Using beta-blockers after elective PCI does not improve cardiovascular outcomes in older adults

The use of beta-blockers in older adults with stable angina who underwent PCI did not reduce the adjusted mortality rate, MI, stroke or revascularization, according to retrospective, observational registry analysis.

However, after three years, patients who received beta-blockers at hospital discharge had higher rates of heart failure readmissions.

Lead researcher Apurva A. Motivala, MD, of Columbia University in New York, and colleagues published their results online in the Journal of the American College of Cardiology: Cardiovascular Interventions on Aug. 15.

The researchers noted that the American College of Cardiology and American Heart Association gave a Class 1 recommendation for the use of beta-blockers for patients with coronary artery disease, MI or systolic heart failure. Beta-blockers are also recommended as first-line therapy for patients with coronary artery disease with stable angina without prior MI or systolic heart failure and for patients with coronary artery disease and hypertension.

For this study, they evaluated 755,215 patients from 1,443 sites who underwent elective PCI between January 2005 and March 2013 from hospitals enrolled in the National Cardiovascular Data Registry CathPCI registry. All patients had stable angina and had no prior history of MI, left ventricular systolic dysfunction, CABG or systolic heart failure.

The mean age was 65.5 years old, while 64.3 percent of patients were males and 85.1 percent were Caucasians.

Further, 71.4 percent of patients were prescribed beta-blockers when discharged from the hospital. Patients who received beta-blockers were younger, more likely to be female and more likely to have a history of hypertension, diabetes, dyslipidemia, smoking, dialysis, prior PCI and prior and current heart failure.

The use of beta-blockers in these patients increased during the eight years of the study.

After three years of follow-up, the unadjusted crude mortality rate was 16.3 percent among the patients who were at least 65 years old and had longitudinal claims data from the Centers for Medicare & Medicaid Services (CMS). 

During the follow-up period, the adjusted mortality rate was 14.0 percent in patients receiving a beta-blocker prescription and 13.3 percent in patients not receiving a beta-blocker prescription. Meanwhile, the rates of MI were 4.2 percent and 3.9 percent, respectively; the rates of stroke were 2.3 percent and 2.0 percent, respectively; and the rates of revascularization were 18.2 percent and 17.8 percent, respectively. None of the differences were statistically significant.

In addition, after three years, 8.0 percent of patients in the beta-blocker group and 6.1 percent of patients in the other group were readmitted to the hospital for heart failure. That difference was statistically significant.

The researchers mentioned a few potential limitations of the study, including that they only evaluated patients who were at least 65 years old and had CMS linkage data available. They also did not have access to drug claims data or information of angina frequency and severity. In addition, they noted they could not adjust for residual confounding factors.

“These hypothesis-generating findings highlight patient features associated with the use of beta-blockers such as hypertension and prior/current [heart failure] that often track with symptomatic coronary artery disease that prompts elective PCI, and suggest that the use of beta-blockers in this population should be customized based on other concomitant cardiovascular conditions and completeness of revascularization,” the researchers wrote.