Definitions, adjudication, and reporting of pulmonary embolism-related death in clinical studies: a systematic review.

Kraaijpoel, Noémie; Tritschler, Tobias; Guillo, Enora; Girard, Philippe; Le Gal, Grégoire

BACKGROUND Pulmonary embolism (PE)-related death is a component of the primary outcome in many venous thromboembolism (VTE) studies. The absence of a standardized definition for PE-related death hampers study outcome evaluation and between-study comparisons. OBJECTIVES To summarize definitions for PE-related death used in recent VTE studies and to assess the PE-related death rate. PATIENTS/METHODS A systematic literature search was conducted on April 26th , 2018 from January 1st , 2014 up to the search date in MEDLINE, Embase, and CENTRAL. Cohort studies and randomized trials in which PE-related death was included in the primary outcome were eligible. Screening of titles, abstracts, and full-text articles, and data extraction were independently performed in duplicate by two authors. Study outcomes included the definition for PE-related death, VTE case-fatality rate, and death due to PE rate. Descriptive statistics were used to analyze the data. RESULTS Of the 6,807 identified citations, 83 studies were included of which 27% were randomized trials, 31% were prospective and 42% retrospective cohort studies. Thirty-five studies (42%) had a central adjudication committee. Thirty-eight (46%) reported a definition for PE-related death of which the most frequently used components were 'autopsy-confirmed PE' (50%), 'objectively confirmed PE before death' (55%), and 'unexplained death' (58%). Median VTE case-fatality rate was 1.8% (interquartile range, 0.0 to 13). CONCLUSIONS Only half of the included studies reported definitions for PE-related death, which were very heterogeneous. Case-fatality rate of VTE events varied widely across studies. Standardization of the definition and guidance on adjudication and reporting of PE-related death is needed. This article is protected by copyright. All rights reserved.