Kaplan Meier survival function for the probability of first fall from a raised surface overall during the first two years of life.

FERF = First Event of Raised surface Fall.</p

Potential risk factors of the 2,886 mother‐child pairs.

Potential risk factors of the 2,886 mother‐child pairs.</p

Leading cause of unintentional injuries during the first and second year of life.

Leading cause of unintentional injuries during the first and second year of life.</p

Results of the Log-rank test.

(PDF)</p

DNA Methylome Marks of Exposure to Particulate Matter at Three Time Points in Early Life

Maternal exposure to airborne particulate matter (PM) has been associated with restricted fetal growth and reduced birthweight. Here, we performed methylome-wide analyses of cord and children’s blood DNA in relation to residential exposure to PM smaller than 10 μm (PM₁₀). This study included participants of the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC, cord blood, <i>n</i> = 780; blood at age 7, <i>n</i> = 757 and age 15–17, <i>n</i> = 850) and the EXPOsOMICS birth cohort consortium including cord blood from ENVIR<i>ON</i>AGE (<i>n</i> = 197), INMA (<i>n</i> = 84), Piccolipiù (<i>n</i> = 99) and Rhea (<i>n</i> = 75). We could not identify significant CpG sites, by meta-analyzing associations between maternal PM₁₀ exposure during pregnancy and DNA methylation in cord blood, nor by studying DNA methylation and concordant annual exposure at 7 and 15–17 years. The CpG cg21785536 was inversely associated with PM₁₀ exposure using a longitudinal model integrating the three studied age groups (−1.2% per 10 μg/m³; raw <i>p</i>-value = 3.82 × 10^–8). Pathway analyses on the corresponding genes of the 100 strongest associated CpG sites of the longitudinal model revealed enriched pathways relating to the GABAergic synapse, p53 signaling and NOTCH1. We provided evidence that residential PM₁₀ exposure in early life affects methylation of the CpG cg21785536 located on the EGF Domain Specific O-Linked <i>N</i>-Acetylglucosamine Transferase gene

Integrating clinical and epidemiological data on allergic diseases across birth cohorts: A harmonization study in the mechanisms of the development of allergy project

International collaborations among birth cohorts to better understand asthma and allergies have increased in the last years. However, differences in definitions and methods preclude direct pooling of original individual participant data. We harmonized data from 14 birth cohorts, with three to 20 follow-ups, from nine European countries, as part of the Mechanisms of the Development of Asthma and Allergies (MeDALL) project. The harmonization process followed six steps: organization of the harmonization panel; identification of variables relevant to MeDALL objectives (candidate variables); proposal of a definition for each candidate variable (reference definition); assessment of the compatibility of each cohort variable to its reference definition (inferential equivalence) and classifications of this inferential equivalence as complete, partial, or impossible; workshop to agree on the reference definitions and classifications of inferential equivalence; and data preparation and delivery through a knowledge management portal. We agreed on 137 reference definitions. The inferential equivalence of 3,551 cohort variables to their corresponding reference definition was classified as complete, partial and impossible for 70%, 15% and 15% of the variables, respectively. A harmonized database was delivered. In birth cohorts of asthma and allergies, the harmonization of data for pooled analyses is feasible and may achieve high inferential comparability. The MeDALL harmonization approach can be used in other collaborative projects