Asthma and risk of pulmonary thromboembolism.

We read with interest the article by CHUNG et al. [1] about the risk of pulmonary thromboembolism in asthmatic patients. This nationwide population cohort study suggests that the risk of developing pulmonary thromboembolism significantly is increased in asthmatic patients compared to those of the general population, with a multivariable-adjusted hazard ratio of 3.24 (95% CI 1.74–6.01). The authors considered that as concentrations of thrombin were elevated in the sputum and bronchoalveolar lavage of asthmatic patients, and as local coagulation activation existed in asthma, it is possible that the results of this study may, in part, be explained through this mechanism. However, there are other plausible mechanisms that might explain the risk.