Incidence of Thromboembolism After Stopping Anticoagulant Therapy

Abstract

Anticoagulant therapy was discontinued because of hemorrhage on 74 occasions and stopped electively on 166 others, and the incidence of subsequent thromboembolism in these two populations compared. Patients were placed in low-, intermediate-, or high-risk categories, depending on the presence or absence of factors previously shown to be associated with significant differences in the incidence. The proportion of patients in the "hemorrhage" and "elective" populations who fell into each category was similar and the two populations were comparable in other relevant respects. Comparison by means of a chi-square contingency analysis failed to show any significant differences in the relapse rates during any part of the 16-week follow-up period. Stopping anticoaguant therapy because of hemorrhage is not therefore associated with a risk of thromboembolism which is demonstrably greater than that observed after discontinuing treatment electively.