The Role of D-Dimer as a Diagnostic Biomarker of Thrombotic Events in Libyan Patients at EL-Beyda City

Stroke and thromboembolic events represent a global health issue of long-term disability and mortality. While neuroimaging is foundational for initial diagnosis, it has limitations in detecting subtle microvascular changes, making the integration of quantifiable blood-based biomarkers, such as D-dimer, critical for early diagnosis and prognostic evaluation. This study aims to evaluate the diagnostic utility of plasma D-dimer levels in patients with thrombosis by assessing its effectiveness as a clinical biomarker compared to healthy controls. This case-control study evaluated 120 participants aged ≥40 years, divided equally into 60 newly diagnosed thrombosis patients and 60 healthy controls at Al-Tarahum and Al-Thiqah Laboratories. Patients with chronic kidney disease, active malignancy, inflammatory disorders, or those on long-term anticoagulant therapy were excluded. Venous blood samples were collected in 3.2% sodium citrate, centrifuged, and stored at -80°C. Quantitative measurements of D-dimer were performed using the Fluorescence Immunoassay (FIA) technique via the ichroma™ system with a diagnostic cut-off value of 0.5µg/mL. Statistical analysis was conducted using SPSS version 26.0, applying independent-samples t-tests and Pearson correlation analysis. The cohort was well-balanced, consisting of 52.5% females and 47.5% males, with the majority of participants (63.3%) falling within the 40 to 60 years age group. A statistically significant positive correlation was identified between age and plasma D-dimer levels (r = 0.567, p = 0.001). Furthermore, thrombosis patients demonstrated a substantial and clinically significant elevation in mean D-dimer concentrations (1.500 ±0.32µg/mL) compared to the healthy control group (0.350 ± 0.12µg/mL, p < 0.001). Plasma D-dimer levels serve as a vital biomarker with high diagnostic and predictive value in thrombotic conditions, exhibiting a strong, statistically significant elevation in patients and a positive correlation with advancing age.