Mortality Among Older Adults Before Versus After Hospital Transition to Intensivist Staffing.

BACKGROUND: A large body of research suggests that hospitals with intensive care units staffed by board-certified intensivists have lower mortality rates than those that do not.

OBJECTIVE: To determine whether hospitals can reduce their mortality by adopting an intensivist staffing model.

DESIGN: Retrospective, longitudinal study using 2003-2010 Medicare data and the Leapfrog Group Hospital surveys.

SETTING AND PATIENTS: In total, 2,916,801 Medicare patients at 488 US hospitals.

MEASUREMENTS: We studied 30-day and in-hospital mortality among patients with several common medical and surgical conditions. We first compared risk-adjusted mortality rates of 3 groups of hospitals: those that were intensivist staffed throughout this time period, those that were not intensivist staffed, and those that transitioned to intensivist staffing somewhere during the period. We then examined rates of mortality improvement within each of the 3 groups and used difference-in-differences techniques to assess the independent effect of intensivist staffing among the subset of hospitals that transitioned.

RESULTS: Hospitals with intensivist staffing at the beginning of our study period had lower mortality rates than those without. However, hospitals that adopted intensivist staffing during the study period did not substantially improve their mortality rates. In our difference-in-differences analysis, there was no significant independent improvement in mortality after transitioning to intensivist staffing either overall [relative risk (RR), 0.96; 95% confidence interval (CI), 0.90-1.02] or in the medical (RR, 0.95; 95% CI, 0.89-1.02) or surgical populations (RR, 0.97; 95% CI, 0.84-1.10).

LIMITATIONS: Risk adjustment was based on administrative data. Categorization of exposure was by survey response at the hospital level.

CONCLUSIONS: Adoption of an intensivist staffing model was not associated with improved mortality in Medicare beneficiaries. These findings suggest that the lower mortality rates previously observed at hospitals with intensivist staffing may be attributable to other factors.