News:Changes in Residents’ Hours of Work Not Generally Reflected in Improved Outcomes

September 10, 2007 by Grendel Burrell [mailto:grendel.burrell@gmail.com]

On July 1, 2003, the Accreditation Council for Graduate Medical Education (ACGME) implemented duty hour regulations for all ACGME-accredited residency programs due in large part to concern over widely publicized medical errors (Accreditation Council for Graduate Medical Education Web site. Resident duty hours language: final requirements. http://www.acgme.org). Work restrictions for residents included no more than 80 hours per week, with 1 out of 7 days free of all hospital responsibilities, averaged over 4 weeks, and no more than 24 continuous hours with an additional 6 hours for education and transition of care. Residents were also restricted to in-house call no more frequently than every third night with at least 10 hours of rest between work periods. This represented a massive change from the days of being on call every other night or every third night with the expectation of a full day’s work after the night on call.

However, differences of opinion remain about whether the regulations are appropriately designed, whether the rules benefit patient care, adversely effect patient care, or even go far enough to limit the hours of work for physicians in training programs. In 1989, New York implemented similar reforms to residents’ work hours, and these changes were not associated with changes in mortality rates for patients with heart failure, pneumonia or myocardial infarction [4]. A statewide analysis of the effect of New York's regulations, limiting internal medicine and family practice residents' work hours, on patient mortality was conducted as a retrospective study of inpatient discharge files for 1988 (before the regulations) and 1991 (after the regulations). 170,214 adult patients discharged from New York teaching hospitals and 143,455 from nonteaching hospitals with a principal diagnosis of congestive heart failure (CHF), acute myocardial infarction (AMI), or pneumonia, for the years 1988 and 1991 (periods before and after regulations went into law) were included in the analysis. Patients from nonteaching hospitals served as controls.

The authors of the current analysis of Medicare patients in JAMA studied the association between changes in the ACGME work hours rules and mortality rates in Medicare patients hospitalized in short-term, acute-care US non-government hospitals and compared trends in risk adjusted mortality rates between teaching-intense hospitals compared to less teaching-intense hospitals to examine whether mortality changed after implementation of the rules in 2003. The main outcome measure was death within 30 days of hospital admission for all patients admitted for stroke, AMI, gastrointestinal bleeding, CHF, general surgery, orthopedic surgery, or vascular surgery. The period of assessment was from July 1, 2000, to June 30, 2005. Excluded from the analysis were patients younger than 66 and those older than 90 years of age.

Only the first admission in the 5-year period was considered. Patients from hospitals that opened or closed during the assessment period were not included. The final sample for analysis included 8,529,595 patients from 3321 hospitals.

The level of teaching intensity was described as the resident-to-bed ration, and was calculated as the number of interns and residents divided by the number of operational beds. 14% of patients were from “major or very major teaching hospitals.” The number of admissions for each of the conditions assessed differed by < 10% per year.

Between years 2 and 1 pre-reforms, the unadjusted mortality rates for the combined medical group increased in the very major teaching intensive hospitals more than in the other hospitals. Yet, mortality subsequently changed at similar rates post reform from years 1 to 2. The authors found that in the 3 years pre-reforms, stroke mortality had diverged significantly in more compared to less teaching-intensive hospitals (p= 0.003), and thus separate post hoc analyses were conducted to examine the associations without stroke. Except for stroke, there was no significant change in the odds of mortality in less compared to more teaching intensive hospitals in either post reform years 1 or 2.

The authors conclude that the results of their analysis suggest that after 2 years of work hour reforms, there is neither a significant positive nor negative change in mortality among Medicare patients with the conditions analyzed. Several limitations to this study are described including that mortality was the chosen outcomes. The work hours changes were implemented to reduce deaths from medical errors, and thus measurement of other outcomes such as patient safety indicators may assist in explaining the relative effects of decreased continuity of care compared with decreased resident fatigue. Additionally, the study does not include data on the actual number of hours worked at each hospital.

Other studies have also assessed the impact of the ACGME rules. A study using the Healthcare Cost and Utilization Project’s Nationwide Inpatient Sample [5] found a small statistically significant relative improvement in mortality outcomes for medical but not surgical patients in teaching compared to nonteaching hospitals following the implementation of ACGME rules. This study included only 551 hospitals and did not distinguish between a single admission from multiple patients or multiple admissions from a single patient. The authors, Shetty and Bhattacharya, used in-hospital mortality as the primary outcome in 20 medical and 15 surgical diagnoses.

Another, single hospital study [6] found no changes in length of stay, readmission rates at 30-days, or in adverse drug-to-drug interactions. The study was conducted in urban, academic medical center. This was a retrospective cohort study of 14,260 consecutive patients discharged from the teaching (housestaff) service and 6664 consecutive patients discharged from the nonteaching (hospitalist) service between July 1, 2002, and June 30, 2004. The study was not powered to compare changes in mortality. Dr. Harlan Krumholz, Harold H. Hines, Jr. Professor of Medicine and Epidemiology and Public Health (Cardiology), Yale University, and an author of the single hospital study, commented for WikiDoc, “Our research took advantage of the fact that in our hospital some of the medicine patients received care by housestaff and others by hospitalists. As a result we were able to look at changes in care and outcomes over time in both groups, a techniques called difference in differences, and determine if the introduction of work hours was associated with changes that were not reflected by the hospitalists, who were not affected by the new regulations. Our findings suggested a benefit associated with the introduction of the work hours–and indicated a very low likelihood that harm had occurred.”

A third study, also reported in the September 5 issue of JAMA, assessed the population of patients receiving care in 131 Veterans Administration health care system hospitals [7]. In total, the VA system is the largest aggregate of residency trainees in the US. The VA study found improved mortality for medical patients in post reform year 2 at more teaching intensive environments; however, for surgical patients there were no differences between more or less teaching intensive hospitals.

In conclusion, the authors of the Medicare study suggest that there is a need for research to examine different approaches to work hours both with respect to design and intensity of work and the assessment of “clinically relevant patient outcomes in addition to mortality.”

References


 * 1) ref1 pmid=12683483
 * 2) ref2 pmid=9231952
 * 3) ref3 pmid=17785642
 * 4) ref4 pmid=14748854
 * 5) ref5 pmid=17548403
 * 6) ref6 pmid=17548401
 * 7) ref7 pmid=17785643