TORONTO — In the second year after the new Accreditation Council for Graduate Medical Education duty-hours rules became effective, mortality in patients hospitalized for four common medical conditions—acute myocardial infarction, heart failure, gastrointestinal bleeding, and stroke—were significantly reduced at more-teaching-intensive hospitals, compared with less-teaching-intensive hospitals.
This apparent survival benefit was not seen for surgical patients. No changes in mortality were seen in surgical patients during either the first or second year post reform, Dr. Kevin Volpp and his colleagues at the Philadelphia VA Medical Center and the University of Pennsylvania, Philadelphia, reported at the annual meeting of the Society of General Internal Medicine.
The Accreditation Council for Graduate Medical Education (ACGME) duty-hour reform policy went into effect in July 2003. Designed to improve patient safety, the rules limit the number of hours residents can work to 80 per week, with a minimum of 10 hours of time off between shifts.
The study cohort included all unique patients (n=320,685) admitted to acute-care VA hospitals between July 2000 and June 2005 with principal diagnoses of acute myocardial infarction (AMI), heart failure, gastrointestinal bleeding, stroke, or Diagnosis-Related Group classification of general, orthopedic, or vascular surgery.
Logistic regression analysis was used to examine the change in mortality for patients in more- versus less-teaching-intensive hospitals before and after duty-hour reform. The primary study outcome was all-cause mortality within 30 days of hospital admission.
In the first year after duty-hour reform, no significant relative changes in death rates were reported for either the medical or surgical patients. In the second year, a significant 26% reduction in mortality risk was seen at the more-teaching-intensive hospitals for patients with any of the four medical conditions. That change was predominantly driven by a highly significant 52% relative reduction in mortality risk in AMI patients.
For patients in hospitals in the 75th percentile of teaching intensity, mortality improved from prereform year 1 to postreform year 2 by 0.70 percentage points—or a relative improvement of 11.1% for medical patients—compared with patients in hospitals in the 25th percentile of teaching intensity, Dr. Volpp said.
At hospitals in the 90th percentile of teaching intensity, the improvement in mortality was even greater: about 0.88 percentage points, or a relative improvement of about 14%, compared with hospitals in the 10th percentile of teaching intensity.
Dr. Volpp noted during his presentation that the study was limited because “we don't have any information on compliance with the ACGME rules or actual number of hours worked.”
VA hospitals are the largest single site for residency training in the United States, Dr. Volpp noted. Ongoing studies are assessing mortality and other outcomes in non-VA settings, he added.
The study was funded by the VA Health Services Research and Development Service.