Biomarkers and subtypes of deranged lipid metabolism in non-alcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is a heterogeneous and complex disease that is imprecisely diagnosed by liver biopsy. NAFLD covers a spectrum that ranges from simple steatosis, nonalcoholic steatohepatitis (NASH) with varying degrees of fibrosis, to cirrhosis, which is a major risk factor for hepatocellular carcinoma. Lifestyle and eating habit changes during the last century have made NAFLD the most common liver disease linked to obesity, type 2 diabetes mellitus and dyslipidemia, with a global prevalence of 25%. NAFLD arises when the uptake of fatty acids (FA) and triglycerides (TG) from circulation and de novo lipogenesis saturate the rate of FA β-oxidation and very-low density lipoprotein (VLDL)-TG export. Deranged lipid metabolism is also associated with NAFLD progression from steatosis to NASH, and therefore, alterations in liver and serum lipidomic signatures are good indicators of the disease's development and progression. This review focuses on the importance of the classification of NAFLD patients into different subtypes, corresponding to the main alteration(s) in the major pathways that regulate FA homeostasis leading, in each case, to the initiation and progression of NASH. This concept also supports the targeted intervention as a key approach to maximize therapeutic efficacy and opens the door to the development of precise NASH treatments

Metabolic subtypes of patients with NAFLD exhibit distinctive cardiovascular risk profiles

Background and Aims We previously identified subsets of patients with NAFLD with different metabolic phenotypes. Here we align metabolomic signatures with cardiovascular disease (CVD) and genetic risk factors. Approach and Results We analyzed serum metabolome from 1154 individuals with biopsy-proven NAFLD, and from four mouse models of NAFLD with impaired VLDL-triglyceride (TG) secretion, and one with normal VLDL-TG secretion. We identified three metabolic subtypes: A (47%), B (27%), and C (26%). Subtype A phenocopied the metabolome of mice with impaired VLDL-TG secretion; subtype C phenocopied the metabolome of mice with normal VLDL-TG; and subtype B showed an intermediate signature. The percent of patients with NASH and fibrosis was comparable among subtypes, although subtypes B and C exhibited higher liver enzymes. Serum VLDL-TG levels and secretion rate were lower among subtype A compared with subtypes B and C. Subtype A VLDL-TG and VLDL–apolipoprotein B concentrations were independent of steatosis, whereas subtypes B and C showed an association with these parameters. Serum TG, cholesterol, VLDL, small dense LDL5,6, and remnant lipoprotein cholesterol were lower among subtype A compared with subtypes B and C. The 10-year high risk of CVD, measured with the Framingham risk score, and the frequency of patatin-like phospholipase domain-containing protein 3 NAFLD risk allele were lower in subtype A. Conclusions Metabolomic signatures identify three NAFLD subgroups, independent of histological disease severity. These signatures align with known CVD and genetic risk factors, with subtype A exhibiting a lower CVD risk profile. This may account for the variation in hepatic versus cardiovascular outcomes, offering clinically relevant risk stratificatio

Characterization of patients with both alcoholic and nonalcoholic fatty liver disease in a large United States cohort.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome (MetS) and is characterized by steatosis in the absence of significant alcohol consumption. However, MetS and significant alcohol intake coexist in certain individuals which may lead to the development of BAFLD. AIM: To assess the clinical characteristics of patients with both alcoholic and NAFLD (BAFLD) in a large cohort in the United States. METHODS: Adults from the National Health and Nutrition Examination Survey between 2003-2014 were included. NAFLD was diagnosed based on elevated alanine aminotransferase (ALT) and being overweight or obese in the absence of other liver diseases. BAFLD patients met the criteria for NAFLD but also had either MetS or type 2 diabetes and consumed excessive amounts of alcohol. Univariable and multivariable analysis were performed to assess differences between NAFLD and BAFLD and to compare severity based on a validated fibrosis score (FIB4 index). RESULTS: The prevalence of NAFLD was at 25.9% (95%CI; 25.1-26.8) and that of BAFLD was 0.84% (0.67, 1.02) which corresponds to an estimated 1.24 million Americans affected by BAFLD. Compared to NAFLD, patients with BAFLD were more likely to be male, smokers, have higher ALT, aspartate aminotransferase, triglycerides, and lower platelets; CONCLUSION: A significant percentage of the American general population is afflicted by BAFLD and these patients tend to have more advanced liver fibrosis

Association of State Medicaid Expansion With Racial/Ethnic Disparities in Liver Transplant Wait-listing in the United States

Importance Millions of Americans gained insurance through the state expansion of Medicaid, but several states with large populations of racial/ethnic minorities did not expand their programs. Objective To investigate the implications of Medicaid expansion for liver transplant (LT) wait-listing trends for racial/ethnic minorities. Design, Setting, and Participants A cohort study was performed of adults wait-listed for LT using the United Network of Organ Sharing database between January 1, 2010, and December 31, 2017. Poisson regression and a controlled, interrupted time series analysis were used to model trends in wait-listing rates by race/ethnicity. The setting was LT centers in the United States. Main Outcomes and Measures (1) Wait-listing rates by race/ethnicity in states that expanded Medicaid (expansion states) compared with those that did not (nonexpansion states) and (2) actual vs predicted rates of LT wait-listing by race/ethnicity after Medicaid expansion. Results There were 75 748 patients (median age, 57.0 [interquartile range, 50.0-62.0] years; 48 566 [64.1%] male) wait-listed for LT during the study period. The cohort was 8.9% Black and 16.4% Hispanic. Black patients and Hispanic patients were statistically significantly more likely to be wait-listed in expansion states than in nonexpansion states (incidence rate ratio [IRR], 1.54 [95% CI, 1.44-1.64] for Black patients and 1.21 [95% CI, 1.15-1.28] for Hispanic patients). After Medicaid expansion, there was a decrease in the wait-listing rate of Black patients in expansion states (annual percentage change [APC], −4.4%; 95% CI, −8.2% to −0.6%) but not in nonexpansion states (APC, 0.5%; 95% CI, −4.0% to 5.2%). This decrease was not seen when Black patients with hepatitis C virus (HCV) were excluded from the analysis (APC, 3.1%; 95% CI, −2.4% to 8.9%), suggesting that they may be responsible for this expansion state trend. Hispanic Medicaid patients without HCV were statistically significantly more likely to be wait-listed in the post–Medicaid expansion era than would have been predicted without Medicaid expansion (APC, 13.2%; 95% CI, 4.0%-23.2%). Conclusions and Relevance This cohort study found that LT wait-listing rates have decreased for Black patients with HCV in states that expanded Medicaid. Conversely, wait-listing rates have increased for Hispanic patients without HCV. Black patients and Hispanic patients may have benefited differently from Medicaid expansion

Factors associated with unrecognized cirrhosis in patients with hepatocellular carcinoma

Background/Aims Cirrhosis is the most important risk factor of hepatocellular carcinoma (HCC), and patients with cirrhosis are recommended to receive semiannual surveillance for early HCC detection. However, early cirrhosis is often asymptomatic and can go undiagnosed for years, leading to underuse of HCC surveillance in clinical practice. We characterized the frequency and associated factors of unrecognized cirrhosis in a national sample of patients with HCC from the United States. Methods HCC patients aged 68 years and older, diagnosed during 2011 to 2015 were included from the SEER-Medicare Linked Database. If cirrhosis was diagnosed within 6 months immediately preceding HCC diagnosis or after HCC diagnosis, cases were categorized as unrecognized cirrhosis. Factors associated with unrecognized cirrhosis were identified using logistic regression analyses. Factors associated with overall survival were evaluated using Cox regression analyses. Results Among 5,098 HCC patients, 74.8% patients had cirrhosis. Among those with cirrhosis, 57.4% had unrecognized cirrhosis, with the highest proportion (76.3%) among those with NAFLD-related HCC. Male sex (aOR: 2.12, 95% CI: 1.83–2.46), non-Hispanic Black race (aOR: 1.93, 95% CI: 1.45–2.57), and NAFLD etiology (aOR: 4.46, 95% CI: 3.68–5.41) were associated with having unrecognized cirrhosis. Among NAFLD-related HCC patients, male sex (aOR: 2.32, 95% CI: 1.71–3.14) was associated with unrecognized cirrhosis. Unrecognized cirrhosis was independently associated with worse overall survival (aHR: 1.17, 95% CI: 1.08–1.27) compared to recognized cirrhosis. Conclusions Unrecognized cirrhosis is common in NAFLD-related HCC, particularly among male and Black patients, highlighting these groups as important intervention targets to improve HCC surveillance uptake and outcomes

Metabolomic-Based Noninvasive Serum Test to Diagnose Nonalcoholic Steatohepatitis: Results From Discovery and Validation Cohorts

Nonalcoholic fatty liver disease (NAFLD) is the most common type of chronic liver disease worldwide and includes a broad spectrum of histologic phenotypes, ranging from simple hepatic steatosis or nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH). While liver biopsy is the reference gold standard for NAFLD diagnosis and staging, it has limitations due to its sampling variability, invasive nature, and high cost. Thus, there is a need for noninvasive biomarkers that are robust, reliable, and cost effective. In this study, we measured 540 lipids and amino acids in serum samples from biopsy-proven subjects with normal liver (NL), NAFL, and NASH. Using logistic regression analysis, we identified two panels of triglycerides that could first discriminate between NAFLD and NL and second between NASH and NAFL. These noninvasive tests were compared to blinded histology as a reference standard. We performed these tests in an original cohort of 467 patients with NAFLD (90 NL, 246 NAFL, and 131 NASH) that was subsequently validated in a separate cohort of 192 patients (7 NL, 109 NAFL, 76 NASH). The diagnostic performances of the validated tests showed an area under the receiver operating characteristic curve, sensitivity, and specificity of 0.88 +/- 0.05, 0.94, and 0.57, respectively, for the discrimination between NAFLD and NL and 0.79 +/- 0.04, 0.70, and 0.81, respectively, for the discrimination between NASH and NAFL. When the analysis was performed excluding patients with glucose levels >136 mg/dL, the area under the receiver operating characteristic curve for the discrimination between NASH and NAFL increased to 0.81 +/- 0.04 with sensitivity and specificity of 0.73 and 0.80, respectively. Conclusion: The assessed noninvasive lipidomic serum tests distinguish between NAFLD and NL and between NASH and NAFL with high accuracy.Supported by the National Institutes of Health Blueprint for Neuroscience Research (R01AT001576 to S.C.L., J.M.M.), Agencia Estatal de Investigacion of the Ministerio de Economia, Industria y Competitividad (SAF2014-52097R to J.M.M.), CIBER Hepatic and Digestive Diseases and Instituto de Salud Carlos III (PIE14/0003 to J.M.M.), Etorgai 2015-Gobierno Vasco (ER-2015/00015 to R.M., I.M.A., C.A., A.C.), Plan de Promocion de la Innovacion 2015-Diputacion Foral de Bizkaia (6/12/IN/2015/00131 to A.C., C.A.), National Institute of Diabetes and Digestive and Kidney Diseases (RO1DK81410 to A.J.S.), and Czech Ministry of Health (RVO VFN64165 to L.V.)