The Clinical Impact of Cirrhosis on the Hospital Outcomes of Patients Admitted With Influenza Infection: Propensity Score Matched Analysis of 2011-2017 US Hospital Data

Abstract

Background/objectives: Patients with cirrhosis have liver-related immune dysfunction that potentially predisposes the patients to increased influenza infection risk. Our study evaluates this cross-sectional relationship using a national registry of hospital patients.

Methods: This study included the 2011-2017 National Inpatient Sample database. From this, respiratory influenza cases were isolated and stratified using the presence of cirrhosis into a cirrhosis-present study cohort and cirrhosis-absent controls; propensity score matching method was used to match the controls to the study cohort (cirrhosis-present) using a 1:1 matching ratio. The endpoints included mortality, length of stay, hospitalization costs, and influenza-related complications.

Results: Following the match, there were 2,040 with cirrhosis and matched 2,040 without cirrhosis admitted with respiratory influenza infection. Compared to the controls, cirrhosis patients had higher in-hospital mortality (7.79 vs 3.43% p < 0.001, OR 2.38 95% CI 1.78-3.17), longer length of stay (7.25 vs 6.52 d p < 0.001), higher hospitalization costs ($70,009 vs $65,035 p < 0.001), and were more likely be discharged to a skilled nursing facility and home healthcare (vs routine home discharges). In terms of influenza-related complications, the cirrhosis cohort had higher rates of sepsis (29.8 vs 22% p < 0.001, OR 1.51 95% CI 1.31-1.74). In the multivariate regression analysis, cirrhosis was associated with higher mortality (p < 0.001, aOR 2.31 95% CI 1.59-3.35) and length of stay (p = 0.018, aOR 1.03 95% CI 1.01-1.06). In subgroup analysis of patients with decompensated (n = 597) versus compensated cirrhosis (n = 1443), those with decompensated cirrhosis had higher rates of in-hospital mortality (12.7 vs 5.75% p < 0.001, OR 2.39 95% CI 1.72-3.32), length of stay (8.85 vs 6.59 d p < 0.001), and hospitalization costs ($92,858 vs $60,556 p < 0.001). In the multivariate analysis, decompensated cirrhosis was associated with increased mortality (p < 0.001, aOR 2.86 95% CI 1.90-4.32).

Conclusion: This study shows the presence of cirrhosis to result in higher hospital mortality and postinfluenza complications in patients with influenza infection.

Keywords: AHRQ, agency for healthcare research and quality; DRG, diagnosis-related group; HCUP, healthcare cost and utilization project; ICD-10, international classification of diseases, tenth edition; ICD-9, international classification of diseases, ninth edition; NIS, nationwide inpatient sample; SBP, spontaneous bacterial peritonitis; SID, state inpatient database; VIF, variation inflation factor; ascites; common cold; flu; influenza-related complications; portal hypertension.

Figure 1

Flow-diagram outlining the cohort selection procedures of the study.

Figure 2

Forest plot representation of the multivariate e regression analysis using mortality as the primary endpoint in patients admitted with respiratory influenza infection.

Figure 3

Forest plot representation of the multivariate regression analysis using hepatic decompensation as an independent variable and mortality as the primary endpoint in cirrhosis patients admitted with respiratory influenza infection.