Association between anthropometric parameters and measurements of liver stiffness by transient elastography.

Background & Aims: We investigated the association between anthropometric parameters and results of liver stiffness measurements (LSMs) by transient elastography in healthy subjects and patients with nonalcoholic fatty liver disease (NAFLD).

Methods: We analyzed anthropometric and LSM data from 658 healthy subjects (37% male; mean age, 47 ± 11 years; body mass index [BMI], 21.8 ± 3.0 kg/m(2); LSM, 4.4 ± 1.6 kPa) and 247 patients with biopsy-proven NAFLD (50% male; mean age, 48 ± 11 years; BMI, 28.6 ± 6.5 kg/m(2); LSM, 9.6 ± 8.7 kPa). Healthy subjects were defined as individuals without viral hepatitis, alcoholic liver disease, or NAFLD. We investigated associations between anthropometric parameters, including BMI and waist circumference, and LSM.

Results: LSMs were slightly higher among healthy subjects with BMIs ≤ 18.5 kg/m(2) (n = 84, 4.8 ± 1.5 kPa) and BMIs of 25-29.9 kg/m(2) (n = 76, 5.3 ± 2.2 kPa) than those with BMIs of 18.5-24.9 kg/m(2) (n = 492, 4.5 ± 1.9 kPa; P = .16 by analysis of variance). Among patients with NAFLD of Brunt fibrosis stage 0 or 1, LSMs were lowest among those with BMIs of 18.5-24.9 kg/m(2) (stage 0: n = 34, 5.5 ± 2.2 kPa; stage 1: n = 18, 7.2 ± 3.8 kPa). LSMs were higher among those with BMIs of 25-29.9 kg/m(2) (stage 0: n = 41, 6.1 ± 1.3 kPa; stage 1: n = 26, 7.9 ± 3.5 kPa) and highest for those with BMIs ≥30 kg/m(2) (stage 0: n = 13, 8.5 ± 2.2 kPa; stage 1: n = 22, 11.7 ± 5.2 kPa) (P < .001 and P = .002, respectively, by analysis of variance). High BMI was independently associated with high LSM, in addition to fibrosis stage, among patients with NAFLD. Patients with different waist circumferences had comparable LSMs.

Conclusions: BMI ≥30 kg/m(2) is associated with higher LSMs in patients with NAFLD, after adjusting for fibrosis stage.