Hyperbilirubinemia in hospitalized patients: Etiology and outcomes

There is little information on the differential diagnosis and prognosis of hospitalized patients with hyperbilirubinemia. Here, we hypothesized that hyperbilirubinemia in hospitalized patients is associated with specific diseases and outcomes. This retrospective cohort analysis included patients admitted to the Medical University of South Carolina with a total bilirubin >3 mg/dL from January 9, 2015 to August 25, 2017. Collected clinical data included demographics, primary diagnosis, Charlson Comorbidity Index (CCI), laboratory data, and clinical outcomes. We separated and analyzed the cohort into seven primary diagnostic groups. We identified 1693 patients with a bilirubin level >3 mg/dL. The cohort was 42% female, had an average age of 54, average CCI of 4.8, and average length of stay of 13 days. The causes of hyperbilirubinemia included the following: primary liver disease (868/1693; 51%) with cirrhosis being most common (385/1693; 23%), benign biliary obstruction (252/1693; 15%), hemolytic anemia (149/1693; 9%), malignant biliary obstruction (121/1693; 7%), unknown etiology (108/1693; 6%), primary liver cancer (74/1693; 4%), and metastatic cancer to the liver (57/1693; 3%). Overall, the mortality/discharge to hospice rate in patients with a bilirubin >3 mg/dL was 30%, and was proportional to the severity of hyperbilirubinemia, including when controlling for the underlying severity of illness. Mortality was highest in patients with primary liver disease and malignancy and was lowest in patients with non-cancerous obstruction or hemolytic jaundice. Hyperbilirubinemia in hospitalized patients is most often due to primary liver disease, and identifies patients with a poor prognosis, particularly when caused by primary liver disease or cancer.