Pneumonia is the most frequent hospital infection in patients admitted to intensive care units (ICU) and is also responsible for the highest lethality rates, as well as an increase in both the duration and costs of hospitalization. The objective of this study was to identify predisposing factors for pneumonia. A prospective cohort study was carried out between June 1996 and June 1997, and included 540 patients admitted consecutively for periods greater than 24 hours to the adult ICU of the Londrina State University's Teaching Hospital. Of these, 83 (15.4%) developed pneumonia. All patients were analyzed with respect to various risk factors for hospital-acquired pneumonia. Univariate analysis identified the following factors: decreased level of...