Association between socioeconomic and biological factors and infant weight gain: Brazilian Demographic and Health Survey - PNDS-2006/07 / Associação entre fatores socioeconômicos e biológicos e o ganho de peso de lactentes: Pesquisa Nacional de Demografia e Saúde (PNDS) de 2006/07

OBJECTIVE: To examine the associations between socioeconomic and biological factors and infant weight gain. METHODS: All infants (0-23 months of age) with available birth and postnatal weight data (n = 1763) were selected from the last nationally representative survey with complex probability sampling conducted in Brazil (2006/07). The outcome variable was conditional weight gain (CWG), which represents how much an individual has deviated from his/her expected weight gain, given the birth weight. Associations were estimated using simple and hierarchical multiple linear regression, considering the survey sampling design, and presented in standard deviations of CWG with their respective 95% of confidence intervals. Hierarchical models were designed considering the UNICEF Conceptual Framework for Malnutrition (basic, underlying and immediate causes). RESULTS: The poorest Brazilian regions (-0.14 [-0.25; -0.04]) and rural areas (-0.14 [-0.26;-0.02]) were inversely associated with CWG in the basic causes model. However, this association disappeared after adjusting for maternal and household characteristics. In the final hierarchical model, lower economic status (-0.09 [-0.15; -0.03]), human capital outcomes (maternal education < 4th grade (-0.14[-0.29; 0.01]), higher maternal height (0.02[0.01; 0.03])), and fever in the past 2 weeks (-0.13[-0.26; -0.01]) were associated with postnatal weight gain. CONCLUSION: The results showed that poverty and lower human capital are still key factors associated with poor postnatal weight gain. The approach used in these analyses was sensitive to characterize inequalities among different socioeconomic contexts and to identify factors associated with CWG in different levels of determination. .

OBJETIVO: Examinar as associações entre fatores socioeconômicos e biológicos e o ganho de peso de lactentes. MÉTODOS: Foram selecionados todos os lactentes (0-23 meses de idade) com dados de peso ao nascer e pós-natal avaliados na última pesquisa com representatividade nacional realizada no Brasil (2006/07) por amostragem probabilística complexa. A variável de resultado foi o Evolução Ponderal Condicional (CWG), que representa quanto um indivíduo desviou de seu ganho de peso esperado, considerando o peso ao nascer. As associações foram estimadas utilizando regressão linear simples e múltipla hierárquica, considerando o plano amostal da pesquisa e apresentadas em desvios padrão do CWG com seus respectivos intervalos de confiança de 95%. Os modelos hierárquicos foram estruturados considerando o Modelo Conceitual de Desnutrição da UNICEF (causas básicas, inerentes e imediatas). RESULTADOS: As regiões brasileiras mais pobres (-0,14 [-0,25; -0,04]) e a área rural (-0,14 [-0,26; -0,02]) foram inversamente associadas ao CWG no modelo de causas básicas. Contudo, essa associação desapareceu após o ajuste pelas características maternas e do ambiente familiar. No modelo hierárquico final, a baixa condição econômica (-0,09 [-0,15; -0,03]), as variáveis de capital humano (escolaridade materna < 5° ano (-0,14 [-0,29; 0,01])), maior estatura materna (0,02 [0,01; 0,03])) e febre nas duas semanas anteriores à pesquisa (-0,13 [-0,26; -0,01]) foram inversamente associadas ao ganho de peso pós-natal. CONCLUSÃO: Os resultados mostraram que a pobreza e baixo capital humano ainda são fatores fundamentais associados ao ganho de peso pós-natal abaixo de esperado. A abordagem utilizada em nossas análises foi sensível ao caracterizar desigualdades entre diferentes contextos socioeconômicos e ao identificar fatores associados ao CWG em diferentes níveis de determinação. .

Association between socioeconomic and biological factors and infant weight gain: Brazilian Demographic and Health Survey--PNDS-2006/07.

OBJECTIVE: To examine the associations between socioeconomic and biological factors and infant weight gain. METHODS: All infants (0-23 months of age) with available birth and postnatal weight data (n = 1763) were selected from the last nationally representative survey with complex probability sampling conducted in Brazil (2006/07). The outcome variable was conditional weight gain (CWG), which represents how much an individual has deviated from his/her expected weight gain, given the birth weight. Associations were estimated using simple and hierarchical multiple linear regression, considering the survey sampling design, and presented in standard deviations of CWG with their respective 95% of confidence intervals. Hierarchical models were designed considering the UNICEF Conceptual Framework for Malnutrition (basic, underlying and immediate causes). RESULTS: The poorest Brazilian regions (-0.14 [-0.25; -0.04]) and rural areas (-0.14 [-0.26;-0.02]) were inversely associated with CWG in the basic causes model. However, this association disappeared after adjusting for maternal and household characteristics. In the final hierarchical model, lower economic status (-0.09 [-0.15; -0.03]), human capital outcomes (maternal education < 4th grade (-0.14[-0.29; 0.01]), higher maternal height (0.02[0.01; 0.03])), and fever in the past 2 weeks (-0.13[-0.26; -0.01]) were associated with postnatal weight gain. CONCLUSION: The results showed that poverty and lower human capital are still key factors associated with poor postnatal weight gain. The approach used in these analyses was sensitive to characterize inequalities among different socioeconomic contexts and to identify factors associated with CWG in different levels of determination.

Secular trends and factors associated with overweight among Brazilian preschool children: PNSN-1989, PNDS-1996, and 2006/07 / Tendência secular e fatores associados ao excesso de peso entre pré-escolares brasileiros: PNSN-1989, PNDS-1996 e 2006/07

OBJECTIVE: to describe the secular trends in overweight among preschool children in the years 1989, 1996, and 2006, and to identify risk factors associated with this condition in 2006. METHODS: anthropometric data from three surveys (1989, 1996, and 2006) with a representative sample of the population were analyzed. Overweight was defined as the weight-for-height Z-score. The multivariable models of overweight association with risk factors were generated by Poisson regression, and the estimates were shown as prevalence ratios with their respective 95% confidence intervals (PR [95% CI]). RESULTS: throughout the 17-year period studied, the relative prevalence of overweight in preschoolers increased by 160% in Brazil, representing an increase of 9.4% per year. Based on data from the National Survey on Demography and Health of Women and Children - 2006/07, four multivariable models were created (macro-environmental, maternal, individual, and final model) assuming hierarchy among the risk factors. In the final model, only the following remained associated with overweight: regions South/Southeast (1.55 [1.17 to 2.06]), middle-class (1.35 [1.02 to 1.77]), maternal obesity (1.66 [1.22 to 2.27]), birth weight > 3.9 kg (1.87 [1.31 to 2.67]), and being an only child or having only one sibling (1.81 [1.31 to 2.49]). CONCLUSION: the prevalence of overweight among preschool children in Brazil has increased dramatically over the past 17 years, and it was higher in the 1996-2006 period. Future strategies for prevention and control of overweight in public health should focus or intensify actions in communities that are characterized by the presence of the risks identified in the present study. .

OBJETIVO: descrever a tendência secular do excesso de peso (EP) entre pré-escolares nos anos de 1989, 1996 e 2006 e identificar os fatores de risco associados a esta condição em 2006. MÉTODOS: análise dos dados de três inquéritos antropométricos (1989, 1996 e 2006) com a mostra representativa da população brasileira. O EP foi definido como o escore-Z de peso-para-altura > + 2. Os modelos multivariáveis de associação do EP com os fatores de risco foram gerados por meio da regressão de Poisson e as estimativas apresentadas como razão de prevalência com seus respectivos intervalos de confiança de 95% (RP [IC 95%]). RESULTADOS: no período de 17 anos estudado, a prevalência relativa do EP em pré-escolares aumentou em 160% no Brasil, representando incremento de 9,4% ao ano. A partir dos dados da Pesquisa Nacional de Demografia e Saúde da Mulher e da Criança-2006/07 criamos quatro modelos multivariáveis (macroambiental, materno, individual, modelo final) assumindo hierarquia entre os fatores de risco. No modelo final, permaneceram como fatores associados ao EP: as macrorregiões Sul/Sudeste (1,55 [1,17-2,06]), a classe média (1,35 [1,02-1,77]), a obesidade materna (1,66 [1,22-2,27]), o peso ao nascer > 3,9 kg (1,87 [1,31-2,67]) e ser filho único ou possuir um irmão (1,81 [1,31-2,49]). CONCLUSÃO: a prevalência de EP entre pré-escolares no Brasil aumentou drasticamente nos últimos 17 anos, sendo mais intenso no intervalo de 1996-2006. Futuras estratégias de prevenção e controle do EP em saúde pública devem considerar em seu escopo, ou intensificar suas ações, nas coletividades que se caracterizem pela presença dos riscos identificados neste trabalho. .

Secular trends and factors associated with overweight among Brazilian preschool children: PNSN-1989, PNDS-1996, and 2006/07.

OBJECTIVE: to describe the secular trends in overweight among preschool children in the years 1989, 1996, and 2006, and to identify risk factors associated with this condition in 2006. METHODS: anthropometric data from three surveys (1989, 1996, and 2006) with a representative sample of the population were analyzed. Overweight was defined as the weight-for-height Z-score. The multivariable models of overweight association with risk factors were generated by Poisson regression, and the estimates were shown as prevalence ratios with their respective 95% confidence intervals (PR [95% CI]). RESULTS: throughout the 17-year period studied, the relative prevalence of overweight in preschoolers increased by 160% in Brazil, representing an increase of 9.4% per year. Based on data from the National Survey on Demography and Health of Women and Children - 2006/07, four multivariable models were created (macro-environmental, maternal, individual, and final model) assuming hierarchy among the risk factors. In the final model, only the following remained associated with overweight: regions South/Southeast (1.55 [1.17 to 2.06]), middle-class (1.35 [1.02 to 1.77]), maternal obesity (1.66 [1.22 to 2.27]), birth weight ≥ 3.9kg (1.87 [1.31 to 2.67]), and being an only child or having only one sibling (1.81 [1.31 to 2.49]). CONCLUSION: the prevalence of overweight among preschool children in Brazil has increased dramatically over the past 17 years, and it was higher in the 1996-2006 period. Future strategies for prevention and control of overweight in public health should focus or intensify actions in communities that are characterized by the presence of the risks identified in the present study.