Short-course superior to long-course antibiotic therapy for cIAIs
Patients with complicated intra-abdominal infections were more likely to have desirable outcomes if they received antibiotics for a shorter duration, according to recent findings from the STOP-IT trial.
Arthur R. Celestin, MD, of the department of surgery at Beth Israel Deaconess Medical Center, and colleagues used a novel method combining two measures of clinical outcomes — desirability of outcome ranking (DOOR) and response adjusted for duration of antibiotic risk (RADAR) — to assess 518 patients with complicated intra-abdominal infections (cIAIs) who were randomly assigned to receive short-course antibiotic therapy or a traditional duration of therapy.
“The concept of DOOR is to rank all trial participants with ordinal clinical outcomes that include benefits, harms, and quality of life,” the researchers wrote in Clinical Infectious Diseases. “RADAR further ranks patients with similar clinical outcomes by durations of antibiotic therapy. Thus, RADAR is used to ‘break ties’ between patients with the same clinical outcome ranking. For example, a patient with clinical benefit and no adverse effects who is on antibiotics for 3 days is ranked higher than a patient with the same clinical outcome but who is on antibiotics for 6 days.”
Among patients who received short-course therapy, 71.98% recovered from their infection with no complications, 6.61% developed an extra-abdominal infection, 4.67% developed a surgical site or wound infection, 15.56% had a recurrent IAI requiring a procedure, and 1.17% died. Meanwhile, among those who received a traditional duration of therapy, 73.08% recovered with no complications, 4.62% developed an extra-abdominal infection, 8.08% developed a surgical site or wound infection, 13.46% had a recurrent IAI requiring a procedure, and 0.77% died.
When using DOOR, the probability that a randomly selected patient would have better outcomes if they received short-course antibiotics was 49.33% (95% CI, 46.20%-54.44%), according to the researchers. When applying RADAR to their estimates, the probability increased to 63.64% (95% CI, 58.63%-68.69%).
Celestin and colleagues tested the DOOR/RADAR method on a smaller sample size of 150 patients (75 per group) to determine whether they would reach similar conclusions. In this analysis, the probability of an improved DOOR score was 66.3% among patients who received short-course therapy.
“The current report ... suggests that a short duration of antibiotic therapy is superior to a longer duration of therapy for complicated intra-abdominal infection,” the researchers concluded. “By careful prospective choice of ordinal ranking levels and the use of the supporting analyses described above, we believe that future studies will confirm DOOR/RADAR as an advantageous methodology that allows stronger conclusions to be drawn from smaller samples sizes.” – by Stephanie Viguers
Disclosure: Celestin reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.