Relationship between stress hyperglycemia ratio and gastrointestinal bleeding and mortality after coronary artery bypass grafting: a multicenter cohort study.

Background: Gastrointestinal bleeding after coronary artery bypass grafting (GIBCG) is a serious postoperative complication linked to increased mortality. The stress hyperglycemia ratio (SHR) has been recognized as a reliable predictor of adverse clinical outcomes, particularly in patients with cardiovascular disease. This study aimed to investigate the association between SHR and both GIBCG and in-hospital mortality. Methods: Patients were recruited from four medical centers and the Medical Information Mart for Intensive Care IV, with a total of 16,440 individuals included in the final analysis. Patients were categorized into four groups based on SHR quartiles. The primary outcomes of interest were the incidence of GIBCG and in-hospital mortality. Restricted cubic splines and logistic regression models were employed to analyze the relationship between SHR and clinical outcomes. Results: Among the patients who underwent surgery, 1,158 (7.04%) experienced GIBCG, while 214 (1.3%) died during hospitalization. After adjusting for confounding variables, a U-shaped relationship was observed between SHR and both GIBCG occurrence and in-hospital mortality. The lowest incidence of these outcomes was observed within the SHR range of 0.706-0.792, with inflection points identified at 0.71 for GIBCG and 0.733 for in-hospital mortality. Conclusion: A U-shaped relationship was identified between SHR and both GIBCG and in-hospital mortality. Both low and high SHR levels may help identify patients at increased risk of gastrointestinal bleeding and in-hospital mortality following coronary artery bypass grafting.