A prospective cohort study has estimated the annual risk for fatal PE and disease recurrence in patients who have discontinued anticoagulant therapy.
The study involved 2052 patients with a first episode of symptomatic venous thromboembolism (VTE: 1450 DVT, 310 PE, and 292 DVT and PE) who discontinued anticoagulant therapy. The mean duration of previous anticoagulant therapy was six months and the mean duration of follow-up after discontinuation of treatment was 54 months.
The following data was reported:
* The annual risk for any fatal PE after discontinuation of anticoagulation was 0.49 events (95% CI, 0.36 to 0.64 events) per 100 person-years;
* The annual risk for definite or probable fatal PE after discontinuation of anticoagulation was 0.19 events (0.12 to 0.30 events) per 100 person-years;
*The case-fatality rate of recurrent disease was 9.0% (6.8% to 11.8%) for any fatal PE and 3.8% (2.4% to 5.9%) for definite or probable fatal PE.
The researchers concluded that the risk for fatal PE was 0.19 to 0.49 events per 100 person-years for patients who finished a course of anticoagulant therapy for a first episode of symptomatic VTE, while the case-fatality rate for death from recurrent PE was 4% to 9%.
They acknowledged that their findings were less pertinent to patients with active cancer, permanent immobility, or high-risk thrombophilia. In addition, decision makers should also take into account the rates of fatal PE recurrence and fatal haemorrhage if anticoagulant therapy was continued.