Association between pancreatic ectopic fat deposition and QCT-assessed bone mass status in patients with chronic kidney disease: a cross-sectional study

Figures

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  Figure 1.. Flowchart of patient selection.

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  Figure 2.. Representative images of QCT-based body composition analysis and fat quantification. (A, B) Body composition analysis at the level of the third lumbar vertebra (L3). (A) Automatic segmentation based on predefined CT attenuation thresholds, including the abdominal wall, paraspinal, and psoas muscles and intra-abdominal contents; (B) manual delineation of the intra-abdominal region. The L3 skeletal muscle area (L3-SMA) was obtained by subtracting the intra-abdominal region from the automatically segmented region. (C) Measurement of liver fat fraction. ROIs were placed in the left lobe, right anterior lobe, and right posterior lobe of the liver, and the fat fractions from the three ROIs were averaged to obtain the mean liver fat fraction. (D–F) Measurement of pancreatic fat fraction. ROIs were placed in the pancreatic head (D), body (E), and tail (F), and the fat fractions from the three regions were averaged to obtain the mean pancreatic fat fraction.

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  Figure 3.. Restricted cubic spline (RCS) analysis of the association between mean pancreatic fat fraction and bone mass status. RCS analysis was performed to evaluate the dose–response relationship between mean pancreatic fat fraction and the odds of being in a more severe bone mass category. The model was adjusted for age, sex, BMI, eGFR, diabetes mellitus, hypertension, and L3-SMI, with four knots used for the spline function. The solid line represents the adjusted OR, the shaded area represents the 95% CI, and the horizontal dashed line indicates an OR of 1. The model was fitted using data from all 327 patients. For visualization purposes, the x-axis displays the 1st–99th percentile range of mean pancreatic fat fraction.

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  Figure 4.. Subgroup analysis of the association between mean pancreatic fat fraction and the odds of being in a more severe bone mass category. Subgroup analyses were performed according to sex, age, diabetes status, and CKD stage. The points represent adjusted ORs for the odds of being in a more severe bone mass category associated with each 5-percentage-point increase in mean pancreatic fat fraction, and the horizontal lines represent 95% CIs. All subgroup models were adjusted for age, sex, BMI, eGFR, diabetes mellitus, hypertension, and L3-SMI, except for the corresponding stratification variable. In the CKD stage subgroup analysis, eGFR was not additionally adjusted. The vertical dashed line indicates an OR of 1. P for interaction was used to assess potential effect modification by each stratification factor.