138. An Antimicrobial Prescription Optimization System Improves the Adequacy of Antibacterial Dosage in Obese Inpatients
Session: Poster Abstract Session: Antimicrobial Stewardship: Adverse Drug Events
Thursday, October 8, 2015
Room: Poster Hall
Posters
  • IDWEEK S Sirard.pdf (4.7 MB)
  • Background: Obesity affects the pharmacokinetics of antibacterials (Abx). As a consequence, Abx are frequently underdosed in obese patients which may increase the risk of unfavorable outcomes. Antimicrobial stewardship programs can improve the use of Abx in obese inpatients. The aim of this study was to analyze the impact of an antimicrobial stewardship intervention on Abx optimal dosing in obese inpatients.

    Methods: This study included all hospitalized adults receiving selected Abx in a 677-bed hospital in Quebec, Canada between 08/2008 and 08/2013. Data were retrospectively collected from Antimicrobial Prescription Surveillance System (APSS), a computerized decision support system. We evaluated the number of inappropriate days of Abx treatment per 1000 hospitalized-patients days and the proportion of inappropriate days of Abx treatment per total days of Abx treatment. Pre-intervention rates (2008-10) were compared to post-intervention rates (2010-13) in non-obese (BMI<30), obese (30≤BMI<39.9), and morbidly obese (MO) (BMI≥40) patients.

    Results: A total of 40 605 hospitalizations with Abx were included in the study: 78% (31 614) concerned non-obese patients, 16% (6481) obese patients, and 6% (2510) MO patients.

    Mean percentage of days of inappropriate treatment (dose and frequency) according to BMI and Abx classes, before and after the implementation of APSS

    BMI < 30 kg/m2

     

    30≤BMI<39.9 kg/m2

     

    BMI ≥ 40 kg/m2

    Pre-intervention mean (%)

    Post-intervention mean (%)

    Difference

     

    Pre-intervention mean (%)

    Post-intervention mean (%)

    Difference

     

    Pre-intervention mean (%)

    Post-intervention mean (%)

    Difference

    Aminoglycosides

    53.9

    41.7

    -12.2 *

     

    38.9

    52.0

    13.1 *

     

    28.6

    23.2

    -5.4

    Penicillins †

    14.5

    12.8

    -1.7 *

     

    17.1

    14.0

    -3.2 *

     

    25.1

    13.6

    -11.5 *

    Carbapenems

    33.5

    43.0

    9.5 *

     

    23.6

    34.1

    10.6 *

     

    54.6

    62.2

    7.7

    Cephalosporins

    8.5

    5.6

    -2.9 *

     

    13.0

    11.8

    -1.2

     

    79.2

    81.7

    2.6 *

    Fluoroquinolones

    9.6

    8.1

    -1.5 *

     

    13.8

    7.1

    -6.8

     

    55.0

    34.3

    -20.7 *

    *Significant difference in mean percentage (chi-square; p<0.05)

    † Including β-lactamase inhibitors

    Conclusion: Regardless of the weight of patients, APSS had a positive impact on dosing optimization on several classes of Abx. In MO patients, the effect was the most important on penicillins with or without β-lactamase inhibitor and fluoroquinolones. Improving Abx prescriptions in MO patients is important since suboptimal dosing could be associated with unfavorable outcomes.

    Stephanie Sirard, M.Sc.1, Vincent Nault, M.Sc.1, Marie-France Langlois, MD2, Julie Perron, B.Pharm., M.Sc.3 and Louis Valiquette, MD, MSc1, (1)Microbiology and Infectious Diseases, Université de Sherbrooke, Sherbrooke, QC, Canada, (2)Department of Medicine, Division of Endocrinology, Université de Sherbrooke, Sherbrooke, QC, Canada, (3)Department of Pharmacy, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada

    Disclosures:

    S. Sirard, None

    V. Nault, Lumed inc: Shareholder , Salary

    M. F. Langlois, None

    J. Perron, None

    L. Valiquette, Lumed Inc.: Shareholder , Licensing agreement or royalty

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 7th with the exception of research findings presented at the IDWeek press conferences.