Browsing by Author "Olson, DaiWai M"

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    A risk score for in-hospital death in patients admitted with ischemic or hemorrhagic stroke.
    (J Am Heart Assoc, 2013-01-28) Smith, Eric E; Shobha, Nandavar; Dai, David; Olson, DaiWai M; Reeves, Mathew J; Saver, Jeffrey L; Hernandez, Adrian F; Peterson, Eric D; Fonarow, Gregg C; Schwamm, Lee H
    BACKGROUND: We aimed to derive and validate a single risk score for predicting death from ischemic stroke (IS), intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH). METHODS AND RESULTS: Data from 333 865 stroke patients (IS, 82.4%; ICH, 11.2%; SAH, 2.6%; uncertain type, 3.8%) in the Get With The Guidelines-Stroke database were used. In-hospital mortality varied greatly according to stroke type (IS, 5.5%; ICH, 27.2%; SAH, 25.1%; unknown type, 6.0%; P<0.001). The patients were randomly divided into derivation (60%) and validation (40%) samples. Logistic regression was used to determine the independent predictors of mortality and to assign point scores for a prediction model in the overall population and in the subset with the National Institutes of Health Stroke Scale (NIHSS) recorded (37.1%). The c statistic, a measure of how well the models discriminate the risk of death, was 0.78 in the overall validation sample and 0.86 in the model including NIHSS. The model with NIHSS performed nearly as well in each stroke type as in the overall model including all types (c statistics for IS alone, 0.85; for ICH alone, 0.83; for SAH alone, 0.83; uncertain type alone, 0.86). The calibration of the model was excellent, as demonstrated by plots of observed versus predicted mortality. CONCLUSIONS: A single prediction score for all stroke types can be used to predict risk of in-hospital death following stroke admission. Incorporation of NIHSS information substantially improves this predictive accuracy.
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    Association of Preceding Antithrombotic Treatment With Acute Ischemic Stroke Severity and In-Hospital Outcomes Among Patients With Atrial Fibrillation.
    (JAMA, 2017-03) Xian, Ying; O'Brien, Emily C; Liang, Li; Xu, Haolin; Schwamm, Lee H; Fonarow, Gregg C; Bhatt, Deepak L; Smith, Eric E; Olson, DaiWai M; Maisch, Lesley; Hannah, Deidre; Lindholm, Brianna; Lytle, Barbara L; Pencina, Michael J; Hernandez, Adrian F; Peterson, Eric D
    Importance:Antithrombotic therapies are known to prevent stroke for patients with atrial fibrillation (AF) but are often underused in community practice. Objectives:To examine the prevalence of patients with acute ischemic stroke with known history of AF who were not receiving guideline-recommended antithrombotic treatment before stroke and to determine the association of preceding antithrombotic therapy with stroke severity and in-hospital outcomes. Design, Setting, and Participants:Retrospective observational study of 94 474 patients with acute ischemic stroke and known history of AF admitted from October 2012 through March 2015 to 1622 hospitals participating in the Get With the Guidelines-Stroke program. Exposures:Antithrombotic therapy before stroke. Main Outcomes and Measures:Stroke severity as measured by the National Institutes of Health Stroke Scale (NIHSS; range of 0-42, with a higher score indicating greater stroke severity and a score ≥16 indicating moderate or severe stroke), and in-hospital mortality. Results:Of 94 474 patients (mean [SD] age, 79.9 [11.0] years; 57.0% women), 7176 (7.6%) were receiving therapeutic warfarin (international normalized ratio [INR] ≥2) and 8290 (8.8%) were receiving non-vitamin K antagonist oral anticoagulants (NOACs) preceding the stroke. A total of 79 008 patients (83.6%) were not receiving therapeutic anticoagulation; 12 751 (13.5%) had subtherapeutic warfarin anticoagulation (INR <2) at the time of stroke, 37 674 (39.9%) were receiving antiplatelet therapy only, and 28 583 (30.3%) were not receiving any antithrombotic treatment. Among 91 155 high-risk patients (prestroke CHA2DS2-VASc score ≥2), 76 071 (83.5%) were not receiving therapeutic warfarin or NOACs before stroke. The unadjusted rates of moderate or severe stroke were lower among patients receiving therapeutic warfarin (15.8% [95% CI, 14.8%-16.7%]) and NOACs (17.5% [95% CI, 16.6%-18.4%]) than among those receiving no antithrombotic therapy (27.1% [95% CI, 26.6%-27.7%]), antiplatelet therapy only (24.8% [95% CI, 24.3%-25.3%]), or subtherapeutic warfarin (25.8% [95% CI, 25.0%-26.6%]); unadjusted rates of in-hospital mortality also were lower for those receiving therapeutic warfarin (6.4% [95% CI, 5.8%-7.0%]) and NOACs (6.3% [95% CI, 5.7%-6.8%]) compared with those receiving no antithrombotic therapy (9.3% [95% CI, 8.9%-9.6%]), antiplatelet therapy only (8.1% [95% CI, 7.8%-8.3%]), or subtherapeutic warfarin (8.8% [95% CI, 8.3%-9.3%]). After adjusting for potential confounders, compared with no antithrombotic treatment, preceding use of therapeutic warfarin, NOACs, or antiplatelet therapy was associated with lower odds of moderate or severe stroke (adjusted odds ratio [95% CI], 0.56 [0.51-0.60], 0.65 [0.61-0.71], and 0.88 [0.84-0.92], respectively) and in-hospital mortality (adjusted odds ratio [95% CI], 0.75 [0.67-0.85], 0.79 [0.72-0.88], and 0.83 [0.78-0.88], respectively). Conclusions and Relevance:Among patients with atrial fibrillation who had experienced an acute ischemic stroke, inadequate therapeutic anticoagulation preceding the stroke was prevalent. Therapeutic anticoagulation was associated with lower odds of moderate or severe stroke and lower odds of in-hospital mortality.
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    Clinical Effectiveness of Direct Oral Anticoagulants vs Warfarin in Older Patients With Atrial Fibrillation and Ischemic Stroke: Findings From the Patient-Centered Research Into Outcomes Stroke Patients Prefer and Effectiveness Research (PROSPER) Study.
    (JAMA neurology, 2019-07-22) Xian, Ying; Xu, Haolin; O'Brien, Emily C; Shah, Shreyansh; Thomas, Laine; Pencina, Michael J; Fonarow, Gregg C; Olson, DaiWai M; Schwamm, Lee H; Bhatt, Deepak L; Smith, Eric E; Hannah, Deidre; Maisch, Lesley; Lytle, Barbara L; Peterson, Eric D; Hernandez, Adrian F
    Importance:Current guidelines recommend direct oral anticoagulants (DOACs) over warfarin for stroke prevention in patients with atrial fibrillation (AF) who are at high risk. Despite demonstrated efficacy in clinical trials, real-world data of DOACs vs warfarin for secondary prevention in patients with ischemic stroke are largely based on administrative claims or have not focused on patient-centered outcomes. Objective:To examine the clinical effectiveness of DOACs (dabigatran, rivaroxaban, or apixaban) vs warfarin after ischemic stroke in patients with AF. Design, Setting, and Participants:This cohort study included patients who were 65 years or older, had AF, were anticoagulation naive, and were discharged from 1041 Get With The Guidelines-Stroke-associated hospitals for acute ischemic stroke between October 2011 and December 2014. Data were linked to Medicare claims for long-term outcomes (up to December 2015). Analyses were completed in July 2018. Exposures:DOACs vs warfarin prescription at discharge. Main Outcomes and Measures:The primary outcomes were home time, a patient-centered measure defined as the total number of days free from death and institutional care after discharge, and major adverse cardiovascular events. A propensity score-overlap weighting method was used to account for differences in observed characteristics between groups. Results:Of 11 662 survivors of acute ischemic stroke (median [interquartile range] age, 80 [74-86] years), 4041 (34.7%) were discharged with DOACs and 7621 with warfarin. Except for National Institutes of Health Stroke Scale scores (median [interquartile range], 4 [1-9] vs 5 [2-11]), baseline characteristics were similar between groups. Patients discharged with DOACs (vs warfarin) had more days at home (mean [SD], 287.2 [114.7] vs 263.0 [127.3] days; adjusted difference, 15.6 [99% CI, 9.0-22.1] days) during the first year postdischarge and were less likely to experience major adverse cardiovascular events (adjusted hazard ratio [aHR], 0.89 [99% CI, 0.83-0.96]). Also, in patients receiving DOACs, there were fewer deaths (aHR, 0.88 [95% CI, 0.82-0.95]; P < .001), all-cause readmissions (aHR, 0.93 [95% CI, 0.88-0.97]; P = .003), cardiovascular readmissions (aHR, 0.92 [95% CI, 0.86-0.99]; P = .02), hemorrhagic strokes (aHR, 0.69 [95% CI, 0.50-0.95]; P = .02), and hospitalizations with bleeding (aHR, 0.89 [95% CI, 0.81-0.97]; P = .009) but a higher risk of gastrointestinal bleeding (aHR, 1.14 [95% CI, 1.01-1.30]; P = .03). Conclusions and Relevance:In patients with acute ischemic stroke and AF, DOAC use at discharge was associated with better long-term outcomes relative to warfarin.
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    Development and initial testing of the stroke rapid-treatment readiness tool.
    (J Neurosci Nurs, 2014-10) Olson, DaiWai M; Cox, Margueritte; Constable, Mark; Britz, Gavin W; Lin, Cheryl B; Zimmer, Louise O; Fonarow, Gregg C; Schwamm, Lee H; Peterson, Eric D
    No instruments are currently available to help health systems identify target areas for reducing door-to-needle times for the administration of intravenous tissue plasminogen activator to eligible patients with ischemic stroke. A 67-item Likert-scale survey was administered by telephone to stroke personnel at 252 U.S. hospitals participating in the "Get With The Guidelines-Stroke" quality improvement program. Factor analysis was used to refine the instrument to a four-factor 29-item instrument that can be used by hospitals to assess their readiness to administer intravenous tissue plasminogen activator within 60 minutes of patient hospital arrival.
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    Perception Versus Actual Performance in Timely Tissue Plasminogen Activation Administration in the Management of Acute Ischemic Stroke.
    (J Am Heart Assoc, 2015-07-22) Lin, Cheryl B; Cox, Margueritte; Olson, DaiWai M; Britz, Gavin W; Constable, Mark; Fonarow, Gregg C; Schwamm, Lee; Peterson, Eric D; Shah, Bimal R
    BACKGROUND: Timely thrombolytic therapy can improve stroke outcomes. Nevertheless, the ability of US hospitals to meet guidelines for intravenous tissue plasminogen activator (tPA) remains suboptimal. What is unclear is whether hospitals accurately perceive their rate of tPA "door-to-needle" (DTN) time within 60 minutes and how DTN rates compare across different hospitals. METHODS AND RESULTS: DTN performance was defined by the percentage of treated patients who received tPA within 60 minutes of arrival. Telephone surveys were obtained from staff at 141 Get With The Guidelines hospitals, representing top, middle, and low DTN performance. Less than one-third (29.1%) of staff accurately identified their DTN performance. Among middle- and low-performing hospitals (n=92), 56 sites (60.9%) overestimated their performance; 42% of middle performers and 85% of low performers overestimated their performance. Sites that overestimated tended to have lower annual volumes of tPA administration (median 8.4 patients [25th to 75th percentile 5.9 to 11.8] versus 10.2 patients [25th to 75th percentile 8.2 to 17.3], P=0.047), smaller percentages of eligible patients receiving tPA (84.7% versus 89.8%, P=0.008), and smaller percentages of DTN ≤60 minutes among treated patients (10.6% versus 16.6%, P=0.002). CONCLUSIONS: Hospitals often overestimate their ability to deliver timely tPA to treated patients. Our findings indicate the need to routinely provide comparative provider performance rates as a key step to improving the quality of acute stroke care.
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    Real world effectiveness of warfarin among ischemic stroke patients with atrial fibrillation: observational analysis from Patient-Centered Research into Outcomes Stroke Patients Prefer and Effectiveness Research (PROSPER) study.
    (BMJ (Clinical research ed.), 2015-07-31) Xian, Ying; Wu, Jingjing; O'Brien, Emily C; Fonarow, Gregg C; Olson, DaiWai M; Schwamm, Lee H; Bhatt, Deepak L; Smith, Eric E; Suter, Robert E; Hannah, Deidre; Lindholm, Brianna; Maisch, Lesley; Greiner, Melissa A; Lytle, Barbara L; Pencina, Michael J; Peterson, Eric D; Hernandez, Adrian F
    To examine the association between warfarin treatment and longitudinal outcomes after ischemic stroke in patients with atrial fibrillation in community practice.Observational study.Hospitals (n = 1487) participating in the Get With The Guidelines (GWTG)-Stroke program in the United States, from 2009 to 2011.12,552 warfarin naive atrial fibrillation patients admitted to hospital for ischemic stroke and treated with warfarin compared with no oral anticoagulant at discharge, linked to Medicare claims for longitudinal outcomes.Major adverse cardiovascular events (MACE) and home time, a patient centered outcomes measure defined as the total number of days free from institutional care after discharge. A propensity score inverse probability weighting method was used to account for all differences in observed characteristics between treatment groups.Among 12,552 survivors of stroke, 11,039 (88%) were treated with warfarin at discharge. Warfarin treated patients were slightly younger and less likely to have a history of previous stroke or coronary artery disease but had similar severity of stroke as measured by the National Institutes of Health Stroke Scale. Relative to those not treated, patients treated with warfarin had more days at home (as opposed to institutional care) during the two years after discharge (adjusted home time difference 47.6 days, 99% confidence interval 26.9 to 68.2). Patients discharged on warfarin treatment also had a reduced risk of MACE (adjusted hazard ratio 0.87, 99% confidence interval 0.78 to 0.98), all cause mortality (0.72, 0.63 to 0.84), and recurrent ischemic stroke (0.63, 0.48 to 0.83). These differences were consistent among clinically relevant subgroups by age, sex, stroke severity, and history of previous coronary artery disease and stroke.Among ischemic stroke patients with atrial fibrillation, warfarin treatment was associated with improved long term clinical outcomes and more days at home. Clinical trial registration Clinical trials NCT02146274.