Venous thromboembolism and amyotrophic lateral sclerosis: the Venous Thrombo-Embolism and Sclerosis Lateral Amyotrophic study

Background: Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease. Given the inflammatory nature of ALS and the high number of ALS-related clinical circumstances (eg, prolonged immobilization and infections), patients with ALS may have a high risk of venous thromboembolism (VTE). Objectives: To determine the annual incidence rate of VTE and the predictors of VTE in patients with ALS. Methods: We analyzed a prospective cohort of patients with ALS diagnosed between 2009 and 2019 followed in the Brest University Hospital ALS Centre. Results: Among 227 patients with ALS, VTE occurred in 19 patients during a median follow-up period of 717 days (IQR, 488-1308), yielding an annual incidence rate of 2.93% (95% CI, 1.88%-4.53%). Predictors for VTE were a family history of VTE (hazard ratio [HR], 15.24; 95% CI, 1.72-134.84; P = .01), the presence of noninvasive ventilation at ALS diagnosis (HR, 6.98; 95% CI, 1.09-44.59; P = .04) and a short time (ie, <213 days) between first symptoms and ALS diagnosis (HR, 5.48; 95% CI, 1.57-19.11; P = .01). Recurrent VTE occurred within 3 months after stopping anticoagulation in 5 patients (26.3%). Conclusion: The annual incidence of VTE in patients with ALS is high. Predictive factors of VTE were a VTE history, noninvasive ventilation, and a short time between first symptoms of ALS and ALS diagnosis.