Talk about head-scratchers. High-risk patients admitted to teaching hospitals for heart failure and cardiac arrest didn’t appear to be the worse for wear if treated during the two largest cardiology meetings in the U.S. In fact, they had lower 30-day mortality rates while patients admitted for acute MI received more conservative care with no drop in survival.
The findings were published online Dec. 22 in JAMA Internal Medicine.
Anupam B. Jena, MD, of the healthcare policy department at Harvard Medical School in Boston, and colleagues explored the outcomes in mortality and treatment of patients during the periods when the American College of Cardiology and the American Heart Association conduct their annual scientific sessions. The meetings’ attendance has ranged from 13,000 to 19,000 over the years.
Jena et al analyzed Medicare data on patients hospitalized between 2002 and 2011 for acute MI, heart failure and cardiac arrest during meeting dates as well as identical days three weeks before and after the meeting dates. They also focused on factors such as teaching or nonteaching hospital status and the patient risk level. Their primary outcome was all-cause 30-day mortality after admission.
Patients admitted during meetings had similar characteristics to those hospitalized in the control groups, and hospitalizations were evenly distributed during all periods. After adjustments, the 30-day mortality rate for high-risk heart failure patients admitted to teaching hospitals was lower during meetings (17.5 vs. 21.2 percent) as was the rate for cardiac arrests (59.1 vs. 69.4 percent).
They found no difference at teaching hospitals in the adjusted mortality rates for high-risk acute MI patients and in low-risk patients. High-risk patients admitted with acute MI during meetings had lower adjusted PCI rates, though, at 20.8 percent vs. 28.2 percent during nonmeeting periods; 30-day mortality rates were similar for the two groups.
Jena et al also conducted a series of sensitivity analyses and found no evidence of unmeasured confounding.
They admitted that they could not pinpoint the mechanism behind the difference in mortality rates but they proposed some possible explanations: Cardiologists who remained to treat patients might be different from those at the meeting; same-day elective procedures and outpatient visits may have been put on pause during meetings, giving the hospital-bound cardiologists more time to concentrate on high-risk patients; or physicians may have been reluctant to proceed with procedures in high-risk patients without what they perceived to be adequate backup.
“Interventions foregone during meeting dates are more likely to be those for which the risk-benefit tradeoff is less clear and may involve harms that outweigh benefits in high-risk patients,” they wrote. “Our finding that substantially lower PCI rates for high-risk patients with AMI [acute MI] admitted to teaching hospitals during cardiology meetings are not associated with improved survival suggests potential overuse of PCI in this population.”