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Schwamm, Lee

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Schwamm

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Schwamm, Lee
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    Patterns of Anticonvulsant Use and Adverse Drug Events in Older Adults
    (Wiley, 2020-10-02) Moura, Lidia Maria; Smith, Jason R.; Yan, Zhiyu; Blacker, Deborah; Schwamm, Lee; Newhouse, Joseph; Hernandez-Diaz, Sonia; Hsu, John
    Purpose: To examine indications for, duration of use, and rate of adverse drug events (ADE) attributable to anticonvulsant initiation, as adjudicated by expert review of electronic health records (EHR) of older adults. Methods: We identified a cohort of community-dwelling Medicare beneficiaries with linked EHR (aged 65+, continuously enrolled with a large health system/until death between 2012-2014, n=20,945) and drew a stratified EHR review sample (n=1,534). An expert reviewed all records to adjudicate anticonvulsant use, years of use, indication for use, and evidence of ADEs attributable to anticonvulsant initiation. After excluding patients with insufficient EHR data (n=37; 2%), we reconstructed the cohort using inverse probability weights to resemble the original cohort of eligible beneficiaries (n=20,380). Among incident users of a single anticonvulsant, we estimated the rate of ADEs and described the type and severity of ADEs. Results: Overall, 12% (n=2,469) of eligible beneficiaries used at least one anticonvulsant in the 2012-2014 period (4% [n=757] incident users, 8% [n=1,712] prevalent users). Incident users were most frequently prescribed gabapentin (n=461/757, 61%), benzodiazepines (n=122/757, 16%), and levetiracetam (n=74/757, 10%); the most common indication was pain relief (n=214; 28%) followed by epilepsy (n=53; 7%). Among incident users, the overall ADE rate was 10/100 person-years (95% CI 4-20/100 person-years), of which 29% (n=28/97) were life-threatening (e.g., somnolence). Most ADEs among incident monotherapy users were nervous-system related (68%, n=66/97). Conclusions: Many older adult community-dwelling Traditional Medicare beneficiaries had clinically significant ADEs likely attributable to the initiation of anticonvulsant therapy, which was begun for a range of indications.
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    Neuroimaging Paradigms to Identify Patients for Reperfusion Therapy in Stroke of Unknown Onset
    (Frontiers Media S.A., 2018) Etherton, Mark; Barreto, Andrew D.; Schwamm, Lee; Wu, Ona
    Despite the proven efficacy of intravenous alteplase or endovascular thrombectomy for the treatment of patients with acute ischemic stroke, only a minority receive these treatments. This low treatment rate is due in large part to delay in hospital arrival or uncertainty as to the exact time of onset of ischemic stroke, which renders patients outside the current guideline-recommended window of eligibility for receiving these therapeutics. However, recent pivotal clinical trials of late-window thrombectomy now force us to rethink the value of a simplistic chronological formulation that “time is brain.” We must recognize a more nuanced concept that the rate of tissue death as a function of time is not invariant, that still salvageable tissue at risk of infarction may be present up to 24 h after last-known well, and that those patients may strongly benefit from reperfusion. Multiple studies have sought to address this clinical dilemma using neuroimaging methods to identify a radiographic time-stamp of stroke onset or evidence of salvageable ischemic tissue and thereby increase the number of patients eligible for reperfusion therapies. In this review, we provide a critical analysis of the current state of neuroimaging techniques to select patients with unwitnessed stroke for revascularization therapies and speculate on the future direction of this clinically relevant area of stroke research.
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    Professional Medical Interpreters Influence the Quality of Acute Ischemic Stroke Care for Patients Who Speak Languages Other than English
    (John Wiley and Sons Inc., 2017) Luan Erfe, Betty M.; Siddiqui, Khawja A.; Schwamm, Lee; Kirwan, Chris; Nunes, Anabela; Mejia, Nicte
    Background: The inability to communicate effectively in a common language can jeopardize clinicians’ efforts to provide quality patient care. Professional medical interpreters (PMIs) can help provide linguistically appropriate health care, in particular for the >25 million Americans who identify speaking English less than very well. We aimed to evaluate the relationship between use of PMIs and quality of acute ischemic stroke care received by patients who preferred to have their medical care in languages other than English. Methods and Results: We analyzed data from 259 non–English‐preferring acute ischemic stroke patients who participated in the American Heart Association Get With The Guidelines–Stroke program at our hospital from January 1, 2003, to April 30, 2014. We used descriptive statistics and logistic regression models to examine associations between involvement of PMIs and patients’ receipt of defect‐free stroke care. A total of 147 of 259 (57%) non–English‐preferring patients received PMI services during their hospital stays. Multivariable analyses adjusting for other socioeconomic factors showed that acute ischemic stroke patients who did not receive PMIs had lower odds of receiving defect‐free stroke care (odds ratio: 0.52; P=0.04). Conclusions: Our findings suggest that PMIs may influence the quality of acute ischemic stroke care.
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    Healthcare Resource Availability, Quality of Care, and Acute Ischemic Stroke Outcomes
    (John Wiley and Sons Inc., 2017) O'Brien, Emily C.; Wu, Jingjing; Zhao, Xin; Schulte, Phillip J.; Fonarow, Gregg C.; Hernandez, Adrian F.; Schwamm, Lee; Peterson, Eric D.; Bhatt, Deepak; Smith, Eric E.
    Background: Healthcare resources vary geographically, but associations between hospital‐based resources and acute stroke quality and outcomes remain unclear. Methods and Results: Using Get With The Guidelines‐Stroke and Dartmouth Atlas of Health Care data, we examined associations between healthcare resource availability, stroke care, and outcomes. We categorized hospital referral regions with high‐, medium‐, or low‐resource levels based on the 2006 national per‐capita availability median of 6 relevant acute stroke care resources. Using multivariable logistic regression, we examined healthcare resource level and in‐hospital quality and outcomes. Of 1 480 308 admitted ischemic stroke patients (2006–2013), 28.8% were hospitalized in low‐, 44.4% in medium‐, and 26.9% in high‐resource hospital referral regions. Quality‐of‐care/timeliness metrics, adjusted length of stay, and in‐hospital mortality were similar across all resource levels. Conclusions: Significant variation exists in regional availability of healthcare resources for acute ischemic stroke treatment, yet among Get With the Guidelines‐Stroke hospitals, quality of care and in‐hospital outcomes did not differ by regional resource availability.
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    Hospital Acquired Pneumonia Is Linked to Right Hemispheric Peri-Insular Stroke
    (Public Library of Science, 2013) Kemmling, André; Lev, Michael; Payabvash, Seyedmehdi; Betensky, Rebecca; Qian, Jing; Masrur, Shihab; Schwamm, Lee
    Purpose Hospital acquired pneumonia (HAP) is a major complication of stroke. We sought to determine associations between infarction of specific brain regions and HAP. Methods: 215 consecutive acute stroke patients with HAP (2003–2009) were carefully matched with 215 non-pneumonia controls by gender, then NIHSS, then age. Admission imaging and binary masks of infarction were registered to MNI-152 space. Regional atlas and voxel-based log-odds were calculated to assess the relationship between infarct location and the likelihood of HAP. An independently validated penalized conditional logistic regression model was used to identify HAP associated imaging regions. Results: The HAP and control patients were well matched by gender (100%), age (95% within 5-years), NIHSS (98% within 1-point), infarct size, dysphagia, and six other clinical variables. Right hemispheric infarcts were more frequent in patients with HAP versus controls (43.3% vs. 34.0%, p = 0.054), whereas left hemispheric infarcts were more frequent in controls (56.7% vs. 44.7%, p = 0.012); there was no significant difference between groups in the rate of brainstem strokes (p = 1.0). Of the 10 most infarcted regions, only right insular cortex volume was different in HAP versus controls (20 vs. 12 ml, p = 0.02). In univariate analyses, the highest log-odds regions for pneumonia were right hemisphere, cerebellum, and brainstem. The best performing multivariate model selected 7 brain regions of infarction and 2 infarct volume-based variables independently associated with HAP. Conclusions: HAP is associated with right hemispheric peri-insular stroke. These associations may be related to autonomic modulation of immune mechanisms, supporting recent hypotheses of stroke mediated immune suppression.
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    Paradoxical Association of Smoking With In‐Hospital Mortality Among Patients Admitted With Acute Ischemic Stroke
    (Blackwell Publishing Ltd, 2013) Ali, Syed F.; Smith, Eric E.; Bhatt, Deepak L.; Fonarow, Gregg C.; Schwamm, Lee
    Background: Compared to those who never smoked, a paradoxical effect of smoking on reducing mortality in patients admitted with myocardial ischemia has been reported. We sought to determine if this effect was present in patients hospitalized with ischemic stroke. Methods and Results: Using the local Get with the Guidelines‐Stroke registry, we analyzed 4305 consecutively admitted ischemic stroke patients (March 2002–December 2011). The sample was divided into smokers versus nonsmokers. The main outcome of interest was the overall inpatient mortality. Compared to nonsmokers, tobacco smokers were younger, more frequently male and presented with fewer stroke risk factors such as hypertension, hyperlipidemia, diabetes, coronary artery disease, and atrial fibrillation. Smokers also had a lower average NIH Stroke Scale (NIHSS) and fewer received tissue plasminogen activator (tPA). Patients in both groups had similar adherence to early antithrombotics, dysphagia screening prior to oral intake, and deep vein thrombosis (DVT) prophylaxis. Smoking was associated with lower all‐cause in‐hospital mortality (6.6% versus 12.4%; unadjusted OR 0.46; CI [0.34 to 0.63]; P<0.001). In multivariable analysis, adjusted for age, gender, ethnicity, hypertension, diabetes mellitus, hyperlipidemia, CAD, atrial fibrillation, NIHSS, and tPA, smoking remained independently associated with lower mortality (adjusted OR 0.64; CI [0.42 to 0.96]; P=0.03). Conclusions: Similar to myocardial ischemia, smoking was independently associated with lower inpatient mortality in acute ischemic stroke. This effect may be due to tobacco‐induced changes in cerebrovascular vasoreactivity, or may be due in part to residual confounding. Larger, multicenter studies are needed to confirm the finding and the effect on 30‐day and 1‐year mortality.
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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 Publishing Group Ltd., 2015) Xian, Ying; Wu, Jingjing; O’Brien, Emily C; Fonarow, Gregg C; Olson, DaiWai M; Schwamm, Lee; Bhatt, Deepak; 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
    Objective To examine the association between warfarin treatment and longitudinal outcomes after ischemic stroke in patients with atrial fibrillation in community practice. Design: Observational study. Setting: Hospitals (n=1487) participating in the Get With The Guidelines (GWTG)-Stroke program in the United States, from 2009 to 2011. Participants: 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. Main outcome measures 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. Results: 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. Conclusions: 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.
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    An International Standard Set of Patient-Centered Outcome Measures After Stroke
    (Lippincott Williams & Wilkins, 2015) Salinas, Joel; Sprinkhuizen, Sara M.; Ackerson, Teri; Bernhardt, Julie; Davie, Charlie; George, Mary G.; Gething, Stephanie; Kelly, Adam G.; Lindsay, Patrice; Liu, Liping; Martins, Sheila C.O.; Morgan, Louise; Norrving, Bo; Ribbers, Gerard M.; Silver, Frank L.; Smith, Eric E.; Williams, Linda S.; Schwamm, Lee
    Background and Purpose— Value-based health care aims to bring together patients and health systems to maximize the ratio of quality over cost. To enable assessment of healthcare value in stroke management, an international standard set of patient-centered stroke outcome measures was defined for use in a variety of healthcare settings. Methods— A modified Delphi process was implemented with an international expert panel representing patients, advocates, and clinical specialists in stroke outcomes, stroke registers, global health, epidemiology, and rehabilitation to reach consensus on the preferred outcome measures, included populations, and baseline risk adjustment variables. Results— Patients presenting to a hospital with ischemic stroke or intracerebral hemorrhage were selected as the target population for these recommendations, with the inclusion of transient ischemic attacks optional. Outcome categories recommended for assessment were survival and disease control, acute complications, and patient-reported outcomes. Patient-reported outcomes proposed for assessment at 90 days were pain, mood, feeding, selfcare, mobility, communication, cognitive functioning, social participation, ability to return to usual activities, and health-related quality of life, with mobility, feeding, selfcare, and communication also collected at discharge. One instrument was able to collect most patient-reported subdomains (9/16, 56%). Minimum data collection for risk adjustment included patient demographics, premorbid functioning, stroke type and severity, vascular and systemic risk factors, and specific treatment/care-related factors. Conclusions— A consensus stroke measure Standard Set was developed as a simple, pragmatic method to increase the value of stroke care. The set should be validated in practice when used for monitoring and comparisons across different care settings.
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    The TeleStroke Mimic (TM)‐Score: A Prediction Rule for Identifying Stroke Mimics Evaluated in a Telestroke Network
    (Blackwell Publishing Ltd, 2014) Ali, Syed F.; Viswanathan, Anand; Singhal, Aneesh; Rost, Natalia S.; Forducey, Pamela G.; Davis, Lawrence W.; Schindler, Joseph; Likosky, William; Schlegel, Sherene; Solenski, Nina; Schwamm, Lee
    Background: Up to 30% of acute stroke evaluations are deemed stroke mimics (SM). As telestroke consultation expands across the world, increasing numbers of SM patients are likely being evaluated via Telestroke. We developed a model to prospectively identify ischemic SMs during Telestroke evaluation. Methods and Results: We analyzed 829 consecutive patients from January 2004 to April 2013 in our internal New England–based Partners TeleStroke Network for a derivation cohort, and 332 cases for internal validation. External validation was performed on 226 cases from January 2008 to August 2012 in the Partners National TeleStroke Network. A predictive score was developed using stepwise logistic regression, and its performance was assessed using receiver‐operating characteristic (ROC) curve analysis. There were 23% SM in the derivation, 24% in the internal, and 22% in external validation cohorts based on final clinical diagnosis. Compared to those with ischemic cerebrovascular disease (iCVD), SM had lower mean age, fewer vascular risk factors, more frequent prior seizure, and a different profile of presenting symptoms. The TeleStroke Mimic Score (TM‐Score) was based on factors independently associated with SM status including age, medical history (atrial fibrillation, hypertension, seizures), facial weakness, and National Institutes of Health Stroke Scale >14. The TM‐Score performed well on ROC curve analysis (derivation cohort AUC=0.75, internal validation AUC=0.71, external validation AUC=0.77). Conclusions: SMs differ substantially from their iCVD counterparts in their vascular risk profiles and other characteristics. Decision‐support tools based on predictive models, such as our TM Score, may help clinicians consider alternate diagnosis and potentially detect SMs during complex, time‐critical telestroke evaluations.
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    Patterns of Care Quality and Prognosis Among Hospitalized Ischemic Stroke Patients With Chronic Kidney Disease
    (Blackwell Publishing Ltd, 2014) Ovbiagele, Bruce; Schwamm, Lee; Smith, Eric E.; Grau‐Sepulveda, Maria V.; Saver, Jeffrey L.; Bhatt, Deepak; Hernandez, Adrian F.; Peterson, Eric D.; Fonarow, Gregg C.
    Background: Relatively little is known about the quality of care and outcomes for hospitalized ischemic stroke patients with chronic kidney disease (CKD). We examined quality of care and in‐hospital prognoses among patients with CKD in the Get With The Guidelines–Stroke (GWTG‐Stroke) program Methods and Results: We analyzed 679 827 patients hospitalized with ischemic stroke from 1564 US centers participating in the GWTG‐Stroke program between January 2009 and December 2012. Use of 7 predefined ischemic stroke performance measures, composite “defect‐free” care compliance, and in‐hospital mortality were examined based on glomerular filtration rate (GFR) categorized as a dichotomous (+CKD as <60) or rank‐ordered variable: normal (≥90), mild (≥60 to <90), moderate (≥30 to <60), severe (≥15 to <30), and kidney failure (<15 or dialysis). There were 236 662 (35%) ischemic stroke patients with CKD. Patients with severe renal dysfunction or failure were significantly less likely to receive guideline‐based therapies. Compared with patients with normal kidney function (≥90), those with CKD (adjusted OR 0.91 [95% CI: 0.89 to 0.92]), moderate dysfunction (adjusted OR 0.94 [95% CI: 0.92 to 0.97]), severe dysfunction (adjusted OR 0.80 [95% CI: 0.77 to 0.84]), or failure (adjusted OR 0.72 [95% CI: 0.68 to 0.0.76]), were less likely to receive 100% defect‐free care measure compliance. Inpatient mortality was higher for patients with CKD (adjusted odds ratio 1.44 [95% CI: 1.40 to 1.47]), and progressively rose with more severe renal dysfunction. Conclusions: Despite higher in‐hospital mortality rates, ischemic stroke patients with CKD, especially those with greater severity of renal dysfunction, were less likely to receive important guideline‐recommended therapies.