Factors associated with unreliable liver stiffness measurement and its failure with transient elastography in the Chinese population

Background and Aim: Liver stiffness measurement (LSM) with transient elastography is a non-invasive and reliable test for liver fibrosis. However a small proportion of patients may have unreliable LSM or LSM failure. The aim of the present study was to investigate the factors associated with unreliable LSM or LSM failure in Chinese patients. Methods: We prospectively recruited liver patients for LSM. Unreliable LSM was defined as < 10 valid shots, an interquartile range (IQR)/LSM > 30%, or a success rate < 60%. LSM failure was defined as zero valid shots. Results: Among 3205 patients with LSM, 371 (11.6%) and 88 (2.7%) had unreliable LSM and LSM failure, respectively. The rates started to increase when body mass index (BMI) >= 28.0 kg/m2. Comparing patients with BMI >= 28.0-29.9 kg/m2 versus those with BMI >= 30.0 kg/m2, the rates of unreliable LSM (16.4% vs 18.9%; P = 0.62) and LSM failure (11.8% vs 17.8%; P = 0.16) were similar. BMI >= 28.0 kg/m2 was the most important factor associated with unreliable LSM (odds ratio [OR] = 2.9, 95% confidence interval [CI] = 2.1-3.9, P < 0.0001) and LSM failure (OR = 10.1, 95% CI = 6.4-14.2, P < 0.0001). Central obesity, defined as waist circumference > 80 cm in women and > 90 cm in men, was another independent risk factor of unreliable LSM (OR = 1.3, 95% CI = 1.0-1.6, P = 0.04) and LSM failure (OR = 5.8, 95% CI = 2.9-11.5, P < 0.0001). Conclusion: BMI >= 28.0 kg/m2 and central obesity were the independent risk factors of unreliable LSM and LSM failure in Chinese, and these rates were significantly higher in patients with extreme BMI.