Correlation between D-dimer and postoperative outcomes in patients with aneurysmal subarachnoid hemorrhage

Abstract

OBJECTIVE: Elevated D-dimer levels indicate hypercoagulation and thromboembolic events. We investigated whether D-dimer data collected from patients with aneurysmal subarachnoid hemorrhage (aSAH) following intracranial aneurysm rupture could be statistically analyzed to determine a potential correlation between D-dimer levels and poor prognosis. METHODS: This retrospective study enrolled patients with aSAH admitted to the Second Hospital of South China University between January 2017 and April 2021. D-dimer levels were measured within 24 hours of admission, continuously monitored until discharge, and categorized into quartiles (group 1: < 0.6; group 2: 0.6 ≤ D-dimer < 1.2; group 3: 1.2 ≤ D-dimer < 2.0; group 4: ≥ 2.0). We measured D-dimer levels upon admission (before surgery), post-operative mean, mean levels during hospitalization, and peak levels during hospitalization. Data were analyzed to determine the correlation between D-dimer levels and post-discharge prognosis. The primary outcome measure was prognosis after discharge. Patient prognosis was assessed using the modified Rankin Scale (mRS), and post-discharge prognosis was confirmed by consulting the patient's family. RESULTS: A total of 355 patients participated in this study. After stratifying the D-dimer data, we performed chi-square and one-way/multi-way logistic analyses. D-dimer levels at admission, mean D-dimer levels, and the highest D-dimer levels were associated with post-discharge outcomes, even after accounting for inflammatory indicators and anticoagulant drug usage (P<0.01). D-dimer was associated with unfavorable outcomes and complications arising from the primary disease, such as lower extremity venous thrombosis and delayed cerebral ischemia (both P<0.05). Kaplan-Meier analysis of data from the four D-dimer groups revealed that patients with high D-dimer levels (≥2.0 mmol/L) had significantly higher long-term mortality rates compared to those with low D-dimer levels (<2.0 mmol/L). This suggests the significant association between D-dimer levels and the prognosis of patients with aSAH following surgery. CONCLUSIONS: Our findings suggest an association between elevated D-dimer levels following aSAH onset and the prognosis, which persists even after accounting for anticoagulant use, different surgical procedures, severity at admission, complications, and other potential confounding factors Quantifying D-dimer is an efficient approach that can be implemented during patient admission to assess long-term outcome risk and guide future postoperative treatment strategies.