The impact of a low-calorie, reduced-fat diet on liver attenuation imaging: a randomized clinical trial

To investigate whether a low-calorie, reduced-fat diet affects liver attenuation imaging (ATI) measurements.

A total of 320 participants were enrolled in this prospective study. They were randomly assigned to four groups: a fasting group, a postprandial 0.5-hour examination group, a postprandial 2-hour examination group, and a postprandial 4-hour examination group. All participants first underwent liver ATI examination in a fasting state. Those in the postprandial groups then consumed a low-calorie, reduced-fat diet before undergoing a second ATI examination at 0.5 h, 2 h, or 4 h after the meal. The ATI values were compared among the groups. The differences between postprandial and fasting ATI values were also analyzed for the postprandial groups. Additionally, the consistency of the grading diagnosis of hepatic steatosis between the postprandial and fasting states was evaluated in the postprandial groups.

The ATI values for the 0.5 h postprandial group, 2 h postprandial group, and 4 h postprandial group were not significantly different from those of the fasting group (P = 0.576, 0.471, and 0.992, respectively). No significant differences were noted in the ATI values recorded during the postprandial and fasting states within each of the postprandial groups (P = 0.573, 0.076, and 0.805, respectively). The kappa values for diagnostic consistency between the postprandial and fasting states across the three divergent criteria were 0.833-0.951, 0.812-0.855, and 0.737-0.862, respectively.

A low-calorie, reduced-fat diet does not significantly affect liver ATI measurements or the grading of hepatic steatosis. However, the lack of representation of older adults and populations with higher BMIs in this study may limit its generalizability, with the lack of external validation as a limitation. These issues should be tested and confirmed in further studies.

(ChiCTR2200062314, August 2022).