High inpatient occupancy levels associated with lower risk of hospital-acquired C. diff

Researchers analyzed administrative data from 2008 to 2012 among Medicare recipients with a discharge diagnosis of acute myocardial infarction, heart failure, or pneumonia at 327 California hospitals.


Patients admitted on a day with high levels of hospital occupancy have a lower likelihood of hospital-acquired Clostridium difficile infection than those admitted on a day with low or intermediate occupancy levels, according to a new study.

Researchers analyzed administrative data from 2008 to 2012 among Medicare recipients with a discharge diagnosis of acute myocardial infarction, heart failure, or pneumonia at 327 California hospitals. Using daily census data, they estimated the relationship between hospital occupancy during hospitalization (range, 0 to 1; four groups) and hospital-acquired C. difficile infection. Results were published online on June 27 by the Journal of Hospital Medicine.

A total of 558,344 discharges were included in the analysis. Higher admission-day occupancy was associated with significantly lower adjusted odds of C. difficile infection. Compared to the 0 to 0.25 occupancy group, patients admitted on a day of 0.51 to 0.75 occupancy had 0.86 odds of C. difficile infection (95% CI, 0.75 to 0.98), and those admitted on a day of 0.76 to 1.00 occupancy had 0.87 odds of C. difficile infection (95% CI, 0.75 to 1.01).

Over the course of hospitalization, groups with intermediate levels of average occupancy had more than a threefold increased adjusted odds of C. difficile infection compared to the 0 to 0.25 occupancy group (odds ratios, 3.04 [95% CI, 2.33 to 3.96] for the 0.26 to 0.50 group and 3.28 [95% CI, 2.51 to 4.28] for the 0.51 to 0.75 group). The high occupancy group, however, did not have significantly different odds of C. difficile infection relative to the low occupancy group (odds ratio, 0.96; 95% CI, 0.70 to 1.31).

The inverse relationship between C. difficile infection and admission occupancy was contrary to the authors' expectations. “These findings suggest that an exploration of the processes associated with hospitals accommodating higher occupancy might elucidate measures to reduce [C. difficile infection],” they said, noting variations in staffing, policies, practices, and procedures during different stages of occupancy.

The authors noted limitations of the study, such as its focus on one state and potential inaccuracies in coding and data. “These findings should prompt exploration of how hospitals react to occupancy changes and how those care processes translate into [hospital-acquired conditions] in order to inform best practices for hospital care,” they wrote.