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Changes in outcomes for internal medicine inpatients after work-hour regulations
Leora I Horwitz1, Mikhail Kosiborod, Zhenqiu Lin
1Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, and Yale University School of Medicine, New Haven, Connecticut 06520-8088, USA. leora.horwitz@yale.edu
Background:
Limits on resident work hours are intended to reduce fatigue-related errors, but may raise risk by increasing transfers of responsibility for patients.
Objective:
To examine changes in outcomes for internal medicine patients after the implementation of work-hour regulations.
Design:
Retrospective cohort study.
Setting:
Urban, academic medical center.
Patients:
14,260 consecutive patients discharged from the teaching (housestaff) service and 6664 consecutive patients discharged from the nonteaching (hospitalist) service between 1 July 2002 and 30 June 2004.
Measurements:
Outcomes included intensive care unit utilization, length of stay, discharge disposition, 30-day readmission rate to the study institution, pharmacist interventions to prevent error, drug-drug interactions and in-hospital death.
Results:
The teaching service had net improvements in 3 outcomes. Relative to changes experienced by the nonteaching service, the rate of intensive care unit utilization decreased by 2.1% (95% CI, -3.3% to -0.7%; P = 0.002), the rate of discharge to home or rehabilitation facility versus elsewhere improved by 5.3% (CI, 2.6% to 7.6%; P < 0.001), and pharmacist interventions to prevent error were reduced by 1.92 interventions per 100 patient-days (CI, -2.74 to -1.03 interventions per 100 patient-days; P < 0.001). Teaching and nonteaching services had similar changes over time in length of stay, 30-day readmission rate, and adverse drug-drug interactions. In-hospital death was uncommon in both groups, and change over time was similar in the 2 groups.
Limitations:
The study was a retrospective, nonrandomized design that assessed a limited number of outcomes. Teaching and nonteaching cohorts may not have been affected similarly by secular trends in patient care.
Conclusions:
After the implementation of work-hour regulations, 3 of 7 outcomes improved for patients in the teaching service relative to those in the nonteaching service. The authors found no evidence of adverse unintended consequences after the institution of work-hour regulations.
