Poor Cardiorespiratory Fitness Is a Risk Factor for Sepsis in Patients Awaiting Liver Transplantation

Background. Patients with advanced liver disease are at increased risk of infection and other complications. A significant proportion of patients also have poor fitness and low muscle mass. The primary aim of this study was to investigate if cardiorespiratory fitness and body composition are risk factors for sepsis and other complications of advanced liver disease. Methods. Patients being listed for liver transplantation underwent cardiopulmonary exercise testing to determine ventilatory threshold (VT). Computed tomography was used to measure skeletal muscle and subcutaneous and visceral adipose tissue indexes. All unplanned hospital admissions, deaths or delistings before transplantation were recorded. Results. Eighty-two patients (aged 55.1 [50.6-59.4] years, median (interquartile range); male 87%] achieved a median VT of 11.7 (9.7-13.4) mL·kg^-1·min^-1. Their median model of end-stage liver disease, incorporating serum sodium score was 18 (14-22); and 37 had hepatocellular carcinoma. There were 50 admissions in 31 patients; with 16 admissions for sepsis in 13 patients. Patients with sepsis had a significantly lower VT (sepsis, 9.5 [7.8-11.9]; no sepsis, 11.8 [10.5-13.8] mL·kg^-1·min^-1; P = 0.003]. No body composition variables correlated with sepsis, nor were there any significant associations between VT and unplanned admissions for other indications. Multivariate logistic regression demonstrated that VT was independently associated with a diagnosis of sepsis (P = 0.03). Poisson regression revealed that VT was a significant predictor for the number of septic episodes (P = 0.02); independent of age, model of end-stage liver disease, incorporating serum sodium score, hepatocellular carcinoma diagnosis, presence of ascites, and β-blocker use. Conclusions. Poor cardiorespiratory fitness is an independent risk factor for the development of sepsis in advanced liver disease.