The objective of this study was to determine the mortality of patients with dementia or stroke hospitalized with community-acquired pneumonia (CAP) in the city of Louisville.

Dementia and stroke are two major comorbidities in elderly patients admitted with CAP. These comorbidities are associated with higher hospitalization rates and act as barriers to optimal recovery. There is limited data regarding the impact of dementia and stroke on the mortality of hospitalized patients with CAP.

This was a secondary analysis of the University of Louisville Pneumonia Study (ULPS) database. From ULPS, patients aged 18 years and above admitted due to CAP in 9 major Louisville hospitals from October 1^st 2016 to March 31^st 2017 were included in this study. Patients were followed to define mortality during 4 periods: in-hospital, 30-days, 6-months, and 1 year. Mortality was compared to data from all patients in ULPS using chi-squared tests of homogeneity. P-values less than 0.05 were considered significant.

From a total of 1,760 patients hospitalized with CAP, dementia was identified in 73(4%) patients, and stroke was identified in 235(13%) patients. Mortality of all hospitalized patients with CAP compared to those with dementia were as follows: In-Hospital 6.5% vs. 7% (p=0.811), 30 days 13% vs. 20% (p=0.105), 6 months 23.4% vs. 47% (p<0.001), and 1 year 30.6% vs. 69% (p<0.001). Mortality of all hospitalized patients with CAP compared to those with stroke were as follows: In-Hospital 6.5% vs. 4% (p=0.213), 30 days 13% vs. 11% (p=0.452), 6 months 23.4% vs. 26% (p=0.507), and 1 year 30.6% vs. 41% (p=0.004).

This study indicates that patients with dementia or stroke hospitalized with CAP have a significant increase in risk of long term mortality. An episode of pneumonia may accelerate underlying comorbidities and predispose to premature death in patients with dementia and stroke.