Impact of intravenous β-lactam/macrolide versus β-lactam monotherapy on mortality in hospitalized patients with community-acquired pneumonia

Objectives: Guidelines recommend dual-therapy consisting of a β-lactam/macrolide (BLM) for hospitalized patients with community-acquired pneumonia. Nevertheless, the superiority over β-lactam-monotherapy (BL) remains unproven. Methods: Analyses froman observational study initiated by the German competence network CAPNETZ were performed. Results: One thousand eight hundred and fifty-four patients were treated with either BL (49.0%) or BLM (51.0%). BLM therapy was associated with lower adjusted 14 day mortality [odds ratio (OR) 0.53; 95% confidence interval (CI): 0.30-0.94]. CRB65, neoplastic disease, age and nursing home residency were confirmed as independent predictors of death. Adjusted 14 day mortality risk was clearly reduced in patients with CRB65 = 2 (n = 411; OR 0.35; CI: 0.12-0.99) and CRB65 ≥ 2 (n = 519; OR 0.42; CI: 0.18-0.997). However, this could not be shown for adjusted 30 day mortality. Patients with CRB65 ≤1 showed low mortality (2.1%) without the influence of BLM. BLM therapy was associated with lower adjusted risk of treatment failure at 14 days (n = 1854; OR 0.65; CI: 0.47-0.89) and 30 days (OR 0.69; CI: 0.51-0.94) as well as in the subgroup of patients with CRB65 = 2 and CRB65 ≥2. Conclusions: This study suggests the superiority of BLM therapy in patients with CRB65 risk classes of 2 or higher on 14 day mortality. BLM therapy was also associated with lower risk of treatment failure.