Azithromycin plus β-lactam versus levofloxacin plus β-lactam for severe community-acquired pneumonia: A retrospective nationwide database analysis.

Previous studies showed potential benefits of macrolide combined with β-lactam for severe community-acquired pneumonia (CAP). However, it remains inconclusive whether macrolide plus β-lactam is superior to respiratory fluoroquinolone plus β-lactam for patients with severe CAP. Using a nationwide inpatient database in Japan, we performed propensity score matching and inverse probability of treatment weighting (IPTW) to compare 28-day mortality and in-hospital mortality between azithromycin plus β-lactam and levofloxacin plus β-lactam for severe CAP patients admitted to hospital between July 2010 and March 2015. We identified 1,999 patients with severe pneumonia who received azithromycin plus β-lactam (n = 840) or levofloxacin plus β-lactam (n = 1,159) within 2 days after admission. Five-hundred sixty propensity score-matched pairs showed no significant differences between azithromycin plus β-lactam and levofloxacin plus β-lactam in 28-day mortality and in-hospital mortality (19.3% vs. 20.7%, p = 0.601 and 24.8% vs. 26.8%, p = 0.495, respectively). IPTW analysis also showed no significant differences between azithromycin plus β-lactam and levofloxacin plus β-lactam in 28-day mortality (risk difference, -3.5% [95% confidence interval, -8.8% to 1.7%] and in-hospital mortality (risk difference, -3.6%; 95% confidence interval, -9.4% to 2.1%). In conclusion, there were no significant differences in 28-day mortality and in-hospital mortality between azithromycin plus β-lactam and levofloxacin plus β-lactam for severe CAP patients.