The burden of hospitalised pneumonia in Lazio, Italy, 1997-1999

OBJECTIVE: To evaluate the burden of hospitalised pneumonia in adults in the Lazio region (1997-1999); to describe community-acquired pneumonia (CAP), suspected nosocomial infection (NI) and AIDS-related pneumonia. METHODS: Using data from the Hospital Information System, we traced the hospitalisation history of patients and classified CAP, NI and AIDS-related pneumonia. RESULTS: During the study period, 30517 incident events of pneumonia occurred: 20 497 CAP, 9760 NI, and 964 AIDS-related pneumonia; 704 of these were also NI (annual incidence rate 158, 75 and 7.4 per 100 000 population, respectively). The mean ages were 65, 69 and 38 years for CAP, NI, and AIDS-related pneumonia, respectively. Higher hospitalisation rates were observed in Rome than in the rest of the region for NI and AIDS-related cases, but not for CAP. Lower socio-economic groups showed a higher incidence of CAP and AIDS-related pneumonia. Peaks of incidence were observed in winter for CAP and NI. Only 20% of pneumonias have an aetiological diagnosis. In-hospital fatality rates were 9.4%, 29.3% and 11.2% for CAP, NI and AIDS-related pneumonia, respectively. CONCLUSION: The high incidence and fatality of CAP and NI, especially among the elderly, makes these diseases a problem that is re-emerging in industrialised countries with an ageing population.