Real-world study of low-density lipoprotein cholesterol levels and cardiovascular outcomes in Chinese: A retrospective cohort study in post-percutaneous coronary intervention acute coronary syndrome patients

Background This study aimed to assess the effect of low-density lipoprotein cholesterol (LDL-C) goal attainments (of <2.6 mmol/L and <1.8 mmol/L) on first major adverse cardiovascular events (MACEs) for acute coronary syndrome (ACS) patients who underwent percutaneous coronary intervention (PCI). Methods A retrospective cohort study was conducted using case reviews of post-PCI ACS patients at an acute public hospital in Hong Kong between January 2009 and August 2015. Patients were followed from the date of PCI procedure until the first documented MACE (including all-cause death, myocardial infarction, heart failure, documented unstable angina, revascularization, and stroke) or to the end of the first year. Kaplan-Meier estimates were used to evaluate the impact of LDL-C goal attainments prior to the event on event-free time. Results A total of 1684 patients were identified (79.0% males). At one-year endpoint, 658 (39.1%) attained the LDL-C goal of <1.8 mmol/L, 727 (43.2%) had the LDL-C level between 1.8 mmol/L and 2.6 mmol/L, and 299 (17.8%) had the LDL-C level ≥ 2.6 mmol/L. About 10% experienced a MACE within one year. After adjustment for other available risk factors, attainment of LDL-C goal <2.6 mmol/L was significantly associated with lower rates of MACEs during the one-year follow-up; and those who achieved the LDL-C level of 1.8 mmol/L did not seem to carry any incremental clinical benefits. Conclusions Among post-PCI ACS patients, we merely observed a high correlation between the lipid goal attainment of <2.6 mmol/L and MACEs through one-year follow-up, but not for the goal of <1.8 mmol/L.