Transient elastographic evaluation in adult subjects without overt liver disease: influence of alanine aminotransferase levels

Abstract

Background and aim: Studies on normal values of liver stiffness (LS) in subjects at "low risk" for liver disease are scant. The aim of the present study was to assess liver stiffness values in the subjects without overt liver disease with normal alanine aminotransferases (ALT) and to determine potential factors, which may influence these values with special reference to newly suggested updated upper limits of normal for ALT.

Methods: Liver stiffness measurements were performed in 445 subjects without overt liver disease (mean age, 41.1±13.6; male, 73.5%) and normal liver enzymes.

Results: Mean LS value was 5.10±1.19kPa. LS values were higher in men than in women (5.18±1.67 vs 4.86±1.24kPa, respectively, P=0.008); in subjects with higher body mass index (BMI) category (Normal, overweight and obese subjects; 4.10±0.75, 5.08±0.66, and 6.05±1.28kPa, respectively; P<0.001); in subjects with metabolic syndrome than in those without (5.63±1.37 vs 5.01±1.14kPa, P=0.001); and in subjects with ALT levels more than updated limits of normal compared to subjects with ALT levels less than updated limits of normal (5.68±1.21 vs 4.77±1.05kPa, P<0.001). On multiple linear regression, BMI and ALT was found to be significant predictor of LS.

Conclusions: Liver stiffness values in subjects without overt liver disease with normal ALT are influenced by BMI and ALT levels. Subjects with ALT levels less than updated limits of normal have lower LS values as compared to those with higher levels.