Ezetimibe Use and LDL-C Goal Achievement: A Retrospective Database Analysis of Patients with Clinical Atherosclerotic Cardiovascular Disease or Probable Heterozygous Familial Hypercholesterolemia

Abstract

Background: Ezetimibe is recommended by clinical practice guidelines as a second-line therapy for lowering low-density lipoprotein cholesterol (LDL-C) levels, but little is known about its use and effectiveness in real-world populations.

Objective: To understand the real-world impact of adding or switching to ezetimibe on LDL-C goal achievement in patients with clinical atherosclerotic cardiovascular disease (ASCVD) and/or heterozygous familial hypercholesterolemia (HeFH).

Methods: Patients aged ≥ 18 years with an LDL-C measurement available between January 1, 2013, and June 30, 2014, were identified using the Inovalon MORE ² database; this included commercial, health insurance exchange, Medicare Advantage, and managed Medicaid patients. The index date was the date of the first LDL-C measurement. Patients were required to have evidence of clinical ASCVD or probable HeFH based on ICD-9-CM codes and ≥ 1 outpatient pharmacy claim for a statin in the 1-year pre-index period, as well as continuous medical and pharmacy coverage for 1 year pre- and post-index. Patients who added ezetimibe to existing statin therapy or switched to ezetimibe within 90 days post-index LDL-C measurement were identified in order to replicate the typical time a clinician takes to assess the use of ezetimibe. The primary outcome was the proportion of patients who met the LDL-C goal of < 70 mg/dL within the follow-up period. LDL-C goal achievement was evaluated by baseline LDL-C level groupings: < 70 mg/dL, 70-99 mg/dL, 100-129 mg/dL, or ≥ 130 mg/dL; and across 4 patient diagnosis categories: all patients, ASCVD only, probable HeFH only, and ASCVD and probable HeFH. Descriptive analyses were reported. Categorical variables were summarized as the number of and corresponding percentage of patients. Continuous variables were presented as the mean and SD of the number of observations and median and range where appropriate.

Results: Of 125,330 patients who met selection criteria, mean age was 70.1 (SD = 9.9) years and mean LDL-C baseline was 90.7 (SD = 34.0) mg/dL. Over one half of patients (70%) were receiving statin therapy. Within the post-index time frame, 1.05% (n = 1,309) of patients added or switched to ezetimibe. Of these, 26% achieved LDL-C goal during the 90-day follow-up (59.5% did not achieve goal and 14.4% did not have a follow-up lab value). Therapeutic targets were reached by 30% of patients with baseline LDL-C levels of 70-99 mg/dL; 14% of those with baseline LDL-C of 100-129 mg/dL; and 7% of those with baseline LDL-C of ≥ 130 mg/dL. Achievement of LDL-C goals also varied by baseline diagnosis category.

Conclusions: The addition of or switch to ezetimibe therapy was associated with a relatively small percentage of LDL-C goal achievement (< 70 mg/dL) in patients with clinical ASCVD and/or HeFH, even among patients with baseline LDL-C between 70 and 99 mg/dL. To provide superior individualized care for patients with hyperlipidemia, there is a potential role for newer therapies in lipid lowering, such as PCSK9 inhibitors, in appropriate high-risk populations.

Disclosures: This study was sponsored by Amgen. Menzin, Yu, and Stern are employees of Boston Health Economics, which was contracted by Amgen to perform this study. Aggarwal is a former employee of Boston Health Economics. Boatman, Patel, and Harrison are employees and stockholders of Amgen. Study concept and design were contributed by Menzin, Aggarwal, Harrison, and Patel. Aggarwal, Stern, and Yu collected the data. Data interpretation was performed by Aggarwal, Harrison, Patel, and Boatman. The manuscript was written and revised primarily by Aggarwal, with assistance from the other authors.

FIGURE 1

Timeline Analysis for Describing LDL-C Levels Among Statin Users After Adding or Switching to Ezetimibe

FIGURE 2

Patient Selection