Abstract Background: the biological activity of vitamin D depends on the activity of its receptor or VDR. On the other hand, the activity of this receptor is influenced by its state of methylation. The objective of this study was to verify if the BsmI polymorphism of the VDR gene influences its methylation profile in adolescents. Secondly, it was to verify if the status of some metabolic factors (oxidative stress, inflammation, lipid profile, and glycemia) in the serum, and gender-adjusted vitamin D levels are independent factors with an influence on the VDR methylation profile. Methods and results: the study included 198 adolescents of both sexes, aged 15-19 years, who underwent testing for VDR gene methylation polymorphisms, serum vitamin D levels, and metabolic, oxidative stress, and systemic inflammation markers. It was observed that the BB genotype was less methylated than the other groups (26.1 % versus 30.3 %, and 29.3 % for Bb and bb, respectively), although without statistical differences between them. The odds ratio indicated a protection of 13 % (partially methylated) for vitamin D status, while alpha glycols increased the risk ratio (of being partially methylated) by 3 %. MDA was protective at a 28 % chance of risk that adolescents with higher levels of lipid peroxidation would be hypomethylated. Conclusion: we conclude that the methylation profile of the VDR gene is not influenced by the different BsmI polymorphism genotypes, and that serum vitamin D and serum markers of oxidative stress and inflammation can modulate this profile.

Resumen Antecedentes: la actividad biológica de la vitamina D depende de la actividad de su receptor, el VDR. Por otro lado, la actividad de este receptor está influenciada por su estado de metilación. El objetivo de este estudio es verificar si el polimorfismo BsmI del gen VDR influye en el perfil de metilación del mismo en los adolescentes. En segundo lugar, verificar si los factores metabólicos (estrés oxidativo, inflamación, perfil lipídico y glucemia) del suero y la vitamina D ajustada por sexo actúan independientemente de los polimorfismos sobre el perfil de metilación del VDR. Métodos y resultados: el estudio incluyó a 198 adolescentes de ambos sexos, de 15 a 19 años de edad, que se sometieron a análisis de polimorfismos de metilación del gen VDR, niveles de vitamina D, marcadores metabólicos, estrés oxidativo e inflamación sistémica. Se observó que el genotipo BB estaba menos metilado que los otros grupos (26,1 % contra 30,3 % y 29,3 % para Bb y bb respectivamente), aunque sin diferencias estadísticas entre ellos. El odds ratio indicó una protección del 13 % (parcialmente metilado) para el estado de la vitamina D, mientras que los alfa glicoles aumentaron el índice de riesgo (de estar parcialmente metilado) en un 3 %. La MDA fue protectora con un 28 % de probabilidad de riesgo de que los adolescentes con niveles más altos de peroxidación lipídica fueran hipometilados. Conclusión: concluimos que el perfil de metilación del gen VDR no está influenciado por los diferentes genotipos del polimorfismo BsmI y que la vitamina D y los marcadores de estrés oxidativo e inflamación en el suero pueden modular este perfil.

Abstract Objective: to verify the association of serum concentrations of 25-hydroxyvitamin D and glycemic levels with the genetic variants rs1544410 and rs2228570 of the VDR gene in adolescents from the Northeast region of Brazil. Materials and methods: a cross-sectional epidemiological study with 208 adolescents from public schools in the city of João Pessoa (Paraíba, Brazil) between 15 and 19 years of age. Blood samples were collected for DNA extraction and analysis of polymorphisms rs1544410 and rs2228570, as well as biochemical analyses (25-hydroxyvitamin D, parathyroid hormone, calcium and glycemia). Results: the mean age was 17.7 (± 1.14) years. Half of adolescents had sufficient serum levels of 25-hydroxyvitamin D and the other half had insufficient/deficient vitamin. The most frequent genotypic distribution was bb and Ff and of lesser frequency BB and ff. There was a significant relationship between the genotypes of rs1544410 and glycemia values (p = 0.049) in the relationships between the genotypes BBxbb (p = 0.012) and Bbxbb (p = 0.037); (p = 0.036, OR = 2.15, 95 % CI = 1.05-4.41), and in the BB+Bb group analysis when compared to the bb (p = 0.025, OR = 1.89, 95 % CI = 1.08-3.29) presented higher risk of glycemia above the median. On the other hand, when Bb+bb was analyzed in relation to BB, adolescents had a greater chance of blood glucose below the median (p = 0.025, OR = 0.66, CI = 0.47-0.95). Conclusion: this study showed a significant relation of glycemia with the distribution of rs1544410 polymorphism genotypes.

Resumen Objetivo: verificar la asociación de las concentraciones séricas de 25-hidroxivitamina D y los niveles de glucemia con las variantes genéticas rs1544410 y rs2228570 del gen VDR en adolescentes de la región noreste de Brasil. Materiales y métodos: se realizó un estudio epidemiológico transversal con 208 adolescentes de escuelas públicas en la ciudad de João Pessoa (Paraíba, Brasil) de entre 15 y 19 años de edad. Se recogieron muestras de sangre para la extracción de ADN y el análisis de los polimorfismos rs1544410 y rs2228570, así como para análisis bioquímicos (25-hidroxivitamina D, hormona paratiroidea, calcio y glucemia). Resultados: la edad media fue de 17,7 (± 1,14) años. La mitad de los adolescentes tenía niveles séricos suficientes de 25-hidroxivitamina D y la otra mitad, vitamina insuficiente/deficiente. La distribución genotípica más frecuente fue bb y Ff y la de menor frecuencia, BB y ff. Hubo una relación significativa entre los genotipos de rs1544410 y los valores de glucemia (p = 0,049) en las relaciones entre los genotipos BBxbb (p = 0,012) y Bbxbb (p = 0,037); (p = 0,036, OR = 2,15, IC 95 % = 1,05-4.41), y el análisis del grupo BB + Bb en comparación con el bb (p = 0,025, OR = 1,89, IC 95 % = 1,08-3,29) mostró un mayor el riesgo de glucemia, por encima de la mediana. Por otro lado, cuando se analizó Bb+bb en relación con la BB, los adolescentes tuvieron una mayor probabilidad de que la glucosa en sangre estuviera por debajo de la mediana (p = 0,025, OR = 0,66, IC = 0,47-0,95). Conclusión: este estudio mostró una relación significativa entre la glucemia y la distribución de genotipos de polimorfismo rs1544410.

RESUMO Objetivo Esta pesquisa teve por objetivo investigar a associação do perfil hematológico com os valores séricos de 25-hidroxivitamina D e polimorfismo FokI do gene receptor da vitamina D em indivíduos com fibrose cística, acompanhados em um centro de referência do Nordeste Brasileiro. Métodos Trata-se de estudo transversal, realizado com 18 indivíduos com fibrose cística, de ambos os sexos, com idade entre zero e 25 anos. Foram coletadas informações sociodemográficas e investigados fatores associados à exposição solar. Também foram aferidas medidas antropométricas de peso, estatura e circunferência do braço. O sangue foi coletado para análise dos parâmetros bioquímicos (25-hidroxivitamina D, paratormônio, cálcio e hemograma) e verificação da presença do polimorfismo FokI do gene receptor da vitamina D. Resultados Da amostra total, 33,33% (n=6) apresentaram insuficiência/deficiência de vitamina D (19.60 ±6.180 ng/ml), e 27,8% (n=5) acusaram anemia e baixo peso para a idade. No tocante aos genótipos, 5,6% (n=1) apresentaram genótipo FF, 72,3% (n=13) apresentaram genótipo Ff e 22,2% (n=4) apresentaram genótipo ff. Houve associação entre os valores séricos de 25-hidroxivitamina D e os de hemoglobina (p=0.008), hematócrito (p=0.019) e leucócitos (p=0.0114). Não houve associação entre os valores de 25-hidroxivitamina D e os genótipos (FF, Ff e ff) (p=0.2451). Além disso, houve associação entre o polimorfismo FokI e a contagem total de leucócitos (p=0.01). Conclusão O presente estudo encontrou associação entre os valores séricos de 25-hidroxivitamina D e os de hemoglobina, hematócrito e leucócitos nos indivíduos analisados. Além disso, encontrou-se associação do polimorfismo FokI com a contagem total de leucócitos.

ABSTRACT Objective The present study aimed at investigating the association between hematological profile and serum 25-hydroxyvitamin D (25[OH]D) levels and Fokl polymorphism of the vitamin D receptor gene in individuals with Cystic Fibrosis. Methods A cross-sectional study that involved 18 men and women aged 0-25 years with Cystic Fibrosis. Socio-demographic information and the factors associated with sun exposure were obtained. Weight, height, and arm circumference were also measured. Blood sample was collected for the analysis of biochemical parameters (25[OH]D, parathyroid hormone, and calcium levels and blood count) and for the validation of the presence of FokI polymorphism in the vitamin D receptor gene. Results Among the participants, 33.33% (n=6) had vitamin D deficiency (19.60±6.180 ng/mL), and 27.8% (n=5) presented with anemia and low weight for age. In terms of genotype, 5.6% (n=1) presented with the FF genotype, 72.3% (n=13) had the Ff genotype, and 22.2% (n=4) had the ff genotype. Serum 25(OH)D levels were associated with hemoglobin (p=0.008) and hematocrit (p=0.019) levels and leukocyte count (p=0.0114). No association was observed between 25(OH)D levels and the genotypes (FF, Ff, and ff) (p=0.2451). In addition, an association was observed between FokI polymorphism and the total leukocyte count (p=0.01). Conclusion An association was observed between serum 25(OH)D levels and hemoglobin and hematocrit levels and leukocyte count in individuals with Cystic Fibrosis. Moreover, FokI polymorphism was associated with total leukocyte count.

Background: Hypovitaminosis D is a frequent problem in the world and can be influenced by several factors. Objective: To estimate the prevalence of hypovitaminosis D and associated factors in adolescent students of a capital city of northeastern Brazil. Methods: Cross-sectional epidemiological study assessing 220 school adolescents of both sexes aged 15 to 19 years. A questionnaire was applied to assess sociodemographic (skin color, mother's education and receiving social benefits) and behavioral data (number of hours of sleep per day, sun exposure, physical activity and dietary vitamin D intake). Anthropometric nutritional status was assessed by BMI (body mass index) for age. Serum 25 (OH) D concentrations, PTH and serum calcium were measured by blood samples. We identified individuals with hypovitaminosis D as those with 25 (OH) D < 30 ng/dL. The analysis of factors associated with hypovitaminosis D was performed by simple and multivariate Poisson Regression. Results: The prevalence of hypovitaminosis D was 57.3%. The female population had a significantly higher prevalence than the male. In the final adjusted model, the variable independently associated with hypovitaminosis D in females was the lowest serum calcium concentrations, and for males it was BMI, in which adolescents who had overweight/obesity were 2.4 times more likely to have hypovitaminosis D than the eutrophic ones. Conclusions: The present study found a high prevalence of hypovitaminosis D in the analyzed population, especially in female adolescents. In addition, the factors independently associated with hypovitaminosis D were found to be overweight/obese in boys and low calcium concentrations in girls.

Introducción: la hipovitaminosis D es un problema frecuente en el mundo y puede verse influenciada por varios factores. Objetivo: estimar la prevalencia de hipovitaminosis D y factores asociados en adolescentes de una ciudad capital del noreste de Brasil. Métodos: estudio epidemiológico transversal que evaluó a 220 adolescentes de ambos sexos de 15 a 19 años de edad. Se aplicó un cuestionario para evaluar los datos sociodemográficos y de comportamiento. El estado nutricional antropométrico fue evaluado por IMC para la edad. Las concentraciones séricas de 25 (OH) D, PTH y calcio en suero se midieron mediante muestras de sangre. Se identificaron individuos con hipovitaminosis D como aquellos con 25 (OH) D < 30 ng/dl. El análisis de factores asociados con la hipovitaminosis D se realizó mediante Regresión de Poisson simple y multivariante. Resultados: la prevalencia de hipovitaminosis D fue del 57,3%. La población femenina tenía una prevalencia significativamente mayor que la masculina. En el modelo ajustado final, la variable independientemente asociada con la hipovitaminosis D en las mujeres fue la más baja de las concentraciones séricas de calcio, y para los hombres fue el IMC, en el que los adolescentes con sobrepeso/obesidad tenían 2,4 veces más probabilidades de tener hipovitaminosis que los eutróficos. Conclusiones: el presente estudio encontró una alta prevalencia de hipovitaminosis D en la población analizada, especialmente en adolescentes. Además, se encontró que los factores asociados de forma independiente con la hipovitaminosis D fueron el sobrepeso/obesidad en los niños y concentraciones bajas de calcio en las niñas.

RESUMO Objetivo: Investigar a associação do perfil hematológico com os níveis séricos de 25-hidroxivitamina D e polimorfismo BsmI do gene vitamina D receptor de idosos não institucionalizados. Métodos: Estudo transversal realizado com 142 idosos de ambos os sexos. Foram coletadas, por meio de um questionário, informações sociodemográficas, antecedentes clínicos e fatores associados à exposição solar. Além disso, foram aferidas medidas antropométricas de peso, altura e circunferência da cintura. Material biológico foi coletado para análise dos parâmetros bioquímicos (25-hidroxivitamina D, parathormone, cálcio sérico, ureia, creatinina, enzimas hepáticas e perfil hematológico) e para identificação do polimorfismo BsmI do gene vitamina D receptor. Resultados: Os participantes do estudo eram, em sua maioria, do sexo feminino (80,3%) e apresentaram concentrações médias de 25-hidroxivitamina D, hemoglobina e hematócrito de 32,1±7,3 ng/dL, 13,5±1,5 d/dL e 40,0±4,4%, respectivamente. Da amostra total, 40,8% (n=58) apresentaram insuficiência/deficiência de vitamina D (25,7±3,3 ng/mL) e 12,6% (n=18), anemia. Encontrou-se associação entre as concentrações séricas de vitamina D com as de hemoglobina (p=0,030) e hematócrito (p=0,032). Entretanto, quando os sujeitos foram categorizados quanto à presença ou não de anemia, essa associação não se manteve (p=0,270). Além disso, não foi observada relação entre o polimorfismo BsmI e as concentrações de hemoglobina e hematócrito nos grupos de idosos com suficiência ou insuficiência/deficiência de vitamina D. Conclusão: O presente estudo encontrou associação entre as concentrações séricas de vitamina D e as de hematócrito e hemoglobina nos idosos analisados. Contudo, não foram observadas associações entre esses parâmetros hematológicos e o polimorfismo BsmI do gene vitamina D receptor.

ABSTRACT Objective: To investigate the association between serum level of 25-hydroxy vitamin D and the Vitamin D Receptos gene BsmI polymorphism in the blood profile of community-dwelling older adults. Methods: This cross-sectional study included 142 older males and females. A questionnaire collected socio demographic information, medical history, and factors associated with sun exposure. Weight, height, and waist circumference were measured. Biological material was collected to analyze biochemical parameters 25-hydroxy vitamin D, parathormone, serum calcium, urea, creatinine, liver enzymes, and blood profile) and to verify the presence of the vitamin D receptos gene BsmI polymorphism. Results: Most participants were female (80.3%). The mean levels of 25-hydroxy vitamin D, hemoglobin, and hematocrit were 32.1±7.3 ng/dL, 13.5±1.5 d/dL, and 40.0±4.4%, respectively. Fifty-eight (40.8%) participants had vitamin D insufficiency/deficiency (25.7±3.3 ng/mL), and 18 (12.6%) had anemia. Serum vitamin D was associated with hemoglobin (p=0.030) and hematocrit (p=0.032). However, when subjects were categorized as anemic or not anemic, said association was not maintained (p=0.270). Moreover, the BsmI polymorphism was not associated with hemoglobin and hematocrit levels, regardless of vitamin D status. Conclusion: The serum level of vitamin D is associated with hematocrit and hemoglobin levels in older adults. However, these blood parameters were not associated with the vitamin D receptor gene BsmI polymorphism.

RESUMO Objetivo Identificar a prevalência da utilização de suplemento alimentar em recém-nascidos e avaliar as características, os solicitantes e os motivos justificados para sua utilização em um "Hospital Amigo da Criança". Métodos Trata-se de estudo do tipo transversal, realizado com 113 díades mãe e filho de um hospital universitário com o título de "Amigo da Criança", no período de agosto de 2012 a fevereiro de 2013. A partir de um questionário estruturado, foram coletadas informações sociodemográficas, antecedentes obstétricos, condições de nascimento da criança, características do suplemento e prescritores. Foi realizada análise descritiva e inferencial (teste Qui-quadrado de Pearson), aceitando um nível de significância p?0,05, com intervalo de confiança de 95%. Resultados A prevalência de indicação de suplemento alimentar foi de 16,0%, com menor aderência para os nascidos nas primeiras horas do dia (p=0,006). O profissional de enfermagem foi o que mais solicitou o suplemento (54,0%), e no menor tempo (1 a 6 horas) após o nascimento da criança (p=0,05). Quanto aos motivos de indicação, apenas 6,2% atenderam às recomendações da Iniciativa Hospital Amigo da Criança, destacando-se a hipogalactia como principal motivo (71,7%), com maior probabilidade de indicação para os recém-nascidos de parto cesáreo (p<0,02). Conclusão Apesar do título de "Hospital Amigo da Criança", foram identificadas inúmeras indicações de suplemento ali-mentar desnecessárias e precipitadas, o que pode dificultar o aleitamento materno e favorecer o desmame precoce, sugerindo a necessidade de uma avaliação mais criteriosa na indicação pela equipe assistencial.

ABSTRACT Objective To identify the prevalence of infant formula use and assess the characteristics, requesters, and reasons that justify its use in a Baby-Friendly Hospital. Methods This cross-sectional study included 113 mother/child dyads from a university hospital with the title "Baby-Friendly Hospital" from August 2012 to February 2013. A structured questionnaire collected sociodemographic data, obstetric history, newborn birth conditions, infant formula characteristics, and prescribers. Descriptive and inferential analyses (Pearson's Chi-square test) were conducted using a significance level of p?0.05 and a 95% confidence interval. Results The prevalence of infant formula prescription was of 16.0%, with smaller adherence in infants born in the first hours of the day (p=0.006). Nurses made the most requests (54.0%) and in the shortest period of time (1 to 6 hours) after delivery (p=0.05). Only 6.2% of the requests complied with the recommendations made by Baby-Friendly Hospitals, and the main reason for the request was hypogalactia (71.7%). Infant formula was more likely to be indicated to infants born by cesarean section (p<0.02). Conclusion Despite the title "Baby-Friendly Hospital", numerous unnecessary and hasty infant formula indications were identified, which may hinder breastfeeding and favor early weaning, suggesting that the care team needs to assess infant formula indication more thoroughly.