Clinical impact of ≥50% reduction of low density lipoprotein cholesterol following lipid lowering therapy on cardiovascular outcomes in patients with acute coronary syndrome

Abstract

Background: Current guidelines advocate achieving a fixed low-density lipoprotein cholesterol (LDL-C) target and ≥50% reduction in LDL-C levels. However, sufficient LDL-C reduction is often not achieved even in patients achieving a fixed LDL-C target.

Objective: This study investigated the clinical impact of insufficient LDL-C reduction following lipid lowering therapy on cardiovascular outcomes in acute coronary syndrome (ACS) patients.

Methods: A total of 561 consecutive ACS patients who had undergone percutaneous coronary intervention (PCI) and LDL-C level measurement at index PCI and 12 months afterwards were evaluated retrospectively. We investigated a relationship between ≥50% LDL-C reduction and cardiovascular events including the composite of cardiac death, myocardial infarction, target vessel revascularization and stent thrombosis.

Results: Of the patients, 145 (25.8%) achieved ≥50% LDL-C reduction within 12 months. There were no significant differences in cardiovascular events between patients achieving the LDL-C target of 55 mg/dL and those not achieving it (23.6% vs 19.3%, P = .77), whereas the incidence of cardiovascular events was higher in the <50% LDL-C reduction group than the ≥50% LDL-C reduction group (26.0% vs 12.4%, P = .009). Even in patients with LDL-C < 55 mg/dL, cardiovascular events were more frequently in the <50% LDL-C reduction group than the ≥50% LDL-C reduction group (28.8% vs 13.2%, P = .04). Cox proportional hazard models revealed that <50% LDL-C reduction was an independent predictor of cardiovascular outcomes (hazard ratio: 2.03, 95% CI: 1.23-3.36).

Conclusion: The current study underscores the significance of achieving ≥50% LDL-C reduction in addition to a target of 55 mg/dL in preventing additional cardiovascular events in ACS patients.

Keywords: Heterogeneity in statin response; LDL-C; Lipid lowering therapy; ≥50% reduction of LDL-C.