Predictors of early mortality in very elderly patients with bacteremia: a prospective multicenter cohort

Abstract

Objectives: The proportion of very elderly people in the population is increasing, and infectious diseases in this patient group may present with specific characteristics. The objective of this study was to investigate the outcome predictors of bacteremia among the very elderly.

Methods: This was a multicenter prospective cohort study of bloodstream infections (BSI) in patients ≥ 80 years old in 15 hospitals in Spain. The outcome variables were 14-day and 30-day mortality. Multivariate analysis was performed.

Results: One hundred and twenty episodes were included. Mortality was 22% (n = 26) on day 14 and 28% (n = 34) on day 30. In the univariate analysis, the variables associated with mortality were neutropenia, recent surgery, Pitt score ≥ 2, intensive care unit (ICU) admission, severe sepsis or shock, and abdominal, unknown, and respiratory tract sources. In the multivariate analysis, variables associated with mortality on day 14 were high-risk source (abdominal, unknown, and respiratory tract sources; odds ratio (OR) 7.9, 95% confidence interval (CI) 1.8-33.9), Pitt score ≥ 2 (OR 5.6, 95% CI 1.3-23.3), inadequate empirical treatment (OR 11.24, 95% CI 1.6-80.2), and severe sepsis or shock at presentation (OR 5.3, 95% CI 1.4-20.7); the interaction between empiric treatment and high-risk source was significant. On day 30, mortality was independently related to a high-risk source (OR 2.92, 95% CI 1.1-7.5) and presentation with severe sepsis or shock (OR 3.81, 95% CI 1.2-12.4).

Conclusions: Presentation with severe sepsis or shock and a high-risk source of BSI were independent predictors of 14-day and 30-day mortality. Inadequate empirical treatment was also a predictor of early mortality in patients with a high-risk source.

Keywords: Bacteremia; Mortality; Very elderly.