Overview of meta-analyses of NOACs versus warfarin in patients with atrial fibrillation




Poster session 2


Monday 24 October 2016 - 15:30 to 16:00


All authors in correct order:

Origasa H1
1 University of Toyama School of Medicine, Japan
Presenting author and contact person

Presenting author:

Hideki Origasa

Contact person:

Abstract text
Background: New oral anticoagulants (NOACs) have been launched as an alternative to warfarin. Since there is big interest in the clinical usefulness of NOACs versus warfarin, numerous network meta-analyses have been published.

Objectives: To overview the meta-analysis publications and explore the varying elements in their conclusions.

Methods: We searched MEDLINE for meta-analyses comparing NOACs with warfarin. Of 49 identified citations, only nine were irrelevant. So our sample consisted of 40 meta-analysis articles. Study characteristics such as nationality, journal, number of included studies and number of participants in meta-analysis, comparison arms and conclusions were collected from the abstract of each publication.

Results: The meta-analyses were published from December 2010 onwards. Fifteen (38%) of the 40 meta-analyses came from the USA, followed by Italy (n = 5, 13%), UK, Germany, France, Canada (n = 3, 8% each). Six articles (15%) came from the American Journal of Cardiology, followed by the International Journal of Cardiology (5 articles, 13%) and PLOS One (3 articles, 8%). Most meta-analyses included fewer than 10 studies (n = 25, 63%), and 58% had more than 10,000 participants. Most (n = 21, 53%) compared any NOAC with warfarin, although 18 studies (45%) compared a single NOAC with warfarin, with 13 of them comparing dabigatran with warfarin. There were 18 meta-analyses favoring NOACs, 11 showed a similar result, and six showed worsening with NOACs. In half of these trials the worsening with NOACs was related to myocardial infarction. A proportion showed the proportion of outcomes favoring NOACs was gradually increasing (37% for 2013 or earlier, 45% in 2014, and 56% in 2015).

Conclusions: Forty meta-analyses comparing NOACs with warfarin have been published since 2010. Some journals published multiple articles, despite a similar objective.