Prevalence of Elevated Liver Stiffness Among Potential Candidates for Bariatric Surgery in the United States

Purpose: Obesity represents a well-known risk factor for metabolic-dysfunction associated fatty liver disease (MAFLD) and its progression towards cirrhosis. The aim of this study is to estimate the proportion of potential candidates to a bariatric surgery intervention that has an elevated liver stiffness on vibration-controlled transient elastography (VCTE).

Materials and methods: This is a cross-sectional study performed using data obtained during the 2017-2018 cycle of the National Health and Nutrition Examination Survey. Potential candidates for a bariatric surgery intervention from the general US population were identified by applying criteria from international guidelines. All included participants were evaluated by VCTE. A controlled attenuation parameter (CAP) value ≥ 288 dB/m was considered indicative of steatosis while liver stiffness measurement (LSM) was considered elevated if ≥ 9.7 kPa. Multivariable logistic regression models were fitted to identify independent predictors of both outcomes.

Results: A total of 434 participants were included (mean age 42.9 ± 0.6 years; 54.4% women). Among them, 76.7% (95% CI 71.7-81.0) had steatosis, while 23.1% (95% CI 17.8-29.3) had an elevated LSM. Male sex, older age, γ-glutamyltranspeptidase levels, and body mass index (BMI) were independent predictors of steatosis, while BMI was the only independent predictor of elevated LSM. Non-Hispanic black participants were protected from both outcomes, while other ethnicities were not.

Conclusion: The prevalence of elevated LSM is high in potential candidates for a bariatric surgery intervention. Accurate screening for occult advanced liver disease might be indicated in this patient population.