Jeffrey Cui

Magnetic resonance elastography is superior to acoustic radiation force impulse for the Diagnosis of fibrosis in patients with biopsy‐proven nonalcoholic fatty liver disease: A prospective study

Magnetic resonance elastography (MRE), an advanced magnetic resonance–based imaging technique, and acoustic radiation force impulse (ARFI), an ultrasound‐based imaging technique, are accurate for diagnosing nonalcoholic fatty liver disease (NAFLD) fibrosis. However, no head‐to‐head comparisons between MRE and ARFI for diagnosing NAFLD fibrosis have been performed. We compared MRE versus ARFI head‐to‐head for diagnosing fibrosis in well‐characterized patients with biopsy‐proven NAFLD. This cross‐sectional analysis of a prospective cohort involved 125 patients (54.4% female) who underwent MRE, ARFI, and contemporaneous liver biopsies scored using the Nonalcoholic Steatohepatitis Clinical Research Network histological scoring system. The performances of MRE versus ARFI for diagnosing fibrosis were evaluated using area under the receiver operating characteristic curves (AUROCs). The mean (± standard deviation) age and body mass index were 48.9 (±15.4) years and 31.8 (±7.0) kg/m2, respectively. For diagnosing any fibrosis (≥ stage 1), the MRE AUROC was 0.799 (95% confidence interval [CI] 0.723‐0.875), significantly (P = 0.012) higher than the ARFI AUROC of 0.664 (95% CI 0.568‐0.760). In stratified analysis by presence or absence of obesity, MRE was superior to ARFI for diagnosing any fibrosis in obese patients (P < 0.001) but not in nonobese patients (P = 0.722). The MRE AUROCs for diagnosing ≥stages 2, 3, and 4 fibrosis were 0.885 (95% CI 0.816‐0.953), 0.934 (95% CI 0.863‐1.000), and 0.882 (95% CI 0.729‐1.000); and the ARFI AUROCs were 0.848 (95% CI 0.776‐0.921), 0.896 (95% CI 0.824‐0.968), and 0.862 (95% CI 0.721‐1.000). MRE had higher AUROCs than ARFI for discriminating dichotomized fibrosis stages at all dichotomization cutoff points, but the AUROC differences decreased as the cutoff points (fibrosis stages) increased. Conclusion: MRE is more accurate than ARFI for diagnosing any fibrosis in NAFLD patients, especially those who are obese. (Hepatology 2016;63:453–461)

Sitagliptin vs. placebo for non-alcoholic fatty liver disease: A randomized controlled trial

BACKGROUND & AIMS Uncontrolled studies show sitagliptin, an oral DPP-4 inhibitor, may improve alanine aminotransferase and liver histology in non-alcoholic fatty liver disease (NAFLD) patients. We aimed to compare sitagliptin vs. the efficacy of a placebo in reducing liver fat measured by MRI-derived proton density-fat fraction (MRI-PDFF). METHODS This randomized, double-blind, allocation-concealed, placebo-controlled trial included 50 NAFLD patients with prediabetes or early diabetes randomized to sitagliptin orally 100mg/day or placebo for 24weeks. Primary outcome was liver fat change measured by MRI-PDFF in colocalized regions of interest within each of nine liver segments. Additional advanced assessments included MR spectroscopy (MRS) for internal validation of MRI-PDFFs accuracy, and magnetic resonance elastography (MRE) and FIBROSpect® II to assess liver fibrosis. RESULTS Sitagliptin was not significantly better than placebo in reducing liver fat measured by MRI-PDFF (mean difference between sitagliptin and placebo arms: -1.3%, p=0.4). Compared to baseline, there were no significant differences in end-of-treatment MRI-PDFF for sitagliptin (18.1% to 16.9%, p=0.27) or placebo (16.6% to 14.0%, p=0.07). The groups had no significant differences for changes in alanine aminotransferase, aspartate aminotransferase, low-density lipoprotein, homeostatic model assessment insulin resistance, and MRE-derived liver stiffness. In both groups at baseline and post-treatment, MRI-PDFF and MRS showed robust correlation coefficients ranging from r(2)=0.96 to r(2)=0.99 (p<0.0001), demonstrating the strong internal validity of the findings. FIBROSpect® II showed no changes in the sitagliptin group but was significantly increased in the placebo group (p=0.03). CONCLUSIONS Sitagliptin was safe but not better than placebo in reducing liver fat in prediabetic or diabetic patients with NAFLD. LAY SUMMARY In a randomized, double-blind, placebo-controlled study, the anti-diabetic drug sitagliptin was no more effective than placebo for improving liver fat and liver fibrosis in patients with non-alcoholic fatty liver disease. This study demonstrates that non-invasive magnetic resonance imaging techniques, including magnetic resonance imaging-proton density-fat fraction and magnetic resonance elastography, can be used to assess treatment response in non-alcoholic fatty liver disease clinical trials.

MRE is superior to ARFI for the diagnosis of fibrosis in patients with biopsy‐proven NAFLD: A prospective study

Magnetic resonance elastography (MRE), an advanced magnetic resonance–based imaging technique, and acoustic radiation force impulse (ARFI), an ultrasound‐based imaging technique, are accurate for diagnosing nonalcoholic fatty liver disease (NAFLD) fibrosis. However, no head‐to‐head comparisons between MRE and ARFI for diagnosing NAFLD fibrosis have been performed. We compared MRE versus ARFI head‐to‐head for diagnosing fibrosis in well‐characterized patients with biopsy‐proven NAFLD. This cross‐sectional analysis of a prospective cohort involved 125 patients (54.4% female) who underwent MRE, ARFI, and contemporaneous liver biopsies scored using the Nonalcoholic Steatohepatitis Clinical Research Network histological scoring system. The performances of MRE versus ARFI for diagnosing fibrosis were evaluated using area under the receiver operating characteristic curves (AUROCs). The mean (± standard deviation) age and body mass index were 48.9 (±15.4) years and 31.8 (±7.0) kg/m2, respectively. For diagnosing any fibrosis (≥ stage 1), the MRE AUROC was 0.799 (95% confidence interval [CI] 0.723‐0.875), significantly (P = 0.012) higher than the ARFI AUROC of 0.664 (95% CI 0.568‐0.760). In stratified analysis by presence or absence of obesity, MRE was superior to ARFI for diagnosing any fibrosis in obese patients (P < 0.001) but not in nonobese patients (P = 0.722). The MRE AUROCs for diagnosing ≥stages 2, 3, and 4 fibrosis were 0.885 (95% CI 0.816‐0.953), 0.934 (95% CI 0.863‐1.000), and 0.882 (95% CI 0.729‐1.000); and the ARFI AUROCs were 0.848 (95% CI 0.776‐0.921), 0.896 (95% CI 0.824‐0.968), and 0.862 (95% CI 0.721‐1.000). MRE had higher AUROCs than ARFI for discriminating dichotomized fibrosis stages at all dichotomization cutoff points, but the AUROC differences decreased as the cutoff points (fibrosis stages) increased. Conclusion: MRE is more accurate than ARFI for diagnosing any fibrosis in NAFLD patients, especially those who are obese. (Hepatology 2016;63:453–461)

Comparative diagnostic accuracy of magnetic resonance elastography vs. eight clinical prediction rules for non‐invasive diagnosis of advanced fibrosis in biopsy‐proven non‐alcoholic fatty liver disease: a prospective study

Two‐dimensional magnetic resonance elastography (2D‐MRE) is an advanced magnetic resonance method with high diagnostic accuracy for predicting advanced fibrosis in non‐alcoholic fatty liver disease (NAFLD) patients. However, no prospective, head‐to‐head comparisons between 2D‐MRE and clinical prediction rules (CPRs) have been performed in patients with biopsy‐proven NAFLD.

Novel 3D Magnetic Resonance Elastography for the Noninvasive Diagnosis of Advanced Fibrosis in NAFLD: A Prospective Study.

OBJECTIVES:Recent studies show two-dimensional (2D)-magnetic resonance elastography (MRE) is accurate in diagnosing advanced fibrosis (stages 3 and 4) in nonalcoholic fatty liver disease (NAFLD) patients. Three-dimensional (3D)-MRE is a more advanced version of the technology that can image shear-wave fields in 3D of the entire liver. The aim of this study was to prospectively compare the diagnostic accuracy of 3D-MRE and 2D-MRE for diagnosing advanced fibrosis in patients with biopsy-proven NAFLD.METHODS:This cross-sectional analysis of a prospective study included 100 consecutive patients (56% women) with biopsy-proven NAFLD who also underwent MRE. Area under the receiver operating characteristic (AUROC) analysis was performed to assess the accuracy of 2D- and 3D-MRE in diagnosing advanced fibrosis.RESULTS:The mean (±s.d.) of age and body mass index were 50.2 (±13.6) years and 32.1 (±5.0) kg/m2, respectively. The AUROC for diagnosing advanced fibrosis was 0.981 for 3D-MRE at 40 Hz, 0.927 for 3D-MRE at 60 Hz (standard shear-wave frequency), and 0.921 for 2D-MRE at 60 Hz (standard shear-wave frequency). At a threshold of 2.43 kPa, 3D-MRE at 40 Hz had sensitivity 1.0, specificity 0.94, positive predictive value 0.72, and negative predictive value 1.0 for diagnosing advanced fibrosis. 3D-MRE at 40 Hz had significantly higher AUROC (P<0.05) than 2D-MRE at 60 Hz for diagnosing advanced fibrosis.CONCLUSIONS:Utilizing a prospective study design, we demonstrate that 3D MRE at 40 Hz has the highest diagnostic accuracy in diagnosing NAFLD advanced fibrosis. Both 2D- and 3D-MRE at 60 Hz, the standard shear-wave frequency, are also highly accurate in diagnosing NAFLD advanced fibrosis.

Association of noninvasive quantitative decline in liver fat content on MRI with histologic response in nonalcoholic steatohepatitis

Background: Magnetic resonance imaging-estimated proton-density-fat-fraction (MRI-PDFF) has been shown to be a noninvasive, accurate and reproducible imaging-based biomarker for assessing steatosis and treatment response in nonalcoholic steatohepatitis (NASH) clinical trials. However, there are no data on the magnitude of MRI-PDFF reduction corresponding to histologic response in the setting of a NASH clinical trial. The aim of this study was to quantitatively compare the magnitude of MRI-PDFF reduction between histologic responders versus histologic nonresponders in NASH patients. Methods: This study is a secondary analysis of the MOZART trial, which included 50 patients with biopsy-proven NASH randomized to ezetimibe 10 mg/day orally or placebo for 24 weeks. The primary aim was to perform a head-to-head comparative analysis of histologic responders [defined as a ⩾2-point reduction in the nonalcoholic fatty liver disease (NAFLD) Activity Score (NAS) without worsening fibrosis] versus nonresponders, and the corresponding quantitative change in liver fat content measured via MRI-PDFF. Results: Of the 35 patients who underwent paired liver biopsy and MRI-PDFF assessment at the beginning and end of treatment, 10 demonstrated a histologic response. Compared with histologic nonresponders, histologic responders had a statistically significant reduction in MRI-PDFF of −4.1% ± 4.9 versus −0.6 ± 4.1 (p < 0.04) with a mean relative percent change of −29.3% ± 33.0 versus +2.0% ± 24.0 (p < 0.004), respectively. Conclusions: Utilizing paired MRI-PDFF and liver histology data, we demonstrate that a relative reduction of 29% in liver fat on MRI-PDFF is associated with a histologic response in NASH. After external validation by independent research groups, these results can be incorporated into designing future NASH clinical trials, especially those utilizing change in hepatic fat quantified by MRI-PDFF, as a treatment endpoint.

Shared genetic effects between hepatic steatosis and fibrosis: A prospective twin study

Nonalcoholic fatty liver disease is associated with metabolic risk factors including hypertension and dyslipidemia and may progress to liver fibrosis. Studies have shown that hepatic steatosis and fibrosis are heritable, but whether they have a significant shared gene effect is unknown. This study examined the shared gene effects between hepatic steatosis and fibrosis and their associations with metabolic risk factors. This was a cross‐sectional analysis of a prospective cohort of well‐characterized, community‐dwelling twins (45 monozygotic, 20 dizygotic twin pairs, 130 total subjects) from southern California. Hepatic steatosis was assessed with magnetic resonance imaging‐proton density fat fraction and hepatic fibrosis with magnetic resonance elastography. A standard bivariate twin additive genetics and unique environment effects model was used to estimate the proportion of phenotypic variance between two phenotypes accounted for by additive genetic effects and individual‐specific environmental effects. Genetic correlations estimated from this model represent the degree to which the genetic determinants of two phenotypes overlap. Mean (± standard deviation) age and body mass index were 47.1 (±21.9) years and 26.2 (±5.8) kg/m2, respectively. Among the cohort, 20% (26/130) had hepatic steatosis (magnetic resonance imaging‐proton density fat fraction ≥5%), and 8.2% (10/122) had hepatic fibrosis (magnetic resonance elastography ≥3 kPa). Blood pressure (systolic and diastolic), triglycerides, glucose, homeostatic model assessment of insulin resistance, insulin, hemoglobin A1c, and low high‐density lipoprotein had significant shared gene effects with hepatic steatosis. Triglycerides, glucose, homeostatic model assessment of insulin resistance, insulin, hemoglobin A1c, and low high‐density lipoprotein had significant shared gene effects with hepatic fibrosis. Hepatic steatosis and fibrosis had a highly significant shared gene effect of 0.756 (95% confidence interval 0.716‐1, P < 0.0001). Conclusions: Genes involved with steatosis pathogenesis may also be involved with fibrosis pathogenesis. (Hepatology 2016;64:1547‐1558)

Nonalcoholic fatty liver disease with cirrhosis increases familial risk for advanced fibrosis

BACKGROUND. The risk of advanced fibrosis in first-degree relatives of patients with nonalcoholic fatty liver disease and cirrhosis (NAFLD-cirrhosis) is unknown and needs to be systematically quantified. We aimed to prospectively assess the risk of advanced fibrosis in first-degree relatives of probands with NAFLD-cirrhosis. METHODS. This is a cross-sectional analysis of a prospective cohort of 26 probands with NAFLD-cirrhosis and 39 first-degree relatives. The control population included 69 community-dwelling twin, sib-sib, or parent-offspring pairs (n = 138), comprising 69 individuals randomly ascertained to be without evidence of NAFLD and 69 of their first-degree relatives. The primary outcome was presence of advanced fibrosis (stage 3 or 4 fibrosis). NAFLD was assessed clinically and quantified by MRI proton density fat fraction (MRI-PDFF). Advanced fibrosis was diagnosed by liver stiffness greater than 3.63 kPa using magnetic resonance elastography (MRE). RESULTS. The prevalence of advanced fibrosis in first-degree relatives of probands with NAFLD-cirrhosis was significantly higher than that in the control population (17.9% vs. 1.4%, P = 0.0032). Compared with controls, the odds of advanced fibrosis among the first-degree relatives of probands with NAFLD-cirrhosis were odds ratio 14.9 (95% CI, 1.8–126.0, P = 0.0133). Even after multivariable adjustment by age, sex, Hispanic ethnicity, BMI, and diabetes status, the risk of advanced fibrosis remained both statistically and clinically significant (multivariable-adjusted odds ratio 12.5; 95% CI, 1.1–146.1, P = 0.0438). CONCLUSION. Using a well-phenotyped familial cohort, we demonstrated that first-degree relatives of probands with NAFLD-cirrhosis have a 12 times higher risk of advanced fibrosis. Advanced fibrosis screening may be considered in first-degree relatives of NAFLD-cirrhosis patients. TRIAL REGISTRATION. UCSD IRB: 140084. FUNDING. National Institute of Diabetes and Digestive and Kidney Diseases and National Institute of Environmental Health Sciences, NIH.

947 Shared Genetic Effects Between Hepatic Steatosis and Fibrosis: A Prospective Twin Study

Author(s): Cui, J; Chen, CH; Lo, MT; Schork, N; Bettencourt, R; Gonzalez, MP; Bhatt, A; Hooker, J; Shaffer, K; Nelson, KE; Long, MT; Brenner, DA; Sirlin, CB; Loomba, R | Abstract:

Response to Letter to Editors: Magnetic resonance elastography: Better but still the same!

M, et al. Magnetic resonance elastography predicts advanced fibrosis in patients with nonalcoholic fatty liver disease: a prospective study. HEPATOLOGY 2014;60:1920-1928. 3) Imajo K, Kessoku T, Honda Y, Tomeno W, Ogawa Y, Mawatari H, et al. Magnetic resonance imaging more accurately classifies steatosis and fibrosis in patients with nonalcoholic fatty liver disease than transient elastography. Gastroenterology 2016;150:626637.