Trends and Impact of Early Medical Complications in Acute Ischemic Stroke: Data from the Austrian Stroke Unit...

Early medical complications following acute ischemic stroke (AIS) are common and might increase poststroke morbidity and mortality. This study aimed to evaluate trends in the prevalence of early medical complications over almost 2 decades and their impact on 3-month functional outcome and mortality.

A total of 181,704 AIS patients from the Austrian Stroke Unit Registry (2006-2024) were analyzed. Early medical complications included decompensated heart failure, cardiac arrhythmia, sepsis, pneumonia, urinary tract infection (UTI), deep vein thrombosis, and pulmonary embolism. Functional outcomes were assessed using the modified Rankin Scale (mRS) after 3 months, with favorable outcome defined as mRS ≤1. Associations between early medical complications and mRS were analyzed using multivariable Poisson regression models.

Among all patients, 16,279 (9.0%) had early medical complications. Pneumonia (4.2%), UTI (2.9%), cardiac arrhythmia (1.4%), and decompensated heart failure (1.4%) were most common, with significant declines in prevalence over time. Admission NIHSS scores decreased, and the use of intravenous thrombolysis and mechanical thrombectomy increased. Decompensated heart failure (RR = 1.85, 95% CI: 1.73-1.97, p < 0.001), sepsis (RR = 1.75, 95% CI: 1.53-1.99, p < 0.001), pulmonary embolism (RR = 1.67, 95% CI: 1.33-2.10, p < 0.001), and pneumonia (RR = 1.64, 95% CI: 1.57-1.72, p < 0.001) were significantly associated with 3-month mortality. Furthermore, the complications least associated with a favorable outcome were pneumonia (RR = 0.36, 95% CI: 0.32-0.41, p < 0.001), decompensated heart failure (RR = 0.38, 95% CI: 0.32-0.46, p < 0.001), and sepsis (RR = 0.59, 95% CI: 0.45-0.77, p < 0.001). The effect sizes did not change significantly through the observed years.

This study observed a significant reduction in the prevalence of early medical complications after AIS, especially decompensated heart failure, pneumonia, sepsis, and pulmonary embolism which continue to substantially affect mortality and functional outcome in AIS patients.