Abstract WP152: Is There a “July Effect” on Treatment and Outcomes in Acute Ischemic Stroke - a Nationwide Analysis

Introduction: The “July Effect” is a theoretical decline in quality of care associated with the annual introduction of new trainees at the start of an academic year. In acute ischemic stroke (AIS), a time-critical emergency, any variation in care delivery could significantly impact treatment decisions and outcomes. Therefore, we analyzed treatment patterns and outcomes in July vs non-July AIS to determine if a decline in stroke care from new trainees is a genuine effect or an unfounded concern. Methods: Using the 2022 National Inpatient Sample, we performed a large, retrospective study of hospital discharges for AIS in the United States. Adult patients (≥18 years) hospitalized with AIS were identified using appropriate ICD-10 codes. Non-teaching hospital discharges were excluded. Patients were split into two groups depending on admission month (July vs non-July) and stroke treatments, hospital outcomes and hospital complications were compared. Results: In 2022, there were 548,720 AIS discharges from academic hospitals with 46,230 (8.4%) in July and 502,490 (91.6%) in non-July months. These patients had similar median age (70 vs 70), gender (female 48.3 vs 48.3%), and severity of illness (extreme loss of function 26.2 vs 28.1%). There were similar rates of acute stroke treatments including intravenous thrombolysis (10.8 vs 10.9%) and endovascular thrombectomy (8.2 vs 8.0%) between the two groups. July patients had similar median hospital duration (5 vs 5 days) and median total hospital charges ($69,397 vs $69,963). Interestingly, although the absolute differences are small, July patients had lower hospital mortality (6.9 vs 8.3%, p<0.01) and were more likely to be discharged home (34.1 vs 32.4%, p <0.01). Most complications such as hemorrhagic transformation (6.7 vs 6.8%) and acute kidney injury (22.3 vs 23.0%) were similar, but July patients had lower rates of sepsis (8.3 vs 9.5%, p<0.01) and pneumonia (7.5 vs 8.8%, p <0.01). Conclusions: July stroke patients had similar rates of acute stroke therapies as well as similar outcomes and complications. Therefore a “July Effect” in stroke care appears to be a myth. These findings reflect the resilience of modern stroke systems at academic centers. *Automated assistive writing technologies and tools were used for editing and formatting the abstract. The study design, analysis and conclusion were developed entirely by the authors.