3092 — Acceptable Failure Rates for Therapy of Complicated Urinary Tract Infection (UTI) in Older Men: Implications for Antibiotic Therapy and Resistance

Perencevich EN (VA Maryland Healthcare System), McGregor JC (Oregon State University), Harris AD (VA Maryland Healthcare System), Bradham DD (VA Maryland Healthcare System)

Objectives:
Decreasing the duration of antibiotic therapy is an attractive strategy for delaying emergence of antimicrobial resistance. However, reduced therapy durations are typically associated with increases in treatment failure rates. The paucity of data about optimal treatment durations and corresponding failure rates encourages over treatment by risk-averse physicians. This may be particularly true in complicated UTIs, a frequent condition among US Veterans that is typically treated with oral fluoroquinolones. Using a case scenario, this study utilized a decision analysis technique known as contingent valuation analysis to identify treatment failure rates that would be acceptable to treating physicians. We aimed to quantify the acceptable failure rates for standard therapy of complicated UTIs in physicians enrolling patients in a clinical trial.

Methods:
The authors developed a case scenario for a representative 60-year old male patient who developed a complicated UTI. The patient received standard therapy including a course of oral antibiotic therapy. The case description and a questionnaire were distributed to 88 physicians involved in a multicenter randomized trial comparing the efficacy of 2 oral antibiotics for complicated UTI. Each physician was given one of 10 failure rates, ranging from 1% to 50%, and asked if they would accept or reject the given value. The authors used logistic regression analysis to evaluate the relationship between specific failure rates offered to physicians and their willingness to accept them.

Results:
Overall, 86 physicians (98%) returned the questionnaire. Mean years in practice was 16.6 years. Logistic regression analysis determined that the median acceptable failure rate was 16.7%. 75% found a failure rate of 5.4% acceptable and 25% found a failure rate as high as 28% acceptable. Adjusting for years in practice did not alter these results.

Implications:
Physicians varied considerably in the level of treatment failure they found to be acceptable. Quantifying the failure rates for oral therapy of complicated UTIs might assist in selecting an optimal treatment duration.

Impacts:
Contingent valuation is useful in delineating acceptable treatment failure thresholds, which is a first step in reducing durations of antimicrobial therapy and slowing the emergence of antibiotic resistance among US veterans.