Hospital admission decisions for older Veterans with community-onset pneumonia: An analysis of 118 US Veterans Affairs Medical Centers

Objectives: Age is important for prognosis in community--onset pneumonia, but how it influences admission decisions in the emergency department (ED) is not well characterized. Using clinical data from the electronic health record in a national cohort, we examined pneumonia hospitalization patterns, variation, and relationships with mortality among older versus younger Veterans. Methods: In a retrospective cohort of patients = 18 years presenting to EDs with a diagnosis of pneumonia at 118 VA Medical Centers January 1, 2006, to December 31, 2016, we compared observed, predicted, and residual hospitalization risk for Veterans < 70, 70--79, and = 80 years of age using generalized estimating equations and machine learning models with 71 patient factors. We examined facility variation in residual hospitalization across facilities and explored whether facility differences in hospitalization risk correlated with differences in 30--day mortality. Results: Among 297,498 encounters, 165,003 (55%) were for Veterans < 70 years, 61,076 (21%) 70--80, and 71,419 (24%) = 80. Hospitalization rates were 52%, 67%, and 76%, respectively. After other patient factors were adjusting for, age 70--79 had an odds ratio (OR) of 1.39 (95% confidence interval [CI] 1.34--1.44) and = 80 had an OR of 2.1 (95% CI 2.0--2.2) compared to age < 70. There was substantial variation in hospitalization across facilities among Veterans < 70 (<35% hospitalization at the lowest decile of facilities vs. > 66% at the highest decile) that was similar but with higher risk for patients 70--79 years (54% vs. 82%) and = 80 years (59% vs. 85%) and remained after accounting for patient factors, with no consistently positive or negative associations with facility--level 30- -day mortality. Conclusions: Older Veterans with community--onset pneumonia experience high risk of hospitalization, with widespread facility variation that has no clear relationship to short--term mortality.