Patient selection Institutional Review Board approval was obtained. No informed consent was required. We included patients hospitalized for at least 7 days with SAH7, 8 between December 1, 2016 and June 30, 2022 in our tertiary-level hospital. By only including patients who stayed at least 7 days, we excluded the patients with very mild SAH who were discharged before 7 days and patients with very severe SAH who died or were converted to comfort care within 7 days.