Natural History of Hepatic Steatosis: Observed Outcomes for Subsequent Liver and Cardiovascular Complications

OBJECTIVE. Hepatic steatosis is a common incidental finding at radiologic imaging. The natural history of nonalcoholic fatty liver disease (NAFLD) and its associated risks for cardiovascular complications are not well established in this context. Our purpose was to investigate the clinical outcome of moderate-to-severe hepatic steatosis detected incidentally at CT. MATERIALS AND METHODS. Liver attenuation was measured at unenhanced CT in 4412 consecutive adults scanned over a 12-month period. Moderate-to-severe steatosis was diagnosed by liver attenuation less than or equal to 45 HU, which is essentially 100% specific for histologic grading of 30% or more fat content. The control group was defined by a high-normal liver attenuation of 60–65 HU. The main exclusion criteria were preexisting liver disease (beyond asymptomatic NAFLD), alcoholism, or less than 1 year of clinical follow-up. A medical record review assessed for the development of symptomatic liver disease (including nonalcoholic steatohepatitis ...