Levels of nurse staffing and burnout were significantly associated with rates of hospital-acquired infections in Pennsylvania, researchers said.
For each patient added to a nurse's workload, the risk of urinary tract infections rose by 0.86 per 1,000 (P=0.02) and by 0.93 per 1,000 for surgical site infections (P=0.04), according to Jeannie P. Cimiotti, DNSc, RN, of Rutgers University College of Nursing, and colleagues.
In addition, each 10% increase in the proportion of nurses with high scores on a standard measure of burnout was associated with increases of 0.85 per 1,000 in urinary tract infections (P=0.02) and 1.58 per 1,000 in surgical site infections (P<0.01), the researchers reported in the American Journal of Infection Control.
However, a statistical analysis that adjusted for nurse burnout showed that the association between nurse staffing and infection rates was attenuated. That led Cimiotti and colleagues to conclude that burnout was the key factor.
"Based on our finding that the staffing-infection relationship is mediated by job-related burnout, practitioners should work to implement organizational changes known to build job engagement, such as educational interventions, performance feedback, and social support, as strategies to reduce nurse burnout and thereby help control infections in acute care facilities," Cimiotti and colleagues wrote.
Numerous earlier studies had found associations between nurse staffing levels and hospital infection rates, but the factors mediating that relationship have remained murky, the researchers indicated.
Because job-related stress and decreased morale in nurses have been shown to affect patient care, Cimiotti and colleagues sought to examine it as a driver of hospital-acquired infections.
They relied on three data sources: a 2006 survey of some 7,000 nurses in Pennsylvania that included questions about burnout-related issues, Pennsylvania state data on healthcare-acquired infections in 161 hospitals that year, and hospital characteristics compiled annually by the American Hospital Association.
Nurse burnout was specifically assessed with the Maslach Burnout Inventory-Human Services Survey, a 22-item instrument covering emotional exhaustion, depersonalization, and personal accomplishment. For purposes of the current study, Cimiotti and colleagues used only the emotional exhaustion subscale, setting a score of 27 as the threshold for burnout.
"Overall, 16 patients per 1,000 acquired some type of infection while hospitalized," Cimiotti and colleagues reported
They found that catheter-associated urinary tract infections (8.6 per 1,000) and surgical site infections (4.2 per 1,000) were the most common and focused on them for their detailed analyses.
These included adjustments for hospital factors including size and teaching status.
After quantifying the associations between infection rates and nurse staffing and burnout, the researchers then estimated the cost savings that would accrue if nurse burnout were reduced - assuming, that is, that burnout is indeed a causative factor in hospital-acquired infections.
Using CDC data on the direct costs of treating infections, Cimiotti and colleagues found that a 10% reduction in the number of nurses with high burnout would have prevented 1,335 urinary tract infections and saved about $1 million in the 161 Pennsylvania hospitals. The same 10% reduction in burnout would have prevented 744 surgical site infections and - because such infections are more difficult to treat - could have saved from $8 million to $22 million dollars.
Primary source: American Journal of Infection Control