ABSTRACT NUMBER: ESOC2026A1621 SHORT- AND LONG-TERM SURVIVAL AFTER ANEURYSMAL SUBARACHNOID HEMORRHAGE IN KAZAKHSTAN: A NATIONAL COHORT STUDY

Abstract Background and aims Aneurysmal subarachnoid hemorrhage (aSAH) is a severe form of stroke associated with high early and long-term mortality. Data on survival after aSAH at the national level remain limited in Central Asia. This study aimed to assess short- and long-term survival after aSAH in Kazakhstan. Methods Nationwide inpatient hospitalization data were used for analysis. Survival time was defined as the interval from hospital admission to death. Patients who were alive at the end of the study period or without recorded date of death were censored at the end of follow-up. Kaplan-Meier methods were used to estimate survival probabilities and cumulative mortality at 30 days, 1 year, and 5 years after admission. Cox regression was used for exploratory assessment of associations with mortality. Results Overall survival at 30 days was 72.8%, declining to 66.5% at 1 year and 57.4% at 5 years after hospital admission. At 30 days, survival was higher in women than in men (73.4% vs. 72.2%). This difference persisted at 1 year (67.2% vs. 65.7%) and at 5 years (59.1% vs. 55.7 (log-rank χ2=15.70, p=0.0001). At 5 years, survival ranged from 77.5% in those aged 19-30 years to 31.7% in patients aged 71-80 years (log-rank χ2=1340.46, p<0.001). Cox regression showed higher mortality in men (HR 1.24; 95% CI 1.17-1.31) and a strong age effect, with an approximately 3% increase in risk per year of age. Conclusions These findings highlight the substantial burden of aSAH in Central Asia and underscore the need for improved prevention and acute management strategies. Conflict of interest Karashash Menlibayeva: nothing to disclose. Chingiz Nurimanov: nothing to disclose. Iroda Mammadinova: nothing to disclose. Lu Liu: nothing to disclose. Owase Jeelani: nothing to disclose. Serik Akshulakov: nothing to disclose. Yanzhong Wang: nothing to disclose.