Maternal exposure to air pollutants, PCSK9 levels, fetal growth and gestational age - An Italian cohort

Abstract

Objective: Exposure to airborne pollutants during pregnancy appears to be associated with uterine growth restriction and adverse neonatal outcome. Proprotein convertase subtilisin/kexin type (PCSK9), the key modulator of low-density lipoprotein (LDL) metabolism, increases following particulate matter (PM₁₀) exposure. Because maternal cholesterol is required for fetal growth, PCSK9 levels could be used to evaluate the potential impact of airborne pollutants on fetal growth.

Design: A cohort of 134 healthy women during early pregnancy (11-12 weeks of gestational age) was studied.

Results: A significant association between circulating PCSK9 levels and three tested air pollutants (PM₁₀, PM_2.5, nitric oxide (NO₂)) was found. Of importance, gestational age at birth was reduced by approximately 1 week for each 100 ng/mL rise in circulating PCSK9 levels, an effect that became more significant at the highest quartile of PM_2.5 (with a 1.8 week advance in delivery date for every 100 ng/mL rise in circulating PCSK9; p for interaction = 0.026). This finding was supported by an elevation of the odds ratio for urgent cesarean delivery for each 100 ng/mL rise in PCSK9 (2.99, 95% CI, 1.22-6.57), similar trends being obtained for PM₁₀ and NO₂.

Conclusions: The association between exposure to air pollutants during pregnancy and elevation in PCSK9 advances our understanding of the unforeseen influences of environmental exposure in terms of pregnancy associated disorders.

Keywords: Air pollutants; Fetal growth; Gestational age; PCSK9; Particulate matter (PM(10) and PM(2.5)).