Absence of enhanced systemic inflammatory response at 18 weeks of gestation in women with subsequent pre-eclampsia

Abstract

Objective: To compare indicators of systemic inflammatory response in the second trimester in women who developed pre-eclampsia with normal pregnancies. Design: Prospective nested case control study derived from a cohort of 2190 pregnant women. Blood samples were obtained at 18 weeks of gestation. The following inflammatory parameters were measured: tumour necrosis factor-α (TNF-α), plasminogen activator inhibitor-1 (PAI-1), interleukin-1β (IL-1β), IL-6, IL-10, microCRP and tissue factor (TF). Setting: Institute of Medical Genetics, University of Oslo, and Department of Medical Genetics, Ullevål University Hospital and Departments of Obstetrics and Gynecology, Aker University Hospital, Oslo, Norway. Sample: The cases were 71 women who subsequently developed pre-eclampsia. The controls were 71 healthy, pregnant women matched for age, parity and first trimester body mass index (BMI). Methods: Venous blood was drawn from fasting subjects into 5 mL test tubes containing EDTA. Samples were analysed for inflammatory parameters: IL-1-β, IL-6, IL-10, TNF-α, PAI-1, TF (ELISA-technique) and CRP (latex-enhanced immunonephelometric assay), strictly according to the manufacturer's recommendation. Main outcome measures: The matched case and control subjects were compared by the paired two-tailed Wilcoxon signed rank test. All P values were two-tailed and P < 0.05 was deemed statistically significant. Results: We found no differences in plasma concentrations of PAI-1, IL-1β, IL-6, IL-10, microCRP, TNF-α or TF at 18 weeks of gestation between women who subsequently developed pre-eclampsia and matched control women. Conclusion: In contrast to findings from women with overt pre-eclampsia, the present study indicates that there are no indications of intensified systemic inflammatory response at 18 weeks of gestation in women who later develop pre-eclampsia.