Abstract Body (Do not enter title and authors here): Background:
Among patients with venous thromboembolism (VTE), both major bleeding associated with anticoagulation and recurrent VTE contribute to poor prognosis and impaired quality of life. While low body weight (BW) has been identified as a bleeding risk factor, there are limited data on its impact on clinical outcomes in the era of direct oral anticoagulants (DOACs).
Purpose:
This study aimed to evaluate the association between low BW and long-term clinical outcomes in patients with VTE using a large-scale, real-world observational database.
Methods:
We used data from the COMMAND VTE Registry-2, which enrolled 5197 consecutive patients with acute symptomatic VTE at 31 centers in Japan between January 2015 and August 2020. The study population consisted of 4959 patients with available BW value, who were divided into two groups: 2897 patients with low BW (≤60 kg) and 2062 patients with non-low BW (>60 kg). The primary outcome was major bleeding; secondary outcomes included recurrent VTE and all-cause death.
Results:
The mean age of the study population was 67.7 ± 15.5 years. Compared with the non-low BW group, the low BW group had a lower mean BW (49.5 ± 7.3 kg vs. 72.2 ± 10.9 kg), was older (71.3 ± 15.0 years vs. 62.5 ± 14.8 years, P<0.001), and included a higher proportion of female patients (75% vs. 36%, P<0.001). DOACs were administered to 3940 patients (79%) as oral anticoagulation therapy. The proportion of patients receiving initial intensive treatment of DOACs was lower, whereas reduced maintenance doses of DOACs were more common in the low BW group than in the non-low BW group (30% vs. 42%, P<0.001; 52% vs. 15%, P<0.001, respectively). The cumulative 5-year incidence of major bleeding and all-cause death were significantly higher in the low BW group than in the non-low BW group (16.7% vs. 10.8%, P<0.001; 38.9% vs. 23.2%, P<0.001, respectively), even after adjusting for confounders (HR 1.43, 95%CI 1.15–1.77, P=0.001; HR 1.59, 95%CI 1.39–1.81, P<0.001, respectively). However, the cumulative 5-year incidence of recurrent VTE did not differ significantly between the two groups (9.4% vs. 9.7%, P=0.75), with no excess risk of low BW relative to non-low BW after adjusting for confounders (HR 0.98, 95%CI 0.75–1.29, P=0.90).
Conclusions:
In the DOAC era, low BW remains significantly associated with an increased risk of major bleeding and all-cause mortality among patients with VTE, whereas it was not associated with an increased risk of VTE recurrence.