Temporal trends in management and outcome of patients with acute coronary syndrome according to admission low-density lipoprotein cholesterol levels

Background The importance of differences in baseline low-density lipoprotein cholesterol (LDL-C) levels and pretreatment with statins on the temporal improvement in outcome of acute coronary syndrome (ACS) patients has not been studied yet. Methods Patients were divided into two groups according to baseline LDL-C levels: LDL-C <130mg/dl and LDL-C ≥130mg/dl. Baseline characteristics, clinical data and outcomes were compared for each LDL-C group between patients enrolled in early (2000–2006), mid (2008–2010) and recent (2013–2016) surveys. Results The study population was comprised of 8343 patients. Patients with LDL-C <130mg/dl were older and were more commonly pretreated with aspirin and statins compared to patients with LDL-C ≥130mg/dl. Patients included in recent surveys were more frequently selected for an invasive strategy with coronary angiography and subsequent revascularization, and were more commonly treated with guideline-based medical therapy. For patients with a LDL-C ≥130mg/dl, the temporal improvements in therapy were associated with lower 1-year mortality rates (7.2, 4.4 and 3.5% for patients in early, mid and late surveys, respectively, P = 0.006). That temporal improvement in outcomes existed only in statin-naïve patients. For patients with LDL-C <130 mg/dl, temporal improvement in treatment was not accompanied by a reduction in 30 day or 1-year mortality rates. Conclusion Treatment of ACS patients has improved over the past decades regardless of LDL-C levels. This improvement was accompanied by lower mortality rates in ACS patients with LDL-C ≥130 mg/dl, but not in patients with LDL-C <130mg/dl.