Low Postoperative Cholesterol Level Is Associated with Adverse Outcomes After Coronary Artery Bypass Grafting

Abstract

Low cholesterol levels have been linked to severe illness, including sepsis. This study evaluated whether early postoperative cholesterol levels are associated with adverse outcomes in patients after elective Coronary Artery Bypass Grafting with extracorporeal circulation. This retrospective single-center study included 3280 adults who had at least one cholesterol measurement within the first five postoperative days. The lowest cholesterol value was analyzed with demographic, comorbidity, intraoperative, and laboratory variables to assess associations with 30-day mortality, cerebrovascular accident, renal replacement therapy, and respiratory dysfunction. ROC analysis with Youden’s Index identified an optimal cut-off, and logistic regression determined independent associations. A cholesterol cut-off of 2.46 mmol/L best stratified 30-day mortality (AUC 0.716; 95% CI 0.657–0.775), with patients below this threshold showing higher mortality (3.9% vs. 1.2%; p < 0.001). Cholesterol < 2.46 mmol/L was independently associated with 30-day mortality (OR 2.759 (1.675–4.544); p < 0.001), cerebrovascular accident (OR 3.661 (1.271–10.540); p = 0.016), renal replacement therapy (OR 4.785 (1.809–12.658); p = 0.002), and respiratory dysfunction (OR 3.039 (1.648–5.602); p < 0.001). Early postoperative hypocholesterolemia shows concurrent associations with adverse outcomes after CABG. Cholesterol levels < 2.46 mmol/L are concurrently associated with higher 30-day mortality.