Pulmonary Thromboembolism Developed During Hospitalization: A Nationwide Retrospective Observational Study Using Claims Data

INTRODUCTION: Evidence regarding the development of pulmonary thromboembolism (PE) during hospitalization is unclear. We hypothesized that the incidence of PE could vary depending on clinical department and aimed to conduct a survey on the incidence of in-hospital PE. METHODS: We conducted a retrospective analysis using claims data of in-hospital patients in Japan. We collected background information regarding patients with and without PE occurrence during hospitalization. Further, we determined the incidence of PE and implemented prophylactic procedures in patients with and without surgery according to clinical department at admission. Finally, we examined the duration of hospital stay and in-hospital mortality rates in patients with and without PE. RESULTS: We found that 5007 (0.107%, 20.61 per 1000 person-years) patients developed PE during hospitalization and differed by clinical department at admission. Moreover, 2272 (0.095%, 19.3 per 1000 person-years) and 2735 (0.119%, 21.8 per 1000 person-years) patients with and without surgery, respectively, developed PE during hospitalization (P < 0.001). Further, 33.8% of inpatients underwent prophylactic procedures for PE; however, the implementation rate differed between patients with and without surgery (59.2% vs. 7.3%, P < 0.001). The median duration of hospital stay in patients with and without PE was 31.0 and 11.0 days, and the in-hospital mortality rates in patients with and without PE were 11.0% and 3.5%, respectively (P < 0.001). DISCUSSION: The incidence of in-hospital PE differed according to patient characteristics, clinical departments, and presence/absence of surgery. The onset of PE during hospitalization leads to prolonged hospital stay and in-hospital death. CONCLUSION: It is important to conduct a proper risk assessment on admission as well as to implement proper prophylactic procedures to prevent the development of PE during hospitalization. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40119-022-00290-6.