Research Trends in Anticoagulation Therapy over the Last 25 Years

A large volume of literature has become available to practitioners prescribing anticoagulants. The aim of this study was to analyze the bibliometric characteristics of the top 100 most cited articles related to anticoagulation over the past 25 years, with special consideration to impact of direct or "nonvitamin K antagonist" oral anticoagulants (NOACs) compared with vitamin K antagonists. A bibliometric analysis of the 100 most cited journal articles related to anticoagulants published between 1994 and 2019 was performed in April 2019. The top 100 articles by citation count were analyzed to extract bibliometric data related to journal title, impact factor, year of publication, place of publication, anticoagulant studied, indication for anticoagulation, study design, and conflicts of interest. The median (interquartile range) number of citations per article was 806 (621-1,085). The anticoagulant most frequently researched was warfarin (37%). NOAC publications (21%) grew at a relative rate of 3.4 times faster compared with all publications. The indication most commonly researched was venous thromboembolism (26%). Eighty articles constituted level I or II evidence, with randomized controlled trials the most common type of study (74). A financial conflict of interest was declared in 87% of articles with private, for-profit organizations the most common source of funding (26%). In summary, top research related to anticoagulation is highly impactful but may be at risk of sponsorship bias. High-level evidence for NOACs continues to expand across a range of indications with citation metrics likely to soon approach or surpass that of older drugs.