Optimal length of oral anticoagulant treatment for maximum benefit within 5 years after discontinuation of oral anticoagulants in patients with acute pulmonary embolism who require secondary thromboprophylaxis.

For a total of 385 patients in group 1 (n=220), group 2 (n=110) and group 3 (n=55), the PE-related mortality in group 1 was higher than that in group 2 (p=0.034) and 3 (p=0.040), respectively, whereas were similar between groups 2 and 3 (p=1.000). The net clinical benefit in group 1 was less than that in group 2 (p=0.024), whereas similar with that in group 3 (p=0.526). The net clinical benefit was comparable between groups 2 and 3 (p=0.716). The length of OA use was positively associated with major bleeding (HR, 2.510 (0.293 to 3.485), p=0.001), whereas negatively associated with PE-related mortality (HR, 0.668 (0.196 to 2.832), p=0.025) and VTE recurrence (HR, 0.694 (0.174 to 2.300), p=0.036), respectively. The sensitivity and specificity of the length of OA use for the tendency of PE-related mortality was 70.2% and 46.2%, respectively. The area under the curve (AUC) was 0.654 (0.514 to 0.793) (p=0.029). The sensitivity and specificity of the length of OA use for the tendency of net clinical benefit was 86.8% and 64.3%, respectively. The AUC was 0.628 (0.565 to 0.690) (p<0.001) CONCLUSIONS: For patients with acute PE who require secondary thromboprophylaxis, 2 to 3 years (30 months preferred) of overall OA use after a diagnosis of acute PE could be an optimal length to achieve maximum benefit within 5 years after OA discontinuation.