Prevalence and maternal determinants of early and late introduction of complementary foods: results from the Growing Up in New Zealand cohort study.

A nationally generalisable cohort (n 5770) was used to determine the prevalence of non-timely (early/late) introduction of complementary food and core food groups and associations with maternal sociodemographic and health behaviours in New Zealand (NZ). Variables describing maternal characteristics and infant food introduction were sourced, respectively, from interviews completed antenatally and during late infancy. The NZ Infant Feeding Guidelines were used to define early (≤ 4 months) and late (≥ 7 months) introduction. Associations were examined using multivariable multinomial regression, presented as adjusted relative risk ratios and 95 % confidence intervals (RRR; 95% CI). Complementary food introduction was early for 40·2 % and late for 3·2 %. The prevalence of early food group introduction were fruit/vegetables (23·8 %), breads/cereals (36·3 %), iron-rich foods (34·1 %) and of late were meat/meat alternatives (45·9 %), dairy products (46·2 %) and fruits/vegetables (9·9 %). Compared with infants with timely food introduction, risk of early food introduction was increased for infants: breastfed < 6months (2·52; 2·19-2·90), whose mothers were < 30 years old (1·69; 1·46-1·94), had a diploma/trade certificate v. tertiary education (1·39; 1·1-1·70), of Maori v. European ethnicity (1·40; 1·12-1·75) or smoked during pregnancy (1·88; 1·44-2·46). Risk of late food introduction decreased for infants breastfed < 6 months (0·47; 0.27-0·80) and increased for infants whose mothers had secondary v. tertiary education (2·04; 1·16-3·60) were of Asian v. European ethnicity (2·22; 1·35, 3·63) or did not attend childbirth preparation classes (2·23; 1·24-4·01). Non-timely food introduction, specifically early food introduction, is prevalent in NZ. Interventions to improve food introduction timeliness should be ethnic-specific and support longer breast-feeding.

Prevalência e fatores maternos associados à introdução não oportuna da alimentação complementar na coorte de nascimento neozelandesa Growing Up in New Zealand / Prevalence and maternal factors associated with no timely introduction of complementary feeding within the New Zealand birth cohort Growing Up in New Zealand

INTRODUÇÃO: Os primeiros 1000 dias de vida, da concepção até os dois anos de idade, são críticos para a saúde da criança. A introdução não oportuna (precoce ou tardia) dos alimentos está associada à infecções do trato gastrointestinal e respiratório, deficiência de ferro, obesidade e alergia alimentar. A Nova Zelândia não possui informações nacionalmente generalizáveis sobre a tempo de introdução dos alimentos e os determinantes sociodemográficos da introdução não oportuna dos alimentos. OBJETIVOS: i) Investigar a idade de introdução da alimentação complementar e de grupos alimentantes recomendados na coorte Growing Up in New Zealand-GUiNZ; ii) Investigar os fatores maternos e infantis associados à introdução precoce e tardia destes alimentos. MATERIAIS E MÉTODOS: O estudo GUiNZ é uma coorte de nascimento neozelandesa que acompanha quase 7000 crianças. As informações maternas sociodemográficas e de estilo de vida foram coletadas na entrevista antenatal e os informações infantis nas entrevistas de seis semanas, nove e 31 meses. Alimento complementar foi considerado qualquer alimento diferente de leite materno ou fórmula infantil ofertados para as crianças. A prevalência de introdução precoce, oportuna e tardia dos alimentos foi determinada de acordo com as recomendações do Ministério da Saúde da Nova Zelândia e da Organização Mundial da Saúde (geral e de acordo com o sexo e a duração do aleitamento materno total). Associação entre os fatores maternos e infantis e a introdução precoce e tardia dos alimentos foi investigada usando modelos múltiplos de regressão multinominal. Modelos múltiplos de regressão de Poisson com variância robusta foram utilizados para investigar os fatores maternos e infantis associados à introdução de guloseimas e bebidas açucaradas até a entrevista de 9 meses (sim/não). RESULTADOS: Dentre as 5770 crianças incluídas neste estudo, a alimentação complementar foi introduzida precocemente (<=4 meses) para 40% e tardiamente (>= 7 meses) para 3,2%. Os grupos "frutas e vegetais", "pães e cereais" e "alimentos ricos em ferro" foram introduzidos precocemente para 24%, 36% e 34% das crianças, respectivamente. O grupo "carnes e alternativas", que inclui alimentos ricos em proteínas de origem animal e vegetal e o grupo "laticínios" foram introduzidos tardiamente (>=7 meses) para 46% das crianças. A prevalência de introdução de guloseimas e bebidas açucaradas até a entrevista de nove meses foi de 52% e 38%, respectivamente. Mães que amamentaram por menor de 6 meses e/ou nunca amamentaram, com menos de 30 anos de idade, de etnia maori, com menor escolaridade, com IMC prégestacional elevado, que não planejaram a gravidez, que não frequentaram os cursos de maternidade e fumaram antes e/ou durante a gestação tiveram maior risco de introduzir os alimentos precocemente (em comparação às mães que introduziram oportunamente). Mães que amamentaram por menos de 6 meses, não frequentaram os cursos de maternidade, de etnia maori, pacífica ou asiática e com menor escolaridade apresentaram maior risco de introduzir os alimentos tardiamente (em comparação às mães que introduziram oportunamente). CONCLUSÃO: A prevalência de introdução não oportuna na coorte foi elevada e apresentou inequidade étnica, demográfica e socioeconômica nas taxas de introdução não oportuna da alimentação complementar.

INTRODUCTION: The first 1000 days of life, from conception to two years age, are critical to the infant's health. Non-timely introduction of foods (early or late) is associated with infections of the gastrointestinal and respiratory tracts, iron deficiency, obesity and food allergies. New Zealand lacks nationally generalizable information on timing of food introduction and the sociodemographic determinants of non-timely introduction of complementary feeding. OBJECTIVES: i) To investigate the age of introduction of complementary feeding and of recommended food groups within the Growing Up in New Zealand - GUiNZ cohort and; ii) To examine the maternal and infant factors associated with early and late introduction of these foods. METHODS: The GUiNZ study is a New Zealand birth cohort which follows nearly 7000 children. Maternal sociodemographic and lifestyle information was collected in the antenatal interview and infant's information was prevenient from the six-week, nine and 31-month interviews. It was considered as complementary food any food item other than breast milk or infant formula that was introduced to babies. Prevalence of early, timely and late age of food introduction were evaluated according to the recommendations of the New Zealand Ministry of Health and the World Health Organization (overall and according to sex and breastfeeding duration). Associations between maternal and infant factors with early and late introduction of foods were examined using multivariate multinomial regressions. Multivariate Poisson regressions with robust variance were performed to examine maternal and infant factors associated with the introduction of snacks and sugary drinks up until the 9-month interview (yes/no). RESULTS: Among the 5770 children included in this study, complementary feeding was introduced early (<=4th month) to 40% and late (>=7th month) to 3,2%. The groups "fruits and vegetables", "breads and cereals" and "iron rich foods" were early introduced to 24%, 36% and 34% of the infants, respectively. "Meat and alternatives", which includes foods rich in protein from animal and vegetable sources, and products from the "dairy" group were introduced late to 46% of the infants. The prevalence of introduction of 'snacks' and 'sugary drinks' by the time of the 9- month interview were 52% and 38%, respectively. Mothers who breastfed for less than 6 months and/or never breastfed, who were younger than 30 years old, who were from Maori ethnicity, who had high pre-pregnancy BMI, who had unplanned pregnancy, who did not attend to maternity preparation classes and who smoked before and/or during pregnancy were more likely to introduce their babies foods earlier (in relation to mothers of babies who were timely introduced). Mothers who breastfed for less than 6 months, who did not attend to maternity preparation classes, who were from Maori, Pacific or Asian ethnicities and who had lower level of formal education were more likely to introduce their babies foods late (in relation to mothers of babies who were timely introduced). CONCLUSION: The prevalence of non-timely food introduction within the cohort was high and there were ethnic, demographic and socioeconomic inequities in the rates of non-timely introduction of complementary feeding.