HERDOO2 may guide duration of treatment for unprovoked VTE
Clinical Question: Can HERDOO2 guide anticoagulation cessation in women with unprovoked venous thromboembolism (VTE)?
Background: Patients with unprovoked VTE have increased recurrence rates after stopping anticoagulation, but no tools have been validated to identify low risk patients.
Study Design: A prospective cohort study.
Setting: Forty-four referral centers in seven countries.
Synopsis: Of patients with unprovoked, symptomatic VTE, 2,747 were evaluated after receiving anticoagulation for 5-12 months. HERDOO2 was used to classify women as low (0-1 points) or high (equal to or greater than 2 points) risk categories. Men were considered high risk. Anticoagulation was stopped for low risk patients. Treatment of high risk patients was left to physician choice.
Overall, high risk patients who continued anticoagulation had a 1.6% recurrence rate. Low risk women who stopped anticoagulation had a 3% recurrence rate per patient year, but postmenopausal women aged 50 years or older had a rate of 5.7%. High risk patients who stopped anticoagulation had a 7.4% recurrence rate. This study included multiple sites, but only 44% of participants were women. HERDOO2 should be used cautiously in postmenopausal women aged 50 years or older and in nonwhite women.
Bottom Line: HERDOO2 may help guide the decision to stop anticoagulation in select low-risk women with unprovoked VTE.
Citation: Rodger MA, Gregoire LG, Anderson DR, et al. Validating the HERDOO2 rule to guide treatment duration for women with unprovoked venous thrombosis: Multinational prospective cohort management study. BMJ. 2017 March;356:j1065.
Dr. Helfrich is an assistant professor in the University of Kentucky division of hospital medicine.
