Work

Associations between oxidative stress and inflammation and preterm birth in Puerto Rico

Year: 2019

Type: article

Abstract: TPS 723: Low and middle income countries: sanitation infections and other health effects, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background/Aim: Preterm birth (PTB; gestational age <37 weeks) is the leading cause of infant morbidity and mortality worldwide. Oxidative stress and inflammation have been implicated as contributors to PTB; however, these pathways are difficult to distinguish in human populations. Using data from the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) cohort (N=469), we examined associations between urinary 8-iso-prostaglandin F2α (8-iso-PGF2α) concentrations and PTB, and applied a novel approach to identify whether the association was attributable to oxidative stress or inflammation. Methods: 8-iso-prostaglandin F2α (8-iso-PGF2α) and prostaglandin F2α (PGF2α) were measured in urine samples collected at up to 3 timepoints across pregnancy (median 18, 24, 28 weeks gestation) and averaged. Logistic regression models were used to calculate adjusted odds ratios (OR) for the associations between average concentrations and PTB. We quantified the proportion of 8-iso-PGF2α originating from oxidative stress and inflammation pathways with a formula based on the ratio of 8-iso-PGF2α to PGF2α. Finally, we examined associations between 8-iso-PGF2α fractions and PTB. Results: The geometric means of 8-iso-PGF2α and PGF2α were higher among women who delivered preterm compared to term. An interquartile range (IQR) difference in 8-iso-PGF2α was associated with increased odds of PTB (OR=1.64, 95% confidence interval [CI] =1.07-2.54). This association appeared to be driven by associations with inflammation. An IQR increase in the fraction of 8-iso-PGF2α derived from inflammation was associated with PTB (OR=1.56, 95% CI=1.01, 2.53), the fraction of 8-iso-PGF2α derived from oxidative stress was not associated with PTB (OR=1.05, 95% CI=0.72, 1.54). Conclusions: Our results indicate an association between 8-iso-PGF2α, a traditional oxidative stress biomarker, and PTB. Our additional interrogation of that association indicates that the relationship is likely attributable to elevated inflammation. Further research is needed to improve our understanding of the role these biomarkers may play in the causal pathway between environmental factors and PTB.

Source: Environmental Epidemiology

DOI: 10.1097/01.ee9.0000606904.69736.50

Authors: Eick S, Ferguson K, Milne G, Alshawabkeh A, Cordero J, Meeker J