Primary Diagnosis Of Acute Ischemic Stroke Research Articles

Influence of Activated Protein C Resistance on Short-Term Hospital Outcomes Following Admission for Acute Ischemic Stroke in the United States

Introduction: Activated protein C (APC) plays a crucial role in breaking down factor Va and VIIIa, preventing excessive blood clotting. APC resistance occurs when protein C is unable to degrade these factors, leading to a higher risk of thrombosis. This condition can be either hereditary or acquired, with the most common cause being the factor V Leiden mutation. While previous studies have indicated that APC resistance increases the likelihood of acute ischemic stroke (AIS), their specific outcomes have not been extensively studied. Our research aims to bridge this gap via a national study. Methods: We used hospital records via the National Inpatient Sample (NIS) for our study. It consists of de-identified in-patient data, released on an annual basis by HCUP, AHRQ, and collaborating hospitals. Patients admitted with a primary diagnosis of AIS were recruited. We excluded all hospitalizations of ages <18 years. The impact of APCR status on outcomes and in-hospital complications such as acute kidney injury (AKI), myocardial infarction (MI), thrombolysis, mechanical thrombectomy (MT), vasopressor use, seizures, unfavorable discharge (discharge to another center such as short-term hospital, skilled nursing facility, intermediate care facility, and another type of facility) was studied using multivariable regression analysis, while adjusting for the impact of several potential patient and hospital characteristics. Results: Our selection criteria identified 2631890 admissions for AIS between 2016-2020, including 5910 (0.2%) patients also reporting a diagnosis of APCR (Table 1). In addition, APCR patients were younger (mean age 60.1 vs. 70.1 years, p<0.01) with a lower mean Charlson Comorbidity Index (CCI) score (3.50 vs. 3.87, p<0.01), and showed higher odds of a history of prior stroke (19.3% vs. 15.4%, aOR 1.482, 95% CI 1.387-1.584, p<0.01). While both groups were primarily covered by Medicare (65.0% in non-APCR group and 47.3% in APCR patients), a higher proportion of patients with APCR were also covered by private insurance (33.0% vs 19%, p<0.01). The APCR group also showed a higher prevalence of Whites (85.9% vs. 68.2%, p<0.01). Most cases in both cohorts were treated in Urban teaching centers. While higher prevalences of smoking(43.2% vs. 39.8%, p<0.01), obesity (20.3% vs. 14.5%, p<0.01), and drug abuse (4.4% vs. 2.8%, p<0.01) were seen in APCR patients, they also expressed fewer cases of cirrhosis (0.3% vs. 0.7%, p<0.01), diabetes (30.6% vs 39.2%, p<0.01), hypertension (51.9% vs 58.2%, p<0.01), chronic kidney disease (13.7% vs 18.3%, p<0.01), atrial fibrillation (18.8% vs 24.9%, p<0.01), and lipid disorder (53.8% vs 60.3%, p<0.01). After careful adjustments of confounders, APCR patients showed a higher use of mechanical thrombectomy (aOR 1.523, 95% CI 1.374-1.689, p<0.01) and vasopressor use (aOR 1.877, 95% CI 1.435-2.455, p<0.01) and also reported higher odds of seizures (aOR 1.413, 95% CI 1.265-1.578, p<0.01) and unfavorable discharge (aOR 1.065, 95% CI 1.006-1.128, p=0.03). However, lower odds of acute kidney injury (aOR 0.87, 95% CI 0.794-0.952, p<0.01) and death(aOR 0.708, 95% CI 0.597-0.838, p<0.01) were noted. No differences in events of MI (aOR 1.161, 95% CI 0.994-1.358, p=0.06) and thrombolysis (aOR 0.94, 95% CI 0.863-1.024, p=0.159) use were seen between the two groups. Conclusion: The study reported higher short-term outcomes, including increased use of mechanical thrombectomy and vasopressors and higher odds of seizures and unfavorable discharge in APCR patients with acute stroke. However, no similar increased odds of in-patient death, acute kidney injury, thrombolysis, and myocardial infarction were noted. While the impact of APCR on stroke recurrence has been highly debated in prior studies, our analysis provides a novel update showing an increased risk of subsequent stroke in patients with a history of stroke. Encouraging more extensive studies in a clinical setting, with larger groups of people and more extended observation periods, can provide a clearer understanding of the situation and thus improve their long-term outcomes.

In-Hospital Outcomes and Recurrence of Acute Ischemic Stroke in Patients With Solid Organ Malignancy.

The aim of this work was to evaluate the influence of solid organ malignancies on the in-hospital outcomes and recurrent strokes among patients hospitalized with acute ischemic stroke (AIS). Adult hospitalizations with a primary diagnosis of AIS were identified from the Nationwide Readmissions Database from 2016 to 2018. Logistic regression was used to compare the differences in the use of acute stroke interventions and clinical outcomes in patients with and without malignancy. Survival analysis was used to evaluate the risk of readmission due to recurrent stroke after discharge. There were 1,385,840 hospitalizations due to AIS (mean ± SD age 70.4 ± 14.0 years, female 50.2%). Of these, 50,553 (3.7%) had a concurrent diagnosis of solid organ malignancy. The 5 most common malignancies included lung cancer (24.6%), prostate cancer (13.2%), breast cancer (9.3%), pancreatic cancer (6.5%), and colorectal cancer (6.2%). After adjustment for baseline differences, patients with malignancy were more likely to have intraparenchymal hemorrhage (odds ratio [OR] 1.11, 95% CI 1.04-1.19), in-hospital mortality (OR 2.15, 95% CI 2.04-2.28), and discharge disposition other than to home (OR 1.70, 95% CI 1.64-1.75). Patients with malignancy were less likely to receive IV thrombolysis (tissue plasminogen activator [tPA]) and were more likely to undergo mechanical thrombectomy (MT). Among the subgroups of patients treated with tPA or MT, the outcomes were comparable between patients with and without malignancy, except patients with lung cancer remained at a higher risk of mortality and adverse disposition despite these acute stroke interventions. Patients with malignancy were at a higher risk of readmission due to recurrent AIS within 1 year of discharge (hazards ratio 1.18, 95% CI 1.11-1.25), and this risk was driven specifically by the lung and pancreatic cancers. While patients with malignancy generally have worse in-hospital outcomes compared to those without, there is considerable variation in these outcomes according to the different cancer types and the use of acute stroke interventions. The use of tPA and MT is generally safe for eligible patients with an underlying malignancy. Patients with lung and pancreatic cancers have a higher early risk of recurrent stroke and might need more intensive surveillance and careful institution of the optimal secondary prevention measures.

Abstract WP158: Trends In Utilization Of IV Thrombolysis And Mechanical Thrombectomy In Patients With Stroke And Malignancy.

Background and Purpose: Existing data shows that IV thrombolysis (tPA) and mechanical thrombectomy (MT) use in acute ischemic stroke (AIS) patients and malignancy is <2%. Our aim was to determine whether utilization of recanalization therapies has increased in AIS patients with cancer since publication of pivotal MT trials. Methods: All admissions with a primary diagnosis of AIS (weighted n=5,554,161) were identified from the 2007-2018 Nationwide Inpatient Sample. Cancer-associated strokes (CAS) were categorized into hematologic (hem), solid and metastatic (met) cancers. Joint point regression and multivariable-adjusted logistic regression models with interaction terms were used to evaluate rate of change in t-PA and MT use in CAS compared to non-CAS admissions. Results: Across this period, 4.0% of AIS admissions had comorbid CAS. The proportion of AIS hospitalizations with CAS increased from 3.8% in 2007 to 4.4% in 2018. Mean age of CAS was 72.9 (47.6% women) vs. 70.6 years (51.8% women) among non-CAS. CAS patients had fewer vascular risk factors. Highest t-PA usage was in non-CAS pts (7.8%) and lowest use in met-CAS pts (3.8%) and this difference was significant. In contrast MT usage was highest in met-CAS (2.0%) vs non-CAS (1.6%) and hem-CAS (1.2%). A race-by-time interaction revealed an increase in utilization of both therapies in all CAS groups. Pace of the increase was slower in met CAS (OR 0.97, 95%CI 0.95-0.99) per unit increase in year. MT use increased at a faster pace in met-CAS patients (OR 1.07, 95%CI 1.02-1.12) compared to non-CAS. Although overall mortality rates for patients with cancer has decreased for all cancer types, CAS had significantly higher in hospital mortality as compared to NCS (8.9% vs 4.4%, p <0.001). Conclusions: Utilization of both t-PA and MT has increased over the last decade. Contrary to prior studies, the current frequency and pace of increase in MT use is greater in met-CAS admissions compared to non-CAS. Patients with CAS have fewer traditional vascular risk factors and significantly higher in hospital mortality. Future studies should address longer term outcomes in CAS versus non-cancer strokes.

Abstract 134: Population-level Trends In Clinal Outcomes And Endovascular Stroke Therapy In Acute Ischemic Stroke

Intro & Background: Following the publication of the randomized clinical trials in 2015 and 2018 on endovascular stroke therapy (EVT), procedural utilization has increased. The effect of EVT utilization on clinical outcomes in acute ischemic stroke (AIS) at the population-level, however, remains incompletely characterized. Methods & Materials: We performed a retrospective cross-sectional analysis using the Texas Public Use Data File with records from January 2016 through the first quarter of 2020. This dataset includes full sample data on all patients hospital discharged from all state-licensed hospitals. AIS hospitalizations were identified as those with a primary diagnosis of AIS by ICD-10 diagnostic codes. Patients <18 were excluded, as well as patients missing age data. EVT was defined using ICD-10 procedure codes. Excellent clinical outcome was defined as discharge to home. Trends for EVT and percentage of home discharge were assessed by quarter and the correlation between two trends were examined by cross-correlation. Results: Among 165,738 AIS cases, 61% were over 65 years old, 51% were female, 51% were White and 25% were Hispanic. Over the course of the study period, EVT utilization increased 0.25% per quarter [95% CI 0.23-0.27, P<0.001]. Excellent clinical outcomes also increased over this time period, with a 0.21% quarterly increase in patients being discharged home [95% CI 0.16-0.25, p<0.001] (Figure). At the population-level, we observed a positive correlation between increasing EVT utilization and excellent clinical outcomes (R=0.64, p< 0.003). Conclusion: In this state-wide cohort, increasing usage of EVT was positively correlated with excellent clinical outcomes. These data provide evidence for population-level improvements in AIS care with improving EVT access and utilization.

Abstract WMP106: Acute Ischemic Stroke Treatments And Outcomes In Patients With Hematological Malignancies

Background: There is limited evidence to guide treatment decisions in patients with acute ischemic stroke (AIS) who have concurrent hematological malignancies. In this study, we aimed to evaluate the impact of acute stroke interventions and clinical outcomes in this patient population. Methods: Hospitalizations with primary diagnosis of AIS were identified from the Nationwide Readmissions Database 2016-2018. Hospital records with age<18 or with concomitant diagnosis of solid organ malignancy were excluded. Logistic regression was used to compare the differences in acute stroke interventions and clinical outcomes in patients with and without hematological malignancies. Survival analysis was used to evaluate recurrent AIS after discharge. Results: There were 1347150 hospitalizations due to AIS (mean±SD age 70.3±14.1 years, female 50.2%). Of these, 11863 (0.9%) had a concurrent diagnosis of hematological malignancy. Patients with malignancy were older and were less likely to have comorbid cerebrovascular risk factors, except atrial fibrillation. Patients with malignancy were less likely to receive intravenous thrombolysis (tPA) but the rates of endovascular thrombectomy (ET) did not differ between the two groups. After adjustment for baseline differences, patients with malignancy had higher in-hospital mortality [odds ratio (OR): 1.2, 95% confidence interval (CI): 1.0-1.3] but other outcomes like intracranial hemorrhage and discharge disposition were comparable between the two groups. Sub-group analysis according to the type of malignancy (leukemia, lymphoma, plasma cell neoplasms, histiocytic/other) showed that only patients with leukemias had higher mortality and adverse discharge disposition. Among the subgroups of patients treated with tPA or ET, the clinical outcomes were comparable between patients with and without malignancy. Further, the overall risk of readmission due to recurrent ischemic stroke was also similar between patients with and without malignancy (hazards ratio: 1.0, 95% CI: 0.9-1.1). Conclusion: Acute reperfusion in ischemic stroke is safe in patients with hematological malignancies. While patients with malignancy have higher in-hospital mortality, they are not at an increased risk of stroke recurrence.

Abstract WMP88: Endovascular Therapy For Large Vessel Occlusion Stroke With Low NIH Stroke Scale: A Population-Level Assessment

Introduction: There is increasing interest in endovascular therapy (EVT) for patients with large vessel occlusion (LVO) acute ischemic stroke (AIS) presenting with low NIH Stroke Scale. Here, we assess the prevalence of LVO with low NIHSS and real-world trends in utilization of EVT in this population. Methods: We performed a cross-sectional study using the Texas Public Use Data File, which captures all inpatient admissions in the state from non-federal hospitals (10/01/2016-06/30/2020). AIS cases were defined as hospitalizations to acute care hospitals with a primary diagnosis of AIS using ICD-10-CM codes I63.x and NIHSS was determined using ICD-10-CM codes R29.700- R29.742. Low NIHSS was defined as <6 and high NIHSS as ≥ 6. LVO was determined by ICD-10-CM codes and EVT was determined by ICD-10 procedure codes. Comprehensive stroke center (CSC) designation was determined by Texas Department of Health Services published listings. Results: Among 61,524 AIS cases, patients with low NIHSS accounted for 63% and were more likely to be younger, male and white than those with high NIHSS. LVO was twice as prevalent among high NIHSS AIS (52% vs 24% p<0.001) but 44% of LVOs presented with low NIHSS. EVT rates were much lower in low NIHSS LVOs compared to high NIHSS LVOs (4% vs 27%, p<0.001). EVT rates in LVOs increased during the study period (0.4% per quarter, 95% CI 0.3-0.6%, p<0.001), as well in low NIHSS LVOs (0.2% per quarter, 95% CI 0.1-0.3%, p=0.001). These findings, however, were only seen in CSC-certified hospitals, for both high NIHSS LVOs (1.0% per quarter, 95% CI 0.7-1.3%, p<0.001) and low NIHSS LVOs (0.3% per quarter, 95% CI 0.06-0.4%, p=0.010) but not seen in non-CSC hospitals. Conclusions: In this large state-level cohort, nearly one-quarter of low NIHSS patients were found to have LVO, and increasing trends in EVT use were observed in this group. The effectiveness and safety of EVT in low NIHSS LVOs need to be further evaluated in real world clinical settings.

Abstract WMP57: Acute Stroke Interventions And Clinical Outcomes In Patients With Solid Organ Malignancies

Background: There is limited data regarding the safety of acute ischemic stroke (AIS) treatments in patients with solid organ malignancy (SOM). We aimed to evaluate the nationwide use of acute stroke interventions and clinical outcomes in this patient population. Methods: Adult hospitalizations with primary diagnosis of AIS were identified from the Nationwide Readmissions Database 2016-2018. Logistic regression was used to compare the differences in interventions and clinical outcomes in patients with and without SOM. Survival analysis was used to evaluate recurrent AIS after discharge. Results: There were 1385840 hospitalizations due to AIS (mean±SD age 70.4±14.0 years, female 50.2%). Of these, 50553 (3.7%) had a concurrent diagnosis of SOM. Patients with SOM were older, more likely to be male, and had a lower prevalence of comorbid cerebrovascular risk factors, except atrial fibrillation and tobacco use. The five most common malignancies were of lung, prostate, breast, pancreas, and colorectal origins. After adjustment for baseline differences, patients with SOM were more likely to have intraparenchymal hemorrhage (IPH) [odds ratio (OR): 1.1, 95% confidence interval (CI): 1.0-1.2], in-hospital mortality (OR: 2.1, 95% CI: 2.0-2.2), and discharge disposition other than to home (OR: 1.6, 95% CI: 1.6-1.7). The risk of IPH was higher only in pancreatic cancer, in-hospital mortality in all types except prostate cancer, and adverse discharge disposition in all types except prostate and breast cancers. Patients with SOM were less likely to receive intravenous thrombolysis (tPA) but more likely to undergo endovascular thrombectomy (ET). Among the subgroups of patients treated with tPA or ET, outcomes were comparable between patients with and without SOM, except patients with lung cancer remained at a higher risk of mortality and adverse disposition despite these interventions. Patients with SOM had higher risk of readmission due to recurrent AIS within 1 year of discharge (hazards ratio: 1.2, 95% CI: 1.1-1.3), and this risk was entirely driven by lung and pancreatic cancers. Conclusion: Clinical outcomes of AIS in the setting of SOM vary according to the malignancy site. Acute stroke interventions when performed, appear to be safe in most patients with SOM.

Abstract TMP52: Obstructive Sleep Apnea In Acute Ischemic Stroke Patients In The United States: Temporal Trends And Outcomes

Introduction: Obstructive sleep apnea (OSA) is a known ischemic stroke risk factor. We analyzed OSA prevalence trends in hospitalized acute ischemic stroke (AIS) patients and treatment utilization and outcomes among AIS patients with and without OSA. Methods: Hospitalized adults 18 and over with a primary diagnosis of AIS per ICD-9 and 10 codes recorded in the Nationwide Inpatient Sample from 2005-2017 were identified. The diagnosis of OSA was identified by ICD-9 and 10 codes. National estimates were generated using discharge weights. Temporal trends in OSA prevalence were analyzed by logistic regression. Links between OSA and IV-tPA and endovascular thrombectomy (EVT) use, mechanical ventilation, discharge disposition, and in-hospital mortality were assessed by adjusted logistic regression models. Results: Of 5,864,798 AIS patients, 234,339 (4.0%) had OSA (intravenous tPA (n=18,421; 7.9%), EVT (n=3,787; 1.6%), in-hospital deaths (n=10,422; 4.5%)). OSA rates in AIS increased from 0.16% in 2005 to 6.3% in 2017 (p-value < .001). OSA AIS patients were younger (mean age 66 vs. 73 years, p<0.01), male (62.4% vs. 46.8%, p-value; p<0.01), White (73.6% vs. 69.1%, p-value p<0.01), obese (67.1% vs. 32.9%, p-value < 0.01), and had a higher Charlson comorbidity index (mean 3.2 vs. 2.6, p-value < 0.01). Adjusting for demographics and comorbidities, OSA AIS versus non-OSA AIS patients were more likely to be treated with IV- tPA and as likely to receive EVT and mechanical ventilation. Adjusting for demographics, comorbidities, and treatments, OSA AIS patients were less likely to die during hospitalization and more likely to be discharged home. Conclusion: Prevalence of OSA among hospitalized AIS patients increased from 2005-2017. OSA AIS patients were treated at a higher rate with IV-tPA and at a similar rate with EVT. OSA AIS patients had better functional outcomes. Further study is needed to understand the mediators of favorable outcomes in AIS patients diagnosed with OSA.

Acute telestroke evaluations during the COVID-19 pandemic.

We sought to analyze the effect of COVID-19 on telestroke requests and to characterize patients remotely evaluated for acute ischemic stroke (AIS) during this time. This study is a retrospective database review of all telestroke requests at one academic vascular neurology center telestroke network with seven remote sites in the USA between March 15 and April 30, 2020. Data were compared with historical cohort spanning same time frame in 2019 using parametric or nonparametric methods as appropriate. Among telestroke requests, characteristics of age, gender, race/ethnicity, National Institutes of Health Stroke Scale (NIHSS), primary diagnosis of AIS or transient ischemic attack (TIA), and number of patients receiving intravenous alteplase (IV-rtPA) and endovascular therapy (ET) were recorded. There was a 53% decrease in telestroke evaluation requests in 2020 from 2019 (p < 0.00001). Mean NIHSS in 2020 was 9.1 (SD ± 8.4) and mean NIHSS in 2019 was 7.2 (SD ± 7.3) (p = 0.122). Among patients with primary diagnosis of suspected AIS or TIA, mean age was 60.5 years in 2020 (SD ± 17.5) and mean age of 67.0 years in 2019 (SD ± 16.0) (p = 0.038). A significant lower number of telestroke evaluations were performed with a higher mean NIHSS overall and a lower mean age among AIS/TIA-suspected patients. Higher NIHSS and severity in all telestroke evaluations reflect neurological manifestations of AIS and mimics, possibly influenced by COVID-19. The younger age of those with suspected AIS or TIA reflects thrombotic complications in atypical stroke populations.

Abstract MP29: Effects of System-Level Factors on Race/Ethnic Differences in In-Hospital Mortality After Acute Ischemic Stroke

Introduction: Stroke mortality has declined, with differential changes by race; stroke is now the 5 th leading cause of death overall, but 2 nd leading cause of death in blacks. Little is known about recent race/ethnic trends in in-hospital mortality after acute ischemic stroke (AIS) and whether system-level factors contribute to possible differences. Methods: Using the National Inpatient Sample, adults (&gt;18 yrs) with a primary diagnosis of AIS from 2006 to 2017 (n=763,808) were identified. We assessed in-hospital mortality by race/ethnicity (white, black, Hispanic, Asian/Pacific Islander [API], other), sex, and age. Hospitals were categorized by proportion of minority patients served: &lt;25% minority (white hospitals); 25-50% (mixed hospitals), and &gt;50% (minority hospitals). Using survey adjusted logistic regression, the association between race/ethnicity and odds of mortality was assessed, adjusting for key sociodemographic, clinical, and hospital characteristics (e.g. age, comorbidities, stroke severity, DNR status, and palliative care). Results: Overall, mortality decreased from 5.0% in 2006 to 2.9% in 2017, p&lt;0.001. Comparing 2006-2011 to 2012-2017, there was a 66% reduction in mortality after adjustment for covariates, most prominent in whites (68%) and smallest in blacks (58%). Compared to whites, blacks and Hispanics had lower adjusted odds of mortality (AOR 0.82, 95% CI 0.78-0.86 and AOR 0.92, CI 0.86-0.98), primarily driven by those &gt;65 yrs (age x ethnicity interaction p = 0.003). Compared to white men, black, Hispanic, and API men and black women had lower odds of mortality. Adjusted mortality was lower in minorities vs. whites and most pronounced in white hospitals (white: AOR 0.78, 0.73-0.85; mixed: 0.85, 0.80-0.91; minority: 0.89, 0.82-0.95; interaction effect: p=0.018). These differences were present for both minority men and women in white and mixed hospitals, but not women in minority hospitals. Discussion: AIS mortality decreased dramatically in recent years. Overall, black and Hispanic AIS patients have lower mortality than whites, a difference that is most striking in white hospitals. Further study is needed to understand these differences and to what extent biological, sociocultural, and system-level factors play a role.

Abstract MP25: Inequities in Interhospital Transfer for Acute Ischemic Stroke in the United States: Lower Odds for Women and the Underinsured

Background: Patients with acute ischemic stroke (AIS) may undergo interhospital transfer (IHT) for higher level of care. Although the Emergency Medical Treatment and Active Labor Act stipulates that patients should be transferred to and accepted by referral hospitals if indicated, it offers few concrete guidelines, making it vulnerable to bias. We hypothesized that (1) IHT for AIS has increased over recent years and (2) minorities, women, and those without insurance had lower odds of IHT. Methods: Using the National Inpatient Sample, adults (&gt;18 yrs) with a primary diagnosis of AIS from 2010 to 2017 (n=770,970) were identified, corresponding to a weighted sample size of 3,798,440. Those transferred to another acute hospital were labeled IHT. Yearly rates of IHT were assessed. Adjusted odds ratio (AOR) of IHT (vs. not transferred) were compared in 2014-2017 vs. 2010-2013 using a multinomial logistic model, adjusting for socioeconomic, medical, and hospital characteristics. Multinomial logistic regression was used to determine odds of IHT by race/ethnicity, sex, and insurance status, adjusting for the above characteristics. Results: From 2010 to 2017, the proportion of IHT declined from 3.2% (SE 0.2) to 2.9% (SE 0.1). Comparing IHT in 2014-2017 to 2010-2013 showed lower odds of IHT (OR 0.93, 95% CI 0.88-0.99), but this difference did not remain significant in the fully adjusted model. Fully adjusted OR showed that black patients were more likely than white patients to undergo IHT (AOR 1.13, 1.07-1.20). Women were less likely than men to be transferred (AOR 0.89, 0.86-0.92). Compared to those with private insurance, those with Medicaid (AOR 0.86, 0.80-0.91), self-pay (0.64, 0.59-0.70), and no charge (0.64, 0.46-0.88) were less likely to undergo IHT. Conclusions: Adjusted odds of IHT for AIS did not change significantly. Blacks were more likely than whites to be transferred; however, women and the uninsured/underinsured were less likely to be transferred. Further studies are needed to further understand these inequities and develop interventions and policies to ensure that all individuals have equitable access to stroke care, regardless of their race, sex, or ability to pay.

Abstract P76: Effect of Covid-19 Pandemic on Acute Ischemic Stroke Hospitalizations Among Medicare Beneficiaries in the United States

Introduction: Emergency department visits and hospitalizations for acute ischemic stroke (AIS) declined significantly following the declaration of COVID-19 as a national emergency on March 13, 2020 in the United States. No study has examined the volume and nature of AIS hospitalizations among older adults in the U.S. amidst the COVID-19 pandemic. This study examined the trend and compared the characteristics of Medicare fee-for-service (FFS) beneficiaries ≥65 years hospitalized with a primary AIS diagnosis in the same timeframe before and after the COVID-19 pandemic. Methods: We included hospitalizations with a primary diagnosis of AIS (ICD-10 I63) among Medicare FFS beneficiaries from week 11 to 24 in 2019 and 2020. We estimated the percent reduction of AIS hospitalizations between 2019 and 2020 by age, sex, race/ethnicity, and state. We tested for difference in distribution by age group, sex and race/ethnicity between 2019 and 2020 based on χ 2 test. Results: During the 14-weeks from March 8 to June 13, 2020, AIS hospitalizations among FFS beneficiaries were reduced by 23.7% compared to weeks 11 to 24 in 2019 (March 10 to June 15) (49,607 in 2019 vs. 37,860 in 2020). A greater percent reduction in AIS hospitalizations was observed with older age (27.2% among ≥85 years vs. 20.6% among persons 65-74 years, p&lt;0.001). The magnitude of reduction was similar between men (23.8%) and women (23.6%, p=0.791), and among non-Hispanic white (24.2%), non-Hispanic black (22.4%), Hispanic (19.3%), and other (22.4%, p=0.189). AIS hospitalization trends varied by state ranging from 1.6% in New Hampshire to 39.8% in Montana. Conclusion: Hospitalizations with a primary AIS diagnosis among Medicare FFS beneficiaries were reduced by 24% during weeks 11 to 24 of the COVID-19 pandemic compared to the previous year in the United States. AIS hospitalization reductions varied substantially by state. Further study is needed to examine the long-term effects of COVID-19 pandemic on stroke outcomes.

Discharge Against Medical Advice in Acute Ischemic Stroke: the Risk of 30-Day Unplanned Readmission

Discharge against medical advice may be associated with more readmissions. To evaluate DAMA in patients with acute ischemic stroke (AIS) and identify the relationship between DAMA and 30-day unplanned readmissions. A retrospective cohort study. The National Readmission Database was used to identify inpatients with a primary diagnosis of AIS who were either discharged home or DAMA between 2010 and 2017 in the USA. Demographic features, hospital type, comorbidities, stroke risk factors, severity indices, and treatments were compared between patients discharged routinely and DAMA. Multivariable logistic regression was used to evaluate predictors of DAMA, and a double robust inverse probability of treatment weighting method was used to assess the association between DAMA and 30-day unplanned readmissions. Overall, 1,335,484 patients with AIS were included, of whom 2.09% (n = 27,892) were DAMA. The prevalence of DAMA in AIS patients increased from 1.65 in 2010 to 2.57% in 2017. The rates of 30-day unplanned readmissions for DAMA and non-DAMA patients were 16.81% and 7.78%, respectively. Patients with drug abuse, alcohol abuse, smoking, prior stroke, psychoses, and intravenous thrombolysis had greater odds of DAMA. DAMA was associated with all-cause readmissions (OR, 2.04; 95% CI, 2.01-2.07) and remained a strong predictor for transient ischemic attack/stroke-specific and cardiac-specific causes of readmissions. Although the DAMA rate is low in AIS patients, DAMA is a risk factor for all-cause and recurrent stroke-specific readmissions. Future studies are needed to address issues around compliance and engagement with health care to reduce DAMA.

Trends in endovascular interventions for pediatric ischemic stroke at the national level: data from 2000 to 2009.

Present knowledge is limited with regard to endovascular and interventional management of pediatric acute ischemic stroke (AIS). The current practice of neurointerventions in this population was analyzed via a national database. The Kids' Inpatient Database for years 2000, 2003, 2006, and 2009 was examined for patients aged < 18 years discharged with a primary diagnosis of AIS and identified according to ICD-9 codes. Descriptive statistics were tabulated on each of the subcohorts. There were 3467 patients identified; 920 (26.5%) underwent angiograms, 51 (1.5%) angiogram + thrombolysis, and 18 (0.5%) received angiogram + endovascular recanalization. The angiogram only subcohort was significantly younger compared with thrombolysis and endovascular procedure subcohorts (9.8 vs. 12.2 vs. 14.9 years, P < 0.001). Mortality was 4.3%, significantly lower for angiogram only than for thrombolysis (1.1% vs. 18.2%, P < 0.0001). Thrombolysis also had significantly higher hospital charges ($149,045 vs. $64,826, P < 0.0001). While not many differences in outcomes between angiogram only versus endovascular procedures, the latter had higher financial burden ($122,482 vs. $64,826, P < 0.0001). This national study suggests that children receiving neurointerventions tend to be older (> 12 years) and heart and valvular defects are their most likely comorbidities. There was a lower mortality and fewer complications with endovascular procedures when compared with intravenous/intraarterial thrombolysis alone. Thrombolysis was also associated with more non-routine discharges and lengthier stay.

Abstract WP47: Combined Treatment of Rt-PA With Mechanical Thrombectomy is Associated With Better Outcome Than Mechanical Thrombectomy Alone and Possibly Underutilized - A National Inpatient Sample Study

Background and Purpose: 2015 AHA/ASA guidelines recommend mechanical thrombectomy (MT) with rt-PA for eligible patients within 6 hours of acute ischemic stroke (AIS). We evaluated the real world impact of the guidelines by analyzing trends and outcomes of stroke patients discharged from 2012 to 2016 in National Inpatient Sample database. Methods: Patients discharged with primary diagnosis of AIS were identified with ICD-9 codes for 2012 to third quarter of 2015 and ICD-10 codes for 2016 and last quarter of 2015. Patients who received only rt-PA, only MT, rt-PA+MT or no treatment were analyzed for discharge outcomes including length of stay (LOS), inpatient mortality and discharge status to home. Survey procedures were used for analysis. Multivariable regression analysis with pairwise comparison of treatment groups with no treatment group was performed to evaluate outcomes controlling for risk factors and all patient refined DRG severity of illness and risk of mortality scores. Results: A total of 2,290,520 adult AIS patients were in the study with mean age 70.4 years (SE 0.03) and 51.1% (SE 0.08) women. There was a significant increase in treatment with rt-PA (5.86% in 2012 to 7.67% in 2016, OR=1.07, 95% CI 1.05-1.08); and MT (0.55% in 2012 to 1.75% in 2016, OR=1.38, 95%CI 1.31-1.45); but not combination rt-PA+MT (0.54% in 2012 to 0.57% in 2016, OR=1.04, 95% CI 0.99 - 1.08). LOS was significantly reduced for rt-PA (mean 6.07 days in 2012 to 4.91 days in 2016, p&lt;0.0001, 1.7 percent reduction/year), and rt-PA+MT (mean 9.19 days in 2012 to 7.10 days in 2016, p=0.0067, 2.9 percent reduction/year) but not for MT alone (9.61 days in 2012 to 8.51 days in 2016, p=0.50). The odds of patients discharged home was significantly higher by 8%, 9% and 15% among patients who received rt-PA (p&lt;0.0001), MT (p=0.0095) and rt-PA+MT group (p=0.0004), respectively, compared to those who did not receive treatment. There was no significant change in inpatient mortality between the groups. Conclusion: The utilization of MT increased but that of rt-PA+MT remained unchanged from 2012 to 2016. Patients with AIS have better LOS and discharge disposition to home when treated with rt-PA+MT than MT alone. Combined treatment of rt-PA with MT may be underutilized in clinical practice.

Abstract TP70: Utilization and Availability of CT Perfusion in Patients With Acute Ischemic Stroke: A Population Based Study

Introduction: Recent randomized clinical trials have demonstrated benefit for treatment with endovascular stroke therapy (EST) and thrombolysis (IV-tPA) in late presenting acute ischemic stroke (AIS) patients using CT perfusion (CTP). The real-world utilization and availability of this advanced imaging modality is unknown. Methods: We identified all inpatient hospitalizations with a primary diagnosis of AIS using ICD-9/10 codes in Texas Medicare claims (2014-2017) and 5% national Medicare sample (2014-2017) and evaluated imaging utilization given at the Emergency Department (ED) prior to admission. Imaging and treatments were identified using CPT and procedure codes. Primary endpoint was ED-based imaging utilization. EST and CTP-capable hospitals were defined as those performing at least one EST or CTP within that calendar year. Results: In the Texas cohort, among 50,797 admissions for AIS, 54% were female, median age was 77 [IQR 69-84], and 78% were white. 2% received EST and 9% received IV-tPA. 76% of AIS patients and 80% of those with EST received ED-based neuro-imaging at the treating hospital (Fig. 1). 58% of all AIS patients were evaluated in EST-capable hospitals. 75% of all AIS patients, 54 % of those with EST, and 70% of those with IV-tPA were evaluated at non-CTP-capable hospitals. 9% of IV-tPA and 17% of EST-treated patients underwent CTP; rates of MRI were greater (Fig. 1). These findings were maintained in the nationwide sample. Among 37,507 admissions for AIS, CTA was performed in 17%, MRI in 30%, and CTP in 3%. Among the 3% of AIS patients treated with EST, CTA was performed in 65%, MRI in 66%, and CTP in 14%. Conclusion: In this population-based cohort, three out of four AIS admissions and half of EST procedures were at non-CTP performing hospitals. The limited availability and utilization of CTP suggest that an alternative imaging paradigm (e.g. MRI) may be beneficial in delayed time-window EST and thrombolysis.

Benefits of bariatric surgery in patients with acute ischemic stroke-a national population-based study.

To explore the effects of prior bariatric surgery (prior BS) on clinical outcomes in hospitalized patients with acute ischemic stroke (AIS). Inpatient hospital admissions from the Nationwide Inpatient Sample. We identified hospitalized patients with a primary diagnosis of AIS between 2006 and 2014. The primary endpoint was in-hospital mortality. Secondary endpoints included disability status, poststroke complications, and healthcare utilization indicators, including length of hospital stay and total cost. Multivariate regression analyses were performed after adjusting for potential confounders to compare outcomes between patients with prior BS and those with morbid obesity. Of 24,534 (weighted 121,578) patients with AIS, 1654 (weighted 8154) reported a history of BS, and the rest were diagnosed with morbid obesity. Rates of prior BS and morbid obesity in AIS have significantly increased over the study period. Patients with prior BS were younger and more likely to be white, female, with fewer co-morbidities and poststroke complications, and higher rates of thrombolysis treatment. Multivariate regression analyses revealed that prior BS with body mass index <35 kg/m2 was associated with lower mortality (odds ratio [OR] .58, 95% confidence interval [CI] .37-.90), lower odds of moderate-to-severe disability (OR .64, 95% CI .56-.73), acute respiratory failure (OR .63, 95%CI .45-.87), sepsis (OR .50, 95% CI .26-.96), acute kidney failure (OR.67,95% CI .52-.87), 13% shorter hospitalization, and 6% lower total hospital costs. Among hospitalized patients with AIS, prior BS with body mass index <35 kg/m2 is associated with lower in-hospital mortality, fewer poststroke complications, improved disability status, and better healthcare utilization.

Abstract WP433: Effect of Race on Rates of Patent Foramen Ovale Closure during Acute ischemic Stroke Hospitalization in the United States

Background: Published data indicate that African American stroke patients are significantly less likely than their non-Hispanic White counterparts to receive therapeutic procedures in acute ischemic stroke (AIS). Little is known about frequency of PFO closure for secondary stroke prevention by race among patients with cryptogenic stroke. Objective: To investigate trends in PFO closure among hospitalized patients in the U.S., with an emphasis on treatment by race. Methods: The Nationwide Inpatient Sample was queried from 2006 to 2014 for all patients older than 18-years of age with a primary diagnosis of AIS who had procedure codes for PFO closure excluding congenital heart disease. We utilized multivariable logistic regression analyses to study the independent association between race and trends in PFO closure. Results: A population of patients with AIS (n=1028565), excluding congenital heart disease, was analyzed. The queried was divided by PFO closure (n=384) and no PFO closure (n=1028181). Demographic variables included age, gender (male or female) race (White, African American, Hispanic, others) and payer status (Medicare, Medicaid, private, other). In multivariable logistic regression, the odds to have a PFO closure was greatest in the 18-45 age group [age 45-65 (Odds Ratio [OR]: 0.27, 95% CI: 0.20-0.35); age 65-84 (OR: 0.11, 95% CI: 0.81-0.15); age ≥85 (OR: 0.02, 95% CI: 0.01-0.05)], no difference among genders was found (OR: 1.14, 95% CI: 0.93-1.40). African Americans were less likely have PFO closure (OR: 0.51, 95%, CI: 0.35-0.74) when compared to Whites. Private insurance (OR: 1.5, 95% CI: 1.16-2.16); urban teaching hospitals (OR: 3.0, 95% CI: 1.35-6.83); higher median household income for patient’s ZIP code (OR: 2.14, 95% CI: 1.46-3.11); higher Charlson’s Comorbidity Index (OR: 0.78, 95% CI: 0.68-0.90) and admission in 2011-2014 (OR: 0.49, 95% CI: 0.31-0.78) were found to increase the likelihood of having a percutaneous PFO closure after an AIS. Conclusions: Over the last decade in the U.S., being African American was associated with a significantly lower likelihood of receiving percutaneous PFO closure. Now that the beneficial role of PFO closure for cryptogenic stroke is established, this racial disparity needs to be monitored and bridged.

Abstract WP250: Trends in Outcomes Associated With Thrombectomy Treatment Among Acute Ischemic Stroke Patients: Retrospective Analysis of 2011-2017 Premier Hospital Database

Objectives: Mechanical thrombectomy has become the cornerstone of acute ischemic stroke (AIS) treatment. This study evaluated trends in discharge status, length of stay (LoS), operating room (OR) time, readmissions and costs among AIS patients who underwent mechanical thrombectomy treatment. Methods: This retrospective cohort study used 2011-2017Q3 Premier Healthcare Database to evaluate discharge status, length of stay (LoS), operating room (OR) time, readmissions, index inpatient costs for AIS patients aged ≥18 years who underwent mechanical thrombectomy. Patients with a diagnosis of AIS in 12-month baseline or with LoS ≤ 1 day were excluded. The Mann-Kendall statistic was used to examine trends in economic and clinical outcomes associated with thrombectomy between 2011 and 2017. Results: Among 505,824 patients identified with a primary diagnosis of AIS between 2011 and 2017, 11,811 (2.34%) patients were treated with mechanical thrombectomy. The percentage of AIS patients who underwent thrombectomy significantly increased from 1.33% in 2011 to 4.44% in 2017 (p&lt;0.01). The mean age of patients was 66.47 ± 14.75 years, with 51.97% being male. Among AIS patients who underwent thrombectomy, the discharge to home significantly increased from 17.69% in 2011 to 29.64% in 2017 (p&lt; 0.01), while discharge to long-term facility decreased from 53.47% to 49.69% (p=0.10). Mortality rate significantly decreased from 21.60% to 12.64% during the same time period (p&lt; 0.01). The mean OR time declined from 200.73 minutes (2011) to 170.11 minutes (2017) while LoS significantly decreased by 2.95 days (p&lt; 0.01). All-cause 365-day readmission rate decreased from 24.15% in 2011 to 19.78% in 2017 (P=0.35). The index inpatient hospital cost of AIS patients who received thrombectomy significantly declined from $50,516.54 to $42,026.90 (p&lt; 0.01). Conclusions: The economic and clinical outcomes among AIS patients receiving mechanical thrombectomy treatment improved during the study period. However, the overall burden of stroke among patients who received thrombectomy remains high.

Abstract WP434: Effect of Race on Rates of Hemicraniectomy During Acute Ischemic Stroke Hospitalization in the United States

Background: surgical decompressive techniques have shown a significant reduction in mortality in acute ischemic stroke (AIS) compared to medical treatment. Limitations in acute stroke therapies have been described among Hispanic and African American populations compared to other races. Objective: To investigate trends in hemicraniectomy among hospitalized patients in the United States, with emphasis on treatment by race. Methods: The Nationwide Inpatient Sample was queried from 2006 to 2015 for all patients older than 18-years of age with a primary diagnosis of AIS who had procedure codes for craniotomy excluding posterior fossa territory infarctions. Frequency of hemicraniectomy in patients with AIS hospitalization was determined. We utilized multivariable logistic regression analyses to study the independent association between race and trends in hemicraniectomy. Results: A population of patients with AIS (n=715649) was analyzed. The queried was divided by hemicraniectomy (n=1514) and no hemicraniectomy (n=714135). Demographic variables included age, gender (male or female), race (White, African American, Hispanic, others) and payer status (Medicare, Medicaid, private, other). In multivariable analysis, adjusted for potential confounders the odds to have a hemicraniectomy was greatest in the 18-44 age group [age 45-64 (Odds Ratio [OR]: 0.49, 95% CI: 0.42-0.58); age 65-84 (OR: 0.16, 95% CI: 0.13-0.20); age ≥85 (OR: 0.007, 95% CI: 0.003-0.01)]. Medicare insurance [Medicaid (OR: 1.5, 95% CI: 1.2-1.9); Private insurance (OR: 1.7, 95% CI: 1.43-2.03)]; urban teaching hospital (OR: 1.57, 95% CI: 3.63-12.05); prior administration of intravenous tPA (OR: 2.64, 95% CI: 2.21-3.16); being admitted after 2009 (2009-2011 OR: 1.68, 95% CI: 1.13-2.13; 2012-2014 OR: 1.81, 95% CI: 1.44-2.27) and coma status (OR: 15.8, 95% CI: 13.1-19.2) were found to increase the likelihood of having a hemicraniectomy after an AIS. The Hispanic population was more likely to have a hemicraniectomy when compared to White (OR: 1.28, 95% CI: 1.02-1.60). Conclusions: Over the last decade in the United States, being Hispanic was independently associated with an increased likelihood to have a hemicraniectomy.