The Predictive Value of Red Blood Cell Distribution Width on Hypertensive Disorders of Pregnancy: A STROBE-Compliant Propensity Score-Matching Study

Background: Red blood cell distribution width (RDW) is associated with inflammation and oxidative stress. This study investigated the predictive value of RDW for hypertensive disorders of pregnancy (HDP). Methods: This retrospective cohort study, using propensity score matching (PSM), included 1546 women admitted to the West China Second University Hospital between January 2021 and January 2022. Univariate logistic regression analysis was performed on variables that remained unbalanced after PSM. Receiver operating characteristic (ROC) curves were used to assess the predictive ability of RDW for HDP. Results: Following a 1:1 PSM, the analysis enrolled two cohorts: a simple hypertension group (n = 420) with a matched control group (n = 420), and a preeclampsia group (n = 353) and a matched control group (n = 353). Univariate logistic regression analysis revealed no significant association between RDW and simple hypertension (gestational or chronic); however, a significant correlation was observed between RDW and preeclampsia. ROC curve analysis demonstrated that the coefficient of variation of RDW predicted severe preeclampsia with 72% diagnostic accuracy, with a cutoff value of ≥14.65% and area under the curve (AUC) of 0.696. Additionally, the RDW standard deviation (RDWSD) predicted severe preeclampsia with 76% diagnostic accuracy, with a cutoff value of ≥51.85 fL and AUC of 0.661. Conclusions: Although RDW is a significant independent predictor of preeclampsia, its diagnostic performance is moderate. Due to its speed, low cost, and wide availability, RDW is best utilized as an auxiliary component in combinatorial risk models or multi-marker panels, augmenting established predictors.