Objective:

To evaluate whether the fibrinogen−to−albumin ratio (FAR) provides incremental prognostic value for identifying preeclamptic patients at high risk of adverse peripartum events, defined as a composite adverse perinatal outcome (CAPO) that serves as a surrogate for severe disease burden, and to explore its potential utility in guiding anesthesia−relevant decisions.

Key Findings:

• Model A achieved an AUC of 0.852 (95% CI 0.818–0.887), while Model B improved to 0.888 (95% CI 0.859–0.917; P < 0.001).
• Model B showed favorable calibration (Hosmer–Lemeshow, P = 0.594) and a lower Brier score (0.134 vs. 0.153).
• At an optimal FAR cutoff of 0.135, Model B had a sensitivity of 0.864 and specificity of 0.740 for predicting CAPO.
• In the external validation cohort, Model B maintained robust discrimination (AUC 0.856, 95% CI 0.808–0.904) and outperformed Model A (AUC 0.798, 95% CI 0.740–0.857; P = 0.003).
• The addition of FAR resulted in a ΔAUC of 0.010 (95% CI 0.002–0.019; P = 0.013), continuous NRI of 0.397 (95% CI 0.268–0.526; P < 0.001), and IDI of 0.022 (95% CI 0.012–0.032; P = 0.004).

Interpretation:

FAR provides statistically significant incremental prognostic value for predicting CAPO, indicating its potential utility in clinical decision-making, particularly in assessing coagulopathy and systemic inflammation.

Limitations:

Conclusion:

FAR ≥0.135 alerts to coagulopathy and systemic inflammation, supporting cautious neuraxial anesthesia, early invasive monitoring, and escalated perioperative care, while also suggesting broader implications for managing preeclamptic patients.