Ascertainment of liver disease and related mortality

The outcomes of interest included overall liver disease, NAFLD, liver cirrhosis, HCC, chronic liver disease (CLD), severe liver disease (SLD), liver disease–specific mortality, CLD-specific mortality, and SLD-specific mortality. These outcomes were considered based on clinical significance and the prevalence in the study population. Overall liver disease was the composite outcome of all studied liver diseases. NAFLD was the most common liver comorbidity in patients with T2DM.⁵ Cirrhosis and HCC were important life-threatening liver end points.⁵ Two common composite end points, CLD (fibrosis, cirrhosis, alcohol-associated liver diseases, and chronic hepatitis) and SLD (cirrhosis, decompensated liver disease, HCC, and liver transplantation), were included.^20,21 The ranges of these 2 composite end points overlap somewhat, but CLD emphasizes the protracted course of the disease, while SLD emphasizes the severity of the disease, both of which are composite life-threatening end points widely used in research.^20,21

These outcomes were identified through inpatient data, primary care data, cancer registry, and death registry. ICD codes (ICD-10) used for these outcomes are presented in Supplemental Table S2, http://links.lww.com/HC9/A605. Self-reported information was also considered to exclude prevalent events. Cause-specific mortality was identified using the ICD-10 code recorded in the contributory or underlying cause of death. The Audit Commission review of 2009-2010 showed that the overall accuracy of ICD-10 diagnostic codes was 89%.²².