National assessment of early β-blocker therapy in patients with acute myocardial infarction in China, 2001-2011: The China Patient-centered Evaluative Assessment of Cardiac Events (PEACE)-Retrospective AMI Study

Abstract

Background: Since 2007, clinical practice guidelines have recommended β-blocker therapy early in the course of acute myocardial infarction (AMI) for patients who are not at high risk for complications. Our objective was to perform a national quality assessment of early β-blocker use during hospitalization for AMI over the past decade in China.

Methods: We conducted medical record review of a nationally representative sample of patients admitted to Chinese hospitals with AMI and studied those without absolute contraindications to β-blocker therapy in 2001, 2006, and 2011. We evaluated the use, type, and dose of β-blockers within the first 24 hours of admission over time and identified predictors of not using this treatment both in ideal candidates and in those with risk factors for cardiogenic shock.

Results: Among 14,241 patients with AMI (representing 43,165 patients in 2001, 106,167 patients in 2006, and 221,874 patients in 2011 in China, respectively), 45.1% had no contraindications to early β-blocker therapy; 21.1% had risk factors for cardiogenic shock but no absolute contraindication. β-blocker use in ideal patients was 54.3% in 2001, 67.8% in 2006, and 61.8% in 2011 (P = .28 for trend). Predictors of nontreatment were older age, lower systolic blood pressure, lower heart rate, absence of chest discomfort, and admission to a nonteaching hospital. Use in patients with risk factors for cardiogenic shock was 42.6% in 2001, 59.5% in 2006, and 52.9% in 2011 (P = .31 for trend). Metoprolol was used most frequently (91.5%), but dosages were often below those recommended in guidelines.

Conclusions: The use of early β-blocker therapy for patients with AMI in China is suboptimal, with underuse in patients who could benefit and substantial use among those who might be harmed. Patterns of use have not changed over time, thus creating an important target of efforts to improve quality of care for AMI.

Trial registration: ClinicalTrials.gov NCT01624883.

Conflict of interest statement

Disclosures: There are no relevant conflicts of interest.

Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Flowchart of the random sampling and study cohorts.

Figure 2

Temporal trends in early beta-blocker use (weighted) in overall patients with AMI (n=6426), ideal patients (n=3419) and high-risk patients (n=3007), 2001–2011.

Figure 3

Temporal trends in early beta-blocker use (unweighted) in ideal patients (A) and high-risk patients (B) in strata of rural and urban hospitals, 2001–2011.

Figure 3

Temporal trends in early beta-blocker use (unweighted) in ideal patients (A) and high-risk patients (B) in strata of rural and urban hospitals, 2001–2011.

Figure 4. Factors associated with early beta-blocker use in the ideal cohort (n=3419)

Variables having significant association with early beta-blocker use are shown along the vertical axis. The strength of effect is shown along the horizontal axis with the vertical line demarking an odds ratio of 1 (that is, no association); estimates to the right (that is, > 1) are associated with greater likelihood of early beta-blocker use, while those to the left (that is,

Figure 5. Type and dosage of oral beta-blockers

Dosage distribution of metoprolol in each year is shown as the cumulative oral dose administered within the first 24 hours of admission. The numbers of patients using atenolol, bisoprolol or other beta-blockers was small and thus only the proportions of total use are shown. Others including propranolol, carvedilol and arotinolol.