Long-term outcomes in patients with acute pulmonary embolism after in-hospital treatment: study protocol of the prospective Lungenembolie Augsburg Studie (LEA study).

Introduction: Acute pulmonary embolism (PE) is a frequent life-threatening event and an important cause of hospitalisation, morbidity and mortality worldwide. Limited information on the long-term course of PE patients is available so far. The Lungenembolie Augsburg study will provide a view on the predisposing and PE-provoking factors, diagnostic procedures and short as well as long-term treatment options. Especially, the data on the long-term course of the disease-in combination with omics data obtained in biospecimens-will generate new knowledge regarding triggers, disease progression, treatment, long-term sequelae, prognosis and prevention of disease recurrence.

Methods And Analysis: In this prospective study, we will include about 1000 patients admitted to the university hospital of Augsburg, aged 18 years and older with a confirmed diagnosis of acute PE. At baseline, demographic information, symptoms on presentation, delay in diagnosis, predisposing and PE-provoking factors, comorbidity, quality of life, symptoms of anxiety and depression, information on invasive and non-invasive treatment procedures, complications and laboratory parameters will be collected. During the hospital stay, 30 mL blood will be collected from the patients, processed, aliquoted and frozen at -80°C. In a subgroup of patients, an eight-channel polygraphy will be carried out to assess sleep-disordered breathing. All study participants will be followed up for 60 months via postal questionnaires or telephone interviews after hospital discharge. Long-term survival, bleeding complications and PE recurrence during the follow-up are the primary study outcomes. To identify risk factors and determinants associated with these outcomes, confounder-adjusted Cox-regressions will be used for modelling and to estimate relative risks. Effect modification by age and sex will be examined.

Ethics And Dissemination: The study protocol was approved by the Ethics Committee of the Ludwig-Maximilians-Universität München (Date of approval: 1 August 2017, Reference number: 17-378). Study results will be presented at national and international conferences and published in peer-reviewed scientific journals.