Abstract 4140089: Lower low-lipoprotein cholesterol level at the time of acute myocardial infarction is associated with increased cardiovascular events

Background: Lipid-lowering therapy for patients with acute myocardial infarction (AMI) is highly recommended, however, a paradox may exist where lower low-density lipoprotein cholesterol (LDL-C) levels at myocardial infarction (MI) are associated with poorer prognoses. Aim: To evaluate the association between baseline LDL-C levels and cardiovascular events after MI. Methods: We studied 1,987 consecutive AMI patients who underwent primary percutaneous coronary intervention and who had available data on preprocedural LDL-C between 1999-2015 at Juntendo University Shizuoka Hospital. Patients were divided into quartiles based on their LDL-C levels. The incidence of major adverse cardiac events (MACE), including all-cause death and recurrent MI up to 5-year, were evaluated. Results: Patients in the lowest LDL-C group were older and had higher prevalence of hypertension, diabetes mellitus and chronic kidney disease. During follow-up, 455 (20.9%) MACE were identified. Cumulative incidence of MACE was significantly higher in the lowest LDL-C group than in other groups (p<0.0001, Figure). After adjustment for other risk factors, the lowest LDL-C group had a significantly higher risk of MACE compared with the highest group (hazard ratio, 1.52; 95% confidence interval, 1.11-2.08; p=0.009). On the other hand, no significant difference in cardiovascular risk was found for patients in the highest LDL-C group compared to patients in the second or third groups. Conclusions: Lower LDL-C level was associated with worse clinical outcomes among patients with MI. Patients with lower LDL-C level have a poor prognosis and require more attention.