Short- and long-term mortality after pulmonary embolism in patients with and without cancer

Pulmonary embolism (PE) is a major cause of mortality and morbidity. It is known that the risk of death varies by provoking factors; however, it is unknown if the risk of death persists beyond the initial diagnosis among patients with cancer-associated and non-cancer provoked patients. In this study, we aimed to investigate the effect of cancer on overall, short- and long-term mortality in a cohort of consecutive incident PE patients. Using administrative databases, we identified all incident cases of PE between 2004 and 2012 in Alberta, Canada. Cases were stratified by provoking factors (i.e. unprovoked, provoked, and cancer-associated). A multivariate Cox survival model was used to estimate the hazard ratios of short- and long-term death. We identified 8641 patients with PE, among which 42.2% were unprovoked, 37.9% were provoked and 19.9% were cancer-associated. The 1-year and 5-year survival probabilities were 60% (95% CI: 57-64%) and 39% (95% CI: 36-43%) in patients with cancer-associated PE, 93% (95% CI: 92-94%) and 80% (95% CI: 78-81%) in provoked PE, and 94% (95% CI: 93-95%) and 85% (95% CI: 83-87%) in unprovoked PE, respectively. Compared to patients with unprovoked events, both short-term and long-term survival in patients with cancer-associated PE have a higher observed risk of all-cause mortality in all age groups ( p<0.001). In contrast, patients with provoked events had a similar short- and long-term all-cause mortality. While PE has a significant mortality in all risk groups, patients with cancer have a higher risk of short-term mortality compared to patients with unprovoked PE.