Gender-based association between high-density lipoprotein cholesterol and adverse outcomes after coronary artery bypass grafting

Background: High-density lipoprotein cholesterol (HDL-C) is shown to be an independent protective factor against coronary artery diseases (CAD). Yet there are limited studies focusing on the association between HDL-C and coronary artery bypass graft (CABG) surgery outcomes. Hypothesis Low levels of HDL-C are associated with higher incidence of adverse outcomes in patients undergoing CABG. Methods This registry-based study included 17,772 patients who underwent elective isolated CABG between 2007 and 2017. Participants were assigned into low and optimal HDL-C groups based on serum HDL-C levels at admission and were followed for one year after surgery. Cox proportional hazard models were performed to evaluate the association between HDL-C levels and incidence of mortality as well as major adverse cardiovascular and cerebrovascular events (MACCE), while adjusting for potential confounders. Moreover, participants were stratified based on gender and the association was also investigated in each subgroup separately. Results No significant difference was found between the groups regarding incidence of both mortality and MACCE, after adjusting with IPW [HR (95%CI): 1.109 (0.815–1.509) and HR (95% CI): 1.192 (0.995–1.428), respectively]. According to the gender-based subgroup analysis, low HDL-C group exhibited higher MACCE incidence solely in the male subgroup, after adjusting with IPW. Conclusion The association between perioperative HDL-C level and incidence of MACCE during 1-year post-CABG surgery in the male subgroup suggests HDL-C level as a possible prognostic factor in this population. Further studies are warranted to clarify the role of HDL-C level in predicting the prognosis of patients undergoing CABG.