Abstract 12870: Absence of LDL Measurement in Secondary Prevention is Associated With Increased Subsequent Major Adverse Clinical Event (MACE) That is Only Partially Mitigated by Statin Use

Abstract

Introduction: There has been considerable discussion regarding the value of follow-up LDL-C measurements in secondary prevention of major adverse cardiac events (MACE). We therefore set out to determine in a large healthcare system whether measurement of LDL-C after an ASCVD event was associated with a difference in MACE during follow-up and whether differences in outcomes could be attributed to differences in statin use. Methods: The Intermountain Enterprise Data Warehouse was searched to identify all adults with a first encounter for ASCVD-including coronary artery disease (CAD), cerebrovascular disease (CVD), and peripheral arterial disease (PAD)—between January 1, 1995 and December 31, 2016 who survived the index event and were followed for ≥3 years or until death. Results: Patients (N=68,411) had an average age of 66±14 years; 65% were men; 70.3%, 21.0%, and 8.6% entered with CAD, CVD, and PAD, respectively. A statin was prescribed to 52% of patients during follow-up. A total of 33,698 (49%) did not have and 34,713 (51%) did have a follow-up LDL-C test prior to a subsequent MACE (death, MI, CVA, and revascularization) or end of follow-up. By 3 years, MACE occurred in 14,835 (37.4%) vs. 5,770 (20.1%) of those without vs. with an LDL-C measurement, respectively (Figure top). The multivariable hazard ratio for 3 year MACE based on measuring LDL-C was 0.47. The increased MACE rate associated with not measuring LDL-C was partially mitigated by statin use (Figure bottom). Only 44.7% vs. 58.9% of patients without vs. with LDL-C measurement were taking statins. Conclusion: These data indicate that there is a significant and clinically meaningful difference in MACE based on a follow-up measurement of LDL-C. Statin administration partially, but not completely mitigated the increased MACE rate. While these results are limited in that they are from a retrospective registry, they indicate that LDL-C should be measured, and statin should be administered after an initial ASCVD event.