90-day Case-Fatality in Critically ill Patients with Chronic Liver Disease Influenced by Presence of Portal Hypertension, Results from a Multicentre Retrospective Cohort Study

Background Critical illness in patients with chronic liver disease (CLD) is increasing in occurrence, and by virtue of its adverse effect on prognosis, its presence may influence the decision to offer admission to intensive care units (ICU). Our objective was to examine the determinants and outcome of patients with CLD admitted to ICU. Methods A retrospective cohort of patients admitted to four adult ICUs in Queensland, Australia from 2017 to 2019. Patients with mild or moderate-severe CLD were defined by the absence and presence of portal hypertension, respectively, and were was determined using granular ICU and state-wide administrative databases. The primary outcome was 90-day all cause case-fatality. Results We included 3836 patients in the analysis, of which, 60 (2%) had mild liver disease and 132 (3%) had moderate-severe liver disease . Patients with CLD had higher incidence of other co-morbidities with the median adjusted-Charlson co-morbidity index (CCI) was 1 (interquartile range; IQR 0-3) for no CLD, 2 (IQR 1.5-4) for mild CLD, and 3 (IQR 2-5) for moderate-severe CLD. Case-fatality rates at 90 days was 17% for no CLD, 25% for mild CLD, and 41% for moderate-severe CLD. Among those with mild and moderate-severe CLD, an increased co-morbidity burden as measured by an adjusted CCI score of low (0-3), medium (4-5), high (6-7) and very high (>7) resulted in increasing case-fatality rates of 24-40%, 11-28.5%, 33-62%, and 50% respectively. Moderate-severe CLD, but not mild CLD, was independently associated with increased case-fatality at 90 days (Odds Ratio 1.58; 95% confidence interval 1.01-2.48; p = 0.004) after adjusting for medical co-morbidities and severity of illness using logistic regression analysis. Conclusions Although patients with moderate-severe CLD have an increased risk for 90-day case-fatality, patients with mild CLD are not at higher risk for death following ICU admission.