Body Mass Index Development from Birth to Early Adolescence; Effect of Perinatal Characteristics and Maternal Migration Background in a Swedish Cohort

<div><p>Background</p><p>Well documented diversity in risk of developing overweight and obesity between children of immigrant and of native mothers, might be explained by different body mass index (BMI) development trajectories in relation to maternal and perinatal characteristics of offspring.</p><p>Objectives</p><p>To assess BMI development trajectories among children born to immigrant and to Swedish mothers from birth to adolescence in relation to perinatal characteristics.</p><p>Methods</p><p>A cohort of 2517 children born in Stockholm during 1994 to 1996 was followed with repeated measurement of height and weight at eleven time points until age 12 years. We estimated changes over time for BMI in relation to maternal and perinatal characteristics of offspring using mixed linear model analysis for repeated measure data.</p><p>Results</p><p>We observed a significant BMI change over time in children and time interaction with maternal migration status (<i>P</i><0.0001). Estimated BMI over time adjusted for maternal and perinatal characteristics of offspring, showed slower BMI growth before age of 5, followed by an earlier plateau and steeper BMI growth after 5 years among children of immigrant mothers compared with children of Swedish mothers. These differences in BMI growth were more prominent among children with mothers from outside Europe.</p><p>Conclusion</p><p>Beside reinforcing early childhood as a crucial period in development of overweight, the observed slower BMI development at early childhood among children of immigrants followed by a steeper increase in BMI compared with children of Swedish mothers is important for further studies and for planning of preventive public health programs.</p></div

Estimated body mass index (BMI) from birth to 12 years, adjusted for maternal and perinatal characteristics by maternal migration status in girls (A) and boys (B) born between 1994 and 1996 in Stockholm.

<p>* Circles represent crude mean BMI.</p

Maternal and perinatal characteristics of the study population, children born between 1994 and 1996 in Stockholm by maternal migration status.

<p>Bolded numbers are statistically significant Comparing immigrant with counterpart Swedish mothers (T-test or chi-square for continuous or categorical variables): * p<0.05, ** p<0.01, *** p<0.001.</p><p>Bolded numbers are statistically significant.</p>1<p>Standard deviation.</p>2<p>Body mass index.</p>3<p>Smoking during pregnancy.</p>4<p>Low BW = BW<2500 gram; High BW =  BW≥4000 gram; Normal BW =  2500≤BW<4000 gram.</p>5<p>Preterm =  delivery<38 weeks; Post term =  delivery> 42 weeks; Term =  delivery between 38–42 weeks of gestation.</p>6<p>SGA = small for gestational age; LGA =  large for gestational age; AGA =  appropriate for gestational age.</p><p>Maternal and perinatal characteristics of the study population, children born between 1994 and 1996 in Stockholm by maternal migration status.</p

Association between maternal and perinatal characteristics and body mass index (BMI) from birth to 12 years of age in the study population, children born between 1994 and 1996 in Stockholm, using conditional mixed model.

<p>Bold numbers are statistically significant</p>1<p>Age at first antenatal clinic visit, almost around week 12−14 of gestation</p>2<p>Smoking at least one cigarette per day, at any time during pregnancy</p>3<p>Diabetes, preeclampsia and eclampsia, hypertension, anemia, renal disease, liver disease and placental disorders which might affect fetal growth</p>4<p>Total breast feeding: number of months that child has been breastfed, both exclusive and partial</p>5<p>AGA =  appropriate for gestational age</p>6<p>SGA =  small for gestational age</p>7<p>LGA =  large for gestational age</p>8<p>Time variable in this model is ‘Age’ (year) at weight and height measurement in children. Since the changes in BMI at different ages is not linear or a straight line, different polynomial functions of ‘Age’ has been used to take into account non-linear changes in BMI in different ages. Then, ‘Age’ accounts for linear changes, ‘Age*Age’ accounts for unidirectional curvilinear changes, ‘Age*Age*Age’ accounts for bi-directional curvilinear changes and ‘Age-log’ account for sharp changes, either peak or bottom.</p><p>Association between maternal and perinatal characteristics and body mass index (BMI) from birth to 12 years of age in the study population, children born between 1994 and 1996 in Stockholm, using conditional mixed model.</p

Estimated body mass index (BMI) from birth to 12 years, adjusted for maternal and perinatal characteristics by subgroups of maternal migration status in girls (A) and boys (B) born between 1994 and 1996 in Stockholm.

<p>Estimated body mass index (BMI) from birth to 12 years, adjusted for maternal and perinatal characteristics by subgroups of maternal migration status in girls (A) and boys (B) born between 1994 and 1996 in Stockholm.</p

Additional file 1: Tables S1-S10. of The emerging landscape of dynamic DNA methylation in early childhood

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Additional file 2: Figures S1-S7. of The emerging landscape of dynamic DNA methylation in early childhood

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Additional file 5: of The emerging landscape of dynamic DNA methylation in early childhood

List of age differential Methylation Quantitative Trait Locus in early childhood (XLSX 336 kb

Allergic rhinitis.

<p>Meta-analyses of the adjusted odds of <b>allergic rhinitis</b> (sensitized to at least 1 aero-allergen; secondary endpoint) in early school age and pet ownership in the first 2 years of life for: A), cat only vs. no pets; B), dog only vs. no pets; C) cat and dog only vs. no pets; D) bird only vs. no pets; E) rodents only vs. no pets.</p

Prevalence of current asthma, allergic asthma (sensitized to ≥1 aero-allergen), allergic rhinitis (sensitized to ≥1 aero-allergen) and allergic sensitization (≥1 aero-allergen >0.35 kU/L) at last follow-up assessment between 6 to 10 years in 11 European birth cohorts.

<p>n.a. = not assessed.</p>1<p>in DARC, AMICS-Barcelona and AMICS-Menorca, sensitization data were only available for the age of 4 years.</p