Increased risk of deep vein thrombosis and pulmonary thromboembolism in patients with spinal cord injury: a nationwide cohort prospective study.

BACKGROUND: We investigated the effect of spinal cord injury (SCI) on the development of deep vein thrombosis (DVT) and pulmonary thromboembolism (PE) by conducting a nationwide longitudinal cohort study.

METHODS: We studied the entire hospitalized population in Taiwan for the 1998-2008 period, with a follow-up period extending to the end of 2010. We identified SCI patients using the Taiwan National Health Insurance Research Database (NHIRD), and selected a cohort that was 1:4 frequency-matched by age (5-y span), sex, and index year from the general population. We analyzed the risks of DVT and PE using Cox proportional-hazards regression models, which included the demographic variables of sex, age, and comorbidities.

RESULTS: A total of 47,916 SCI patients (62.7% men, mean age of 50.0 y) and 191,664 controls were followed for 308,266 and 1,341,169 person-years, respectively. The adjusted hazard ratio (HR) of DVT and PE development was 2.46-fold and 1.57-fold among the SCI patients, respectively. The highest risk of DVT and PE developed within 3months after an SCI occurred (HR: 16.9 and 3.64, respectively). The adjusted HR of DVT and PE rose markedly with increasing age. The adjusted HR of DVT was highest among C-spine SCI patients, and the adjusted HR of PE was highest among T-spine SCI patients.

CONCLUSION: This nationwide prospective cohort study demonstrated that the risk of DVT and PE increased significantly in SCI patients compared with that of the general population. The highest risk of DVT and PE developed within 3months after an SCI occurred.