Plasma Levels of the Cerebral Biomarker, Neuron-Specific Enolase, are Elevated During Pregnancy in Women Developing Preeclampsia

Objectives: Neuron-specific enolase (NSE) is considered to be a peripheral biomarker of central nervous system injury. The aim of this study was to compare levels of NSE throughout pregnancy, in healthy pregnant women and in women developing preeclampsia. Methods: A nested case-control study within a longitudinal study cohort was performed. Four hundred sixty nine healthy pregnant women were enrolled, and plasma samples were collected at gestational weeks 10, 25, 28, 33, and 37. Levels of NSE were analyzed in 16 women with preeclampsia and 36 controls throughout pregnancy with an enzyme-linked immunosorbent assay. Results: In gestational week 37, women who developed preeclampsia had significantly higher plasma levels of NSE than healthy pregnant controls (P < .001). The levels of NSE did not change between gestational weeks 10 and 37 in women who developed preeclampsia, but the levels decreased significantly in healthy pregnant controls (P < .001). Conclusion: In pregnant women developing preeclampsia, the levels of NSE remained high throughout pregnancy, whereas in healthy women, these tended to decline over time, especially at the 2 last time points. The result might be confounded in early pregnancy by extracerebral sources of NSE, such as the corpus luteum. Findings need to be confirmed in a larger prospective study.