Low ALT levels are associated with poor outcomes in acute coronary syndrome patients admitted to the intensive cardiac care unit

Abstract Background Frailty is an under recognized and important entity that bears worse prognosis. Purpose Although low serum alanine aminotransferase (ALT) can serve as a novel marker of frailty, its use was never assessed in acute coronary syndrome (ACS) patients. Methods A retrospective analysis of hospitalized ACS patients in the intensive cardiac care unit (ICCU) between 1/5/2011 and 1/12/2020 at a single tertiary medical center. Results The study included 3956 patients after excluding patients with ALT >40 IU/L, cirrhosis and missing data, followed for a median duration of 47 months (IQR 20–77). Patients were stratified into two groups based on their first ALT measurement within the index hospitalization: low-normal ALT group (ALT ≤10 IU/L) vs. high-normal ALT group (ALT >10 IU/L). Patients with ALT≤10 IU/L were older (mean age 71 vs. 65, P