Associations of maternal education, area deprivation, proximity to greenspace during pregnancy and gestational diabetes with Body Mass Index from early childhood to early adulthood: A proof-of-concept federated analysis in seventeen birth cohorts
Authors: Cadman Tim , Elhakeem Ahmed , Vinther Johan Lerbech , Avraam Demetris , Espi Paula Carrasco , Calas Lucinda , Cardol Marloes , Charles Marie-Aline , Corpeleijn Eva , Crozier Sarah , de Castro Montserrat , Estarlich Marisa , Fernandes Amanda , Fossatti Serena , Gruszfeld Dariusz , Gurlich Kathrin , Grote Veit , Haakma Sido , Harris Jennifer R. , Heude Barbara , Huang Rae-Chi , Ibarluzea Jesús , Inskip Hazel , Jaddoe Vincent , Koletzko Berthold , Lioret Sandrine , Luque Veronica , Manios Yannis , Moirano Giovenale , Moschonis George , Nader Johanna , Nieuwenhuijsen Mark , Nybo-Andersen Anne-Marie , McEachen Rosmary , de Moira Angela Pinot , Popovic Maja , Salika Theodosia , Roumeliotaki Theano , Marina Loreto Santa , Santos Susana , Serbert Sylvain , Tzorovili Evangelia , Vafeiadi Marina , Verduci Elvira , Vrijheid Martine , Welten Marieke , Wright John , Yang Tiffany C , Zugna Daniela , Lawlor Deborah 
Published: July 2022

Background

International sharing of cohort data for research is important and challenging. The LifeCycle project aimed to harmonise data across birth cohorts and develop methods for efficient federated analyses of early life stressors on offspring outcomes.

Aim

To explore feasibility of federated analyses of associations between four different types of pregnancy exposures (maternal education, area deprivation, proximity to green space and gestational diabetes) with offspring BMI from infancy to 17 years.

Methods

We used harmonised exposure and outcome data from 17 cohorts (n=200,650 mother-child pairs) from the EU Child Cohort Network. For each child, we derived BMI at five age periods: (i) 0-1 years, (ii) 2-3, (iii) 4-7, (iv) 8-13 and (v) 14-17 years. Associations were estimated using linear regression via one-stage individual participant data meta-analysis using the federated analysis platform DataSHIELD.

Results

Associations between lower maternal education and higher child BMI emerged from age 4 years and increased with age (difference in BMI z-score comparing low with high education age 0-1 years = 0.02 [95% CI 0.00, 0.03], 2-3 years = 0.01 [CI -0.02, 0.04], 4-7 years = 0.14 [CI 0.13, 0.16], 8-13 years = 0.22 [CI 0.20, 0.24], 14-17 years = 0.20 [CI 0.16, 0.23]). A similar pattern was found for area deprivation. Gestational diabetes was positively associated with BMI from 8 years (8-13 years = 0.17 [CI 0.10, 0.24], 14-17 years = 0.012 [CI -0.13, 0.38]) but not at younger ages. The normalised difference vegetation index measure of maternal proximity to green space was weakly associated with higher BMI in the first year of life but not at older ages.

Conclusions

Associations between maternal education, area-based socioeconomic position and GDM with BMI increased with age. Maternal proximity to green space was not associated with offspring BMI, other than a weak association in infancy. Opportunities and challenges of cross-cohort federated analyses are discussed.