Evidence Hub

Anticoagulation-related outcomes in patients receiving warfarin after starting levofloxacin or gatifloxacin

Mathews S, Cole J, Ryono RA

Pharmacotherapy, 2006

92 participants

Abstract

STUDY OBJECTIVE: To compare anticoagulation-related outcomes in patients receiving stable dosages of warfarin who started levofloxacin or gatifloxacin therapy.

DESIGN: Retrospective medical record review.

SETTING: Veterans Affairs medical center.

PATIENTS: Of 92 patients receiving the same dosages of warfarin for at least 4 weeks before starting antibiotic therapy, 54 received levofloxacin between January and September 2003, and 38 received gatifloxacin between January and September 2004.

MEASUREMENTS AND MAIN RESULTS: Data were obtained through the hospital's pharmacy, laboratory, and general patient databases and through electronic medical records. The INRs evaluated were prefluoroquinolone use, defined as the last INR measured before the start of antibiotic therapy (up to 4 wks earlier), and postfluoroquinolone use, defined as any INR measured during antibiotic therapy through 1 week after discontinuation of the antibiotic. Analyzed outcomes included the percentage of patients with postfluoroquinolone INRs that were above 4, that exceeded the therapeutic goal, or that exceeded the goal by more than 1 point; INR changes of more than 0.5, 1, or 1.5 points above the INR before fluoroquinolone use; major or minor bleeding events; requirement for vitamin K administration; warfarin dosage reduction or withholding doses; and warfarin-related hospital, emergency, or urgent care admissions or visits. No significant differences were noted in baseline characteristics with regard to…

How strong is the evidence?

Evidence Hub reads this as a cohort study, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence. Reported size: 92 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free