Effectiveness and Safety of Dabigatran and Warfarin in Real‐World US Patients With Non‐Valvular Atrial Fibrillation: A Retrospective Cohort Study

Abstract

BackgroundThe recent availability of dabigatran, a novel oral anticoagulant, provided a new treatment option for stroke prevention in atrial fibrillation beyond warfarin, the main therapy for years. Little is known about their real‐world comparative effectiveness and safety, even less among patient demographic and clinical subgroups.Methods and ResultsUsing a cohort of non‐valvular AF patients initiating anticoagulation from October 2010 to December 2012 drawn from a large US database of commercial and Medicare supplement claims, we applied propensity score weights to Cox proportional hazards regression to assess the comparative effectiveness and safety of dabigatran versus warfarin. Analyses were repeated among clinical and demographic subgroups using stratum‐specific propensity scores as an exploratory analysis. Of the 64 935 patients initiating anticoagulation, 32.5% used dabigatran. Compared with warfarin, dabigatran was associated with a lower risk of ischemic stroke or systemic embolism (composite adjusted Hazard Ratio [aHR], 95% CI: 0.86, 95% CI: 0.79 to 0.93), hemorrhagic stroke (aHR: 0.51, 0.40 to 0.65), and acute myocardial infarction (aHR: 0.88, 95% CI: 0.77 to 0.99), and no relation was seen between dabigatran and the composite harm outcome (aHR: 0.94, 95% CI: 0.87 to 1.01). However, dabigatran was associated with a higher risk of gastrointestinal bleeding (aHR: 1.11, 95% CI: 1.02 to 1.22). Estimates of effectiveness and safety appeared to be mostly similar across subgroups.ConclusionsDabigatran could be a safe and potentially more effective alternative to warfarin in patients with atrial fibrillation managed in routine practice settings.

Evolving Treatments for Arterial and Venous Thrombosis

“…Postmarketing data from prospective observational studies, registries, insurance claim databases, and pharmacovigilance networks suggest that the effectiveness and safety of the DOACs in practice are consistent with the findings of the clinical trials (Table 5). [111][112][113][114][115][116][117][118][119][120][121][122][123][124] Additional studies are ongoing, but the results observed to date have encouraged the uptake of the DOACs for the licensed indications. 125 …”

Dabigatran Versus Warfarin for Atrial Fibrillation in Real-World Clinical Practice

“…[10][11][12][13][14][15][16] One study was initially identified as a conference abstract 17 ; however, data were updated when the full article became available. 10 Another study was available only as a conference abstract.…”

Comparison of treatment effect estimates of non-vitamin K antagonist oral anticoagulants versus warfarin between observational studies using propensity score methods and randomized controlled trials

“…We screened full-length texts for 83 potentially included studies, with a Kappa statistic of 0.82 (95 % CI 0.68-0.96) between the reviewers. Fifteen studies (five RCTs [39][40][41][42][43], ten PS studies including seven full-length texts [44][45][46][47][48][49][50] and three abstracts [51][52][53]) met the inclusion criteria and were included in the final meta-analyses. The study selection process for this systematic review is shown in Fig.…”

“…Among the 10 PS studies [44][45][46][47][48][49][50][51][52][53] (Table 1), there were 494,964 patients in total included for PS analyses. Except for the two abstracts with unknown sex composition [51,53], the proportion of female sex was 46 % (n = 139,973) in the remaining eight studies.…”