Incidence and Prevention of Postoperative Venous Thromboembolism: Are They Meaningful Quality Indicators in Japanese Health Care Settings?

Venous thromboembolism (VTE) epidemiology varies widely across surgical procedures. At present, there are few epidemiologic reports regarding VTE in Japan. Japanese VTE prophylaxis guidelines recommend a risk-based approach based on previous epidemiologic statistics. VTE includes deep vein thrombosis (DVT) and pulmonary embolism (PE). PE prevention is the main goal, although the relation between PE and DVT is still controversial. We collected administrative data for 1,016,496 surgical patients from 260 hospitals. We analyzed DVT and PE incidence and selected two subgroups for further analysis: gastroenterologic surgery and specific orthopedic surgery (high-frequency group). Overall DVT incidence was 1947 (0.19%); and the PE incidence was 538 (0.05%). DVT case fatality rate was 3.44% (67/1947); that for PE was 22.86% (123/538). Both overall and subgroup incidences were comparable to those in previous reports. Subgroup analyses in the high-frequency group did not show a relation between DVT and PE. VTE prophylaxis did not show a relation between DVT and PE despite 99% adherence. Our results are consistent with established data regarding DVT and PE incidence. Administrative data available in Japan provides a powerful epidemiologic tool to characterize rare diseases such as DVT and PE. DVT is not a suitable quality indicator in Japan. However, PE is too rare to be considered a rate-based outcome indicator, and VTE prophylaxis is too widely applied to be used as a process indicator. VTE measurement is not a useful quality indicator in Japan to compare hospitals but provides a longitudinal self-survey.