Timing of antibiotic administration and outcomes of hospitalized patients with community-acquired and healthcare-associated pneumonia.

The effects of antibiotic timing on outcomes of patients with community-acquired pneumonia (CAP) are controversial. Moreover, no information is available regarding this issue in healthcare-associated pneumonia (HCAP). We aimed to determine the impact of antibiotic timing on 30-day mortality of patients with CAP and HCAP. Non-immunocompromised adults admitted to hospital through the emergency department (ED) with community-onset pneumonia were prospectively observed from 2001 to 2009. Patients who received prior antibiotics were excluded. Of 1593 patients with pneumonia who were analyzed, 1274 had CAP and 319 HCAP. The mean time from patient arrival at the ED until antibiotic administration was 5.8 h (standard deviation (SD) 3.5) in CAP and 6.1 h (SD 3.8) in HCAP (p 0.30). Mortality was higher in patients with HCAP (5.5% vs. 13.5%; p <0.001). After adjusting for confounding factors in a logistic regression analysis, the antibiotic administration ≤4 h was not associated with decreased 30-day mortality in patients with CAP (odds ratio (OR) 1.12, 95% confidence interval (CI) 0.57-2.21) and in patients with HCAP (OR 0.59, 95% CI 0.19-1.83). Similarly, antibiotic administration ≤8 h was not associated with decreased 30-day mortality in CAP (OR 1.58, 95% CI 0.64-3.88) and HCAP patients (OR 0.59, 95% CI 0.19-1.83). In conclusion, antibiotic administration within 4 or 8 h of arrival at the ED did not improve 30-day survival in hospitalized adults for CAP or HCAP.