Trends in Ischemic Stroke Hospitalization and Outcomes in the United States Pre- and Peri-COVID-19 Pandemic: A National Inpatient Sample Study

<b>Background/Objectives:</b> The COVID-19 pandemic impacted healthcare systems globally, disrupting the management and treatment of acute ischemic stroke (AIS). Understanding how AIS admissions, treatments, and outcomes were affected is critical for improving stroke care in future crises. The objective of this work was to assess the COVID-19 pandemic's impact on AIS admissions, treatment patterns, complications, and patient outcomes in the U.S. from 2016 to 2021, focusing on differences between pre-pandemic (2016-2019) and peri-pandemic (2020-2021) periods. <b>Methods:</b> This is a retrospective cohort study using the National Inpatient Sample (NIS) database, analyzing weighted discharge records of AIS patients over six years. Data encompass U.S. hospitals, including urban, rural, teaching, and non-teaching facilities. The study included AIS patients aged 18 and older (N = 3,154,154). The cohort's mean age was 70.0 years, with an average hospital stay of 5.1 days and an adjusted mean cost of $16,765. Men comprised 50.5% of the cohort. We analyzed temporal trends in AIS hospitalizations from 2016 to 2021, comparing pre- and peri-COVID-19 periods. The primary outcome was the AIS admissions trend over time, with secondary outcomes including reperfusion therapy utilization, intubation rates, discharge disposition, and complications. Trends in risk factors and NIH Stroke Scale (NIHSS) severity were also evaluated. <b>Results:</b> AIS admissions rose from 507,920 in 2016 to 535,694 in 2021. Age and sex distribution shifted, with a growing proportion of male AIS cases (from 49.8% to 51.4%) and a decrease in mean age from 70.3 to 69.7 years. Although not statistically significant, White patients were the majority (68.0%), though their proportion declined as Black, Hispanic, and Asian/Pacific Islander cases increased. Reperfusion therapy, especially mechanical thrombectomy, rose from 2.2% to 5.6% over the study period. Intubation rates increased from 4.8% pre-COVID-19 to 5.5% peri-COVID, with higher rates among COVID-positive patients. NIHSS severity declined over time, with severe strokes (NIHSS ≥ 16) decreasing from 14.5% in 2017 to 12.6% in 2021. <b>Conclusions:</b> The COVID-19 pandemic brought significant shifts in AIS patterns, with younger, more diverse patients, increased reperfusion therapy use, and rising complication rates. These changes underscore the importance of resilient healthcare strategies and resource allocation to maintain stroke care amid future public health emergencies.