Mortality, morbidity, and disease severity of patients with aspiration pneumonia

BACKGROUND Aspiration pneumonia is a common syndrome, although less well characterized than other pneumonia syndromes. We describe a large population of patients with aspiration pneumonia. METHODS In this retrospective population study, we queried the electronic medical records at a tertiary‐care, university‐affiliated hospital from 1996 to 2006. Patients were initially identified by International Classification of Diseases, 9th Revision code 507.x; subsequent physician chart review excluded patients with aspiration pneumonitis and those without a confirmatory radiograph. Patients with community‐acquired aspiration pneumonia were compared to a contemporaneous population of community‐acquired pneumonia (CAP) patients. We compared CURB‐65 (a clinical prediction rule based on Confusion, Uremia, Respiratory rate, Blood Pressure, and age)–predicted mortality with actual 30‐day mortality. RESULTS We identified 628 patients with aspiration pneumonia, of which 510 were community‐acquired. Median age was 77 years, with 30‐day mortality of 21%. Compared to CAP patients, patients with community‐acquired aspiration pneumonia had more frequent inpatient admission (99% vs 58%) and intensive care unit admission (38% vs 14%), higher Charlson comorbidity index (3 vs 1), and higher prevalence of do not resuscitate/intubate orders (24% vs 11%). CURB‐65 predicted mortality poorly in aspiration pneumonia patients (area under the curve, 0.66). CONCLUSIONS Patients with community‐acquired aspiration pneumonia are older, have more comorbidities, and demonstrate higher mortality than CAP patients, even after adjustment for age and comorbidities. CURB‐65 poorly predicts mortality in this population. Journal of Hospital Medicine 2013;8:83–90. © 2012 Society of Hospital Medicine