Prognostic value of blood biomarkers in patients with unprovoked acute pulmonary embolism

BACKGROUND: Better outcomes have been observed in patients with acute unprovoked than provoked pulmonary embolism (PE). Prognostic biomarkers were studied in heterogeneous patient population and were not verified in patients with unprovoked PE. METHODS: Patients diagnosed with unprovoked acute PE from 2010 to 2017 at Asan Medical Center, South Korea, were analyzed retrospectively. Adverse composite outcomes were defined as thrombolysis, thrombectomy, extracorporeal membrane oxygenation, or death. Venous blood samples were collected at the first visit before anticoagulant treatment. Biomarkers associated with composite outcomes were analyzed and compared with preexisting risk models. RESULTS: This study included 265 patients (48.7% male) with a median age of 66.0 (interquartile range 52.0, 75.0) years. Composite outcomes occurred in 20 (7.5%) patients. Hemoglobin, uric acid, and glucose were significantly and independently associated with adverse composite outcomes. This biomarker model showed the highest prognostic accuracy for adverse composite outcomes, with an area under the curve of 0.806 (95% confidence interval: 0.702–0.911, P < 0.001), which was significantly better than that of PE severity index (PESI) or simplified PESI, and comparable to that of the European Society of Cardiology (ESC) risk classification. CONCLUSIONS: The biomarker model including hemoglobin, uric acid, and glucose has good prognostic performance comparable to the ESC risk classification while PESI or simplified PESI score was not useful in unprovoked PE.