Person: Singer, Daniel
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Publication Prediction Score for Anticoagulation Control Quality Among Older Adults
(John Wiley and Sons Inc., 2017) Lin, Kueiyu Joshua; Singer, Daniel; Glynn, Robert; Blackley, Suzanne; Zhou, Li; Liu, Jun; Dube, Gina; Oertel, Lynn B.; Schneeweiss, SebastianBackground: Time in the therapeutic range (TTR) is associated with the effectiveness and safety of vitamin K antagonist (VKA) therapy. To optimize prescribing of VKA, we aimed to develop and validate a prediction model for TTR in older adults taking VKA for nonvalvular atrial fibrillation and venous thromboembolism. Methods and Results: The study cohort comprised patients aged ≥65 years who were taking VKA for atrial fibrillation or venous thromboembolism and who were identified in the 2 US electronic health record databases linked with Medicare claims data from 2007 through 2014. With the predictors identified from a systematic review and clinical knowledge, we built a prediction model for TTR, using one electronic health record system as the training set and the other as the validation set. We compared the performance of the new models to that of a published prediction score for TTR, SAMe‐TT 2R2. Based on 1663 patients in the training set and 1181 in the validation set, our optimized score included 42 variables and the simplified model included 7 variables, abbreviated as PROSPER (Pneumonia, Renal dysfunction, Oozing blood [prior bleeding], Staying in hospital ≥7 days, Pain medication use, no Enhanced [structured] anticoagulation services, Rx for antibiotics). The PROSPER score outperformed SAMe‐TT 2R2 when predicting both TTR ≥70% (area under the receiver operating characteristic curve 0.67 versus 0.55) and the thromboembolic and bleeding outcomes (area under the receiver operating characteristic curve 0.62 versus 0.52). Conclusions: Our geriatric TTR score can be used as a clinical decision aid to select appropriate candidates to receive VKA therapy and as a research tool to address confounding and treatment effect heterogeneity by anticoagulation quality.
Publication Prevalence, Characteristics, and Outcomes of Valvular Heart Disease in Patients With Atrial Fibrillation: Insights From the ORBIT‐AF (Outcomes Registry for Better Informed Treatment for Atrial Fibrillation)
(John Wiley and Sons Inc., 2017) Thomas, Kevin L.; Jackson, Larry R.; Shrader, Peter; Ansell, Jack; Fonarow, Gregg C.; Gersh, Bernard; Kowey, Peter R.; Mahaffey, Kenneth W.; Singer, Daniel; Thomas, Laine; Piccini, Jonathan P.; Peterson, Eric D.Background: The presence of valvular heart disease (VHD) may affect the risk of stroke and mortality in patients with atrial fibrillation (AF). Community‐based estimates of prevalence and outcomes of specific forms of VHD in patients with AF are lacking. Methods and Results: We examined the prevalence of VHD, anticoagulation use, mortality, stroke/transient ischemic attack, and bleeding among a community cohort of patients with AF. Significant VHD was defined as follows: (1) moderate/severe mitral stenosis or mechanical valve; (2) bioprosthetic valve, surgical repair, or balloon valvuloplasty; and (3) moderate/severe aortic regurgitation or stenosis, mitral regurgitation, or tricuspid regurgitation. Proportional hazards models were performed to test the association between VHD groups and outcomes. Among 9748 patients with AF, 2705 (27.7%) had significant VHD. Anticoagulation use was highest among patients with mitral stenosis/mechanical valve (91.8%). Compared with individuals with no significant VHD, individuals with aortic regurgitation/aortic stenosis, mitral regurgitation, or tricuspid regurgitation (hazard ratio, 1.23; 95% confidence interval, 1.07–1.42) had the highest risk of death. There were no differences in stroke or transient ischemic attack and major bleeding among individuals with and without significant VHD. Patients with AF and aortic stenosis had the highest risk of death (hazard ratio, 1.32; 95% confidence interval, 1.08–1.62). Conclusions: Significant VHD is common among patients with AF in community practice. In a community cohort of patients with AF and CHA 2 DS 2‐VASc score ≥2, most were anticoagulated. Individuals with AF and moderate‐to‐severe biological VHD have more comorbidities and a higher mortality risk; however, stroke and major bleeding are similar among those with and without significant VHD.
Publication Effects of Non–Vitamin K Antagonist Oral Anticoagulants Versus Warfarin in Patients With Atrial Fibrillation and Valvular Heart Disease: A Systematic Review and Meta‐Analysis
(John Wiley and Sons Inc., 2017) Pan, Kuo‐Li; Singer, Daniel; Ovbiagele, Bruce; Wu, Yi‐Ling; Ahmed, Mohamed A.; Lee, MengBackground: The original non–vitamin K antagonist oral anticoagulant (NOAC) trials in nonvalvular atrial fibrillation (AF) enrolled patients with native valve pathologies. The object of this study was to quantify the benefit–risk profiles of NOACs versus warfarin in AF patients with native valvular heart disease (VHD). Methods and Results: Trials were identified by exhaustive literature search. Trial data were combined using inverse variance weighting to produce a meta‐analytic summary hazard ratio (HR) and 95% confidence interval (CI) of efficacy and safety of NOACs versus warfarin. Our final analysis included 4 randomized controlled trials that enrolled 71 526 participants, including 13 574 with VHD. Pooling results from included trials showed that NOACs versus warfarin reduced stroke or systemic embolism (HR: 0.70; 95% CI, 0.60–0.82) and intracranial hemorrhage (HR: 0.47; 95% CI, 0.24–0.92) in AF patients with VHD. However, risk reduction of major bleeding and intracranial hemorrhage was driven by apixaban, edoxaban, and dabigatran (HR for major bleeding: 0.79 [95% CI, 0.69–0.91]; HR for intracranial hemorrhage: 0.33 [95% CI, 0.25–0.45]) but not rivaroxaban (HR for major bleeding: 1.56 [95% CI, 1.20–2.04]; HR for intracranial hemorrhage: 1.27 [95% CI, 0.77–2.10]). Conclusions: Among patients with AF and native VHD, NOACs reduce stroke and systemic embolism compared with warfarin. Evidence shows that apixaban, dabigatran, and edoxaban also reduce bleeding in this patient subgroup, whereas major bleeding (but not intracranial hemorrhage or mortality rate) is significantly increased in VHD patients treated with rivaroxaban. NOACs are a reasonable alternative to warfarin in AF patients with VHD.