Trends of Hospital-Acquired Lower Extremity Deep Venous Thrombosis in an Academic Medical Center in China from 2007 to 2021

Background: This study aimed to evaluate the demographic characteristics and changing trends in the incidence of hospital-acquired lower extremity deep venous thrombosis (HALEDVT) in Chinese inpatients over the course of 15 years. Methods: We performed a retrospective analysis of the HA-LEDVT events in a medical center between January 1, 2007, and December 31, 2021. Results: A total of 846,347 eligible patients were analyzed. The overall incidence of HA-LEDVT was 2.53 per 1,000 admissions. The incidence was 0.22 and 4.20 per 1,000 admissions in 2007 and 2017, respectively (P < 0.01). Medical patients had a higher incidence of HA-LEDVT than surgical patients (3.19 vs. 2.14 per 1,000 admissions; P < 0.01). The incidence of HA-LEDVT increased from 0.28 to 11.90 per 1,000 admissions for those aged 17-29 years and 8089 years, respectively (P < 0.01). The increase in HA-LEDVT incidence mainly occurred in patients aged >= 60 years. The median length of stay of HA-LEDVT patients was longer than that of other eligible patients (17 vs. 7 days; P < 0.01). Most of the HA-LEDVT events (77.8%) were diagnosed between hospital day 3 and 15, and the time from admission to HA-LEDVT diagnosis decreased by year. The rate of vascular surgery consultation for diagnosed or suspected HALEDVT and HA-LEDVT-related discharge instructions both decreased by half gradually over the 15 years of this study. Isolated distal deep vein thrombosis (DVT) accounted for 83.3% of all HA-LEDVT events, and the proportion increased significantly from 62.5% in 2007 to 88.7% in 2021 (P < 0.01). Conclusion: The incidence of HA-LEDVT has been high in the Chinese population. More highquality prospective studies are needed to guide prevention of HA-LEDVTs.