431. An Estimate of Inappropriate Antibiotic Prescribing Rates for Outpatient Uncomplicated Urinary Tract Infections.
Session: Poster Abstract Session: HAI: Epidemiologic Methods
Thursday, October 5, 2017
Room: Poster Hall CD


The CDC estimates that at least 30% of outpatient antibiotics are inappropriate. However, detailed national estimates of antibiotic appropriateness based on drug, dose, and duration for many outpatient conditions remain lacking. The aim of this study was to evaluate the appropriateness of antibiotic prescriptions for uncomplicated urinary tract infections (UTI) based on dose and assess the impact of national best practice guidelines on antibiotic selection.


We analyzed outpatient claims data for non-pregnant women aged 18- 44 years from 2009-2013 using the Truven Health Analytics MarketScan Commercial Claims database. Uncomplicated UTIs (based on ICD-9-CM diagnosis codes) were identified per Infectious Diseases Society of America (IDSA) Guidelines. We examined treatment appropriateness by comparing antibiotic class and duration to IDSA guidelines. One month after the IDSA guideline publication date defined the “start” of the post-guideline period. Statistical testing was performed via Chi-square tests.


702,616 women were identified with an index uncomplicated UTI. Prescription of a first-line therapy agent increased after the release of the guidelines from 48.6% to 50.5% (Figure 1a; Risk Difference (RD)=1.9%; Risk Ratio (RR)=0.96; 95% Confidence Interval (CI)= 0.96-0.97; p<0.001).  Inappropriate duration of antibiotic decreased from 63.3% to 60.4% (Figure 1b; RD= 3.1%; RR= 0.94; 95% CI=0.93-0.94; p<0.001).  When assessing both first-line therapy and antibiotic duration, inappropriate antibiotic prescribing decreased from 76.4% to 72.8% (Figure 1c; RD=4.7%; RR=0.90; 95% CI=0.90-0.91) after publication of the IDSA guideline.


In this privately insured cohort, inappropriate antibiotic prescribing for uncomplicated UTIs was much higher than previously reported estimates. Best-practice guidelines regarding antibiotic prescribing were associated with statistically significant, but unlikely clinically significant improvements in first-line antibiotic selection and duration. Further research is needed to identify interventions to improve outpatient antibiotic prescribing in the future.


Michael J Durkin, MD MPH1,2, Matthew Keller, MA1, Jennie H. Kwon, DO, MSCI3, Erik R. Dubberke, MD, MSPH, FIDSA, FSHEA4 and Margaret a. Olsen, PhD, MPH3, (1)Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, (2)Washington University Institute for Public Health, St. Louis, MO, (3)Infectious Diseases, Washington University School of Medicine, St. Louis, MO, (4)Washington University School of Medicine, St. Louis, MO


M. J. Durkin, None

M. Keller, None

J. H. Kwon, None

E. R. Dubberke, None

M. A. Olsen, None

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