Analysis of Prescriptions for Dual Antiplatelet Therapy After Acute Ischemic Stroke

Outcomes Following Minimally Invasive Surgery for Intracerebral Hemorrhage in the AHA Get With The Guidelines Registry

BACKGROUND

The efficacy of minimally invasive surgery (MIS) in improving outcomes after nontraumatic intracerebral hemorrhage (ICH) remains uncertain, with inconsistent findings from randomized clinical trials. Our objective was to evaluate the real-world impact of MIS on ICH outcomes using a nationally representative cohort.

METHODS

We performed a retrospective cohort study of patients with a nontraumatic ICH enrolled in the American Heart Association Get With The Guidelines-Stroke Registry between January 1, 2011, and December 31, 2021. We excluded patients with a diagnosis of ischemic stroke or other intracranial hemorrhage subtypes, those who underwent open craniotomy or craniectomy, and patients transferred to another hospital. The exposure was MIS, defined as a composite of stereotactic surgical evacuation and endoscopic surgical evacuation. The primary outcome was in-hospital mortality, while secondary outcomes included functional outcomes at discharge (discharge disposition, ambulatory status, and modified Rankin Scale score). We matched patients who underwent MIS with nonsurgical patients using overlap propensity matching and used multiple logistic regression to study the association between MIS and outcomes.

RESULTS

Among 684 467 patients with ICH, 555 964 were included; the mean age was 68 (SD, 15.3) years, and 262 999 (47.3%) were female. MIS was performed in 703 patients of whom 312 had stereotactic surgery and 391 had endoscopic surgery. In the matched cohort, in-hospital deaths occurred in 60 of 446 (13.5%) with MIS and 8321 of 35 361 patients (23.5%) without surgery. In regression analyses, MIS was associated with lower in-hospital mortality (adjusted odds ratio, 0.50 [95% CI, 0.39-0.65]) and favorable discharge disposition (adjusted odds ratio, 1.93 [95% CI, 1.61-2.32]) but not with ambulatory status or functional outcomes. In additional analyses, stereotactic surgery and endoscopic surgery were independently associated with lower mortality.

CONCLUSIONS

In a large diverse cohort of patients with ICH, MIS was associated with lower in-hospital mortality and favorable discharge disposition. These findings support efforts to understand the durable impact of MIS in patients with ICH.

Evidence-informed language: interpretation and impact on intentions to treat - results of an online survey of medical students and specialists in German-speaking countries

OBJECTIVES

Currently, there is no generally accepted consensus on how to translate strength of evidence into language. Against this background, we here investigated how widely used verbal descriptors of evidence grades and clinical practice recommendations, respectively, are understood, interpreted and transferred into intentions to treat. We explored differences between medical specialists and undergraduate medical students.

DESIGN

Cross-sectional, anonymous online survey. Assessment was based on publicly available proposals for wording to characterise strength of evidence from randomised versus non-randomised trials and of clinical practice recommendations, respectively.

SETTING

The online survey was conducted between September 2021 and March 2022 and promoted by several professional organisations in German-speaking European countries (Germany, Austria and Switzerland).

PARTICIPANTS

Medical students, trainees and medical specialist (open to all medical specialties).

OUTCOME

The survey was composed of two sections: (1) Aim of the first survey section was to assess if the linguistic differentiation between results from randomised versus non-randomised studies is correctly understood as put forward by the proponents. To this end, participants were asked to grade the relative weight of the expression for the results of a randomised trial versus two proposals for how to express the results of non-randomised studies. (2) Next, strong positive, weak positive, weak negative and strong negative clinical recommendations were presented, and participants were asked to answer in a forced-choice format if they would treat all/no patients, selected patients or only consider treatment. Additionally, the number of eligible patients who would be treated was assessed.

RESULTS

N=1081 physicians and N=539 medical students completed the survey. (1) Less than half of the participants (48.5%) interpreted use of 'associated with' as linguistic differentiation between results from randomised versus non-randomised trials in a sense as put forward by the proponents. However, use of the subjunctive mood ('could') resulted in 87.3% correct differentiations. (2) Even with only four types of clinical practice recommendations (positive/negative and strong/weak), interpretation and translation into intention to treat, respectively, showed a heterogeneous picture: while the presentation of a strong clinical recommendation led to largely congruent responses, the interpretation of weak recommendations showed a high variability, with no clear response pattern for intentions to treat. Responses from physicians and medical students were largely comparable.

CONCLUSION

This study demonstrates limitations in the currently used linguistic expressions of strength of evidence and clinical practice recommendations and supports the need to prospectively test effects of language on intentions to treat prior to implementation of a certain wording. Study results cast doubt on that linguistic means alone will lead to optimally targeted intentions to treat.

Proton Pump Inhibitors Use in Patients With Ischemic Stroke on Dual Antiplatelet Therapy at Low Risk of Upper Gastrointestinal Bleeding

BACKGROUND

Current guidelines lack recommendations regarding the use of proton pump inhibitors (PPIs) for preventing upper gastrointestinal bleeding (UGIB) among patients at low risk for UGIB treated with dual antiplatelet therapy for ischemic stroke (IS). Our objective was to assess the effectiveness of PPIs in lowering the risk of significant UGIB in this patient group.

METHODS AND RESULTS

A retrospective cohort study was conducted involving patients at low risk for UGIB admitted for IS between 2014 and 2018 and treated with dual antiplatelet therapy. The study used a nationwide claims database in Korea. The primary end point was significant UGIB during 12 months after IS. To evaluate the risk of significant UGIB based on PPI use, we performed a multivariable Cox regression analysis. Subgroup analyses and propensity score matching analysis were conducted for validation. Among 96 722 patients with IS at low risk for UGIB who were on dual antiplatelet therapy (mean age, 67.0 years; men: 63.0%), 16 084 (16.6%) were treated with PPIs. During 12 months of follow-up, 325 patients experienced significant UGIB, and 479 experienced any UGIB. PPI use was associated with a reduced risk of significant UGIB (hazard ratio, 0.63 [95% CI, 0.45-0.89]; P=0.009). This association was consistent in the subgroup and propensity score matching analyses.

CONCLUSIONS

In patients with IS receiving dual antiplatelet therapy, PPI use reduced the risk of significant UGIB by 37% on average, even among low-risk patients. However, the use of PPIs in this patient group was limited, highlighting the need for additional prospective studies.

Beyond RCTs: Short-term dual antiplatelet therapy in secondary prevention of ischemic stroke and transient ischemic attack

BACKGROUND AND PURPOSE

Randomized controlled trials (RCTs) proved the efficacy of short-term dual antiplatelet therapy (DAPT) in secondary prevention of minor ischemic stroke or high-risk transient ischemic attack (TIA). We aimed at evaluating effectiveness and safety of short-term DAPT in real-world, where treatment use is broader than in RCTs.

METHODS

READAPT (REAl-life study on short-term Dual Antiplatelet treatment in Patients with ischemic stroke or Transient ischemic attack) (NCT05476081) was an observational multicenter real-world study with a 90-day follow-up. We included patients aged 18+ receiving short-term DAPT soon after ischemic stroke or TIA. No stringent NIHSS and ABCD2 score cut-offs were applied but adherence to guidelines was recommended. Primary effectiveness outcome was stroke (ischemic or hemorrhagic) or death due to vascular causes, primary safety outcome was moderate-to-severe bleeding. Secondary outcomes were the type of ischemic and hemorrhagic events, disability, cause of death, and compliance to treatment.

RESULTS

We included 1920 patients; 69.9% started DAPT after an ischemic stroke; only 8.9% strictly followed entry criteria or procedures of RCTs. Primary effectiveness outcome occurred in 3.9% and primary safety outcome in 0.6% of cases. In total, 3.3% cerebrovascular ischemic recurrences occurred, 0.2% intracerebral hemorrhages, and 2.7% bleedings; 0.2% of patients died due to vascular causes. Patients with NIHSS score ⩽5 and those without acute lesions at neuroimaging had significantly higher primary effectiveness outcomes than their counterparts. Additionally, DAPT start >24 h after symptom onset was associated with a lower likelihood of bleeding.

CONCLUSIONS

In real-world, most of the patients who receive DAPT after an ischemic stroke or a TIA do not follow RCTs entry criteria and procedures. Nevertheless, short-term DAPT remains effective and safe in this population. No safety concerns are raised in patients with low-risk TIA, more severe stroke, and delayed treatment start.

Uptake of Dual Antiplatelet Therapy After High-Risk Transient Ischemic Attack at a University Hospital

Multiple randomized controlled trials have demonstrated that dual antiplatelet therapy (DAPT) significantly reduces the risk of subsequent stroke as compared to aspirin monotherapy after high-risk transient ischemic attack (TIA) or minor ischemic stroke. We sought to evaluate the uptake of DAPT after high-risk TIA at a single center. We conducted a retrospective cohort study of consecutive TIA patients admitted via the Emergency Department (ED) of Bern University Hospital (1/1/2018-12/31/2019). We use descriptive statistics to detail cohort characteristics and compared patients treated with DAPT to those not treated. Statistical significance was set at α = 0.05 and all tests of comparison were two-sided. A total of 383 TIA patients were seen during the study period, 247 were eligible for DAPT. Among those eligible for DAPT, mean age was 72 years and 51% were female. A total of 49 (19.8%) eligible TIA patients were treated with DAPT; use of DAPT significantly increased from 2018 to 2019. Patients admitted to the stroke unit or intensive care unit (n = 33) had a significantly higher proportion of DAPT treatment as compared to those admitted to the general neurology ward or discharged to home from the ED. DAPT use was also significantly higher in patients with large artery atherosclerotic disease (n = 23) as compared to other etiological subtypes and significantly higher among patients who arrived to the ED within 24 h of symptom onset (n = 178). In conclusion, we found that only 2 out of every 10 high-risk TIA patients received DAPT in the years following its introduction in the clinical practice. Our results suggest that strategies to improve the uptake of new, evidence-based secondary stroke prevention treatment after high-risk TIA are needed.

Contemporary Statistics of Acute Ischemic Stroke and Transient Ischemic Attack in 2021: Insights From the CRCS-K-NIH Registry

This report presents the latest statistics on the stroke population in South Korea, sourced from the Clinical Research Collaborations for Stroke in Korea-National Institute for Health (CRCS-K-NIH), a comprehensive, nationwide, multicenter stroke registry. The Korean cohort, unlike western populations, shows a male-to-female ratio of 1.5, attributed to lower risk factors in Korean women. The average ages for men and women are 67 and 73 years, respectively. Hypertension is the most common risk factor (67%), consistent with global trends, but there is a higher prevalence of diabetes (35%) and smoking (21%). The prevalence of atrial fibrillation (19%) is lower than in western populations, suggesting effective prevention strategies in the general population. A high incidence of large artery atherosclerosis (38%) is observed, likely due to prevalent intracranial arterial disease in East Asians and advanced imaging techniques. There has been a decrease in intravenous thrombolysis rates, from 12% in 2017-2019 to 10% in 2021, with no improvements in door-to-needle and door-to-puncture times, worsened by the coronavirus disease 2019 pandemic. While the use of aspirin plus clopidogrel for non-cardioembolic stroke and direct oral anticoagulants for atrial fibrillation is well-established, the application of direct oral anticoagulants for non-atrial fibrillation cardioembolic strokes in the acute phase requires further research. The incidence of early neurological deterioration (13%) and the cumulative incidence of recurrent stroke at 3 months (3%) align with global figures. Favorable outcomes at 3 months (63%) are comparable internationally, yet the lack of improvement in dependency at 3 months highlights the need for advancements in acute stroke care.

Stroke and high-risk TIA outcomes with reduction of treatment duration when treatment initiated in emergency rooms (SHORTER-study)

BACKGROUND

Following transient ischemic attack (TIA) and minor stroke, the risk of recurrent stroke can be significantly reduced with short-duration dual antiplatelet therapy (DAPT). We wish to investigate whether 10 days of DAPT is as effective as 21 days' treatment.

STUDY DESIGN

This is an open-label, randomized, parallel-group study comparing whether 10 days of DAPT treatment (ASA + clopidogrel) is non-inferior to 21 days of DAPT in patients with acute ischemic stroke (AIS) or high-risk TIA. In both groups, DAPT is started within 24 hours of symptom onset. This study is being conducted in approximately 15 study sites in the Kingdom of Saudi Arabia. The planned sample size is 1932.

OUTCOMES

Non-inferiority of 10 days compared to 21 days of DAPT in the prevention of the composite endpoint of stroke and death at 90 days in AIS/TIA patients. The primary safety outcome is major intra-cranial and systemic hemorrhage.

STUDY PERIOD

Enrolment started in the second quarter of 2023, and the completion of the study is expected in the fourth quarter of 2025.

DISCUSSION

The trial is expected to show that 10 days of DAPT is non-inferior for the prevention of early recurrence of vascular events in patients with high-risk TIAs and minor strokes.

Trends in Dual Antiplatelet Therapy of Aspirin and Clopidogrel and Outcomes in Ischemic Stroke Patients Noneligible for POINT/CHANCE Trial Treatment

BACKGROUND

Recent clinical trials established the benefit of dual antiplatelet therapy with aspirin and clopidogrel (DAPT-AC) in early-presenting patients with minor ischemic stroke. However, the impact of these trials over time on the use and outcomes of DAPT-AC among the patients with nonminor or late-presenting stroke who do not meet the eligibility criteria of these trials has not been delineated.

METHODS AND RESULTS

In a multicenter stroke registry, this study examined yearly changes from April 2008 to August 2022 in DAPT-AC use for stroke patients ineligible for CHANCE/POINT (Clopidogrel in High-Risk Patients with Acute Nondisabling Cerebrovascular Events/Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke) clinical trials due to National Institutes of Health Stroke Scale >4 or late arrival beyond 24 hours of onset. A total of 32 118 patients (age, 68.1±13.1 years; male, 58.5%) with National Institutes of Health Stroke Scale of 4 (interquartile range, 1-7) were analyzed. In 2008, DAPT-AC was used in 33.0%, other antiplatelets in 62.7%, and no antiplatelet in 4.3%. The frequency of DAPT-AC was relatively unchanged through 2013, when the CHANCE trial was published, and then increased steadily, reaching 78% in 2022, while other antiplatelets decreased to 17.8% in 2022 (Ptrend<0.001). From 2011 to 2022, clinical outcomes nonsignificantly improved, with an average relative risk reduction of 2%/y for the composite of stroke, myocardial infarction, and all-cause mortality, both among patients treated with DAPT-AC and patients treated with other antiplatelets.

CONCLUSIONS

Use of DAPT-AC in stroke patients with stroke ineligible for recent DAPT clinical trials increased markedly and steadily after CHANCE publication in 2013, reaching deployment in nearly 4 of every 5 patients by 2022. The secondary prevention in patients with ischemic stroke seems to be gradually improving, possibly due to the enhancement of risk factor control.

StrokeClassifier: ischemic stroke etiology classification by ensemble consensus modeling using electronic health records

Determining acute ischemic stroke (AIS) etiology is fundamental to secondary stroke prevention efforts but can be diagnostically challenging. We trained and validated an automated classification tool, StrokeClassifier, using electronic health record (EHR) text from 2039 non-cryptogenic AIS patients at 2 academic hospitals to predict the 4-level outcome of stroke etiology adjudicated by agreement of at least 2 board-certified vascular neurologists' review of the EHR. StrokeClassifier is an ensemble consensus meta-model of 9 machine learning classifiers applied to features extracted from discharge summary texts by natural language processing. StrokeClassifier was externally validated in 406 discharge summaries from the MIMIC-III dataset reviewed by a vascular neurologist to ascertain stroke etiology. Compared with vascular neurologists' diagnoses, StrokeClassifier achieved the mean cross-validated accuracy of 0.74 and weighted F1 of 0.74 for multi-class classification. In MIMIC-III, its accuracy and weighted F1 were 0.70 and 0.71, respectively. In binary classification, the two metrics ranged from 0.77 to 0.96. The top 5 features contributing to stroke etiology prediction were atrial fibrillation, age, middle cerebral artery occlusion, internal carotid artery occlusion, and frontal stroke location. We designed a certainty heuristic to grade the confidence of StrokeClassifier's diagnosis as non-cryptogenic by the degree of consensus among the 9 classifiers and applied it to 788 cryptogenic patients, reducing cryptogenic diagnoses from 25.2% to 7.2%. StrokeClassifier is a validated artificial intelligence tool that rivals the performance of vascular neurologists in classifying ischemic stroke etiology. With further training, StrokeClassifier may have downstream applications including its use as a clinical decision support system.

Length of Hospitalization and Mortality among Stroke Patients before and after the Implementation of a Specialized Unit: A Retrospective Cohort Study Using Real-World Data from One Reference Hospital in Southern Brazil

Stroke constitutes a significant global cause of mortality and disability. The implementation of stroke units influences hospital quality indicators, guiding care management. We aimed to compare hospital length of stay (LOS), in-hospital mortality, and post-discharge mortality between stroke patients admitted in the pre- and post-implementation periods of a stroke unit in a public hospital in southern Brazil. This retrospective cohort study used real-world data from one reference hospital, focusing on the intervention (stroke unit) and comparing it to the general ward (control). We analyzed the electronic medical records of 674 patients admitted from 2009 to 2012 in the general ward and 766 patients from 2013 to 2018 in the stroke unit. Admission to the stroke unit was associated with a 43% reduction in the likelihood of prolonged hospitalization. However, there was no significant difference in the risk of in-hospital mortality between the groups (Hazard ratio = 0.90; Interquartile range = 0.58 to 1.39). The incidence of death at three, six and twelve months post-discharge did not differ between the groups. Our study results indicate significant improvements in care processes for SU patients, including shorter LOS and better adherence to treatment protocols. However, our observations revealed no significant difference in mortality rates, either during hospitalization or after discharge, between the SU and GW groups. While SU implementation enhances efficiency in stroke care, further research is needed to explore long-term outcomes and optimize management strategies.

Cost-Effectiveness of Increased Use of Dual Antiplatelet Therapy After High-Risk Transient Ischemic Attack or Minor Stroke

BACKGROUND

Rates of dual antiplatelet therapy (DAPT) after high-risk transient ischemic attack or minor ischemic stroke (TIAMIS) are suboptimal. We performed a cost-effectiveness analysis to characterize the parameters of a quality improvement (QI) intervention designed to increase DAPT use after TIAMIS.

METHODS AND RESULTS

We constructed a decision tree model that compared current national rates of DAPT use after TIAMIS with rates after implementing a theoretical QI intervention designed to increase appropriate DAPT use. The base case assumed that a QI intervention increased the rate of DAPT use to 65% from 45%. Costs (payer and societal) and outcomes (stroke, myocardial infarction, major bleed, or death) were modeled using a lifetime horizon. An incremental cost-effectiveness ratio <$100 000 per quality-adjusted life year was considered cost-effective. Deterministic and probabilistic sensitivity analyses were performed. From the payer perspective, a QI intervention was associated with $9657 in lifetime cost savings and 0.18 more quality-adjusted life years compared with current national treatment rates. A QI intervention was cost-effective in 73% of probabilistic sensitivity analysis iterations. Results were similar from the societal perspective. The maximum acceptable, initial, 1-time payer cost of a QI intervention was $28 032 per patient. A QI intervention that increased DAPT use to at least 51% was cost-effective in the base case.

CONCLUSIONS

Increasing DAPT use after TIAMIS with a QI intervention is cost-effective over a wide range of costs and proportion of patients with TIAMIS treated with DAPT after implementation of a QI intervention. Our results support the development of future interventions focused on increasing DAPT use after TIAMIS.

Dual Antiplatelet Therapy for the Acute Management and Long-term Secondary Prevention of Ischemic Stroke and Transient Ischemic Attack, An Updated Review

To improve the efficacy over antiplatelet monotherapy, dual antiplatelet therapy (DAPT) has been increasingly adopted in the management of non-cardioembolic stroke. For minor ischemic stroke and high-risk transient ischemic attack, the aspirin-clopidogrel combination is now recommended for acute short-term treatment, whereas aspirin-ticagrelor combination may be considered in selected patients, especially those with resistance to clopidogrel. For long-term stroke prevention, aspirin-dipyridamole combination has been used as an alternative to antiplatelet monotherapy, and aspirin or clopidogrel combined with cilostazole may be prescribed for added protection in high-risk patients. In this paper, we review the development of DAPT from a historical perspective and describe the findings from major clinical trials published up until the end of 2023. Using the 2021 American Heart Association guideline for secondary stroke prevention as a basis for our recommendations, we further discuss areas of controversy and more recent developments to provide an updated review for clinicians to consider in their daily practice.

Antithrombotic and Statin Prescription After Intracerebral Hemorrhage in the Get With The Guidelines-Stroke Registry

BACKGROUND

Survivors of intracerebral hemorrhage (ICH) face an increased risk of ischemic cardiovascular events. Current ICH guidelines do not provide definitive recommendations regarding the use of antithrombotic and statin therapies. We, therefore, sought to study practice patterns and factors associated with the use of such medications after ICH.

METHODS

This was a cross-sectional study of patients with ICH in the Get With The Guidelines-Stroke registry, between 2011 and 2021. Patients transferred to another hospital, those who died during hospitalization, and those with missing information on discharge medications were excluded. The study exposure was the proportion of patients who were prescribed antithrombotic or statin medications. We first ascertained the proportion of patients prescribed antithrombotic and lipid-lowering medications at discharge overall and across strata defined by pre-ICH use and history of previous ischemic vascular disease or atrial fibrillation. We then studied factors associated with the discharge prescription of these medications after ICH, using multiple logistic regressions.

RESULTS

In the final cohort, 50 416 (10.4%) of 486 586 patients with ICH were prescribed antiplatelet medications, 173 322 (35.1%) of 493 491 patients with ICH were prescribed statins, and 27 085 (5.4%) of 486 585 patients with ICH were prescribed anticoagulation therapy at discharge. The proportion of patients with antiplatelet therapy was 16.6% with pre-ICH use and 15.6% in those with previous ischemic vascular disease. Statins were prescribed to 41.1% and 43.7% of patients on previous lipid-lowering therapy and ischemic vascular disease, respectively. Anticoagulation therapy was restarted in 11.1% of patients. In logistic regression analysis, factors associated with higher use of antithrombotic or statin therapies after ICH were younger age, male sex, pre-ICH medication use, previous ischemic vascular disease, atrial fibrillation, lower admission National Institutes of Health Stroke Scale, longer length of stay, and favorable discharge outcome.

CONCLUSIONS

Few patients with ICH are prescribed antithrombotic or statin therapies at hospital discharge. Given the emerging association between ICH and future major cardiovascular events, trials examining the net benefit of antiplatelet and lipid-lowering therapy after ICH are warranted.

Appropriate use of antiplatelet medications following transient ischemic attacks and stroke: a 9-year study from the Middle East

Background and purpose

Guidelines recommend that patients with high-risk TIAs and minor strokes presenting within 1-3 days from onset should be offered dual antiplatelet therapy (DAPT). There are little data on real-world adherence to these recommendations. We evaluated the appropriateness of DAPT use in TIA and stroke patients in a prospective database.

Methods

The Qatar Stroke Database began the enrollment of patients with TIAs and acute stroke in 2014 and currently has ~16,000 patients. For this study, we evaluated the rates of guideline-adherent use of antiplatelet treatment at the time of discharge in patients with TIAs and stroke. TIAs were considered high-risk with an ABCD2 score of 4, and a minor stroke was defined as an NIHSS of 3. Patient demographics, clinical features, risk factors, previous medications, imaging and laboratory investigations, final diagnosis, discharge medications, and discharge and 90-day modified Rankin Scale (mRS) were analyzed.

Results

After excluding patients with ICH, mimics, and rare secondary causes, 8,082 patients were available for final analysis (TIAs: 1,357 and stroke: 6,725). In high-risk TIAs, 282 of 666 (42.3%) patients were discharged on DAPT. In patients with minor strokes, 1,207 of 3,572 (33.8%) patients were discharged on DAPT. DAPT was inappropriately offered to 238 of 691 (34.4%) low-risk TIAs and 809 of 3,153 (25.7%) non-minor stroke patients.

Conclusion

This large database of prospectively collected patients with TIAs and stroke shows that, unfortunately, despite several guidelines, a large majority of patients with TIAs and stroke are receiving inappropriate antiplatelet treatment at discharge from the hospital. This requires urgent attention and further investigation.

StrokeClassifier: Ischemic Stroke Etiology Classification by Ensemble Consensus Modeling Using Electronic Health Records

Determining the etiology of an acute ischemic stroke (AIS) is fundamental to secondary stroke prevention efforts but can be diagnostically challenging. We trained and validated an automated classification machine intelligence tool, StrokeClassifier, using electronic health record (EHR) text data from 2,039 non-cryptogenic AIS patients at 2 academic hospitals to predict the 4-level outcome of stroke etiology determined by agreement of at least 2 board-certified vascular neurologists' review of the stroke hospitalization EHR. StrokeClassifier is an ensemble consensus meta-model of 9 machine learning classifiers applied to features extracted from discharge summary texts by natural language processing. StrokeClassifier was externally validated in 406 discharge summaries from the MIMIC-III dataset reviewed by a vascular neurologist to ascertain stroke etiology. Compared with stroke etiologies adjudicated by vascular neurologists, StrokeClassifier achieved the mean cross-validated accuracy of 0.74 (±0.01) and weighted F1 of 0.74 (±0.01). In the MIMIC-III cohort, the accuracy and weighted F1 of StrokeClassifier were 0.70 and 0.71, respectively. SHapley Additive exPlanation analysis elucidated that the top 5 features contributing to stroke etiology prediction were atrial fibrillation, age, middle cerebral artery occlusion, internal carotid artery occlusion, and frontal stroke location. We then designed a certainty heuristic to deem a StrokeClassifier diagnosis as confidently non-cryptogenic by the degree of consensus among the 9 classifiers, and applied it to 788 cryptogenic patients. This reduced the percentage of the cryptogenic strokes from 25.2% to 7.2% of all ischemic strokes. StrokeClassifier is a validated artificial intelligence tool that rivals the performance of vascular neurologists in classifying ischemic stroke etiology for individual patients. With further training, StrokeClassifier may have downstream applications including its use as a clinical decision support system.

Determinants and Temporal Trends of Dual Antiplatelet Therapy After Mild Noncardioembolic Stroke

BACKGROUND

Short-term dual antiplatelet therapy (DAPT) reduces early stroke recurrence after mild noncardioembolic ischemic stroke (NCIS). We aim to evaluate temporal trends and determinants of DAPT prescription after mild NCIS in the Florida Stroke Registry, a statewide registry across Get With The Guidelines-Stroke participating hospitals.

METHODS

In this cross-sectional analysis of a cohort study, we included patients with mild NCIS (National Institutes of Health Stroke Scale score ≤3) who were potentially eligible for DAPT across 168 Florida Stroke Registry participating hospitals between January 2010 and September 2022. Using antiplatelet prescription as the dependent variable (DAPT versus single antiplatelet therapy), we fit logistic regression models adjusted for patient-related factors, hospital-related factors, clinical presentation, vascular risk factors, and ischemic stroke subtype, to obtain adjusted odds ratios (aORs) with 95% CIs.

RESULTS

From 283 264 Florida Stroke Registry ischemic stroke patients during the study period, 109 655 NCIS were considered eligible. Among these, 37 058 patients with National Institutes of Health Stroke Scale score >3 were excluded, resulting in a sample of 72 597 mild NCIS (mean age 68±14 years; female 47.3%). Overall, 24 693 (34.0%) patients with mild NCIS were discharged on DAPT and 47 904 (66.0%) on single antiplatelet therapy. DAPT prescription increased from 25.7% in 2010 to 52.8% in 2022 (β/year 2.5% [95% CI, 1.5%-3.4%]). Factors associated with DAPT prescription were premorbid antiplatelet therapy (aOR, 4.66 [95% CI, 2.20-9.88]), large-artery atherosclerosis (aOR, 1.68 [95% CI, 1.43-1.97]), diabetes (aOR, 1.29 [95% CI, 1.13-1.47]), and hyperlipidemia (aOR, 1.24 [95% CI, 1.10-1.39]), whereas female sex (aOR, 0.83 [95% CI, 0.75-0.93]), being non-Hispanic Black patients (compared with non-Hispanic White patients; aOR, 0.78 [95% CI, 0.68-0.90]), admission to a Thrombectomy-capable Stroke Center (compared with Comprehensive Stroke Center; aOR, 0.78 [95% CI, 0.66-0.92]), time-to-presentation 1 to 7 days from last seen well (compared with <24 h; aOR, 0.86 [95% CI, 0.76-0.96]), and small-vessel disease stroke (aOR, 0.81 [95% CI, 0.72-0.94]) were associated with not receiving DAPT at discharge.

CONCLUSIONS

Despite a temporal trend increase in DAPT prescription after mild NCIS, we found substantial underutilization of evidence-based DAPT associated with significant disparities in stroke care.

Exploring the Association between Low-dose Aspirin Intake and Hyperuricemia in Individuals over 40: A Cross-Sectional Study using NHANES Data (2011-2018)

BACKGROUND Long-term aspirin treatment was recommended for secondary prevention of cardiovascular and cerebrovascular disease. However, some studies reveal low-dose aspirin (LDA) can raise serum uric acid (SUA) levels. Thus, the purpose of this study was to analyze whether LDA intake is associated with hyperuricemia. MATERIAL AND METHODS Data was collected from the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2018. All participants over 40 years old and who selected "preventive aspirin use" were included in the study. Logistic regression analyses were used to evaluate the relationship between LDA intake and hyperuricemia. The stratified analysis was based on race and estimated glomerular filtration rate (eGFR). RESULTS A total of 3540 participants were included in the study. Of them, 805 (22.7%) took LDA, and 190 (31.6%) had hyperuricemia. There was no significant association between hyperuricemia and LDA intake (OR=1.22, 95% CI: 0.97-1.54) after adjusting for confounding factors. However, further subgroup analysis by age showed a significant association between LDA intake and hyperuricemia (OR=3.44, 95% CI: 1.88-6.27) among those 40 to 50 years of age. After adjusting for confounding factors, the relationship was still significant (OR=2.28, 95% CI: 1.10-4.73); we also found that race (Hispanic American, OR=1.84, 95% CI: 1.11-3.06) and eGFR under 60 mL/min/1.73 m² (OR=1.94, 95% CI: 1.04-3.62) may play important roles in the development of hyperuricemia. CONCLUSIONS LDA does not increase the hyperuricemia risk in people over 40 years. However, those aged between 40 and 50 years, Hispanic American, and with impaired renal function should have careful evaluation during LDA treatment.

Antiplatelet treatment patterns and outcomes of secondary stroke prevention in the United States

Objective

Patients who have an ischemic stroke (IS) or transient ischemic attack (TIA) are at risk of having a secondary stroke. Single antiplatelet therapy (SAPT) or dual antiplatelet therapy (DAPT) may be recommended for secondary stroke prevention (SSP), depending on severity and etiology. This study evaluated outpatient antiplatelet treatment patterns for SSP and outcomes after first hospitalization for IS/TIA among adults without atrial fibrillation in the United States.

Materials and methods

This retrospective observational study utilized data from an adjudicated administrative health claims database. Eligible patients had an imputed National Institutes of Health Stroke Scale index event score ≤7. Over-the-counter medication use (eg, aspirin) was not captured.

Results

Of 154,273 patients, 41,622 (27%) were prescribed antiplatelet therapy within 90 days of the event; 93.8% received SAPT, 6.1% received DAPT. The first line of antiplatelet therapy after discharge was started a mean of 17.0 days after the event; mean treatment duration was 61.9 days. The incidence rate for secondary IS was 5.53, 2.03, and 1.17 per person-year 90-days, 1-year, and 3-years following treatment initiation, respectively. Among patients matched for demographic and clinical characteristics, the risk of secondary IS was increased with DAPT versus SAPT (hazard ratio [95% CI]: 1.27 [1.20-1.34]; p < 0.0001).

Conclusions

Many patients were not prescribed or discontinued antiplatelet therapy within 90 days of hospitalization for IS/TIA and, in most cases, prescriptions were not compliant with SSP consensus guidelines. Patients remained at risk for IS, which was highest within 90 days. More effective strategies for SSP are needed to improve outcomes in this patient population.