LAUSR

BACKGROUND Over five million Americans suffer from heart failure (HF), and this is associated with multiple chronic comorbidities and recurrent decompensation. Currently, there is an increased incidence in vaccine-preventable diseases (VPDs). We aim to investigate the impact of HF with reduced ejection fraction (HFrEF) in patients hospitalized with VPDs. HYPOTHESIS Patient with HFrEF are at higher risk for VPDs and they carry a higher risk for in-hospital complications. METHODS Retrospective analysis from all hospital admissions from the 2016-2018 National Inpatient Sample (NIS) using the ICD-10CM codes for patients admitted with a primary diagnosis of VPDs with HFrEF and those without reduced ejection fraction. Outcomes evaluated were in-hospital mortality, length of stay (LOS), healthcare utilization, frequency of admissions, and in-hospital complications. Multivariate regression analysis was conducted to adjust for confounders. RESULTS Out of 317 670 VPDs discharges, we identified 12 130 (3.8%) patients with HFrEF as a comorbidity. The most common admission diagnosis for VPDs was influenza virus (IV) infection (75.0% vs. 64.1%; p < .01), followed by pneumococcal pneumonia (PNA) (13% vs. 9.4%; p < .01). After adjusting for confounders, patients with HFrEF had higher odds of having diagnosis of IV (adjusted [aOR], 1.42; p < .01) and PNA (aOR, 1.27; p < .01). Patients with VPDs and HFrEF had significantly higher odds of mortality (aOR, 1.76; p < .01), LOS, respiratory failure requiring mechanical ventilation, and mechanical ventilation for less than 96 h. CONCLUSION Influenza and PNA were the most common VPDs admitted to the hospital in patients with a concomitant diagnosis of HFrEF. They were associated with increased mortality and in-hospital complications.