Risk factors for 30-day mortality in elderly patients with lower respiratory tract infection: Community-based study

Background: Pneumonia is a major cause of death in the elderly, but there are few studies of risk factors for death that include both ambulatory and nursing home patients. Objective: To assess factors associated with 30- day mortality in a population-based study of older adults with lower respiratory tract infection. Methods: Identification of (1) a previously identified retrospective cohort of all residents of Rochester, Minn, aged 65 years or older who experienced a first episode of pneumonia or bronchitis during a calendar year and (2) the risk factors associated with 30-day mortality through review of complete inpatient and ambulatory medical records. Logistic regression was used to identify significant independent risk factors for 30-day mortality. Results: A total of 413 adults aged 65 years or older were identified. The independent factors for 30-day mortality were atypical symptoms (odds ratio [OR], 4.98; 95% confidence interval [CI], 2.14-11.60), neurologic illness (OR, 3.92; 95% CI, 1.47-6.59), current diagnosis of cancer (OR, 6.2; 95% CI, 2.40-15.99), and recent or current use of antibiotics (OR, 3.13; 95% CI, 1.45-6.77). Conclusions: Malignancy and neurologic disease are well-recognized conditions that identify patients with lower respiratory tract infections who have a high risk of death within 30 days. An atypical presentation with confusion, lethargy, poor eating, or recent or current antibiotic use also identifies patients with a high risk of 30-day mortality.