Browsing by Author "Schwamm, Lee"

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    Absence of July Phenomenon in Acute Ischemic Stroke Care Quality and Outcomes.
    (Journal of the American Heart Association, 2018-01-31) Gonzalez-Castellon, Marco; Ju, Christine; Xian, Ying; Hernandez, Adrian; Fonarow, Gregg C; Schwamm, Lee; Smith, Eric E; Bhatt, Deepak L; Reeves, Matthew; Willey, Joshua Z
    BACKGROUND:Lower care quality and an increase in adverse outcomes as a result of new medical trainees is a concept well rooted in popular belief, termed the "July phenomenon." Whether this phenomenon occurs in acute ischemic stroke has not been well studied. METHODS AND RESULTS:We analyzed data from patients admitted with ischemic stroke in 1625 hospitals participating in the Get With The Guidelines-Stroke program for the 5-year period between January 2009 and December 2013. We compared acute stroke treatment processes and in-hospitals outcomes among the 4 quarters (first quarter: July-September, last quarter: April-June) of the academic year. Multivariable logistic regression models were used to evaluate the relationship between academic year transition and processes measures. A total of 967 891 patients were included in the study. There was a statistically significant, but modest (<4 minutes or 5 percentage points) difference in distribution of or quality and clinical metrics including door-to-computerized tomography time, door-to-needle time, the proportion of patients with symptomatic intracranial hemorrhage within 36 hours of admission, and the proportion of patients who received defect-free care in stroke performance measures among academic year quarters (P<0.0001). In multivariable analyses, there was no evidence that quarter 1 of the academic year was associated with lower quality of care or worse in-hospital outcomes in teaching and nonteaching hospitals. CONCLUSIONS:We found no evidence of the "July phenomenon" in patients with acute ischemic stroke among hospitals participating in the Get With The Guidelines-Stroke program.
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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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    Probing the Effective Treatment Thresholds for Alteplase in Acute Ischemic Stroke With Regression Discontinuity Designs.
    (Frontiers in neurology, 2020-01) Naidech, Andrew M; Lawlor, Patrick N; Xu, Haolin; Fonarow, Gregg C; Xian, Ying; Smith, Eric E; Schwamm, Lee; Matsouaka, Roland; Prabhakaran, Shyam; Marinescu, Ioana; Kording, Konrad P
    Randomized Controlled Trials (RCTs) are considered the gold standard for measuring the efficacy of medical interventions. However, RCTs are expensive, and use a limited population. Techniques to estimate the effects of stroke interventions from observational data that minimize confounding would be useful. We used regression discontinuity design (RDD), a technique well-established in economics, on the Get With The Guidelines-Stroke (GWTG-Stroke) data set. RDD, based on regression, measures the occurrence of a discontinuity in an outcome (e.g., odds of home discharge) as a function of an intervention (e.g., alteplase) that becomes significantly more likely when crossing the threshold of a continuous variable that determines that intervention (e.g., time from symptom onset, since alteplase is only given if symptom onset is less than e.g., 3 h). The technique assumes that patients near either side of a threshold (e.g., 2.99 and 3.01 h from symptom onset) are indistinguishable other than the use of the treatment. We compared outcomes of patients whose estimated onset to treatment time fell on either side of the treatment threshold for three cohorts of patients in the GWTG-Stroke data set. This data set spanned three different treatment thresholds for alteplase (3 h, 2003-2007, N = 1,869; 3 h, 2009-2016, N = 13,086, and 4.5 h, 2009-2016, N = 6,550). Patient demographic characteristics were overall similar across the treatment thresholds. We did not find evidence of a discontinuity in clinical outcome at any treatment threshold attributable to alteplase. Potential reasons for failing to find an effect include violation of some RDD assumptions in clinical care, large sample sizes required, or already-well-chosen treatment threshold.
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    Temperature and Precipitation Associate With Ischemic Stroke Outcomes in the United States.
    (Journal of the American Heart Association, 2018-11) Chu, Stacy Y; Cox, Margueritte; Fonarow, Gregg C; Smith, Eric E; Schwamm, Lee; Bhatt, Deepak L; Matsouaka, Roland A; Xian, Ying; Sheth, Kevin N
    Background There is disagreement in the literature about the relationship between strokes and seasonal conditions. We sought to (1) describe seasonal patterns of stroke in the United States, and (2) determine the relationship between weather variables and stroke outcomes. Methods and Results We performed a cross-sectional study using Get With The Guidelines-Stroke data from 896 hospitals across the continental United States. We examined effects of season, climate region, and climate variables on stroke outcomes. We identified 457 638 patients admitted from 2011 to 2015 with ischemic stroke. There was a higher frequency of admissions in winter (116 862 in winter versus 113 689 in spring, 113 569 in summer, and 113 518 in fall; P<0.0001). Winter was associated with higher odds of in-hospital mortality (odds ratio [OR] 1.08 relative to spring, confidence interval [ CI ] 1.04-1.13, P=0.0004) and lower odds of discharge home ( OR 0.92, CI 0.91-0.94, P<0.0001) or independent ambulation at discharge ( OR 0.96, CI 0.94-0.98, P=0.0006). These differences were attenuated after adjusting for climate region and case mix and became inconsistent after controlling for weather variables. Temperature and precipitation were independently associated with outcome after multivariable analysis, with increases in temperature and precipitation associated with lower odds of mortality ( OR 0.95, CI 0.93-0.97, P<0.0001 and OR 0.95, CI 0.90-1.00, P=0.035, respectively). Conclusions Admissions for ischemic stroke were more frequent in the winter. Warmer and wetter weather conditions were independently associated with better outcomes. Further studies should aim to identify sensitive populations and inform public health measures aimed at resource allocation, readiness, and adaptive strategies.
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    Time to Anticoagulation Reversal and Outcomes After Intracerebral Hemorrhage.
    (JAMA neurology, 2024-02) Sheth, Kevin N; Solomon, Nicole; Alhanti, Brooke; Messe, Steven R; Xian, Ying; Bhatt, Deepak L; Hemphill, J Claude; Frontera, Jennifer A; Chang, Raymond C; Danelich, Ilya M; Huang, Joanna; Schwamm, Lee; Smith, Eric E; Goldstein, Joshua N; Mac Grory, Brian; Fonarow, Gregg C; Saver, Jeffrey L

    Importance

    Intracerebral hemorrhage (ICH) is the deadliest stroke subtype, and mortality rates are especially high in anticoagulation-associated ICH. Recently, specific anticoagulation reversal strategies have been developed, but it is not clear whether there is a time-dependent treatment effect for door-to-treatment (DTT) times in clinical practice.

    Objective

    To evaluate whether DTT time is associated with outcome among patients with anticoagulation-associated ICH treated with reversal interventions.

    Design, setting, and participants

    This cohort study used data from the American Heart Association Get With The Guidelines-Stroke quality improvement registry. Patients with ICH who presented within 24 hours of symptom onset across 465 US hospitals from 2015 to 2021 were included. Data were analyzed from January to September 2023.

    Exposures

    Anticoagulation-associated ICH.

    Main outcomes and measures

    DTT times and outcomes were analyzed using logistic regression modeling, adjusted for demographic, history, baseline, and hospital characteristics, with hospital-specific random intercepts to account for clustering by site. The primary outcome of interest was the composite inpatient mortality and discharge to hospice. Additional prespecified secondary outcomes, including functional outcome (discharge modified Rankin Scale score, ambulatory status, and discharge venue), were also examined.

    Results

    Of 9492 patients with anticoagulation-associated ICH and documented reversal intervention status, 4232 (44.6%) were female, and the median (IQR) age was 77 (68-84) years. A total of 7469 (78.7%) received reversal therapy, including 4616 of 5429 (85.0%) taking warfarin and 2856 of 4069 (70.2%) taking a non-vitamin K antagonist oral anticoagulant. For the 5224 patients taking a reversal intervention with documented workflow times, the median (IQR) onset-to-treatment time was 232 (142-482) minutes and the median (IQR) DTT time was 82 (58-117) minutes, with a DTT time of 60 minutes or less in 1449 (27.7%). A DTT time of 60 minutes or less was associated with decreased mortality and discharge to hospice (adjusted odds ratio, 0.82; 95% CI, 0.69-0.99) but no difference in functional outcome (ie, a modified Rankin Scale score of 0 to 3; adjusted odds ratio, 0.91; 95% CI, 0.67-1.24). Factors associated with a DTT time of 60 minutes or less included White race, higher systolic blood pressure, and lower stroke severity.

    Conclusions and relevance

    In US hospitals participating in Get With The Guidelines-Stroke, earlier anticoagulation reversal was associated with improved survival for patients with ICH. These findings support intensive efforts to accelerate evaluation and treatment for patients with this devastating form of stroke.