Nursing home residence is the main risk factor for increased mortality in healthcare-associated pneumonia

Healthcare-associated pneumonia (HCAP) is considered to represent a category of disease distinct from community-acquired pneumonia (CAP). We describe the incidence and characteristics of HCAP compared with CAP in patients hospitalised through the emergency department (ED). Pneumonia diagnosed at the ED of Ghent University Hospital from 1 November 2006 to 31 October 2007 was retrospectively categorised as CAP or HCAP according to the definition of the American Thoracic Society/Infectious Diseases Society of America. We categorised 287 episodes of pneumonia, diagnosed in 269 patients, as CAP [159 (55%)] or HCAP [128 (45%)]. Patients with HCAP were older [75 years (range: 64-83) vs 68 (41-78); P < 0.001], had more comorbidity, and had more severe pneumonia [CURB-65: 2 (1-3) vs 1 (0-2); P < 0.001] in comparison to patients with CAP. Patients with HCAP had more frequently an unfavourable clinical course (27% vs 15%; P < 0.01) and a longer hospital stay (12 days vs 9 days; P<0.001) compared with patients with CAP. In multivariate regression analysis, nursing home residence (odds ratio: 2.96; 95% confidence interval: 1.12-7.84; P = 0.03) but not HCAP was an independent predictor for in-hospital mortality. In conclusion, a high percentage (45%) of patients hospitalised with pneumonia through the ED was classified as HCAP. Classification as HCAP was associated with an unfavourable clinical course. Nursing home residence was an independent predictor for increased mortality.