Anti-MRSA Therapy Associated with Greater 30-day Mortality Compared with Standard Therapy for Veterans with Pneumonia
Pneumonia is the leading cause of death from infection in the United States, and timely empirical antibiotic therapy against the most likely pathogens is a cornerstone of care. However, causative pathogens are rarely identified, leaving uncertainty in the choice of antibiotic therapy. For patients hospitalized for community-onset pneumonia, this uncertainty has been magnified by the emergence of resistant organisms, such as methicillin-resistant Staphylococcus aureus (MRSA). This retrospective cohort study sought to determine the association of empirical anti-MRSA therapy with 30-day mortality for patients hospitalized with pneumonia. Investigators used existing data for all VA hospitalizations for community-onset pneumonia from January 2008 to December 2013 (n=88,605). Patients were excluded if they were not given an antimicrobial within the first day of hospitalization, were hospitalized for pneumonia in the previous month, or were transferred from another acute care facility. The primary study outcome was all-cause mortality within 30 days of hospitalization. Investigators also examined patient demographics, comorbidities (i.e., age, congestive heart failure, renal disease, residence at a nursing home), as well as clinical risk factors for resistant organisms.
- Empirical anti-MRSA therapy was significantly associated with greater 30-day mortality compared with standard therapy alone.
- There was a significant increase in 30-day mortality associated with empirical anti-MRSA therapy plus standard therapy, compared with standard therapy alone, among patients admitted to the intensive care unit (ICU) and those with a high clinical risk for MRSA. Thus, investigators could establish no benefit of empirical anti-MRSA therapy, even when risk factors for MRSA were present or clinical severity warranted admission to the ICU.
- The use of anti-MRSA therapy also was associated with increased risk of kidney injury and secondary infections.
- These results contribute to a growing body of evidence that questions the value of the empirical use of anti-MRSA therapy using existing risk approaches.
- This study relied on diagnosis codes assigned at the end of hospitalization, which might have included some patients who did not initially receive a diagnosis of pneumonia.
This study was partly funded by HSR&D. Drs. Jones, Stevens, Nelson, Sauer, Yarbrough, and Samore (Director) are part of HSR&D’s Informatics, Decision-Enhancement and Analytic Sciences (IDEAS) Center, Salt Lake City, UT. Dr. Goetz is with HSR&D’s Center for the Study of Healthcare Innovation, Implementation and Policy (CSHIPP), Los Angeles, CA.
Jones B, Ying J, Stevens V, Haroldsen C, He T, Nevers M, Christensen M, Nelson R, Stoddard G, Sauer B, Yarbrough P, Jones M, Goetz M, Greene T, and Samore M. Empirical Anti-MRSA vs Standard Antibiotic Therapy and Risk of 30-Day Mortality in Patients Hospitalized for Pneumonia. JAMA Internal Medicine. February 17, 2020; Epub ahead of print.