Mothers education and offspring asthma risk in 10 European cohort studies

Highly prevalent and typically beginning in childhood, asthma is a burdensome disease, yet the risk factors for this condition are not clarified. To enhance understanding, this study assessed the cohort-specific and pooled risk of maternal education on asthma in children aged 3-8 across 10 European countries. Data on 47,099 children were obtained from prospective birth cohort studies across 10 European countries. We calculated cohort-specific prevalence difference in asthma outcomes using the relative index of inequality (RII) and slope index of inequality (SII). Results from all countries were pooled using random-effects meta-analysis procedures to obtain mean RII and SII scores at the European level. Final models were adjusted for child sex, smoking during pregnancy, parity, mothers age and ethnicity. The higher the score the greater the magnitude of relative (RII, reference 1) and absolute (SII, reference 0) inequity. The pooled RII estimate for asthma risk across all cohorts was 1.46 (95% CI 1.26, 1.71) and the pooled SII estimate was 1.90 (95% CI 0.26, 3.54). Of the countries examined, France, the United Kingdom and the Netherlands had the highest prevalences of childhood asthma and the largest inequity in asthma risk. Smaller inverse associations were noted for all other countries except Italy, which presented contradictory scores, but with small effect sizes. Tests for heterogeneity yielded significant results for SII scores. Overall, offspring of mothers with a low level of education had an increased relative and absolute risk of asthma compared to offspring of high-educated mothers.

Funding Agencies|European Unions Seventh Framework Programme as part of The Determinants to Reduce Health Inequity Via Early Childhood, Realising Fair Employment [278350]; Social Protection (DRIVERS) research programme; Ministry of Education of the Czech Republic: CETOCOEN plus project [CZ02101/00/00/15_003/0000469]; RECETOX Research Infrastructure [LM2015051]; Academy of Finland [FI-NFBC8586]; Biocenter, University of Oulu, Finland; European Commission EUROBLCS, Framework 5 Award [QLG1-CT-2000-01643]; EU [FP7 EurHEALTHAgeing-277849]; Medical Research Council, UK (PrevMetSyn/SALVE); MRC Centenary Early Career Award; Netherlands Organization for Health Research and Development (ZonMw) Grant (TOP) [40-00812-98-11010]; Juvenile Diabetes Research Foundation; Swedish Child Diabetes Foundation (Barndiabetesfonden); Research Council of South-east Sweden (FORSS); Swedish Research Council [K2005-72X-11242-11A]; ALF/County Council of Ostergotland; European Union, Spain (Instituto de Salud Carlos III) [FP7-ENV-2011-282957, HEALTH. 2010.2.4.5-1]; European Union, Spain (Ministry of Health) [FP7-ENV-2011-282957, HEALTH. 2010.2.4.5-1]; Conselleria de Sanitat of the Generalitat Valenciana; Department of Health of the Basque Government; Provincial Government of Gipuzkoa; Generalitat de Catalunya-CIRIT; US NIH Fogarty International Center; National Academy of Medical Sciences of Ukraine; Medical Research Council UK doctoral training studentship