Relationship between low-density lipoprotein levels on admission and 1-year outcome in patients with acute ST-segment-elevation myocardial infarction

Abstract

This study assessed the relationship between low-density lipoprotein cholesterol (LDL-C) levels on admission and the incidence of major adverse cardiovascular events (MACE) in patients with acute ST-segment-elevation myocardial infarction (ASTEMI). Patients with ASTEMI who had a lipid profile tested within 24 hours of symptom onset were enrolled. They were stratified into high and low LDL-C groups according to whether their LDL-C was above (n = 501) or below (n = 575) the median level, respectively. The incidence of MACE, cardiovascular death, non-fatal MI, revascularization, and stroke was compared between the groups at 1 month, 6 months, and 1 year. Survival analysis and Cox proportional hazard analysis were performed. In-hospital use of beta blockers was better in the high than in the low LDL-C group (76.6% vs. 69.7%, p = 0.01). Statin use was significantly higher in the high than in the low LDL-C group during follow-up (86.8% vs. 80.0%, p = 0.003 at1 month; 71.6% vs. 62.4%, p = 0.002 at 6 months; 67.8% vs. 61.2%, p = 0.03 at 1 year). The incidence of MACE on follow-up at 1 month was higher in the low than in the high LDL-C group (12.0% vs. 8.1%, p = 0.04). At 1 year, survival was not significantly different between the groups. Cox proportional hazards analysis indicated that the incidence of MACE was significantly associated with hypertension, current smoking, high-density lipoprotein cholesterol (HDL-C), in-hospital use of beta blockers, and statin use on follow-up (p < 0.01). LDL-C levels on admission in patients with ASTEMI had no significant effect on the 6-month and 1-year incidence of MACE, but the incidence of MACE was significantly higher in the low LDL-C group at 1 month. It would be relevant to further investigate the HDL-C level on admission, in-hospital use of beta blockers, and statin use during follow-up in relation to MACE.