1514. Mortality and Readmission in Adults during the First Year Following Hospitalization for Community-Acquired Pneumonia in the US
Authors: Sato Reiko , Weycker Derek , Shaff Melody , Hanau Ahuva , Lonshteyn Alexander , Pelton Stephen I 
Published: January 2021

Abstract

Background
Increasing evidence suggests that the impact of community-acquired pneumonia (CAP) extends beyond discharge from the hospital and the acute phase of illness. We sought to characterize mortality and hospital readmission across the adult age span and spectrum of comorbidities.

Methods
A retrospective cohort design and data from Optum’s de-identified Integrated Claims-Clinical dataset (2009-2018) were employed. Study population comprised all adults who, between 1.1.2013 and 12.31.2017, had ≥ 1 acute-care hospitalization for CAP; each qualifying CAP hospitalization separated by ≥ 365 days was included as a unique observation in analyses. Study outcomes included acute-care hospital readmission for any reason and death for any reason. Hospital readmission was ascertained during the 360-day period following discharge from the CAP hospitalization; death was ascertained during the CAP hospitalization as well as during the same 360-day period. Cumulative rates of mortality and readmission were summarized for all patients as well as subgroups defined on age and comorbidity profile (i.e., healthy, at-risk, high-risk).

Results
Study population totaled 37,006 patients who contributed 38,809 CAP hospitalizations; mean age was 71 years, 51% were female, and 88% had an at-risk (33%) or high-risk (55%) condition. Hospital readmission was 12.5% during the 30-day post-discharge period, and 42.3% during the 360-day post-discharge period. Mortality was 3.5% in hospital, 8.2% from admission to 30 days post-discharge, and 17.7% from admission to 360 days post-discharge. Mortality rates increased with age and severity of comorbidity profile; readmission rates were highest for persons aged 65-74 years and high-risk persons.
Rates of readmission and mortality among adults hospitalized for CAP

Conclusion
All-cause mortality up to 1 year following hospital admission for CAP was substantial, and was associated with increasing age and worsening comorbidity profile. Both readmission and mortality were greater at all ages in high-risk and at-risk groups compared with their healthy counterparts. Strategies that prevent pneumonia and/or the pathophysiologic changes that follow CAP, especially among individuals with comorbid conditions, have the potential to reduce morbidity and mortality following CAP as well as healthcare costs associated with readmission.

Disclosures
Reiko Sato, PhD, Pfizer, Inc (Employee, Shareholder) Derek Weycker, PhD, Pfizer Inc. (Consultant, Grant/Research Support, Scientific Research Study Investigator, Research Grant or Support) Melody Shaff, BA, Pfizer, Inc. (Consultant, Grant/Research Support, Scientific Research Study Investigator, Research Grant or Support) Ahuva Hanau, BS, Pfizer, Inc. (Consultant, Grant/Research Support, Scientific Research Study Investigator, Research Grant or Support) Alexander Lonshteyn, PhD, Pfizer, Inc. (Consultant, Grant/Research Support, Scientific Research Study Investigator, Research Grant or Support) Stephen I. Pelton, MD, Merck vaccine (Consultant, Grant/Research Support)Pfizer (Consultant, Grant/Research Support)Sanofi Pasteur (Consultant, Other Financial or Material Support, DSMB)Seqirus Vaccine Ltd. (Consultant)