Modulating effects of maternal fish consumption on the occurrence of respiratory symptoms in early infancy attributed to prenatal exposure to fine particles

Abstract

The purpose of the study was to test the hypothesis whether infants with higher prenatal exposure to fine particles (PM(2.5)) are at greater risk of developing respiratory symptoms and whether fish consumption in pregnancy may modulate the effect. The study was carried out in a cohort of 465 newborns in Krakow (Poland) who have been followed over the first 2 years of life and for whom data on the occurrence of respiratory symptoms and measurements of personal air monitoring in the second trimester of pregnancy were available. The incidence risk ratio (IRR) of respiratory symptoms due to prenatal PM(2.5) exposure were adjusted for potential confounders (gender of child, breastfeeding, parity, maternal atopy, maternal education as a proxy for the socio-economic status, exposure to postnatal environmental tobacco smoke (ETS), and moulds in households) in the generalized estimating equations (GEE) statistical models. The adjusted risk of coughing was associated significantly with PM(2.5) level (IRR = 2.51; 95% CI: 1.77-3.58), moulds in the household, parity, maternal atopy and postnatal ETS, but was lower in girls, and in infants whose mothers consumed more fish in pregnancy (IRR = 0.85; 95% CI: 0.79-0.91). The risk of wheezing was also correlated significantly with the prenatal exposure to PM(2.5) (IRR = 1.36; 95% CI: 1.29-1.43) but also with the presence of moulds in homes, parity, maternal atopy and postnatal ETS. The occurrence of wheezing was associated inversely with the gender of child, gestational age, and fish consumption in pregnancy (IRR = 0.97; 95% CI: 0.95-0.99). Similarly, the risk of difficult (puffy) breathing increased with prenatal exposure to PM(2.5) (IRR = 1.18; 95% CI: 1.12-1.25) moulds, maternal atopy, and parity. The symptom occurrence was lower in girls and associated inversely with the gestational age, and fish consumption in pregnancy (IRR = 0.94; 95% CI: 0.92-0.97). The results of the study support the hypothesis that fish consumption in pregnancy may mitigate the harmful effect of prenatal or perinatal exposure to components of PM(2.5) resulting in an increased burden of respiratory infections among infants.