Outcome of community-acquired pneumonia: influence of age, residence status and antimicrobial treatment

Community-acquired pneumonia remains a major cause of mortality in developed countries. There is much discrepancy in the literature regarding factors influencing the outcome in the elderly population. Data were derived from a multicentre prospective study initiated by the German Competence Network for Community-Acquired Pneumonia. Patients with community-acquired pneumonia (n=2,647; 1,298 aged <65 yrs and 1,349 aged,65 yrs) were evaluated, of whom 72.3% were hospitalised and 27.7% treated in the community. Clinical history, residence status, course of disease and antimicrobial treatment were prospectively documented. Microbiological investigations included cultures and PCR of respiratory samples and blood cultures. Factors related to mortality were included in multivariate analyses. The overall 30-day mortality was 6.3%. Elderly patients exhibited a significantly higher mortality rate that was independently associated with the following: age; residence status; confusion, urea, respiratory frequency and blood pressure (CURB) score; comorbid conditions; and failure of initial therapy. Increasing age remained predictive of death in the elderly. Nursing home residents showed a four-fold increased mortality rate and an increased rate of Gram-negative bacillary infections compared with patients dwelling in the community. The CURB score and cerebrovascular disease were confirmed as independent predictors of death in this subgroup. Age and residence status are independent risk factors for mortality after controlling for comorbid conditions and disease severity. Failure of initial therapy was the only modifiable prognostic factor.