Early life multiple exposures and child cognitive function: A multi-centric birth cohort study in six European countries

Abstract

Epidemiological studies mostly focus on single environmental exposures. This study aims to systematically assess associations between a wide range of prenatal and childhood environmental exposures and cognition. The study sample included data of 1298 mother-child pairs, children were 6–11 years-old, from six European birth cohorts. We measured 87 exposures during pregnancy and 122 cross-sectionally during childhood, including air pollution, built environment, meteorology, natural spaces, traffic, noise, chemicals and life styles. The measured cognitive domains were fluid intelligence (Raven's Coloured Progressive Matrices test, CPM), attention (Attention Network Test, ANT) and working memory (N-Back task). We used two statistical approaches to assess associations between exposure and child cognition: the exposome-wide association study (ExWAS) considering each exposure independently, and the deletion-substitution-addition algorithm (DSA) considering all exposures simultaneously to build a final multiexposure model. Based on this multiexposure model that included the exposure variables selected by ExWAS and DSA models, child organic food intake was associated with higher fluid intelligence (CPM) scores (beta = 1.18; 95% CI = 0.50, 1.87) and higher working memory (N-Back) scores (0.23; 0.05, 0.41), and child fast food intake (−1.25; −2.10, −0.40), house crowding (−0.39; −0.62, −0.16), and child environmental tobacco smoke (ETS) (−0.89; −1.42, −0.35), were all associated with lower CPM scores. Indoor PM 2.5 exposure was associated with lower N-Back scores (−0.09; −0.16, −0.02). Additional associations in the unexpected direction were found: Higher prenatal mercury levels, maternal alcohol consumption and child higher perfluorooctane sulfonic acid (PFOS) levels were associated with better cognitive performance; and higher green exposure during pregnancy with lower cognitive performance. This first comprehensive and systematic study of many prenatal and childhood environmental risk factors suggests that unfavourable child nutrition, family crowdedness and child indoor air pollution and ETS exposures adversely and cross-sectionally associate with cognitive function. Unexpected associations were also observed and maybe due to confounding and reverse causality.

Association between the Use of Folic Acid Supplements during Pregnancy and Children’s Cognitive Function at 7–9 Years of Age in the INMA Cohort Study

“…We have no explanation for this unexpected finding, although this is not the first time that a protective effect on children's cognitive function of an apparently harmful exposure during pregnancy has been described in the scientific literature. A multicentric birth cohort study in six European countries has associated higher prenatal mercury levels and maternal alcohol consumption, two harmful exposures, during pregnancy with better cognitive performance in children at 6-11 y [70]. Similarly, another study has shown that higher organochlorine prenatal exposure can increase attentional function (i.e., the hit reaction time) in girls at age 8 [71].…”

Associations of four biological age markers with child development: A multi-omic analysis in the European HELIX cohort

“…Trained fieldwork technicians measured three cognitive domains in children using a battery of computer-based tests: fluid intelligence (Raven Coloured Progressive Matrices Test [CPM]), attention function (Attention Network Test [ANT]) and working memory (N-Back task). Complete outcome descriptions are provided in [86]. The CPM comprised a total of 36 items and we used the total number of correct responses as the outcome.…”

“…and working memory (N-Back task). Complete outcome descriptions are provided in [86]. The CPM comprised a total of 36 items and we used the total number of correct responses as the outcome.…”

“…The proportion of fat mass was calculated using published age-and race-specific equations validated for use in children [85]. [86]. The CPM comprised a total of 36 items and we used the total number of correct responses as the outcome.…”

Using an Exposome-Wide Approach to Explore the Impact of Urban Environments on Blood Pressure among Adults in Beijing–Tianjin–Hebei and Surrounding Areas of China

“…Accordingly, the exposome approach may help identify determinants of unfavorable BP more scientifically and develop prevention priorities. Furthermore, such an exposome method has achieved its recent application in systematically assessing urban environmental exposures and numerous child health outcomes in Europe, ,− including one study that specifically focused on BP in children, which identified several relevant environmental exposures (e.g., air pollution) . However, none studies have analyzed the impact of urban environment on BP in adults using such an exposome approach.…”