Monitoring Changes in Hepatic Steatosis Using Continuous Controlled Attenuation Parameter

Background: Non-alcoholic fatty liver disease (NAFLD) affects 30% of the Asian adult population and is emerging as one of the important leading causes of liver cancer and cirrhosis. Although a number of biomarkersmany have been developed for the assessment of liver fat and fibrosis, most existing studies were cross-sectional in nature. The role of these biomarkers for monitoring and response assessment remains elusive. At present, magnetic resonance imaging proton density fat fraction (MRI-PDFF) is considered the gold standard to in quantifying liver fat. The MRI-PDFF response, defined as a ≥30% relative reduction in liver fat fraction, has been shown to correlate with improved hepatic inflammation and fibrosis. However, MRI is limited by cost and availability. The cContinuous controlled attenuation parameter (CAPc) measurement by vibration controlled transient elastography is a new technology to quantify liver fat. It is a point-of-care test and has the potential to replace the MRI-PDFF as a monitoring and response biomarker in routine practice. Study plan: This prospective cohort study will include 150 patients with NAFLD who will join a 6-month lifestyle modification programme involving dietary intervention and physical training. This will create a cohort of varying degrees of liver fat reduction. Using MRI-PDFF as the reference standard, we will evaluate the accuracy of a changes in CAPc in reflecting the MRI-PDFF response and remission of NAFLD, with all non-invasive tests performed at screening and Month 6. In addition, we will test the hypothesis that the the change in CAPc is superior to the change of in other steatosis tests results (including the original CAP, abdominal ultrasonography and steatosis scores of fatty liver index, hepatic steatosis index, NAFLD liver fat score and NAFLD ridge score) in predicting the MRI-PDFF response. The area under the receiver-operating characteristics curve of the CAPc response in predicting the MRI-PDFF response will be compared with that of the other steatosis tests using the DeLong test.