PURPOSE: Several investigators have suggested that healthcare-associated pneumonia (HCAP) patients are more similar to hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) patients than community-acquired pneumonia (CAP) patients. However, existing studies are limited by inconsistent application of the ATS-IDSA criteria for HCAP.
METHODS: We retrospectively reviewed the charts of all patients with a discharge ICD-9 code for pneumonia in 2008. Patients were rigorously stratified as CAP, HCAP, HAP or VAP using all existing ATS-IDSA defining criteria. We then compared groups regarding microbiology and clinical outcomes.
RESULTS: The study included 523 patients: 280 (53.5%) had HCAP, 161 (30.9%) had CAP, 42 (8.1%) had HAP and 40 (7.7%) had VAP. Microbiologic-confirmation of infection was established in 36.1%. Mean APACHE II scores were similar for HCAP and CAP patients (13.9±7.9 vs. 12.4±7.4, p=0.10); HAP/VAP patients had scores (17.7±8.0) which were higher than HCAP (p=0.001) and CAP (p<0.001) patients. The rate of infection with a resistant pathogen was similar for HCAP and HAP/VAP patients (21.1% vs. 26.8%, p=0.44) while CAP patients had rates (6.8%) which were significantly lower than HCAP and HAP/VAP (p<0.001 for each comparison). Hospital length of stay was not different for HCAP and CAP patients (7.6±7.2 days vs. 6.0±5.3 days, p=0.14) but both were significantly different from HAP/VAP patients (20.5±16.1 days, p<0.001 for each comparison). Mortality rate was not different for HCAP and CAP patients (10.7% vs. 6.2%, p=0.30); both had significantly lower mortality rates than HAP/VAP patients (20.7%, p=0.002 for CAP and p=0.03 for HCAP).
CONCLUSION: Our rigorous application of HCAP-defining criteria resulted in a higher incidence of HCAP than has been generally reported. Although HCAP patients had rates of infection by resistant pathogens that were more similar to HAP/VAP than CAP, severity of illness, length of stay, and mortality were more similar to CAP than HAP/VAP.
CLINICAL IMPLICATIONS: These data suggest that HCAP may be more similar to CAP and less similar to HAP/VAP than currently believed.
DISCLOSURE: Lee Morrow, No Financial Disclosure Information; No Product/Research Disclosure Information