Association and interaction between metal aluminum and iron exposure and the risk of offspring’ congenital heart defects in northwestern China

Abstract

Abstract Congenital heart disease (CHDs) is the leading cause of mortality from birth defects, affecting up to 1% of live births. However, there have been inconsistent results of the relationship between aluminum (Al) /iron (Fe) level and risk of CHDs. We performed a pair-matched case–control study and included 97 cases and 194 controls to investigate the association and interaction between Al/Fe exposure and the risk of CHDs in a birth cohort study conducted in Lanzhou, China. Compared to < 25th percentile of Al in CB, risk differences were significantly detected in > 75th percentile of Al in total CHDs (aOR = 2.826, 95% CI: 1.009–7.266) and isolated CHDs (aOR = 10.713, 95% CI: 1.017–112.851). Although a similar pattern was not detected in MB of Al and Fe in both MB and CB, a significant dose-effect was observed between the Al level and total CHDs in both MB and CB (Ptrend < 0.05). Compared to both lowest tertile of Al and Fe level in umbilical cord blood, the highest tertile was associated with an increased risk of CHDs, especially for multiple CHDs, septal defects and patent ductus arteriosus. Overall, our study suggests a significant association between pregnancy Al exposure (≥ 2.408 mg/L) and risk of CHDs, especially for septal defects, and high Al and Fe elicited a strong correlation on fetal heart development. Future studies are needed to elucidate the underlying mechanism.