Lower red blood cell count is a risk factor for higher D-dimer level in patients with spinal cord injury: A five year retrospective cross-sectional study

This study aims to elucidate the relationship between red blood cell (RBC) count and D-dimer levels in patients with spinal cord injury, with the goal of identifying potential therapeutic targets for minimizing D-dimer levels. An observational, retrospective, cross-sectional, single center study. Individuals with SCI (576 cases) admitted to a rehabilitation medicine department. After exclusions, we divided the participants (n = 308) into two groups based on their D-dimer levels: Group 1 (≤0.5 mg/L, n = 64) and Group 2 (>0.5 mg/L, n = 244). Key variables such as deep vein thrombosis (DVT), anticoagulant therapy, pulmonary infection, injury characteristics, and hematological parameters were analyzed for their association with RBC counts and D-dimer levels. DVT and anticoagulant therapy emerged as significant covariates. A comprehensive analysis identified a negative linear correlation between RBC counts and D-dimer levels, markedly more pronounced in Group 2. For every 1.00 × 1012/L increase in RBC, D-dimer levels decreased by 1.93 mg/L in Group 2, compared to a 0.02 mg/L decrease in Group 1. Higher RBC counts might be associated with lower D-dimer levels in patients with SCI, especially in those with higher initial D-dimer levels. This association highlights a potential therapeutic focus on managing RBC counts to decrease D-dimer level, which may mitigate the risk of DVT formation in patients with SCI.