Risk factors associated with provoked pulmonary embolism

This study aimed to investigate the risk factors associated with provoked pulmonary embolism (PE).

This retrospective cohort study included 237 patients with PE. Patients that had transient risk factors at diagnosis were classified as having provoked PE, with the remaining patients being classified as having unprovoked PE. The baseline clinical characteristics and factors associated with coagulation were compared. We evaluated the risk factors associated with provoked PE.

Of the 237 PE patients, 73 (30.8%) had provoked PE. The rate of respiratory failure and infection, as well as the disseminated intravascular coagulation score and ratio of right ventricular diameter to left ventricular diameter were significantly higher in patients with provoked PE than in those with unprovoked PE. The protein and activity levels associated with coagulation, including protein C antigen, protein S antigen, protein S activity, anti-thrombin III antigen, and factor VIII, were significantly lower in patients with provoked PE than in those with unprovoked PE. Multivariate analysis showed that infection (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.4 to 7.4) and protein S activity (OR, 0.97; 95% CI, 0.95 to 0.99) were significantly associated with provoked PE.

Protein S activity and presence of infection were important factors associated with provoked PE. We should pay attention to the presence of infection in patients with provoked PE.