Association Between Initial Route of Fluoroquinolone Administration and Outcomes in Patients Hospitalized for Community-acquired Pneumonia

Background. Fluoroquinolones have equivalent oral and intravenous bioavailability, but hospitalized patients with community-acquired pneumonia (CAP) generally are treated intravenously. Our objectives were to compare outcomes of hospitalized CAP patients initially receiving intravenous vs oral respiratory fluoroquinolones. Methods. This was a retrospective cohort study utilizing data from 340 hospitals involving CAP patients admitted to a non-intensive care unit (ICU) setting from 2007 to 2010, who received intravenous or oral levofloxacin or moxifloxacin. The primary outcome was in-hospital mortality. Secondary outcomes included clinical deterioration (transfer to ICU, initiation of vasopressors, or invasive mechanical ventilation [IMV] initiated after the second hospital day), antibiotic escalation, length of stay (LOS), and cost. Results. Of 36 405 patients who met inclusion criteria, 34 200 (94%) initially received intravenous treatment and 2205 (6%) received oral treatment. Patients who received oral fluoroquinolones had lower unadjusted mortality (1.4% vs 2.5%; P=.002), and shorter mean LOS (5.0 vs 5.3; P<.001). Multivariable models using stabilized inverse propensity treatment weighting revealed lower rates of antibiotic escalation for oral vs intravenous therapy (odds ratio [OR], 0.84; 95% confidence interval [CI], .74-.96) but no differences in hospital mortality (OR, 0.82; 95% CI, .58-1.15), LOS (difference in days 0.03; 95% CI, -.09-.15), cost (difference in $-7.7; 95% CI, -197.4-182.0), late ICU admission (OR, 1.04; 95% CI, .80-1.36), late IMV (OR, 1.17; 95% CI, .87-1.56), or late vasopressor use (OR, 0.94; 95% CI, .68-1.30). Conclusions. Among hospitalized patients who received fluoroquinolones for CAP, there was no association between initial route of administration and outcomes. More patients may be treated orally without worsening outcomes.