Do limited resident work hours affect mortality rates?

A study in Annals of Internal Medicine (7/17/2007) suggests it does, at least in certain populations. The study looked at a nationally representative sample of hospital patients between 2001 and 2004 to determine whether regulations that limit resident workweeks changed mortality rates in hospitalized patients.

Despite concerns that limited resident workweeks would worsen patient outcomes, the researchers concluded that "these regulations correlated with a 0.25% decrease in mortality and a relative risk reduction of 3.75% for internal medicine patients in teaching hospitals." However, no such correlation was found for surgical patients and improved outcomes.

These findings contrast with previous studies- including those in obstetric, gynecologic, and perinatal care settings-that found no evidence of a correlation between improved outcomes and work-hour restrictions. Still, the researchers note that their study used data involving 1.5 million adult patients from 551 US community hospitals-a much larger population than that of the previous studies.