Mortality from invasive pneumococcal pneumonia in the era of antibiotic resistance, 1995-1997

Objectives. This study examined epidemiologic factors affecting mortality from pneumococcal pneumonia in 1995 through 1997. Methods. Persons residing in a surveillance area who had community-acquired pneumonia requiring hospitalization and Streptococcus pneumoniae isolated from a sterile site were included in the analysis. Factors affecting mortality were evaluated in univariate and multivariate analyses. The number of deaths from pneumococcal pneumonia requiring hospitalization in the United States in 1996 was estimated. Results. Of 5837 cases, 12% were fatal. Increased mortality was associated with older age, underlying disease, Asian race, and residence in Toronto/Peel, Ontario. When these factors were controlled for, increased mortality was not associated with resistance to penicillin or cefotaxime. However, when deaths during the first 4 hospital days were excluded, mortality was significantly associated with penicillin minimum inhibitory concentrations of 4.0 or higher and cefotaxime minimum inhibitory concentrations of 2.0 or higher. In 2996, about 7000 to 12500 deaths occurred in the United States from pneumococcal pneumonia requiring hospitalization. Conclusions. Older age and underlying disease remain the most important factors influencing death from pneumococcal pneumonia. Mortality was not elevated in most infections with beta-lactam-resistant pneumococci.