(239) Does the definition of significant proteinuria matter? A retrospective cohort study

Objective: Preeclampsia poses significant risks to maternal and perinatal health, with proteinuria serving as a key diagnostic criterion. However, the optimal definition of significant proteinuria remains uncertain, prompting this study to compare the impact of two definitions—based on concentration ( >300 mg per liter per 24 hours) or per volume ( >300 mg per 24 hours)—on maternal and perinatal outcomes in patients diagnosed with preeclampsia. This retrospective cohort study aimed to assess the influence of these two different definitions of significant proteinuria on maternal and perinatal outcomes in patients with preeclampsia.

Study Design: Medical records-based registry data from a teaching hospital in northeast Florida were collected during two distinct periods: March 2007 to November 2010 and January 2017 to December 2022. Pregnant patients diagnosed with preeclampsia were divided into two groups based on two definitions of significant proteinuria. Data analysis compared baseline characteristics, maternal outcomes, and neonatal outcomes.

Results: A total of 242 pregnancies were included in the analysis. Patients with proteinuria of >300 mg per liter per 24 hours were more likely to have severe preeclampsia, elevated systolic blood pressure, require intravenous antihypertensive treatment, undergo cesarean delivery, exhibit abnormal biochemical tests, and deliver at an earlier gestational age compared to patients with proteinuria of >300 mg per 24 hours.

Conclusion: In this study, the concentration-based definition of significant proteinuria in preeclampsia was associated with worse neonatal and maternal outcomes. These findings suggest that the amount of proteinuria may help stratify risk among pregnant patients. However, further research is needed to corroborate these findings and to refine the diagnostic criteria for preeclampsia to enhance management protocols and improve patient care.