Association Between Hepatic Steatosis, Measured by Controlled Attenuation Parameter, and Fibrosis Burden in Chronic Hepatitis B

Background & aims: The interaction between chronic hepatitis B (CHB) and hepatic steatosis is poorly understood. We investigated whether measurement of controlled attenuation parameter (CAP), a non-invasive method to quantify steatosis, can assist in monitoring patients with CHB.

Methods: We performed transient elastography, to measure liver stiffness, and made CAP measurements in 1606 patients with CHB (898 treated with nucleoside analogues, for a median 75.4 months) in Hong Kong, from January 2015 through September 2016. We also collected information on patients' medical history, current treatment, and smoking and alcohol habits, anthropometric measurements. We obtained and analyzed fasting blood samples. Severe liver fibrosis was defined, according to guidelines, as a liver stiffness measurement greater than 9.0 kPa in patients with normal level of alanine aminotransferase (ALT) or greater than 12.0 kPa in patients with a level of ALT 1-5-fold the upper limit of normal. Steatosis was defined as a CAP measurement of 248 dB/m or more, and severe steatosis as a CAP measurement or 280 dB/m more. We performed multivariate analysis to identify factors associated with severe fibrosis.

Results: The prevalence of steatosis, severe steatosis, and severe fibrosis in our cohort were 40.8%, 22.6%, and 14.1%, respectively. A higher proportion of patients with severe steatosis had severe fibrosis (21.4% vs 11.9% in the overall cohort; P < .001). In multivariate analysis, severe steatosis was associated with severe fibrosis in treatment-naïve patients (odds ratio, 3.60, 95% CI, 1.21-10.75) and in patients receiving treatment (odds ratios: 1.95 [1.06-3.61] for 3 or more years of treatment, 2.28 [1.13-4.61] for 5 or more years of treatment, and 2.79 [1.17-6.62] for 7 or more years of treatment). With every increase in CAP value of 10 dB/m, the risk of severe fibrosis increased by 15% in treatment-naïve patients and by 7%-8% in patients receiving treatment.

Conclusions: Severe steatosis, determined by CAP measurement, is associated with severe fibrosis in treatment-naïve patients with CHB and in patients receiving treatment. Longitudinal studies are required to investigate if steatosis control, in addition to antiviral treatment, can reduce the burden fibrosis in patients with CHB.