Spleen stiffness measurement by vibration-controlled transient elastography at 100 Hz for non-invasive predicted diagnosis of clinically significant portal hypertension in patients with compensated advanced chronic liver disease: a modelling study

Abstract

Background: In patients with compensated advanced chronic liver disease (cACLD), risk of clinically significant portal hypertension (CSPH) can be estimated by applying non-invasive tests such as liver stiffness measurement (LSM), platelet count, and, in some cases, BMI. We aimed to assess the diagnostic utility of spleen stiffness measurement (SSM) at 100 Hz as a standalone non-invasive test for CSPH and to evaluate its incremental value compared with the ANTICIPATE±NASH model in patients with cACLD.

Methods: For this modelling study, patients were recruited from 16 expert centres in Europe. Patients who underwent characterisation by hepatic venous pressure gradient (HVPG) and non-invasive tests (ie, LSM, platelet count, and SSM at 100 Hz) at one of the participating centres between Jan 1, 2020, and Dec 31, 2023, were considered for inclusion. Only patients aged 18 years or older with Child-Pugh class A cACLD, shown by LSM 10 kPa or more or F3 or F4 fibrosis on liver histology, were included. The overall cohort was split into the derivation cohort (patients recruited between Jan 1, 2020, and Dec 31, 2022) and the temporal validation cohort (patients recruited between Jan 1, 2023, and Dec 31, 2023). The ANTICIPATE±NASH model was applied to assess individual CSPH probability and SSM was investigated as a standalone non-invasive test for CPSH; in combination with platelet count and BMI; and in a full model of SSM, LSM, platelet count, and BMI (ie, the Non-Invasive CSPH Estimated Risk [NICER] model). All models were binary logistic regression models. The primary outcome was CSPH. We evaluated the discriminative utility of the models by calculating the area under the receiver operating characteristics curve (AUC) and creating calibration plots and calibration of intercept, slope, and integrated calibration index.

Findings: 407 patients with cACLD were included, 202 (50%) in the derivation cohort and 205 (50%) in the validation cohort. Median age was 60·0 years (IQR 55·0-66·8); 275 (68%) of 407 patients were male and 132 (32%) were female. 164 (40%) of 407 patients had metabolic dysfunction-associated steatotic liver disease (MASLD), 133 (33%) had MASLD with increased alcohol intake or alcohol-related liver disease, 75 (18%) had viral hepatitis (61 [81%] of whom had sustained virologic response of hepatitis C virus or suppression of hepatitis B virus DNA), and 35 (9%) had other chronic liver diseases. 241 (59%) patients had CSPH. Median SSM was 45·0 kPa (32·1-65·4) and LSM was 21·4 kPa (14·1-31·6). SSM and LSM had similar AUCs for prediction of CSPH in the derivation cohort (0·779 [95% CI 0·717-0·842] vs 0·781 [0·718-0·844]; p=0·97) and in the validation cohort (0·830 [0·772-0·887] vs 0·804 [0·743-0·864]; p=0·50). The SSM-based model comprising platelet count and BMI had a similar AUC as the ANTICIPATE±NASH model in both the derivation cohort (0·849 [0·794-0·903] vs 0·849 [0·794-0·903]; p=0·999) and in the validation cohort (0·873 [0·819-0·922] vs 0·863 [0·810-0·916]; p=0·75). The NICER model had a significantly higher AUC for prediction of CSPH than the ANTICIPATE±NASH model in the derivation cohort (0·889 [0·843-0·934] vs 0·849 [0·794-0·903]; p=0·022) and in the validation cohort (0·906 [0·864-0·946] vs 0·863 [0·810-0·916]; p=0·012).

Interpretation: The addition of SSM to LSM, BMI, and platelet count outperformed the ANTICIPATE±NASH model for CSPH risk stratification in our cohort of contemporary patients with cACLD. SSM improves the non-invasive diagnosis of CSPH, supporting its implementation into clinical practice.

Funding: Echosens.