Browsing by Author "Matsouaka, Roland A"
Now showing 1 - 20 of 23
Results Per Page
Sort Options
Item Open Access A Study of Practice Behavior for Endotracheal Intubation Site for Children With Congenital Heart Disease Undergoing Surgery: Impact of Endotracheal Intubation Site on Perioperative Outcomes-An Analysis of the Society of Thoracic Surgeons Congenital Cardiac Anesthesia Society Database.(Anesthesia and analgesia, 2018-09-05) Greene, Nathaniel H; Jooste, Edmund H; Thibault, Dylan P; Wallace, Amelia S; Wang, Alice; Vener, David F; Matsouaka, Roland A; Jacobs, Marshall L; Jacobs, Jeffrey P; Hill, Kevin D; Ames, Warwick AIn adults undergoing cardiopulmonary bypass surgery, oral intubation is typically preferred over nasal intubation due to reduced risk of sinusitis and infection. In children, nasal intubation is more common and sometimes preferred due to perceived benefits of less postoperative sedation and a lower risk for accidental extubation. This study sought to describe the practice of nasal intubation in the pediatric population undergoing cardiopulmonary bypass surgery and assess the risks/benefits of a nasal route against an oral one.Patients <18 years of age in the Society of Thoracic Surgeons Congenital Heart Surgery Database between January 2010 and December 2015 were included. Patients with a preoperative endotracheal tube, tracheostomy, or known airway anomalies were excluded. Multivariable modeling was used to assess the association between route of tracheal intubation and a composite measure of infection risk (wound infection, mediastinitis, septicemia, pneumonia, and endocarditis). Covariates were included to adjust for important patient characteristics (eg, weight, age, comorbidities), case complexity, and center effects. Secondary outcomes included length of intubation, hospital length of stay, and airway complications including accidental extubations. We also performed a subanalysis in children <12 months of age in high-volume centers (>100 cases/y) examining how infection risk may change with age at the time of surgery.Nasal intubation was used in 41% of operations in neonates, 38% in infants, 15% in school-aged children, and 2% in adolescents. Nasal intubation appeared protective for accidental extubation only in neonates (P = .02). Multivariable analysis in infants and neonates showed that the nasal route of intubation was not associated with the infection composite (relative risk [RR], 0.84; 95% CI, 0.59-1.18) or a shorter length of stay (RR, 0.992; 95% CI, 0.947-1.039), but was associated with a shorter intubation length (RR, 0.929; 95% CI, 0.869-0.992). Restricting to high-volume centers showed a significant interaction between age and intubation route with a risk change for infection occurring between approximately 6-12 months of age (P = .003).While older children undergoing nasal intubation trend similar to the adult population with an increased risk of infection, nasal intubation in neonates and infants does not appear to carry a similar risk. Nasal intubation in neonates and infants may also be associated with a shorter intubation length but not a shorter length of stay. Prospective studies are required to better understand these complex associations.Item Open Access An optimal Wilcoxon-Mann-Whitney test of mortality and a continuous outcome.(Stat Methods Med Res, 2016-01-01) Matsouaka, Roland A; Singhal, Aneesh B; Betensky, Rebecca AWe consider a two-group randomized clinical trial, where mortality affects the assessment of a follow-up continuous outcome. Using the worst-rank composite endpoint, we develop a weighted Wilcoxon-Mann-Whitney test statistic to analyze the data. We determine the optimal weights for the Wilcoxon-Mann-Whitney test statistic that maximize its power. We derive a formula for its power and demonstrate its accuracy in simulations. Finally, we apply the method to data from an acute ischemic stroke clinical trial of normobaric oxygen therapy.Item Open Access Association Between Thrombolytic Door-to-Needle Time and 1-Year Mortality and Readmission in Patients With Acute Ischemic Stroke.(JAMA, 2020-06) Man, Shumei; Xian, Ying; Holmes, DaJuanicia N; Matsouaka, Roland A; Saver, Jeffrey L; Smith, Eric E; Bhatt, Deepak L; Schwamm, Lee H; Fonarow, Gregg CImportance:Earlier administration of intravenous tissue plasminogen activator (tPA) in acute ischemic stroke is associated with reduced mortality by the time of hospital discharge and better functional outcomes at 3 months. However, it remains unclear whether shorter door-to-needle times translate into better long-term outcomes. Objective:To examine whether shorter door-to-needle times with intravenous tPA for acute ischemic stroke are associated with improved long-term outcomes. Design, Setting, and Participants:This retrospective cohort study included Medicare beneficiaries aged 65 years or older who were treated for acute ischemic stroke with intravenous tPA within 4.5 hours from the time they were last known to be well at Get With The Guidelines-Stroke participating hospitals between January 1, 2006, and December 31, 2016, with 1-year follow-up through December 31, 2017. Exposures:Door-to-needle times for intravenous tPA. Main Outcomes and Measures:The primary outcomes were 1-year all-cause mortality, all-cause readmission, and the composite of all-cause mortality or readmission. Results:Among the 61 426 patients treated with tPA within 4.5 hours, the median age was 80 years and 43.5% were male. The median door-to-needle time was 65 minutes (interquartile range, 49-88 minutes). The 48 666 patients (79.2%) who were treated with tPA and had door-to-needle times of longer than 45 minutes, compared with those treated within 45 minutes, had significantly higher all-cause mortality (35.0% vs 30.8%, respectively; adjusted HR, 1.13 [95% CI, 1.09-1.18]), higher all-cause readmission (40.8% vs 38.4%; adjusted HR, 1.08 [95% CI, 1.05-1.12]), and higher all-cause mortality or readmission (56.0% vs 52.1%; adjusted HR, 1.09 [95% CI, 1.06-1.12]). The 34 367 patients (55.9%) who were treated with tPA and had door-to-needle times of longer than 60 minutes, compared with those treated within 60 minutes, had significantly higher all-cause mortality (35.8% vs 32.1%, respectively; adjusted hazard ratio [HR], 1.11 [95% CI, 1.07-1.14]), higher all-cause readmission (41.3% vs 39.1%; adjusted HR, 1.07 [95% CI, 1.04-1.10]), and higher all-cause mortality or readmission (56.8% vs 53.1%; adjusted HR, 1.08 [95% CI, 1.05-1.10]). Every 15-minute increase in door-to-needle times was significantly associated with higher all-cause mortality (adjusted HR, 1.04 [95% CI, 1.02-1.05]) within 90 minutes after hospital arrival, but not after 90 minutes (adjusted HR, 1.01 [95% CI, 0.99-1.03]), higher all-cause readmission (adjusted HR, 1.02; 95% CI, 1.01-1.03), and higher all-cause mortality or readmission (adjusted HR, 1.02 [95% CI, 1.01-1.03]). Conclusions and Relevance:Among patients aged 65 years or older with acute ischemic stroke who were treated with tissue plasminogen activator, shorter door-to-needle times were associated with lower all-cause mortality and lower all-cause readmission at 1 year. These findings support efforts to shorten time to thrombolytic therapy.Item Open Access Association Between Time to Treatment With Endovascular Reperfusion Therapy and Outcomes in Patients With Acute Ischemic Stroke Treated in Clinical Practice.(JAMA, 2019-07) Jahan, Reza; Saver, Jeffrey L; Schwamm, Lee H; Fonarow, Gregg C; Liang, Li; Matsouaka, Roland A; Xian, Ying; Holmes, DaJuanicia N; Peterson, Eric D; Yavagal, Dileep; Smith, Eric EImportance:Randomized clinical trials suggest benefit of endovascular-reperfusion therapy for large vessel occlusion in acute ischemic stroke (AIS) is time dependent, but the extent to which it influences outcome and generalizability to routine clinical practice remains uncertain. Objective:To characterize the association of speed of treatment with outcome among patients with AIS undergoing endovascular-reperfusion therapy. Design, Setting, and Participants:Retrospective cohort study using data prospectively collected from January 2015 to December 2016 in the Get With The Guidelines-Stroke nationwide US quality registry, with final follow-up through April 15, 2017. Participants were 6756 patients with anterior circulation large vessel occlusion AIS treated with endovascular-reperfusion therapy with onset-to-puncture time of 8 hours or less. Exposures:Onset (last-known well time) to arterial puncture, and hospital arrival to arterial puncture (door-to-puncture time). Main Outcomes and Measures:Substantial reperfusion (modified Thrombolysis in Cerebral Infarction score 2b-3), ambulatory status, global disability (modified Rankin Scale [mRS]) and destination at discharge, symptomatic intracranial hemorrhage (sICH), and in-hospital mortality/hospice discharge. Results:Among 6756 patients, the mean (SD) age was 69.5 (14.8) years, 51.2% (3460/6756) were women, and median pretreatment score on the National Institutes of Health Stroke Scale was 17 (IQR, 12-22). Median onset-to-puncture time was 230 minutes (IQR, 170-305) and median door-to-puncture time was 87 minutes (IQR, 62-116), with substantial reperfusion in 85.9% (5433/6324) of patients. Adverse events were sICH in 6.7% (449/6693) of patients and in-hospital mortality/hospice discharge in 19.6% (1326/6756) of patients. At discharge, 36.9% (2132/5783) ambulated independently and 23.0% (1225/5334) had functional independence (mRS 0-2). In onset-to-puncture adjusted analysis, time-outcome relationships were nonlinear with steeper slopes between 30 to 270 minutes than 271 to 480 minutes. In the 30- to 270-minute time frame, faster onset to puncture in 15-minute increments was associated with higher likelihood of achieving independent ambulation at discharge (absolute increase, 1.14% [95% CI, 0.75%-1.53%]), lower in-hospital mortality/hospice discharge (absolute decrease, -0.77% [95% CI, -1.07% to -0.47%]), and lower risk of sICH (absolute decrease, -0.22% [95% CI, -0.40% to -0.03%]). Faster door-to-puncture times were similarly associated with improved outcomes, including in the 30- to 120-minute window, higher likelihood of achieving discharge to home (absolute increase, 2.13% [95% CI, 0.81%-3.44%]) and lower in-hospital mortality/hospice discharge (absolute decrease, -1.48% [95% CI, -2.60% to -0.36%]) for each 15-minute increment. Conclusions and Relevance:Among patients with AIS due to large vessel occlusion treated in routine clinical practice, shorter time to endovascular-reperfusion therapy was significantly associated with better outcomes. These findings support efforts to reduce time to hospital and endovascular treatment in patients with stroke.Item Open Access Association of Intracerebral Hemorrhage Among Patients Taking Non-Vitamin K Antagonist vs Vitamin K Antagonist Oral Anticoagulants With In-Hospital Mortality.(JAMA, 2018-02) Inohara, Taku; Xian, Ying; Liang, Li; Matsouaka, Roland A; Saver, Jeffrey L; Smith, Eric E; Schwamm, Lee H; Reeves, Mathew J; Hernandez, Adrian F; Bhatt, Deepak L; Peterson, Eric D; Fonarow, Gregg CAlthough non-vitamin K antagonist oral anticoagulants (NOACs) are increasingly used to prevent thromboembolic disease, there are limited data on NOAC-related intracerebral hemorrhage (ICH).To assess the association between preceding oral anticoagulant use (warfarin, NOACs, and no oral anticoagulants [OACs]) and in-hospital mortality among patients with ICH.Retrospective cohort study of 141 311 patients with ICH admitted from October 2013 to December 2016 to 1662 Get With The Guidelines-Stroke hospitals.Anticoagulation therapy before ICH, defined as any use of OACs within 7 days prior to hospital arrival.In-hospital mortality.Among 141 311 patients with ICH (mean [SD] age, 68.3 [15.3] years; 48.1% women), 15 036 (10.6%) were taking warfarin and 4918 (3.5%) were taking NOACs preceding ICH, and 39 585 (28.0%) and 5783 (4.1%) were taking concomitant single and dual antiplatelet agents, respectively. Patients with prior use of warfarin or NOACs were older and had higher prevalence of atrial fibrillation and prior stroke. Acute ICH stroke severity (measured by the National Institutes of Health Stroke Scale) was not significantly different across the 3 groups (median, 9 [interquartile range, 2-21] for warfarin, 8 [2-20] for NOACs, and 8 [2-19] for no OACs). The unadjusted in-hospital mortality rates were 32.6% for warfarin, 26.5% for NOACs, and 22.5% for no OACs. Compared with patients without prior use of OACs, the risk of in-hospital mortality was higher among patients with prior use of warfarin (adjusted risk difference [ARD], 9.0% [97.5% CI, 7.9% to 10.1%]; adjusted odds ratio [AOR], 1.62 [97.5% CI, 1.53 to 1.71]) and higher among patients with prior use of NOACs (ARD, 3.3% [97.5% CI, 1.7% to 4.8%]; AOR, 1.21 [97.5% CI, 1.11-1.32]). Compared with patients with prior use of warfarin, patients with prior use of NOACs had a lower risk of in-hospital mortality (ARD, -5.7% [97.5% CI, -7.3% to -4.2%]; AOR, 0.75 [97.5% CI, 0.69 to 0.81]). The difference in mortality between NOAC-treated patients and warfarin-treated patients was numerically greater among patients with prior use of dual antiplatelet agents (32.7% vs 47.1%; ARD, -15.0% [95.5% CI, -26.3% to -3.8%]; AOR, 0.50 [97.5% CI, 0.29 to 0.86]) than among those taking these agents without prior antiplatelet therapy (26.4% vs 31.7%; ARD, -5.0% [97.5% CI, -6.8% to -3.2%]; AOR, 0.77 [97.5% CI, 0.70 to 0.85]), although the interaction P value (.07) was not statistically significant.Among patients with ICH, prior use of NOACs or warfarin was associated with higher in-hospital mortality compared with no OACs. Prior use of NOACs, compared with prior use of warfarin, was associated with lower risk of in-hospital mortality.Item Open Access Clinical Outcomes With Metformin and Sulfonylurea Therapies Among Patients With Heart Failure and Diabetes.(JACC. Heart failure, 2022-03) Khan, Muhammad Shahzeb; Solomon, Nicole; DeVore, Adam D; Sharma, Abhinav; Felker, G Michael; Hernandez, Adrian F; Heidenreich, Paul A; Matsouaka, Roland A; Green, Jennifer B; Butler, Javed; Yancy, Clyde W; Peterson, Pamela N; Fonarow, Gregg C; Greene, Stephen JObjectives
The authors sought to characterize associations between initiation of metformin and sulfonylurea therapy and clinical outcomes among patients with comorbid heart failure (HF) and diabetes (overall and by ejection fraction [EF] phenotype).Background
Metformin and sulfonylureas are frequently prescribed to patients with diabetes for glycemic control. The impact of these therapies on clinical outcomes among patients with comorbid HF and diabetes is unclear.Methods
The authors evaluated Medicare beneficiaries hospitalized for HF in the Get With The Guidelines-Heart Failure Registry between 2006 and 2014 with diabetes and not prescribed metformin or sulfonylurea before admission. In parallel separate analyses for metformin and sulfonylurea, patients with newly prescribed therapy within 90 days of discharge were compared with patients not prescribed therapy. Multivariable models landmarked at 90 days evaluated associations between prescription of therapy, and mortality and hospitalization for HF (HHF) at 12 months. Negative control (falsification) endpoints included hospitalization for urinary tract infection, hospitalization for gastrointestinal bleed, and influenza vaccination. Prespecified subgroup analyses were stratified by EF ≤40% versus >40%.Results
Of 5,852 patients, 454 (7.8%) were newly prescribed metformin and 504 (8.6%) were newly prescribed sulfonylurea. After adjustment, metformin prescription was independently associated with reduced risk of composite mortality/HHF (HR: 0.81; 95% CI: 0.67-0.98; P = 0.03), but individual components were not statistically significant. Findings among patients with EF >40% accounted for associations with mortality/HHF (HR: 0.68; 95% CI: 0.52-0.90) and HHF (HR: 0.58; 95% CI: 0.40-0.85) endpoints (all P for interaction ≤0.04). After adjustment, sulfonylurea initiation was associated with increased risk of mortality (HR: 1.24; 95% CI: 1.00-1.52; P = 0.045) and HHF (HR: 1.22; 95% CI: 1.00-1.48; P = 0.050) with nominal statistical significance. Associations between sulfonylurea initiation and endpoints were consistent regardless of EF (all P for interaction >0.11). Neither metformin initiation nor sulfonylurea initiation were associated with negative control endpoints.Conclusions
In this population of older U.S. adults hospitalized for HF with comorbid diabetes, metformin initiation was independently associated with substantial improvements in 12-month clinical outcomes, driven by findings among patients with EF >40%. By contrast, sulfonylurea initiation was associated with excess risk of death and HF hospitalization, regardless of EF.Item Open Access Comparison of Clinical Care and In-Hospital Outcomes of Asian American and White Patients With Acute Ischemic Stroke.(JAMA neurology, 2019-04) Song, Sarah; Liang, Li; Fonarow, Gregg C; Smith, Eric E; Bhatt, Deepak L; Matsouaka, Roland A; Xian, Ying; Schwamm, Lee H; Saver, Jeffrey LImportance:Although overall stroke incidence and mortality in the United States is improving, little is known about the characteristics and clinical outcomes of acute ischemic stroke in Asian American individuals. Objective:To compare the characteristics, care, and outcomes of Asian American and white patients with acute ischemic stroke. Design, Setting, Participants:Retrospective analysis of Asian American and white patients admitted with a primary diagnosis of acute ischemic stroke to hospitals participating in the Get With The Guidelines-Stroke (GWTG-Stroke) program between April 1, 2004, and July 31, 2016. The GWTG-Stroke database is a prospectively collected stroke quality improvement registry sponsored by the American Heart Association/American Stroke Association. Main Outcomes and Measures:Multivariable logistic regression models assessed the association of Asian American race/ethnicity, clinical outcomes, and quality measures. Results:The study population of 1 772 299 patients (mean [SD] age, 72.4 [14.2] years; 51.3% female) consisted of 64 337 Asian American patients (3.6%) and 1 707 962 white patients (96.4%) admitted to 2171 GWTG-Stroke hospitals with acute ischemic stroke. After adjustment for patient and hospital variables, Asian American patients were seen with greater stroke severity compared with white patients (National Institutes of Health Stroke Scale [NIHSS] score ≥16) (odds ratio [OR], 1.35; 95% CI, 1.30-1.40; P < .001), manifested higher in-hospital mortality (OR, 1.14; 95% CI, 1.09-1.19; P < .001), had longer length of stay (OR, 1.17; 95% CI, 1.14-1.20; P < .001), and were less likely to ambulate independently at discharge (OR, 0.84; 95% CI, 0.79-0.90; P < .001). Although Asian American patients had fewer intravenous tissue plasminogen activator (IV tPA) administrations than white patients (OR, 0.95; 95% CI, 0.91-0.98; P = .003), they had more symptomatic hemorrhage after tPA (OR, 1.36; 95% CI, 1.20-1.55; P < .001) and overall post-tPA complications (OR, 1.31; 95% CI, 1.18-1.46; P < .001). Asian American patients had better quality measure adherence overall than white patients, including rehabilitation (OR, 1.27; 95% CI, 1.18-1.36; P < .001), door to tPA within 60 minutes (OR, 1.14; 95% CI, 1.06-1.22; P < .001), and intensive statin therapy (OR, 1.14; 95% CI, 1.10-1.18; P < .001). After adjustment for stroke severity, Asian American patients had lower in-hospital mortality than white patients (OR, 0.95; 95% CI, 0.91-0.99; P = .008). Conclusions and Relevance:Asian American patients manifested more severe ischemic strokes, were less likely to receive IV tPA, and had worse functional outcomes than white patients. These findings warrant additional research toward improving clinical outcomes for Asian American patients with acute ischemic stroke.Item Open Access Defining the Need for Causal Inference to Understand the Impact of Social Determinants of Health: A Primer on Behalf of the Consortium for the Holistic Assessment of Risk in Transplantation (CHART).(Annals of surgery open : perspectives of surgical history, education, and clinical approaches, 2023-12) Bhavsar, Nrupen A; Patzer, Rachel E; Taber, David J; Ross-Driscoll, Katie; Deierhoi Reed, Rhiannon; Caicedo-Ramirez, Juan C; Gordon, Elisa J; Matsouaka, Roland A; Rogers, Ursula; Webster, Wendy; Adams, Andrew; Kirk, Allan D; McElroy, Lisa MObjective
This study aims to introduce key concepts and methods that inform the design of studies that seek to quantify the causal effect of social determinants of health (SDOH) on access to and outcomes following organ transplant.Background
The causal pathways between SDOH and transplant outcomes are poorly understood. This is partially due to the unstandardized and incomplete capture of the complex interactions between patients, their neighborhood environments, the tertiary care system, and structural factors that impact access and outcomes. Designing studies to quantify the causal impact of these factors on transplant access and outcomes requires an understanding of the fundamental concepts of causal inference.Methods
We present an overview of fundamental concepts in causal inference, including the potential outcomes framework and direct acyclic graphs. We discuss how to conceptualize SDOH in a causal framework and provide applied examples to illustrate how bias is introduced.Results
There is a need for direct measures of SDOH, increased measurement of latent and mediating variables, and multi-level frameworks for research that examine health inequities across multiple health systems to generalize results. We illustrate that biases can arise due to socioeconomic status, race/ethnicity, and incongruencies in language between the patient and clinician.Conclusions
Progress towards an equitable transplant system requires establishing causal pathways between psychosocial risk factors, access, and outcomes. This is predicated on accurate and precise quantification of social risk, best facilitated by improved organization of health system data and multicenter efforts to collect and learn from it in ways relevant to specialties and service lines.Item Open Access Exploring the Unmet Need in Acute Ischemic Stroke Patients Not Treated With Intravenous Alteplase: The Get With The Guidelines‐Stroke Registry(Stroke: Vascular and Interventional Neurology, 2022-01) Mac Grory, Brian; Xian, Ying; Solomon, Nicole C; Matsouaka, Roland A; Decker‐Palmer, Marquita R; Fonarow, Gregg C; Smith, Eric E; Schwamm, Lee HBackground Early administration of intravenous tissue plasminogen activator (IV alteplase) improves functional outcomes in patients with acute ischemic stroke, yet many patients are not treated with IV alteplase. There is a need to understand the reasons for nontreatment and the short‐ and long‐term outcomes in this patient population. Methods We analyzed patients ≥65 years old with a primary diagnosis of acute ischemic stroke presenting within 24 hours of time last known well (LKW) but not treated with IV alteplase from 1630 Get With The Guidelines‐Stroke hospitals in the United States between January 2016 and December 2016. We report clinical characteristics, reasons for withholding treatment, in‐hospital mortality, and 90‐day and 1‐year outcomes including costs, stratified by time from LKW to presentation (≤4.5, >4.5–6, and >6–24 hours). Results Of 39 760 patients (median age 80 [25th–75th quartiles: 73–87], 56.7% female), 19 391 (48.8%) presented within 4.5 hours of LKW. In those with documented reasons for withholding IV alteplase, the most common reasons were rapid improvement of symptoms (3985/14 782, 27.0%) and mild symptoms (3791/14 782, 25.6%). In 1100 out of 1174 (93.7%) patients presenting in the >3.0‐ to 4.5‐hour time window, the most common reason for not treating was a delay in patient arrival. The most common discharge location for those presenting ≤4.5 hours since LKW was home (8660/19 391, 44.7%). The 90‐day mortality and readmission rates were 18.9% and 23.0% in those presenting ≤4.5 hours since LKW, 19.0% and 22.2% in those presenting between 4.5 and 6 hours, and 19.1% and 23.2% in those presenting between 6 and 24 hours. Median 90‐day total in‐hospital costs remained relatively high at $9471 (Q25–Q75: $5622–$21 356) in patients presenting ≤4.5 hours since LKW. Conclusions Patients within the Get With The Guidelines‐Stroke registry not treated with IV alteplase have a high risk of readmission and mortality and have high total in‐hospital and postdischarge costs. This study may inform future efforts to address the unmet need to improve the scope of IV alteplase delivery along with other aspects of acute ischemic stroke care and, consequently, outcomes in this patient population.Item Open Access Hospital distance, socioeconomic status, and timely treatment of ischemic stroke.(Neurology, 2019-08) Ader, Jeremy; Wu, Jingjing; Fonarow, Gregg C; Smith, Eric E; Shah, Shreyansh; Xian, Ying; Bhatt, Deepak L; Schwamm, Lee H; Reeves, Mathew J; Matsouaka, Roland A; Sheth, Kevin NOBJECTIVE:To determine whether lower socioeconomic status (SES) and longer home to hospital driving time are associated with reductions in tissue plasminogen activator (tPA) administration and timeliness of the treatment. METHODS:We conducted a retrospective observational study using data from the Get With The Guidelines-Stroke Registry (GWTG-Stroke) between January 2015 and March 2017. The study included 118,683 ischemic stroke patients age ≥18 who were transported by emergency medical services to one of 1,489 US hospitals. We defined each patient's SES based on zip code median household income. We calculated the driving time between each patient's home zip code and the hospital where he or she was treated using the Google Maps Directions Application Programing Interface. The primary outcomes were tPA administration and onset-to-arrival time (OTA). Outcomes were analyzed using hierarchical multivariable logistic regression models. RESULTS:SES was not associated with OTA (p = 0.31) or tPA administration (p = 0.47), but was associated with the secondary outcomes of onset-to-treatment time (OTT) (p = 0.0160) and in-hospital mortality (p = 0.0037), with higher SES associated with shorter OTT and lower in-hospital mortality. Driving time was associated with tPA administration (p < 0.001) and OTA (p < 0.0001), with lower odds of tPA (0.83, 0.79-0.88) and longer OTA (1.30, 1.24-1.35) in patients with the longest vs shortest driving time quartiles. Lower SES quintiles were associated with slightly longer driving time quartiles (p = 0.0029), but there was no interaction between the SES and driving time for either OTA (p = 0.1145) or tPA (p = 0.6103). CONCLUSIONS:Longer driving times were associated with lower odds of tPA administration and longer OTA; however, SES did not modify these associations.Item Open Access Hospital Factors Associated With Interhospital Transfer Destination for Stroke in the Northeast United States.(Journal of the American Heart Association, 2020-01) Zachrison, Kori S; Onnela, Jukka-Pekka; Reeves, Mathew J; Hernandez, Adrian; Camargo, Carlos A; Zhao, Xin; Matsouaka, Roland A; Goldstein, Joshua N; Metlay, Joshua P; Schwamm, Lee HBackground We aimed to determine if there is an association between hospital quality and the likelihood of a given hospital being a preferred transfer destination for stroke patients. Methods and Results Data from Medicare claims identified acute ischemic stroke transferred between 394 northeast US hospitals from 2007 to 2011. Hospitals were categorized as transferring (n=136), retaining (n=241), or receiving (n=17) hospitals based on the proportion of acute ischemic stroke encounters transferred or received. We identified all 6409 potential dyads of sending and receiving hospitals, and categorized dyads as connected if ≥5 patients were transferred between the hospitals annually (n=82). We used logistic regression to identify hospital characteristics associated with establishing a connected dyad, exploring the effect of adjusting for different quality measures and outcomes. We also adjusted for driving distance between hospitals, receiving hospital stroke volume, and the number of hospitals in the receiving hospital referral region. The odds of establishing a transfer connection increased when rate of alteplase administration increased at the receiving hospital or decreased at the sending hospital, however this finding did not hold after applying a potential strategy to adjust for clustering. Receiving hospital performance on 90-day home time was not associated with likelihood of transfer connection. Conclusions Among northeast US hospitals, we found that differences in hospital quality, specifically higher levels of alteplase administration, may be associated with increased likelihood of being a transfer destination. Further research is needed to better understand acute ischemic stroke transfer patterns to optimize stroke transfer systems.Item Open Access Impact of Insurance Status on Outcomes and Use of Rehabilitation Services in Acute Ischemic Stroke: Findings From Get With The Guidelines-Stroke.(J Am Heart Assoc, 2016-11-14) Medford-Davis, Laura N; Fonarow, Gregg C; Bhatt, Deepak L; Xu, Haolin; Smith, Eric E; Suter, Robert; Peterson, Eric D; Xian, Ying; Matsouaka, Roland A; Schwamm, Lee HBACKGROUND: Insurance status affects access to care, which may affect health outcomes. The objective was to determine whether patients without insurance or with government-sponsored insurance had worse quality of care or in-hospital outcomes in acute ischemic stroke. METHODS AND RESULTS: Multivariable logistic regressions with generalized estimating equations stratified by age under or at least 65 years were adjusted for patient demographics and comorbidities, presenting factors, and hospital characteristics to determine differences in in-hospital mortality and postdischarge destination. We included 589 320 ischemic stroke patients treated at 1604 US hospitals participating in the Get With The Guidelines-Stroke program between 2012 and 2015. Uninsured patients with hypertension, high cholesterol, or diabetes mellitus were less likely to be taking appropriate control medications prior to stroke, to use an ambulance to arrive to the ED, or to arrive early after symptom onset. Even after adjustment, the uninsured were more likely than the privately insured to die in the hospital (<65 years, OR 1.33 [95% CI 1.22-1.45]; ≥65 years OR 1.54 [95% CI 1.34-1.75]), and among survivors, were less likely to go to inpatient rehab (<65 OR 0.63 [95% CI 0.6-0.67]; ≥65 OR 0.56 [95% CI 0.5-0.63]). In contrast, patients with Medicare and Medicaid were more likely to be discharged to a Skilled Nursing Facility (<65 years OR 2.08 [CI 1.96-2.2]; OR 2.01 [95% CI 1.91-2.13]; ≥65 years OR 1.1 [95% CI 1.07-1.13]; OR 1.41 [95% CI 1.35-1.46]). CONCLUSIONS: Preventative care prior to ischemic stroke, time to presentation for acute treatment, access to rehabilitation, and in-hospital mortality differ by patient insurance status.Item Open Access International Comparison of Patient Characteristics and Quality of Care for Ischemic Stroke: Analysis of the China National Stroke Registry and the American Heart Association Get With The Guidelines--Stroke Program.(Journal of the American Heart Association, 2018-10) Wangqin, Runqi; Laskowitz, Daniel T; Wang, Yongjun; Li, Zixiao; Wang, Yilong; Liu, Liping; Liang, Li; Matsouaka, Roland A; Saver, Jeffrey L; Fonarow, Gregg C; Bhatt, Deepak L; Smith, Eric E; Schwamm, Lee H; Prvu Bettger, Janet; Hernandez, Adrian F; Peterson, Eric D; Xian, YingBackground Adherence to evidence-based guidelines is an important quality indicator; yet, there is lack of assessment of adherence to performance measures in acute ischemic stroke for most world regions. Methods and Results We analyzed 19 604 patients with acute ischemic stroke in the China National Stroke Registry and 194 876 patients in the Get With The Guidelines--Stroke registry in the United States from June 2012 to January 2013. Compared with their US counterparts, Chinese patients were younger, had a lower prevalence of comorbidities, and had similar median, lower mean, and less variability in National Institutes of Health Stroke Scale (median 4 [25th percentile-75th percentile, 2-7], mean 5.4±5.6 versus median 4 [1-10], mean 6.8±7.7). Chinese patients were more likely to experience delays from last known well to hospital arrival (median 1318 [330-3209] versus 644 [142-2055] minutes), less likely to receive thrombolytic therapy (2.5% versus 8.1%), and more likely to experience treatment delays (door-to-needle time median 95 [72-112] versus 62 [49-85] minutes). Adherence to early and discharge antithrombotics, smoking cessation counseling, and dysphagia screening were relatively high (eg >80%) in both countries. Large gaps existed between China and the United States with regard to the administration of thrombolytics within 3 hours (18.3% versus 83.6%), door-to-needle time ≤60 minutes (14.6% versus 48.0%), deep venous thrombosis prophylaxis (65.0% versus 97.8%), anticoagulation for atrial fibrillation (21.0% versus 94.4%), lipid treatment (66.3% versus 95.8%), and rehabilitation assessment (58.8% versus 97.4%). Conclusions We found significant differences in clinical characteristics and gaps in adherence for certain performance measures between China and the United States. Additional efforts are needed for continued improvements in acute stroke care and secondary prevention in both nations, especially China.Item Open Access Linear regression model with a randomly censored predictor:Estimation procedures(2017-11-01) Atem, Folefac; Matsouaka, Roland AWe consider linear regression model estimation where the covariate of interest is randomly censored. Under a non-informative censoring mechanism, one may obtain valid estimates by deleting censored observations. However, this comes at a cost of lost information and decreased efficiency, especially under heavy censoring. Other methods for dealing with censored covariates, such as ignoring censoring or replacing censored observations with a fixed number, often lead to severely biased results and are of limited practicality. Parametric methods based on maximum likelihood estimation as well as semiparametric and non-parametric methods have been successfully used in linear regression estimation with censored covariates where censoring is due to a limit of detection. In this paper, we adapt some of these methods to handle randomly censored covariates and compare them under different scenarios to recently-developed semiparametric and nonparametric methods for randomly censored covariates. Specifically, we consider both dependent and independent randomly censored mechanisms as well as the impact of using a non-parametric algorithm on the distribution of the randomly censored covariate. Through extensive simulation studies, we compare the performance of these methods under different scenarios. Finally, we illustrate and compare the methods using the Framingham Health Study data to assess the association between low-density lipoprotein (LDL) in offspring and parental age at onset of a clinically-diagnosed cardiovascular event.Item Open Access Management of Atrial Fibrillation in Older Patients by Morbidity Burden: Insights From Get With The Guidelines-Atrial Fibrillation.(Journal of the American Heart Association, 2020-12) Dalgaard, Frederik; Xu, Haolin; Matsouaka, Roland A; Russo, Andrea M; Curtis, Anne B; Rasmussen, Peter Vibe; Ruwald, Martin H; Fonarow, Gregg C; Lowenstern, Angela; Hansen, Morten L; Pallisgaard, Jannik L; Alexander, Karen P; Alexander, John H; Lopes, Renato D; Granger, Christopher B; Lewis, William R; Piccini, Jonathan P; Al-Khatib, Sana MBackground Knowledge is scarce regarding how multimorbidity is associated with therapeutic decisions regarding oral anticoagulants (OACs) in patients with atrial fibrillation. Methods and Results We conducted a cross-sectional study of hospitalized patients with atrial fibrillation using the Get With The Guidelines-Atrial Fibrillation registry from 2013 to 2019. We identified patients ≥65 years and eligible for OAC therapy. Using 16 available comorbidity categories, patients were stratified by morbidity burden. A multivariable logistic regression model was used to determine the odds of receiving OAC prescription at discharge by morbidity burden. We included 34 174 patients with a median (interquartile range) age of 76 (71-83) years, 56.6% women, and 41.9% were not anticoagulated at admission. Of these patients, 38.6% had 0 to 2 comorbidities, 50.7% had 3 to 5 comorbidities, and 10.7% had ≥6 comorbidities. The overall discharge OAC prescription was high (85.6%). The prevalence of patients with multimorbidity increased from 59.7% in 2014 to 64.3% in 2019 (P trend=0.002). Using 0 to 2 comorbidities as the reference, the adjusted odds ratio (95% CI) of OAC prescription were 0.93 (0.82, 1.05) for patients with 3 to 5 comorbidities and 0.72 (0.60, 0.86) for patients with ≥6 comorbidities. In those with ≥6 comorbidities, the most common reason for nonprescription of OACs were frequent falls/frailty (31.0%). Conclusions In a contemporary quality-of-care database of hospitalized patients with atrial fibrillation eligible for OAC therapy, multimorbidity was common. A higher morbidity burden was associated with a lower odds of OAC prescription. This highlights the need for interventions to improve adherence to guideline-recommended anticoagulation in multimorbid patients with atrial fibrillation.Item Open Access Power and sample size calculations for the Wilcoxon-Mann-Whitney test in the presence of death-censored observations.(Stat Med, 2015-02-10) Matsouaka, Roland A; Betensky, Rebecca AWe consider a clinical trial of a potentially lethal disease in which patients are randomly assigned to two treatment groups and are followed for a fixed period of time; a continuous endpoint is measured at the end of follow-up. For some patients; however, death (or severe disease progression) may preclude measurement of the endpoint. A statistical analysis that includes only patients with endpoint measurements may be biased. An alternative analysis includes all randomized patients, with rank scores assigned to the patients who are available for the endpoint measurement on the basis of the magnitude of their responses and with 'worst-rank' scores assigned to those patients whose death precluded the measurement of the continuous endpoint. The worst-rank scores are worse than all observed rank scores. The treatment effect is then evaluated using the Wilcoxon-Mann-Whitney test. In this paper, we derive closed-form formulae for the power and sample size of the Wilcoxon-Mann-Whitney test when missing measurements of the continuous endpoints because of death are replaced by worst-rank scores. We distinguish two approaches for assigning the worst-rank scores. In the tied worst-rank approach, all deaths are weighted equally, and the worst-rank scores are set to a single value that is worse than all measured responses. In the untied worst-rank approach, the worst-rank scores further rank patients according to their time of death, so that an earlier death is considered worse than a later death, which in turn is worse than all measured responses. In addition, we propose four methods for the implementation of the sample size formulae for a trial with expected early death. We conduct Monte Carlo simulation studies to evaluate the accuracy of our power and sample size formulae and to compare the four sample size estimation methods.Item Open Access Propensity score weighting under limited overlap and model misspecification.(Statistical methods in medical research, 2020-07-21) Zhou, Yunji; Matsouaka, Roland A; Thomas, LainePropensity score weighting methods are often used in non-randomized studies to adjust for confounding and assess treatment effects. The most popular among them, the inverse probability weighting, assigns weights that are proportional to the inverse of the conditional probability of a specific treatment assignment, given observed covariates. A key requirement for inverse probability weighting estimation is the positivity assumption, i.e. the propensity score must be bounded away from 0 and 1. In practice, violations of the positivity assumption often manifest by the presence of limited overlap in the propensity score distributions between treatment groups. When these practical violations occur, a small number of highly influential inverse probability weights may lead to unstable inverse probability weighting estimators, with biased estimates and large variances. To mitigate these issues, a number of alternative methods have been proposed, including inverse probability weighting trimming, overlap weights, matching weights, and entropy weights. Because overlap weights, matching weights, and entropy weights target the population for whom there is equipoise (and with adequate overlap) and their estimands depend on the true propensity score, a common criticism is that these estimators may be more sensitive to misspecifications of the propensity score model. In this paper, we conduct extensive simulation studies to compare the performances of inverse probability weighting and inverse probability weighting trimming against those of overlap weights, matching weights, and entropy weights under limited overlap and misspecified propensity score models. Across the wide range of scenarios we considered, overlap weights, matching weights, and entropy weights consistently outperform inverse probability weighting in terms of bias, root mean squared error, and coverage probability.Item Open Access Racial and Ethnic Differences in Presentation and Outcomes for Patients Hospitalized With COVID-19: Findings From the American Heart Association's COVID-19 Cardiovascular Disease Registry.(Circulation, 2021-06) Rodriguez, Fatima; Solomon, Nicole; de Lemos, James A; Das, Sandeep R; Morrow, David A; Bradley, Steven M; Elkind, Mitchell SV; Williams, Joseph H; Holmes, DaJuanicia; Matsouaka, Roland A; Gupta, Divya; Gluckman, Ty J; Abdalla, Marwah; Albert, Michelle A; Yancy, Clyde W; Wang, Tracy YBackground
The coronavirus disease 2019 (COVID-19) pandemic has exposed longstanding racial and ethnic inequities in health risks and outcomes in the United States. We aimed to identify racial and ethnic differences in presentation and outcomes for patients hospitalized with COVID-19.Methods
The American Heart Association COVID-19 Cardiovascular Disease Registry is a retrospective observational registry capturing consecutive patients hospitalized with COVID-19. We present data on the first 7868 patients by race/ethnicity treated at 88 hospitals across the United States between January 17, 2020, and July 22, 2020. The primary outcome was in-hospital mortality. Secondary outcomes included major adverse cardiovascular events (death, myocardial infarction, stroke, heart failure) and COVID-19 cardiorespiratory ordinal severity score (worst to best: death, cardiac arrest, mechanical ventilation with mechanical circulatory support, mechanical ventilation with vasopressors/inotrope support, mechanical ventilation without hemodynamic support, and hospitalization alone. Multivariable logistic regression analyses were performed to assess the relationship between race/ethnicity and each outcome adjusting for differences in sociodemographic, clinical, and presentation features, and accounting for clustering by hospital.Results
Among 7868 patients hospitalized with COVID-19, 33.0% were Hispanic, 25.5% were non-Hispanic Black, 6.3% were Asian, and 35.2% were non-Hispanic White. Hispanic and Black patients were younger than non-Hispanic White and Asian patients and were more likely to be uninsured. Black patients had the highest prevalence of obesity, hypertension, and diabetes. Black patients also had the highest rates of mechanical ventilation (23.2%) and renal replacement therapy (6.6%) but the lowest rates of remdesivir use (6.1%). Overall mortality was 18.4% with 53% of all deaths occurring in Black and Hispanic patients. The adjusted odds ratios for mortality were 0.93 (95% CI, 0.76-1.14) for Black patients, 0.90 (95% CI, 0.73-1.11) for Hispanic patients, and 1.31 (95% CI, 0.96-1.80) for Asian patients compared with non-Hispanic White patients. The median odds ratio across hospitals was 1.99 (95% CI, 1.74-2.48). Results were similar for major adverse cardiovascular events. Asian patients had the highest COVID-19 cardiorespiratory severity at presentation (adjusted odds ratio, 1.48 [95% CI, 1.16-1.90]).Conclusions
Although in-hospital mortality and major adverse cardiovascular events did not differ by race/ethnicity after adjustment, Black and Hispanic patients bore a greater burden of mortality and morbidity because of their disproportionate representation among COVID-19 hospitalizations.Item Open Access Regression with a right-censored predictor using inverse probability weighting methods.(Statistics in medicine, 2020-08-10) Matsouaka, Roland A; Atem, Folefac DIn a longitudinal study, measures of key variables might be incomplete or partially recorded due to drop-out, loss to follow-up, or early termination of the study occurring before the advent of the event of interest. In this paper, we focus primarily on the implementation of a regression model with a randomly censored predictor. We examine, particularly, the use of inverse probability weighting methods in a generalized linear model (GLM), when the predictor of interest is right-censored, to adjust for censoring. To improve the performance of the complete-case analysis and prevent selection bias, we consider three different weighting schemes: inverse censoring probability weights, Kaplan-Meier weights, and Cox proportional hazards weights. We use Monte Carlo simulation studies to evaluate and compare the empirical properties of different weighting estimation methods. Finally, we apply these methods to the Framingham Heart Study data as an illustrative example to estimate the relationship between age of onset of a clinically diagnosed cardiovascular event and low-density lipoprotein among cigarette smokers.Item Open Access Shock Index Predicts Patient-Related Clinical Outcomes in Stroke.(Journal of the American Heart Association, 2018-09) Myint, Phyo Kyaw; Sheng, Shubin; Xian, Ying; Matsouaka, Roland A; Reeves, Mathew J; Saver, Jeffrey L; Bhatt, Deepak L; Fonarow, Gregg C; Schwamm, Lee H; Smith, Eric EBackground The prognostic value of shock index ( SI ), heart rate divided by systolic blood pressure, in stroke for clinical outcomes other than mortality is not well understood. Methods and Results We examined the Get With The Guidelines-Stroke ( GWTG -Stroke) data to explore the usefulness of SI in predicting in-hospital outcomes in 425 808 acute stroke cases (mean age: 71.0±14.5 years; 48.8% male; 89.7% ischemic stroke and 10.3% intracerebral hemorrhage) admitted between October 2012 and March 2015. Compared with patients with SI of 0.5 to 0.7, patients with SI >0.7 (13.6% of the sample) had worse outcomes, with adjusted odds ratios of 2.00 (95% confidence interval [ CI ], 1.92-2.08) for in-hospital mortality, 1.46 (95% CI , 1.43-1.49) for longer length of hospital stay >4 days, 1.50 (95% CI , 1.47-1.54) for discharge destination other than home, 1.41 (95% CI , 1.38-1.45) for inability to ambulate independently at discharge, and 1.52 (95% CI , 1.47-1.57) for modified Rankin Scale score of 3 to 6 at discharge. Results were similar when analyses were confined to those with available National Institutes of Health Stroke Scale (NIHSS) or within individual stroke subtypes or when SI was additionally included in the models with or without blood pressure components. Every 0.1 increase in SI >0.5 was associated with significantly worse outcomes in linear spline models. The addition of SI to existing GWTG -Stroke mortality prediction models without NIHSS demonstrated modest improvement, but little to no improvement was noted in models with NIHSS . Conclusions SI calculated at the point of care may be a useful prognostic indicator to identify those with high risk of poor outcomes in acute stroke, especially in hospitals with limited experience with NIHSS assessment.