Impact of anthropometric features on the applicability and accuracy of FibroScan (M and XL) in overweight/obese patients.

BACKGROUND AND AIM

Transient elastography is the reference method for liver stiffness measurement (LSM) in the general population, having lower applicability in obese patients. We evaluated the applicability and diagnostic accuracy of the M and XL probes in overweight/obese patients to establish the most appropriate approach.

METHODS

From May 2013 to March 2015, we evaluated patients with a body mass index (BMI) ≥ 28 kg/m . We constructed an algorithm with variables independently related to unreliable LSM with the M probe.

RESULTS

A total of 1084 patients were evaluated. M and XL probe applicability was 88.8% and 98%, respectively. Waist circumference (WC) (OR; 95% CI; P) (0.97; 0.94-0.99; P < 0.001) and skin-capsule distance (SCD) (0.83; 0.79-0.87; P < 0.001) were independently related to unreliable LSM (M probe). The SCD was > 25 mm in 5.5% of individuals with a BMI ≤ 35 kg/m and a WC ≤ 117 cm, with LSM (M probe) applicability rising to 94.3%. In contrast, 36.9% of patients with a BMI > 35 kg/m and/or a WC > 117 cm presented an SCD > 25 mm, with M probe applicability being 73.1%. The diagnostic accuracy (area under the receiver operator characteristic) using the M probe to identify significant steatosis (0.76), fibrosis (0.89), and cirrhosis (0.96) was very high in patients with a BMI ≤ 35 kg/m and a WC ≤ 117 cm.

CONCLUSIONS

The applicability and accuracy of the FibroScan M probe to identify fibrosis and steatosis was excellent in overweight and obesity grade I (BMI ≤ 35 kg/m ) with a WC ≤ 117 cm. The XL probe increased the applicability of transient elastography in obesity grade II-III (BMI > 35 kg/m ).