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BACKGROUND:Given the lack of long-term prospective studies, it is challenging for clinicians to make informed decisions about screening and treatment decisions regarding the risk of hepatocellular carcinoma (HCC) in patients with non-alcoholic steatohepatitis (NASH) who do not have cirrhosis. AIM:To characterise the pooled risk of HCC in the non-cirrhosis population. METHODS:Published studies were identified through April 2016 in MEDLINE, Scopus, Science Citation Index, AMED and the Cochrane Library. Two independent reviewers screened citations and extracted data. Random effect odds ratios (OR) were calculated to obtain aggregate estimates of effect size between NASH and non-NASH groups. Between-study variability and heterogeneity were assessed. RESULTS:Nineteen studies with 168 571 participants were included. Eighty-six per cent of included subjects had cirrhosis. The prevalence of HCC in non-cirrhotic NASH was 38.0%; among other aetiologies in non-cirrhotics, it was 14.2% (P < 0.001). Non-cirrhotic NASH subjects were at greater odds of developing HCC than non-cirrhotic subjects of other aetiologies (OR 2.61, 95% CI 1.27-5.35, P = 0.009). When examining all NASH subjects either with or without cirrhosis, those with NASH as the underlying liver disease did not have a significantly increased risk of HCC (OR 1.43, 95% CI 0.77-2.65, P = 0.250). CONCLUSIONS:In non-cirrhotic subjects, those with NASH have a higher risk of HCC compared to other aetiologies of liver disease. Further study investigating the risk factors of HCC among non-cirrhotic NASH patients is needed.

Background and aims

Exercise remains a key component of nonalcoholic fatty liver disease (NAFLD) treatment. However, mechanisms underpinning the improvements in NAFLD seen with exercise are unclear. Exercise improved liver fat and serum biomarkers of liver fibrosis in the NASHFit trial. We investigated exercise's mechanism of benefit by conducting a post hoc analysis of these data to determine the relationship between serum fibroblast growth factor (FGF) 21, which is implicated in NAFLD development, and exercise.

Methods

In the 20 wk NASHFit trial, patients with nonalcoholic steatohepatitis (NASH) were randomized to receive moderate-intensity aerobic exercise training or standard clinical care. Mediterranean-informed dietary counseling was provided to each group. Change in serum FGF21 was measured after an overnight fast.

Results

There was a significant improvement in serum FGF21 with exercise training compared to standard clinical care (p = 0.037) with serum FGF21 reducing by 22% (-243.4 +/-349 ng/mL) with exercise vs. a 34% increase (+88.4 ng/mL +/-350.3 ng/mL) with standard clinical care. There was a large inverse association between change in serum FGF21 and change in cardiorespiratory fitness (VO₂peak) (r = -0.62, 95% CI -0.88 to -0.05, p = 0.031), and on multivariable analysis, change in VO₂peak remained independently associated with change in FGF21 (β = -44.5, 95% CI -83.8 to -5.11, p = 0.031).

Conclusions

Serum FGF21 is markedly decreased in response to aerobic exercise training, offering a novel mechanism to explain the observed reduction in liver fat and improvement in serum biomarkers of liver fibrosis in patients with NASH who do exercise.

Background & aims

Magnetic resonance imaging proton density fat fraction (MRI-PDFF) offers promise as a non-invasive biomarker of treatment response in early-phase nonalcoholic steatohepatitis (NASH) trials. We performed a systematic review to quantify the association between a ≥ 30% reduction in MRI-PDFF and histologic response in NASH.

Methods

We searched the Cochrane Library, Embase, Medline and trial registries through May 2020 for early-phase clinical trials that incorporated MRI-PDFF and examined histologic response following intervention in adults with NASH. Subjects were classified as MRI-PDFF responders (relative decline in liver fat ≥30%) or non-responders (relative decline in liver fat <30%). MRI-PDFF responders versus non-responders were compared. Primary outcome was histologic response defined as a 2-point improvement in NAFLD Activity Score with at least 1-point improvement in lobular inflammation or ballooning. Secondary outcome was NASH resolution. Proportions and random effects odds ratios (OR) with corresponding 95% confidence intervals (CI) were calculated.

Results

Seven studies met inclusion criteria, comprising 346 subjects (median age 51 years; 59% female; 46% with diabetes). MRI-PDFF responders were significantly more likely to have a histologic response (51% vs 14%, P < .001; OR 6.98, 95% CI 2.38-20.43, P < .001) and NASH resolution (41% vs 7%, P < .001; OR 5.45, 95% CI 1.53-19.46, P = .009) compared to non-responders.

Conclusions

This meta-analysis demonstrates that a ≥30% relative decline in MRI-PDFF is associated with higher odds of histologic response and NASH resolution. These results support the use of MRI-PDFF in non-invasive monitoring of treatment response in early-phase NASH clinical trials and provide helpful data for sample-size estimation for histology-based assessment.

Background and aims

NASH is a common disease associated with increased rates of thromboembolism (TE). Although exercise training can lessen thrombotic risk in patients with vascular disease, whether similar findings are observed in patients with NASH is open for study.

Approach and results

We conducted a 20-week randomized controlled clinical trial involving patients with biopsy-confirmed NASH. Patients were randomly assigned (2:1 ratio) to receive either an exercise training program or standard clinical care. The primary endpoint was change in plasminogen activator inhibitor 1 (PAI-1) level, an established thrombotic biomarker. Twenty-eight patients were randomly assigned (18 exercise training and 10 standard clinical care). PAI-1 level was significantly decreased by exercise training when compared to standard clinical care (-40 ± 100 vs. +70 ± 63 ng/ml; p = 0.02). Exercise training decreased MRI proton density fat fraction (MRI-PDFF; -4.7 ± 5.6 vs. 1.2 ± 2.8% absolute liver fat; p = 0.01); 40% of exercise subjects had a ≥30% relative reduction in MRI-PDFF (histological response threshold) compared to 13% for standard of care (p < 0.01). Exercise training improved fitness (VO₂ peak, +3.0 ± 5.6 vs. -1.8 ± 5.1 ml/kg/min; p = 0.05) in comparison to standard clinical care.

Conclusions

This clinical trial showed that, independent of weight loss or dietary change, exercise training resulted in a significantly greater decrease in thrombotic risk than standard clinical care in patients with NASH, in parallel with MRI-PDFF reduction and improvement in fitness. Future studies are required to determine whether exercise training can directly impact patient outcomes and lower rates of TE.

Nonalcoholic fatty liver disease is the leading cause of liver disease worldwide and can progress to nonalcoholic steatohepatitis (NASH) through physical inactivity and gut dysbiosis.¹ Exercise training reverses gut dysbiosis in non-NASH persons with obesity and in NASH animal models.^2,3 Consequently, we conducted a proof-of-concept study investigating the effect of exercise training on gut dysbiosis in NASH patients.