Morbidity, mortality, and health care costs for patients undergoing spine surgery following the ACGME resident duty-hour reform: Clinical article

Abstract

Object: The Accreditation Council for Graduate Medical Education (ACGME) implemented resident duty-hour restrictions on July 1, 2003, in concern for patient and resident safety. Whereas studies have shown that duty-hour restrictions have increased resident quality of life, there have been mixed results with respect to patient outcomes. In this study, the authors have evaluated the effect of duty-hour restrictions on morbidity, mortality, length of stay (LOS), and charges in patients who underwent spine surgery.

Methods: The Nationwide Inpatient Sample was used to evaluate the effect of duty-hour restrictions on complications, mortality, LOS, and charges by comparing the prereform (2000-2002) and postreform (2005-2008) periods. Outcomes were compared between nonteaching and teaching hospitals using a difference-in-differences (DID) method. Results A total of 693,058 patients were included in the study. The overall complication rate was 8.6%, with patients in the postreform era having a significantly higher rate than those in the pre-duty-hour restriction era (8.7% vs. 8.4%, p < 0.0001). Examination of hospital teaching status revealed complication rates to decrease in nonteaching hospitals (8.2% vs. 7.6%, p < 0.0001) while increasing in teaching institutions (8.6% vs. 9.6%, p < 0.0001) in the duty-hour reform era. The DID analysis to compare the magnitude in change between teaching and nonteaching institutions revealed that teaching institutions to had a significantly greater increase in complications during the postreform era (p = 0.0002). The overall mortality rate was 0.37%, with no significant difference between the pre- and post-duty-hour eras (0.39% vs. 0.36%, p = 0.12). However, the mortality rate significantly decreased in nonteaching hospitals in the postreform era (0.30% vs. 0.23%, p = 0.0008), while remaining the same in teaching institutions (0.46% vs. 0.46%, p = 0.75). The DID analysis to compare the changes in mortality between groups revealed that the difference between the effects approached significance (p = 0.069). The mean LOS for all patients was 4.2 days, with hospital stay decreasing in nonteaching hospitals (3.7 vs. 3.5 days, p < 0.0001) while significantly increasing in teaching institutions (4.7 vs. 4.8 days, p < 0.0001). The DID analysis did not demonstrate the magnitude of change for each group to differ significantly (p = 0.26). Total patient charges were seen to rise significantly in the post-duty-hour reform era, increasing from $40,000 in the prereform era to $69,000 in the postreform era. The DID analysis did not reveal a significant difference between the changes in charges between teaching and nonteaching hospitals (p = 0.55).

Conclusions: The implementation of duty-hour restrictions was associated with an increased risk of postoperative complications for patients undergoing spine surgery. Therefore, contrary to its intended purpose, duty-hour reform may have resulted in worse patient outcomes. Additional studies are needed to evaluate strategies to mitigate these effects and assist in the development of future health care policy.

Keywords: ACGME = Accreditation Council for Graduate Medical Education; CCI = Charlson Comorbidity Index; DID = difference-in-differences; ICD-9-CM = International Classification of Diseases, Ninth Revision, Clinical Modification; LOS = length of stay; MI = myocardial infarction; NIS = Nationwide Inpatient Sample; complications; duty-hour restriction; mortality; outcome; resident.