The Burden of Community-Acquired Pneumonia Requiring Admission to an Intensive Care Unit in the United States.

Abstract Background A paucity of studies have assessed the epidemiology of community-acquired pneumonia (CAP) requiring intensive care unit (ICU) admission. We conducted a study on this group of patients with the primary objective of defining the incidence, epidemiology and mortality of CAP in the ICUs in Louisville, KY. The secondary objective was to estimate the number of patients hospitalized and the number of deaths associated with CAP in ICU in the US. Methods This was a secondary analysis of a prospective population-based cohort study. The setting was all nine adult hospitals in Louisville, KY. The annual incidence of CAP in the ICU per 100,000 adults was calculated for the whole adult population of Louisville. The number of patients hospitalized due to CAP in ICU in the US was estimated by multiplying the Louisville incidence rate of CAP in ICU by the 2014 US adult population. Results From a total of 7,449 unique patients hospitalized with CAP, 1,707 (23%) were admitted to ICU. The incidence of CAP in the ICU was 145 cases per 100,000 population of adults. Cases of CAP in the ICU were clustered in patients from areas of the city with high poverty. The mortality of patients with CAP in ICU was 27% at 30 days and 47% at 1 year. In the US, the estimated number of patients hospitalized with CAP requiring ICU was 356,326 per year, and the estimated number of deaths at 30 days and one year was 96,206 and 167,474, respectively. Conclusions Almost one in five patients hospitalized with CAP requires intensive care. Poverty is associated with CAP in the ICU. Nearly half of patients with CAP in the ICU will die within one year. Due to its significant burden, CAP in the ICU should be a high priority in research agenda and health policy.