Hospital-acquired pneumonia incidence and diagnosis in older patients

Background: hospital-acquired pneumonia poses a hazard to older people who are hospitalised, yet few data exist on the incidence or risk factors in non-intensive care patients. This study aimed to determine the incidence of hospital-acquired pneumonia (HAP) in a sample of hospitalised older people. Methods: prospective survey of hospitalised older patients (>65 years) at a single centre over a 12-month period. Casenote and chart data were collected on acute medical, orthopaedic and Medicine for the Elderly wards. HAP was defined in accordance with the European and Scottish National Prevalence Survey 2011 definition. Key analyses were incidence of clinically suspected and case definition clinically confirmed HAP. Results: one thousand three hundred and two patients were included in the analysis. Five hundred and thirty-nine (41%) were male; mean age was 82 years (SD 8). Median length of hospital stay was 14 days (IQR 20). One hundred and fifty-seven episodes of HAP were clinically suspected in 143 patients (10.9% of admissions), but only 83 episodes in 76 patients met the diagnostic criteria (5.8% of admissions). The risk of HAP was 0.3% per day in hospital. Reasons for failure to meet the diagnostic criteria in 75 cases were lack of radiographic evidence in 60/75; lack of evidence of inflammation in 42/75, and lack of respiratory signs or symptoms in 13/75; 35/75 (47%) of cases lacked evidence in two or more domains. Conclusion: HAP is common but over-diagnosed in older hospitalised patients.