UMKC study finds beta blockers can increase risk of death in noncardiac surgery

Mark Friedell, M.D.

A University of Missouri-Kansas City School of Medicine research study has found that unless they have serious cardiac issues, patients should question the need for a beta blocker before an upcoming major surgery.

The controversial practice of administering pre-surgery beta blockers to patients having noncardiac surgery is associated with an increased risk of death in patients with no heart risk factors, according to a new report released in the May 17, 2015 issue of  JAMA Surgery. Mark L. Friedell, M.D., chairman of surgery, is the lead author of the article.

Beta blockers are beneficial for patients with three to four cardiac risk factors, according to the report. But pre-surgery beta blockers are commonly given to patients having cardiac surgery.

Beta blockers are medications that reduce blood pressure and work of the heart by blocking the effects of adrenaline. They are regularly prescribed to treat various cardiac diseases, high blood pressure, glaucoma and migraines.  Beta blockers make the heart beat more slowly and with less force.

“This is very important. Anyone on a daily beta blocker for any reason should stay on the beta blocker before surgery. It should not be stopped,” Friedell said. “This is the consensus of the cardiology societies in the United States.”

But use in patients undergoing noncardiac surgery is controversial because of the increased risk of low blood pressure and stroke. Because of the persistent controversy, Friedell and coauthors analyzed data from the Veterans Health Administration to examine the effect of pre-surgery beta blockers on patients having noncardiac surgery by measuring 30-day surgical mortality.

The analysis included 326,489 patients: 314,114 (96.2 percent) had noncardiac surgery and 12,375 (3.8 percent) had cardiac surgery. Overall, 141,185 patients (43.2 percent) received a beta blocker. Of the patients having cardiac surgery, 8,571 (69.3 percent) received a beta blocker and 132,614 (42.2 percent) of the patients having noncardiac surgery got one.

The results suggest that among patients with no cardiac risk factors having noncardiac surgery, those patients receiving beta blockers were significantly more likely to die than those not receiving beta blockers. The risk of death decreased for those patients with one to two risk factors but the reduction was not significant.  However, for patients having noncardiac surgery with three to four cardiac risk factors, those receiving beta blockers were significantly less likely to die than those not receiving beta blockers, the authors found. They did not observe similar results in patients having cardiac surgery.

“Most important, the use of beta blockers in patients with no cardiac risk factors appears to be associated with a higher risk of death, which has, to our knowledge, not been previously reported,” the study concludes.

In 2012, Friedell joined the UMKC School of Medicine as the Ralph R. Coffey Endowed Chair. He is renowned for his knowledge in vascular surgery, general surgery and surgical education.