# Second-Trimester Fibrinogen-to-Albumin Ratio and Platelet Activation Markers Compared with the HALP Score for Predicting Preeclampsia

## TL;DR

This study compares blood markers like fibrinogen-to-albumin ratio and platelet activation indicators to predict preeclampsia during pregnancy.

## Contribution

The study introduces the fibrinogen-to-albumin ratio (FAR) as a novel predictor of preeclampsia with better performance than the HALP score when combined with platelet distribution width.

## Key findings

- Women with preeclampsia had lower hemoglobin, hematocrit, and albumin levels compared to controls.
- The fibrinogen-to-albumin ratio (FAR) showed better discrimination for preeclampsia than the HALP score.
- Combining FAR with platelet distribution width (PDW) improved predictive accuracy (AUC 0.820).

## Abstract

Objective: This study aimed to evaluate the predictive value of second-trimester hemoglobin levels, the hemoglobin–albumin–lymphocyte–platelet (HALP) index, the fibrinogen-to-albumin ratio (FAR), and selected coagulation and platelet activation markers for the development of preeclampsia. Methods: This retrospective cohort study included 262 pregnant women, comprising 131 women who developed preeclampsia and 131 normotensive controls, followed at a tertiary referral center between 2022 and 2023. Maternal demographic, clinical, and laboratory data were obtained from routine second-trimester (14–28 weeks) antenatal assessments. HALP and FAR were calculated using standardized formulas. Group comparisons were performed using appropriate parametric or nonparametric tests. Discriminative performance was assessed using receiver operating characteristic (ROC) curve analysis with bootstrap resampling. Univariate and multivariable logistic regression models were constructed to evaluate independent associations, and combined biomarker models were compared using DeLong’s test. Results: Women with preeclampsia demonstrated significantly lower hemoglobin, hematocrit, platelet count, and albumin levels, alongside higher fibrinogen, D-dimer, LDH, CRP, and platelet activation indices (MPV, PDW, and P-LCR) (all p < 0.05). Both HALP and FAR were significantly higher in the preeclampsia group; however, FAR exhibited superior discriminatory ability (AUC 0.682; 95% CI 0.618–0.751) compared with HALP (AUC 0.619; 95% CI 0.551–0.680). In multivariable analysis, FAR remained a strong independent predictor of preeclampsia (adjusted OR 1.263; 95% CI 1.167–1.368), whereas HALP showed a weaker association. Among combined models, FAR plus platelet distribution width (PDW) provided the highest discrimination (AUC 0.820), significantly outperforming FAR alone (DeLong p = 0.030). Conclusion: While the FAR + PDW model demonstrated improved discriminatory performance, these findings should be interpreted as preliminary. Prospective multicenter studies and external validation are necessary before such biomarkers can be considered for routine clinical use.