Study Design and Patient Population
We performed a retrospective study of all patients diagnosed with cirrhosis and admitted to UC Davis Medical Center (UCDMC) between January 1, 2013 and January 1, 2018, a tertiary care academic medical center. Any available data prior to January 1, 2013 was not analyzed to emphasize the most current data available. Medical chart review was performed of the UCDMC electronic medical records, with patients identified initially based on the International Classification of Diseases (ICD-10) for cirrhosis or its complications. On October 1, 2015, ICD-10 became available in the United States. At that time, our electronic health record system (Epic Systems, Verona, WI) automatically converted all existing ICD-9 codes to the equivalent ICD-10 codes. Thus, during data abstraction for this study, all codes had been converted to ICD-10 codes.The specific (ICD-10) codes used to determine cirrhosis and complications of cirrhosis included, alcoholic cirrhosis of the liver without ascites (K70.30), alcoholic cirrhosis of the liver with ascites (K70.31), unspecified cirrhosis of the liver (K74.60), other cirrhosis of the liver (K74.69) esophageal varices with bleeding (I85.01), gastric varices (I86.4), hepatic failure, unspecified with coma (K72.91), other ascites (R18.8) or spontaneous bacterial peritonitis (SBP) (K65.2). Demographic information, laboratory data, medical comorbidities, insurance, adherence to cirrhosis quality care indicators, 30 and 90-day readmission, and 30 and 90 day mortality were recorded for analysis. Median income was determined by zip code using a publically available online database (Income By Zip Code) of the American Community Survey 2017 5-year estimates. This study was approved by the Institutional Review Board at UCDMC.
For our study, we focused on the 3 major types of insurance in the United States: Medicare, Medicaid, and private insurance. Both Medicare and Medicaid are federal insurance programs. Medicare covers patients ages 65 and older (or ages less than 65 with a disability and dialysis patients). Medicaid covers low-income patients regardless of age. Lastly, private insurance is purchased by individuals or their employers. Thus, American patients with higher income are more likely to hold private insurance.
Adherence to Cirrhosis Quality Indicators
We determined adherence to cirrhosis quality indicators by assessing the following: receiving beta-blockers at discharge for secondary prophylaxis after being admitted for variceal bleed, receiving prophylactic antibiotics (IV ceftriaxone or equivalent) in the setting acute variceal hemorrhage, receiving diuretics at discharge for medium to large ascites in the absence of renal failure, receiving spontaneous bacterial peritonitis (SBP) prophylaxis at discharge with after diagnosis and treatment of SBP, receiving intravenous albumin as an inpatient in the setting acute SBP (1.5 g/kg IV on day 1, then 1g/kg on day 3), receiving IV antibiotics (cefotaxime or equivalent) for treatment of SBP, and receiving lactulose and/or rifaximin for hepatic encephalopathy (HE). Patients who did not receive this level of care in any of these categories were counted as non-adherent for our analyses for each respective category.
Descriptive data was reported as percentages, means ± SD and medians (with range and confidence interval when appropriate). For comparative analytics, we used Kruskal-Wallis test for continuous/numerical variables and Fisher’s exact test for categorical variables. Multivariable proportional odds regression analysis (hereafter called “multivariable regression analysis” unless otherwise specified) analysis was done to identify independent associations connected to racial disparities in cirrhosis related health care and their effect on readmissions and mortality. To create our multivariate regression models for 30 and 90-day readmissions and mortality, we adjusted for the following variables: ethnicity, MELD-Na, medical comorbidities (including diabetes, coronary artery disease, and chronic obstructive pulmonary disease), complications of cirrhosis (including hepatic encephalopathy, gastro-esophageal varices, ascites, and hepatocellular carcinoma), receipt of aforementioned quality cirrhosis care, English primary language, insurance status, and median income. A p value <0.05 was considered significant.