sexo e idade, indicou que o fenótipo CHT se associou positivamente com o colesterol não HDL alto (odds ratio, 7,0; IC 95% 3,9-12,6) e com o HDL-C baixo (odds ratio, 2,7; IC 95%, 1,5-4,8). CONCLUSÕES: Este estudo mostrou que o fenótipo CHT se associou com um perfil lipídico aterogênico e sugere esse fenótipo como uma ferramenta de screening que pode ser utilizada para identificar adolescentes com alterações metabólicas.

OBJECTIVE: This study aimed to identify the prevalence of hypertriglyceridemic waist (HTW) phenotype, and to evaluate its association with metabolic abnormalities in adolescents of low socioeconomic status. METHOD: This was a cross-sectional study with a random sample of 1,076 adolescents between 11 and 17 years, of both genders, from public schools. The participants underwent anthropometric measurements (weight, height, and waist circumference), and levels of total cholesterol, low-density-lipoprotein cholesterol (LDL-C), high-density-lipoprotein cholesterol (HDL-C), non-HDL cholesterol triglyceride (TG), and fasting glucose were measured. Information regarding the socioeconomic status of the participants' families was obtained. The HTW phenotype was defined by the simultaneous presence of increased waist circumference (> 90th percentile for age and gender) and serum triglyceride levels (> 100 mg/dL). A logistic regression analysis was used to evaluate the associations of interest. RESULTS: The prevalence of HTW phenotype was 7.2% among the adolescents, being higher in the presence of obesity (63.4%) and high levels of non-HDL cholesterol (16.6%) and LDL-C (13.7%). The bivariate analysis indicated that, of the metabolic variables, only blood glucose was not associated with the HTW phenotype. Multivariate analysis adjusted for age and gender indicated that the HTW phenotype was positively associated with high non-HDL cholesterol (odds ratio: 7.0; 95% CI: 3.9-12.6) and low HDL-C levels (odds ratio: 2.7; 95% CI: 1.5-4.8). CONCLUSIONS: This study demonstrated that the HTW phenotype was associated with an atherogenic lipid profile, and this phenotype is suggested as a screening tool to identify adolescents with metabolic alterations.