Predicting adverse outcome in outpatients with acute deep vein thrombosis. findings from the RIETE Registry.

BACKGROUND: Home treatment of patients with acute deep vein thrombosis (DVT) leads to cost savings and improved quality of life. However, little information is known about what influences the clinical outcome in these patients.

METHODS: The Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) is an ongoing registry of consecutive patients with symptomatic, objectively confirmed, acute DVT or pulmonary embolism (PE). In this analysis evaluated the clinical outcome <or=15 days of the start of therapy of all enrolled outpatients with acute DVT in the lower limbs.

RESULTS: During the study period, 124 (2.8%) of 4405 DVT patients had at least one adverse event (symptomatic PE, 15; recurrent DVT, 18; major bleeding, 37; death, 68). On multivariate analysis, bilateral DVT, renal insufficiency, body weight <70 kg, recent immobility, chronic heart failure, and cancer were associated with an increased risk for adverse events. When these variables were added into the derivation sample, the area under receiver operator characteristic (ROC) curve was 0.81 (95% confidence interval [CI], 0.76 to 0.86). Patients with a risk score of <or=2 had a 1.2% incidence of adverse events (23 in 1935 patients) compared with the 6.8% incidence in high-risk patients. In the validation sample, the area under ROC curve was 0.79 (95% CI, 0.70 to 0.88). Low-risk patients had a 1.0% incidence of adverse events, and those at high-risk had a 4.7% incidence.

CONCLUSION: A simple risk score based on easily available variables can identify DVT outpatients at low risk for an adverse outcome. This information may help clinicians to decide which DVT patients may be eligible for ambulatory treatment.