Short Versus Longer Antibiotic Duration for Community-Acquired Pneumonia : A Multicenter Target Trial Emulation.

Abstract

Shorter antibiotic courses for community-acquired pneumonia (CAP) may reduce adverse effects and resistance. However, real-world data supporting very short durations remain limited. To evaluate the safety and effectiveness of 3- to 4-day versus 5-day or more antibiotic durations in hospitalized patients with CAP who achieve clinical stability by day 3 (afebrile, no new oxygen, and stable vital signs). Observational emulation of a target trial. 67 Michigan hospitals between 2017 and 2024. Adults hospitalized (non-intensive care unit) with CAP who received 3 days of antibiotics, were clinically stable by antibiotic day 3, and met the strict eligibility criteria of the Pneumonia Short Treatment trial. 0 to 1 additional days of antibiotic treatment versus 2 or more days of additional antibiotic treatment (that is, shorter [3 to 4 days] vs. longer [≥5 days] total antibiotic duration). The main outcome was 30-day all-cause mortality. Other outcomes included 30-day hospital readmission, urgent health care visits, and <i>Clostridioides difficile</i> infection. Among 55 517 hospitalized patients with CAP, 5620 (10.1%) ultimately met eligibility criteria for short-course therapy after comorbidity, clinical stability, and treatment duration criteria were applied. Median age of eligible patients was 68.2 years, and 54.3% were men. Median antibiotic duration was 7 days, with only 7.9% (444 of 5620) receiving 3 to 4 days. Thirty-day adjusted risk ratios for short- versus long-course antibiotic therapy were 0.89 for mortality (95% CI, 0.01 to 2.25), 1.07 for readmission (CI, 0.81 to 1.42), 0.94 for urgent visit (CI, 0.70 to 1.28), and 1.01 for <i>C difficile</i> infection (CI, 0.18 to 5.68). Few short-duration patients and potential residual confounding. Only 10.1% of inpatients with CAP met the strict eligibility criteria for short-course therapy. The short- and longer-course antibiotic treatment groups had similar mortality rates, and there was little difference in benefits and harms. Blue Cross Blue Shield of Michigan and Blue Care Network.