Non-invasive estimation of liver fibrosis in non-alcoholic fatty liver disease using the 13C-caffeine breath test

Background and Aim: Fibrotic progression in non‐alcoholic fatty liver disease (NAFLD) is associated with impaired hepatic function. The 13C‐caffeine breath test (CBT) is a non‐invasive, quantitative test of liver function. We sought to determine the utility of the CBT in detecting hepatic fibrosis in NAFLD. Methods: The CBT was applied to 48 patients with NAFLD. CBT results were compared to clinical, biochemical and histological data. Twenty‐four healthy subjects served as controls. Results: Patients with simple steatosis had similar CBT values (2.28 ± 0.71 Δ‰ per 100 mg caffeine) to controls (2.31 ± 0.85, P = 1.0). However, CBT was significantly reduced in patients with non‐alcoholic steatohepatitis (1.59 ± 0.65, P = 0.005) and cirrhosis (1.00 ± 0.73, P