Successful Decrease in Therapy Duration for Community-Acquired Pneumonia

Abstract & Commentary

By Richard R. Watkins, MD, MS, FACP, Division of Infectious Diseases, Akron General Medical Center, Akron, OH; Associate Professor of Internal Medicine, Northeast Ohio Medical University, Rootstown, OH. Dr. Watkins reports no financial relationships in this field of study.

This article originally appeared in the December 2012 issue of Infectious Disease Alert. It was edited by Stan Deresinski, MD, FACP, FIDSA, and peer reviewed by Timothy Jenkins, MD. Dr. Deresinski is Clinical Professor of Medicine, Stanford University, and Dr. Jenkins is Assistant Professor of Medicine, University of Colorado, Denver Health Medical Center. Dr. Deresinski does research for the National Institutes of Health, and is an advisory board member and consultant for Merck, and Dr. Jenkins reports no financial relationships relevant to this field of study.

Synopsis: In this single-center, prospective study, median duration of antibiotics for community-acquired pneumonia (CAP) decreased from 10 to 7 days with an antibiotic stewardship program that included education and prospective feedback to the managing team.

Source: Avdic E, et al. Impact of an antimicrobial stewardship intervention on shortening the duration of therapy for community-acquired pneumonia. Clin Infect Dis 2012;54:1581-1587.

One of the unintended consequences of the Centers for Medicare & Medicaid Services (CMS) performance measures for CAP was that clinicians often started antibiotics too quickly in patients without infection. Subsequently, the requirement that antibiotics be initiated within 6 hours of patient presentation was retired as of Jan. 1, 2012. Another concern has been that antibiotics are continued longer than necessary. The Infectious Diseases Society of America/American Thoracic Society guidelines on CAP note that available data on short-course treatment (i.e. 5 to 7 days) do not suggest any difference in outcome compared to longer courses.1 Overuse of antibiotics can lead to deleterious effects, including drug toxicities and Clostridium difficile infection (CDI).

Avdic and colleagues sought to determine if certain outcomes in CAP (decreasing duration of treatment, increasing use of microbiology to narrow therapy, and decreasing duplicate therapy within 24 hours, such as receiving two doses of a respiratory fluoroquinolone) could be improved. They conducted a single-center, prospective, pre- and post-intervention study that included all adult patients admitted to an inpatient medical service between two distinct time periods, January 1st to March 31st 2008 and February 1st to May 10, 2010. Those excluded were (1) residents of extended care facilities; (2) patients diagnosed with cystic fibrosis; (3) patients admitted to the oncology service; and (4) patients admitted for pneumonia in the preceding 30 days. After the initial observation period in 2008, a three-part intervention to improve management of CAP was undertaken. It consisted of a survey of the medical staff to assess their knowledge regarding management of CAP; an educational lecture presented to the staff that included survey results and evidence-based information about duration of therapy; and a prospective review of the management of patients with CAP by the antibiotic stewardship pharmacy specialists with oral feedback regarding suggested changes. The primary outcome measured was duration of antibiotic therapy. Secondary outcomes were percentage of cases where microbiology data was used to narrow therapy and percentage of patients receiving duplicate therapy.

Sixty-two patients were included in the pre-intervention period, and sixty-five in the intervention period. Patient characteristics were similar during both time frames, although there were more patients with alcohol abuse in the pre-intervention period. The median pneumonia score index (PSI) was 82 in both periods. Forty-eight stewardship interventions were made in 34 patients during the intervention period, and 69% of them were accepted by the managing team. In 2008, 21 patients (34%) had a causative organism identified, compared to 9 (14%) in 2010. This led to a change in therapy based on susceptibility testing in 3 of 16 cases (19%) in 2008 and 4 of 6 cases (67%) in 2010. Patients in the intervention group were more likely to be discharged home without antibiotics compared to the pre-intervention group (26% vs. 14%, respectively). More patients were discharged home with a respiratory quinolone in 2008 (63%) than in 2010 (35%). Furthermore, fewer patients in the intervention period received duplicate therapy within 24 hours in the intervention group (90% in 2008 vs. 55% in 2010). The median duration of therapy was decreased in the intervention group from 10 to 7 days (P < .001), and the most frequent duration was 8 to 10 days in the pre-intervention period and 6 to 7 days in the intervention period. There was a similar length of stay between both groups (4 days in 2008 and 5 days in 2010). Of note, the 30-day readmission rate was higher in the pre-intervention period (9 [14%] in 2008 vs. 5 [8%] in 2010). Finally, 3 patients in the pre-intervention and 1 in the intervention group developed CDI.

Commentary

Previous research has shown that decreasing the length of antibiotic therapy can slow development of resistance in respiratory pathogens.2 In the present study, sputum cultures were rarely collected in the emergency department, and most patients received at least one dose of an antibiotic before one was obtained. This was unfortunate since negative or nondiagnostic sputum cultures often led to unnecessarily broad spectrum antibiotic therapy for longer than was clinically needed. The narrowing of antibiotics in patients with positive culture results increased by 47% in the intervention group. This finding along with shortening antibiotic duration has the potential to both decrease the emergence of resistance and minimize antibiotic adverse events.

The study was limited in several ways. First, it was conducted at a single center and had a small number of patients. Second, patients might not have taken the antibiotics they were prescribed at discharge, which could have impacted the 30-day readmission rate. Third, the intervention period occurred shortly after the H1N1 influenza pandemic, which could have affected the rates of admission for CAP, severity of illness, type of bacterial pathogens, and the practice behaviors of the physicians. Finally, the institution had an experienced antibiotic stewardship program so the results might not be generalizable to other institutions. Although the authors comment on the rates of CDI in the pre- and intervention periods, the small number of patients (3 and 1, respectively) do not allow for the assumption of causality.

In conclusion, this study demonstrates that it is possible for antibiotic stewardship interventions to make a notable impact on the treatment of CAP. Future guidelines on CAP should continue to emphasize shorter treatment courses to minimize the ongoing threat of antibiotic resistance.

References

1. Mandell LA, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis 2007;44(Suppl 2):S27-72.

2. Albrich WC, et al. Antibiotic selection pressure and resistance in Streptococcus pneumoniae and Streptococcus pyogenes. Emerg Infect Dis 2004;10:514-517.