Risk of chronic kidney disease in patients with non-alcoholic fatty liver disease: is there a link?

Multiparametric MRI assessment of renal blood oxygenation, fat content, and hemodynamics in an animal model of metabolic dysfunction-associated steatotic liver disease

Aims

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a significant risk factor for chronic kidney disease. There is a lack of an accurate and comprehensive technique for detecting MASLD-related renal injury. This study aims to evaluate the efficacy of arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) imaging, and proton density fat fraction (PDFF) for assessing renal injury in an animal model of MASLD.

Methods

An animal model of MASLD was established using a high-fat diet. Forty-nine 6-week-old male Sprague-Dawley rats were divided into the pathology (14, 16, 18, 20, 22, and 24 weeks, n = 7 per subgroup) and continuous-scanning (n = 7) groups. Renal alterations at different time points were quantified through the application of ASL-renal blood flow (RBF), BOLD-T2*, and Fat Fraction (FF), alongside pathological indices and blood biochemical markers.

Results

RBF did not change significantly from 14-24 weeks, consistent with the peritubular capillary density. Compared with those at week 14, renal T2* significantly decreased at week 20, FF increased at week 20, and serum creatine levels increased at week 24. Renal T2* and FF were significantly correlated with renal H&E scores and HIF-1α expression (|r| = 0.3552-0.7745). Kidney BOLD-T2*, liver and kidney FF enabled detecting renal injury in an animal model of MASLD (area under the curve = 0.76-0.86).

Conclusion

During fatty liver disease progression, renal blood oxygen levels decreased, fat deposition increased, and blood flow remained unchanged. BOLD and PDFF allowed accurately quantifying these changes to facilitate early detection of kidney injury.

Construction and validation of a nomogram for detecting chronic kidney disease in patients with nonalcoholic fatty liver disease: Insights from the NHANES database

BACKGROUND AND OBJECTIVES

Fatty liver disease is often associated with renal impairment in many patients. Early detection and prompt intervention are crucial for improving patient quality of life and reducing mortality rates. This study aimed to develop and validate a nomogram for detecting the risk of Chronic Kidney Disease (CKD) comorbidity in adults with Nonalcoholic Fatty Liver Disease (NAFLD) in the United States.

METHODS

From the NHANES (2017‒2020) database, the authors enrolled 2848 NAFLD participants, of whom 633 also had CKD. The authors employed the Least Absolute Shrinkage and Selection Operator (LASSO) regression and multivariate logistic regression to identify variables with predictive value. The overlapping features were selected to construct a predictive model, which was presented as a nomogram. The effectiveness of the nomogram was evaluated using Receiver Operating Characteristic (ROC) curves, calibration plots, and decision curve analysis.

RESULTS

Six indicators were included in the model: age, systolic blood pressure, serum albumin, high-sensitivity C-reactive protein, total cholesterol, and triglycerides. The area under the curve of the nomogram for predicting CKD in the training set was 0.772, with a 95 % Confidence Interval (95 % CI) of 0.746 to 0.797. In the validation set, the area under the curve was 0.722, with a 95 % CI of 0.680 to 0.763. The calibration curve analyses demonstrated that the prediction outcomes of the model aligned well with the actual outcomes, indicating good clinical applicability.

CONCLUSIONS

The nomogram demonstrated excellent performance and has the potential to serve as an auxiliary tool for detecting CKD in NAFLD patients.

From Liver to Kidney: The Overlooked Burden of Nonalcoholic Fatty Liver Disease in Chronic Kidney Disease

Nonalcoholic fatty liver disease (NAFLD) is increasingly recognized as a contributor to chronic kidney disease (CKD), yet its impact remains underappreciated in clinical practice. Recent studies reveal a strong association between NAFLD and CKD progression, with evidence linking hepatic dysfunction to renal impairment through metabolic and inflammatory pathways. NAFLD not only increases the risk of CKD but also accelerates its progression, leading to worse cardiovascular outcomes and higher mortality, particularly in patients with advanced fibrosis. Despite this growing evidence, NAFLD often goes undiagnosed in CKD patients and routine hepatic evaluation is rarely integrated into nephrology care. Emerging diagnostic tools, including noninvasive biomarkers and imaging techniques, offer potential for earlier detection, yet their clinical implementation remains inconsistent. Although lifestyle modifications remain the foundation of treatment, pharmacotherapeutic strategies, including SGLT2 inhibitors and GLP-1 receptor agonists, have demonstrated potential in mitigating both hepatic and renal impairment. Recognizing the interplay between NAFLD and CKD is essential for improving patient outcomes. A multidisciplinary approach, integrating hepatology and nephrology expertise, is crucial to refining screening strategies, optimizing treatment, and reducing the long-term burden of these coexisting conditions.

Identifying proteins and pathways associated with multimorbidity in 53,026 adults

BACKGROUND AND AIMS

Multimorbidity, the coexistence of multiple chronic diseases, is a rapidly expanding global health challenge, carrying profound implications for patients, caregivers, healthcare systems, and society. Investigating the determinants and drivers underlying multiple chronic diseases is a priority for disease management and prevention.

METHOD

This prospective cohort study analyzed data from the 53,026 participants in the UK Biobank from baseline (2006 to 2010) across 13.3 years of follow-up. Using Cox proportional hazards regression model, we characterized shared and unique associations across 38 incident outcomes (31 chronic diseases, 6 system mortality and all-cause mortality). Furthermore, ordinal regression models were used to assess the association between protein levels and multimorbidity (0-1, 2, 3-4, or ≥ 5 chronic diseases). Functional and tissue enrichment analysis were employed for multimorbidity-associated proteins. The upstream regulators of above proteins were identified.

RESULTS

We demonstrated 972 (33.3 %) proteins were shared across at least two incident chronic diseases after Bonferroni correction (P < 3.42 × 10-7, 93.3 % of those had consistent effects directions), while 345 (11.8 %) proteins were uniquely linked to a single chronic disease. Remarkably, GDF15, PLAUR, WFDC2 and AREG were positively associated with 20-24 incident chronic diseases (hazards ratios: 1.21-3.77) and showed strong associations with multimorbidity (odds ratios: 1.33-1.89). We further identified that protein levels are explained by common risk factors, especially renal function, liver function, inflammation, and obesity, providing potential intervention targets. Pathway analysis has underscored the pivotal role of the immune response, with the top three transcription factors associated with proteomics being NFKB1, JUN and RELA.

CONCLUSIONS

Our results enhance the understanding of the biological basis underlying multimorbidity, offering biomarkers for disease identification and novel targets for therapeutic intervention.

Association between Noninvasive Liver Biomarkers and Graft Outcomes in Kidney Transplantation Recipients

INTRODUCTION

Although studies have suggested that metabolic risk profiles are prognostic factors in kidney transplantation recipients (KTRs), the prognostic value of fatty liver, a known surrogate of metabolic risk, in KTRs remains to be elucidated. The objective of this study was to investigate the association between noninvasive liver biomarkers used to assess hepatic steatotic and fibrotic burdens and graft outcomes in KTRs.

METHODS

A total of 3,092 patients who underwent deceased or living donor kidney transplantation (KT) between January 2000 and December 2022 were enrolled. Postoperative hepatic fibrotic burdens of KTRs were assessed using the fibrosis-4 (FIB-4) score and the non-alcoholic fatty liver disease fibrosis score (NFS). The primary outcome was a composite of 50% estimated glomerular filtration rate (eGFR) decline and graft failure. Secondary outcomes included individual outcomes of 50% eGFR decline, graft failure, and acute rejection.

RESULTS

For the primary outcome, during a mean follow-up of 6.0 years, the composite outcome occurred in 519 (16.8%) participants. When stratified into three groups according to FIB-4 score categories, the highest score group (FIB-4 ≥2.67) had a 2.05-fold (95% confidence interval [CI], 1.44-2.91; p < 0.001) higher risk of the composite outcome compared to the lowest score group (FIB-4 <1.30). Furthermore, the highest score group showed higher risk of the secondary outcomes, with hazard ratios (95% CI) of 1.75 (1.16-2.66), 1.62 (1.06-2.46), and 2.23 (1.43-3.46) for 50% eGFR decline, acute rejection, and graft failure, respectively. Similar findings were observed for NFS.

CONCLUSIONS

Higher hepatic fibrotic burdens were associated with unfavorable graft outcomes in KTRs.

Association of Comorbidity Duration with the Occurrence and Prognosis of Steatotic Liver Disease

BACKGROUND AND AIMS

Steatotic liver disease (SLD) interacts with various comorbidities, impacting outcomes, yet little is known about the duration of comorbidities in SLD occurrence and mortality. We investigated this relationship, focusing on disease predictors and mortality rates.

APPROACH

Analyzing 2010 and 2015 Korea National Health and Nutrition Examination Survey data for patients aged ≥ 20, we categorized ten comorbidities (hypertension [HTN], diabetes mellitus [DM], dyslipidemia, stroke, myocardial infarction [MI], angina pectoris, asthma, chronic obstructive lung disease [COPD], chronic kidney disease [CKD], and depression) by duration. Association rule mining and logistic regression analyzed the association between SLD occurrence and comorbidity duration, while Cox regression assessed survival.

RESULTS

The analysis included 2,757 SLD and 9,505 non-SLD cases. Association rule mining showed that the shorter duration of DM and dyslipidemia and the longer duration of HTN comprised the top-ranked component for presence of SLD. DM with a duration ≤ 1 year showed higher risk of SLD than longer periods (odds ratio, 11.53), while the duration of cardiovascular disease, lung disease, or CKD was not significantly associated with the presence of SLD. In terms of prognosis, multivariate Cox regression showed that longer HTN and DM durations were significantly associated with increased hazard ratio (HR) beyond 10 years (HR, 2.22 and 2.11, respectively). Cardiovascular disease duration ≤ 5 years and lung disease duration > 5 years showed statistical significance (HR 2.49and 2.38, respectively).

CONCLUSIONS

Duration of comorbidities should be considered for comprehensive SLD risk stratification, for both the identification of SLD and the assessment of their prognosis after detection.

Exploring Biomarkers in Nonalcoholic Fatty Liver Disease Among Individuals With Type 2 Diabetes Mellitus

Integrating biomarkers into a comprehensive strategy is crucial for precise patient management, especially considering the significant healthcare costs associated with diseases. Current studies emphasize the urgent need for a paradigm shift in conceptualizing nonalcoholic fatty liver disease (NAFLD), now renamed metabolic dysfunction-associated steatotic liver disease (MASLD). Biomarkers are emerging as indispensable tools for accurate diagnosis, risk stratification, and monitoring disease progression. This review classifies biomarkers into conventional and novel categories, such as lipids, insulin resistance, hepatic function, and cutting-edge imaging/omics, and evaluates their potential to transform the approach to MASLD among individuals with type 2 diabetes mellitus (T2D). It focuses on the critical role of biomarkers in early MASLD detection, enhancing predictive accuracy, and discerning responses to interventions (pharmacological or lifestyle modifications). Amid this discussion, the complexities of the relationship between T2D and MASLD are explored, considering factors like age, gender, genetics, ethnicity, and socioeconomic background. Biomarkers enhance the effectiveness of interventions and support global initiatives to reduce the burden of MASLD, thereby improving public health outcomes. This review recognizes the promising potential of biomarkers for diagnostic precision while candidly addressing the challenges in implementing these advancements in clinical practice. The transformative role of biomarkers emerges as a central theme, promising to reshape our understanding of disease trajectories, prognosis, and the customization of personalized therapeutic strategies for improved patient outcomes. From a future perspective, identifying early-stage biomarkers, understanding environmental impact through exposomes, and applying a multiomics approach may reveal additional insight into MASLD development.

Hepatokines and MASLD: The GLP1-Ras-FGF21-Fetuin-A Crosstalk as a Therapeutic Target

The introduction of the term "Metabolic Steatotic Liver Disease" (MASLD) underscores the critical role of metabolic dysfunction in the development and progression of chronic liver disease and emphasizes the need for strategies that address both liver disease and its metabolic comorbidities. In recent years, a liver-focused perspective has revealed that altered endocrine function of the fatty liver is a key contributor to the metabolic dysregulation observed in MASLD. Due to its secretory capacity, the liver's increased production of proteins known as "hepatokines" has been linked to the development of insulin resistance, explaining why MASLD often precedes dysfunction in other organs and ultimately contributes to systemic metabolic disease. Among these hepatokines, fibroblast growth factor 21 (FGF21) and fetuin-A play central roles in regulating the metabolic abnormalities associated with MASLD, explaining why their dysregulated secretion in response to metabolic stress has been implicated in the metabolic abnormalities of MASLD. This review postulates why their modulation by GLP1-Ras may mediate the beneficial metabolic effects of these drugs, which have increased attention to their emerging role as pharmacotherapy for MASLD. By discussing the crosstalk between GLP1-Ras-FGF21-fetuin-A, this review hypothesizes that the possible modulation of fetuin-A by the novel GLP1-FGF21 dual agonist pharmacotherapy may contribute to the management of metabolic and liver diseases. Although research is needed to go into the details of this crosstalk, this topic may help researchers explore the mechanisms by which this type of pharmacotherapy may manage the metabolic dysfunction of MASLD.

The Fatty Liver Index's Association with Incident Chronic Kidney Disease in Korean Middle-Aged Adults: A Community-Based Cohort Study

(1) Background: The relationship between nonalcoholic fatty liver disease (NAFLD) and incident chronic kidney disease (CKD) is unclear, and long-term follow-up data are limited. Therefore, this study aimed to evaluate whether NAFLD, as assessed by the fatty liver index (FLI), could predict the development of CKD in a community-based Korean cohort over 16 years. (2) Methods: Among the 10,030 total participants, 7778 patients without CKD were selected from the Korean Genome and Epidemiology Study (KoGES). The FLI grade ranged from 0 to 100 and was divided into three groups: low (FLI, <30), intermediate (FLI, 30-59), and high (FLI, ≥60). An estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2 or the development of proteinuria was considered to indicate incident CKD. (3) Results: During the 16-year follow-up period, 919 individuals (11.8%) developed CKD. The HRs of incident CKD in the intermediate FLI group (30-59) and high FLI group (≥60) increased compared with the reference low FLI group (<30) after adjusting for potentially confounding variables. NAFLD, as assessed by the FLI, was an independent risk factor for CKD. (4) Conclusions: Our findings suggest that the FLI, a simple surrogate biomarker of fatty liver disease, may be used to identify people at high risk of incident CKD in clinical practice.

The Fatty Liver Index, the Strongest Risk Factor for Low Testosterone Level

INTRODUCTION

The study aimed to determine if hepatic steatosis assessed by fatty liver index (FLI) was an independent risk factor for male low testosterone level and whether the FLI was the strongest risk factor for low testosterone level in two different age groups.

METHODS

Two cross-sectional studies were performed. A total of 3,443 male participants (aged 46-75) were recruited into study A (part of lONgitudinal study (REACTION)). Then a total of 267 male participants (aged 25-45) were recruited into study B. Serum total testosterone (TT) and sex hormone-binding globulin (SHBG) levels, indicators for assessing hepatic steatosis were measured. The Pearson correlation and regression analysis were performed to investigate the risk factors for low testosterone level.

RESULTS

The FLI had the strongest negative correlation with serum testosterone in the study A (r = -0.436) and B (r = -0.542). Compared with patients with a FLI lower than 30, the risk for low testosterone level increased by 3.48-fold in subjects with a FLI higher than 60 adjusted for potential risk factors in study A. In study B, the odds ratio of low testosterone level in patients with potential hepatic steatosis was 4.26 (1.57-11.60) after adjusted for age and homeostasis model assessment of insulin resistance (HOMA-IR) and 0.59 (0.14-2.60) after adjusted for age, HOMA-IR, waist circumference, body mass index, and SHBG.

CONCLUSIONS

FLI was the strongest risk factor for male low testosterone level independent of insulin resistance in male populations of different ages; however, the association can be modulated by SHBG levels in the young.

SIGNIFICANCE STATEMENT

In the study, FLI was the strongest negative risk factor for low testosterone level in the Chinese adult male population. The results suggested that hepatic steatosis assessed by the FLI was the main risk factor for male low testosterone level, independent of age, insulin resistance, smoking, and drinking status; however, the association of FLI and TT levels can be modulated by SHBG levels. Taken together these findings indicate that clinical physicians should pay more attention to the FLI index and hepatic steatosis, so that they can take advantage of them for assessing the risk of developing of low testosterone level in the male population.

Renal damage in Hepatorenal Syndrome: A still unsolved issue

Acute kidney injury (AKI) is a common complication of cirrhosis, burdened by high morbidity and mortality rates and progression to chronic kidney disease. Hepatorenal syndrome (HRS) is a peculiar type of functional AKI observed in cirrhotic patients with ascites. HRS diagnosis is still clinical, once pre-renal azotemia and intrinsic kidney damage have been excluded by applying well-established and internationally adopted criteria. HRS is considered reversible because of the absence of intrinsic renal damage. However, HRS reversibility has been questioned, due to the lack of response to treatment with vasoconstrictors plus albumin in a relevant percentage of patients and to the persistence of renal dysfunction in HRS patients who underwent liver transplantation (LT). Indeed, LT is the only ultimate treatment, as it solves both liver failure and portal hypertension. Thus, the presence of renal damage in HRS can be hypothesized. In this scenario, neutrophil gelatinase-associated lipocalin (NGAL), one of the most promising biomarkers, may help in characterizing the type of renal injury, distinguishing between HRS and acute tubular necrosis. This review gathers the available evidence in favor and against the presence of structural lesions in HRS in terms of either renal histology and urinary biomarkers with a particular focus on NGAL. The ability to properly characterize which component of renal dysfunction prevails - functional rather than structural - entails a relevant clinical impact for the treatment of these patients, both in terms of medical therapy and liver vs. combined liver-kidney transplantation.

Metabolic disorders induced by PNPLA3 and TM6SF2 gene variants affect chronic kidney disease in patients infected with non-genotype 3 hepatitis C virus

BACKGROUND

Patients with chronic hepatitis C virus (HCV) infections differ in their risk for metabolic disorders and chronic kidney disease (CKD). The aim of this study was to investigate the effect of metabolic disorders induced by genetic factors on CKD in HCV-infected patients.

METHODS

Patients with chronic non-genotype 3 HCV infection with or without CKD were examined. PNPLA3 and TM6SF2 variants were determined using high-throughput sequencing. The relationships of variants and different combinations with metabolic disorders were analyzed in CKD patients. Univariate and multivariate analyses were used to identify factors associated with CKD.

RESULTS

There were 1022 patients with chronic HCV infection, 226 with CKD and 796 without CKD. The CKD group had more severe metabolic disorders, and also had higher prevalences of liver steatosis, the PNPLA3 rs738409 non-CC genotype, and the TM6SF2 rs58542926 CC genotype (all P < 0.05). Relative to patients with the PNPLA3 rs738409 CC genotype, patients with the non-CC genotype had a significantly decreased eGFR and a greater prevalence of advanced CKD (CKD G4-5). Patients with the TM6SF2 rs58542926 CC genotype had a lower eGFR and a higher prevalence of CKD G4-5 than those with the non-CC genotype. Multivariable analysis indicated that multiple metabolic abnormalities, including liver steatosis and the PNPLA3 rs738409 C > G variant, increased the risk of CKD, but the TM6SF2 rs58542926 C > T variant decreased the risk of CKD.

CONCLUSION

Specific PNPLA3 rs738409 and TM6SF2 rs58542926 variants are independent risk factors for CKD in patients with chronic HCV infections and are associated with the severity of renal injury.

Impact of metabolic risk factors on hepatic and cardiac outcomes in patients with alcohol- and non-alcohol-related fatty liver disease

Background & Aims

Metabolic risk factors (MetRs) are associated with hepatic and cardiac outcomes in patients with fatty liver disease (FLD). We evaluated whether MetRs have different effects on alcoholic FLD (AFLD) and non-alcoholic FLD (NAFLD).

Methods

We used a standardised common data model to analyse data from seven university hospital databases between 2006 and 2015. MetRs included diabetes mellitus, hypertension, dyslipidaemia, and obesity. Follow-up data were analysed for the incidence of hepatic outcomes, cardiac outcomes, and death in patients with AFLD or NAFLD and based on MetRs within AFLD and NAFLD.

Results

Out of 3,069 and 17,067 patients with AFLD and NAFLD, respectively, 2,323 (75.7%) and 13,121 (76.9%) had one or more MetR, respectively. Patients with AFLD were at a higher risk of hepatic outcomes (adjusted risk ratio [aRR], 5.81) compared with those with NAFLD irrespective of MetR. The risk of cardiac outcomes in AFLD and NAFLD became similar with the increasing number of MetRs. Patients with NAFLD without MetRs demonstrated a lower risk of cardiac outcomes, but not hepatic outcomes, compared with those with MetRs (aRR, 0.66 and 0.61 for MetR ≥1 and MetR ≥2, respectively; p <0.05). In patients with AFLD, hepatic and cardiac outcomes were not associated with MetRs.

Conclusions

The clinical impact of MetRs in patients with FLD may differ between patients with AFLD and those with NAFLD.

Impact and Implications

With the increasing prevalence of fatty liver disease (FLD) and metabolic syndrome, the increase in associated complications, such as liver and heart diseases, has become an important social issue. Particularly in patients with FLD with excessive alcohol consumption, the incidence of liver and heart disease is pronounced because of the dominant effect of alcohol over the effects of other factors. Thus, appropriate screening and management of alcohol consumption in patients with FLD are vital.

Genetic deletion of phosphodiesterase 4D in the liver improves kidney damage in high-fat fed mice: liver-kidney crosstalk

A growing body of epidemiological evidence suggests that nonalcoholic fatty liver disease (NAFLD) is an independent risk factor for chronic kidney disease (CKD), but the regulatory mechanism linking NAFLD and CKD remains unclear. Our previous studies have shown that overexpression of PDE4D in mouse liver is sufficient for NAFLD, but little is known about its role in kidney injury. Here, liver-specific PDE4D conditional knockout (LKO) mice, adeno-associated virus 8 (AAV8)-mediated gene transfer of PDE4D and the PDE4 inhibitor roflumilast were used to assess the involvement of hepatic PDE4D in NAFLD-associated renal injury. We found that mice fed a high-fat diet (HFD) for 16 weeks developed hepatic steatosis and kidney injury, with an associated increase in hepatic PDE4D but no changes in renal PDE4D. Furthermore, liver-specific knockout of PDE4D or pharmacological inhibition of PDE4 with roflumilast ameliorated hepatic steatosis and kidney injury in HFD-fed diabetic mice. Correspondingly, overexpression of hepatic PDE4D resulted in significant renal damage. Mechanistically, highly expressed PDE4D in fatty liver promoted the production and secretion of TGF-β1 into blood, which triggered kidney injury by activating SMADs and subsequent collagen deposition. Our findings revealed PDE4D might act as a critical mediator between NAFLD and associated kidney injury and indicated PDE4 inhibitor roflumilast as a potential therapeutic strategy for NAFLD-associated CKD.

Metabolic dysfunction-associated fatty liver disease predicts new onset of chronic kidney disease better than fatty liver or nonalcoholic fatty liver disease

BACKGROUND

Possible associations of chronic kidney disease (CKD) with fatty liver (FL) and nonalcoholic fatty liver disease (NAFLD) have recently been focused on. Metabolic dysfunction-associated fatty liver disease (MAFLD), defined as FL with overweight/obesity, type 2 diabetes mellitus or metabolic abnormalities, has been proposed as a new feature of chronic liver disease. However, the relationship between MAFLD and new onset of CKD has not been fully addressed.

METHODS

We investigated the associations of FL, NAFLD and MAFLD with the development of CKD, defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 or positive for urinary protein, over a 10-year period in 28 890 Japanese subjects who received annual health examinations. After exclusion of subjects with no data for abdominal ultrasonography and subjects with CKD at baseline, a total of 13 159 subjects (men 8581, women 4578; mean age 48 years) were recruited.

RESULTS

The prevalence of FL, NAFLD and MAFLD was 34.6% (men 45.1%, women 15.1%), 32.8% (men 42.7%, women 14.5%) and 32.3% (men 42.4%, women 13.4%), respectively. During the 10-year follow-up period, 2163 subjects (men 1475, women 688) had new onset of CKD. Multivariable Cox proportional hazards model analyses showed that MAFLD [hazard ratio 1.12 (95% confidence interval 1.02-1.26); P = .027] but not FL or NAFLD was an independent risk factor for new onset of CKD after adjustment of age, sex, eGFR, current smoking habit, ischemic heart disease, diabetes mellitus, overweight/obesity, hypertension and dyslipidemia. The addition of MAFLD [continuous net reclassification improvement (NRI) 0.154, integrated discrimination improvement (IDI) 0.0024] to traditional risk factors without metabolic abnormalities significantly improved the discriminatory capacity better than did the addition of FL (NRI 0.138, IDI 0.0018) or NAFLD (NRI 0.132, IDI 0.0017).

CONCLUSIONS

MAFLD is modestly and independently associated with new onset of CKD and predicts the risk for development of CKD better than FL or NAFLD.

Can Zinc Supplementation Attenuate High Fat Diet-Induced Non-Alcoholic Fatty Liver Disease?

The pathogenesis of non-alcoholic fatty liver disease (NAFLD), the most prevalent chronic liver disease, is associated with zinc deficiency. Previous studies show zinc supplementation improves steatosis and glucose metabolism, but its therapeutic effects in patients with established NAFLD remain unclear. We developed an in vivo model to characterize the effects of zinc supplementation on high-fat diet (HFD) induced NAFLD and hypothesized that the established NAFLD would be attenuated by zinc supplementation. Male C57BL/6J mice were fed a control diet or HFD for 12 weeks. Mice were then further grouped into normal and zinc-supplemented diets for 8 additional weeks. Body composition and glucose tolerance were determined before and after zinc supplementation. At euthanasia, plasma and liver tissue were collected for characterization and downstream analysis. As expected, 12 weeks of HFD resulted in reduced glucose clearance and altered body composition. Eight weeks of subsequent zinc supplementation did not alter glucose handling, plasma transaminases, steatosis, or hepatic gene expression. Results from our model suggest 8-week zinc supplementation cannot reverse established NAFLD. The HFD may have caused NAFLD disease progression beyond rescue by an 8-week period of zinc supplementation. Future studies will address these limitations and provide insights into zinc as a therapeutic agent for established NAFLD.

Liver steatosis and fibrosis markers' association with cardiovascular and renal damage in Japanese adults: the TMM BirThree cohort study

INTRODUCTION AND OBJECTIVES

Patients with non-alcoholic fatty liver disease (NAFLD) are at risk for cardiovascular and chronic kidney diseases. Liver steatosis and fibrosis were assessed using the fatty liver index and fibrosis-4 index, respectively. This study aimed to examine the association between these two parameters in patients with atherosclerosis and chronic kidney disease.

MATERIALS AND METHODS

The two parameters were calculated for 11,867 adults who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. Intima-media thickness and estimated glomerular filtration rate were also measured. Logistic regression models were used to estimate the odds ratios (OR).

RESULTS

Overall, 4257 (35.9%) and 4733 (39.9%) participants had a higher probability of liver steatosis and fibrosis, respectively. The adjusted OR of higher fatty liver index compared to lower fatty liver index for atherosclerosis and chronic kidney disease were 0.98 (95% confidence interval [CI], 0.77-1.24) and 1.79 (95% CI, 1.19-2.69), and those of higher FIB-4 compared to lower FIB-4 were 1.03 (95% CI, 0.82-1.30) and 0.79 (95% CI, 0.52-1.19) for atherosclerosis and chronic kidney disease, respectively.

CONCLUSIONS

A higher FLI was associated with CKD independent of other risk factors. Further research is required to identify the causal relationship between liver fat accumulation and CKD.

Cardiovascular and renal burdens among patients with MAFLD and NAFLD in China

BACKGROUND/PURPOSE

Metabolic associated fatty liver disease (MAFLD) was proposed as a new definition to put emphasis on the metabolic aspects of nonalcoholic fatty liver disease (NAFLD). We aim to compare the cardiovascular and renal burden between MAFLD and NAFLD patients.

METHODS

12183 participants were enrolled in East China. The cardiovascular burden (Framingham risk score and previous cardiovascular diseases (CVD)) and renal burden (eGFR and chronic kidney disease (CKD)) were measured.

RESULTS

The risk of hypertension, dyslipidemia, diabetes, overweight/obesity, and central obesity of MAFLD patients were higher than those of NAFLD. Patients with MAFLD have a similar or higher beta coefficients in Framingham risk score [beta (95%CI): male 0.062 (0.055,0.069) vs 0.041 (0.033,0.048); female 0.014 (0.012,0.016) vs 0.012 (0.01,0.014)], and higher odds ratio in previous CVD [odds ratio (95%CI): male 1.50 (1.22,1.85) vs 1.35 (1.1,1.66); female 1.58 (1.33,1.87) vs 1.45 (1.22,1.72)], compared with those with NAFLD. However, compared with males with MAFLD, the odds ratio of CKD was higher in those with NAFLD [eGFR: -2.731 (-3.422, -2.041) vs-3.578 (-4.268, -2.887). CKD: 1.44 (1.05,1.96) vs 1.56 (1.14,2.12)]. In female, CKD was only marginally associated with NAFLD [0.8 (0.62,1.02), P=0.075], but not MAFLD [0.87 (0.68,1.11), P=0.268].

CONCLUSIONS

Patients with MAFLD have a similar or higher risk of future and previous CVD compared with those with NAFLD, but the risk of CKD was higher in male with NAFLD.

Crosstalk between kidney and liver in non-alcoholic fatty liver disease: mechanisms and therapeutic approaches

Liver and kidney are vital organs that maintain homeostasis and injury to either of them triggers pathogenic pathways affecting the other. For example, non-alcoholic fatty liver disease (NAFLD) promotes the progression of chronic kidney disease (CKD), vice versa acute kidney injury (AKI) endorses the induction and progression of liver dysfunction. Progress in clinical and basic research suggest a role of excessive fructose intake, insulin resistance, inflammatory cytokines production, activation of the renin-angiotensin system, redox imbalance, and their impact on epigenetic regulation of gene expression in this context. Recent developments in experimental and clinical research have identified several biochemical and molecular pathways for AKI-liver interaction, including altered liver enzymes profile, metabolic acidosis, oxidative stress, activation of inflammatory and regulated cell death pathways. This review focuses on the current preclinical and clinical findings on kidney-liver crosstalk in NAFLD-CKD and AKI-liver dysfunction settings and highlights potential molecular mechanisms and therapeutic targets.

Development and implementation of patient-level prediction models of end-stage renal disease for type 2 diabetes patients using fast healthcare interoperability resources

This study aimed to develop a model to predict the 5-year risk of developing end-stage renal disease (ESRD) in patients with type 2 diabetes mellitus (T2DM) using machine learning (ML). It also aimed to implement the developed algorithms into electronic medical records (EMR) system using Health Level Seven (HL7) Fast Healthcare Interoperability Resources (FHIR). The final dataset used for modeling included 19,159 patients. The medical data were engineered to generate various types of features that were input into the various ML classifiers. The classifier with the best performance was XGBoost, with an area under the receiver operator characteristics curve (AUROC) of 0.95 and area under the precision recall curve (AUPRC) of 0.79 using three-fold cross-validation, compared to other models such as logistic regression, random forest, and support vector machine (AUROC range, 0.929–0.943; AUPRC 0.765–0.792). Serum creatinine, serum albumin, the urine albumin-to-creatinine ratio, Charlson comorbidity index, estimated GFR, and medication days of insulin were features that were ranked high for the ESRD risk prediction. The algorithm was implemented in the EMR system using HL7 FHIR through an ML-dedicated server that preprocessed unstructured data and trained updated data.

Proteomics and Phosphoproteomics of Circulating Extracellular Vesicles Provide New Insights into Diabetes Pathobiology

The purpose of this study was to define the proteomic and phosphoproteomic landscape of circulating extracellular vesicles (EVs) in people with normal glucose tolerance (NGT), prediabetes (PDM), and diabetes (T2DM). Archived serum samples from 30 human subjects (n = 10 per group, ORIGINS study, NCT02226640) were used. EVs were isolated using EVtrap®. Mass spectrometry-based methods were used to detect the global EV proteome and phosphoproteome. Differentially expressed features, correlation, enriched pathways, and enriched tissue-specific protein sets were identified using custom R scripts. Phosphosite-centric analyses were conducted using directPA and PhosR software packages. A total of 2372 unique EV proteins and 716 unique EV phosphoproteins were identified among all samples. Unsupervised clustering of the differentially expressed (fold change ≥ 2, p < 0.05, FDR < 0.05) proteins and, particularly, phosphoproteins showed excellent discrimination among the three groups. CDK1 and PKCδ appear to drive key upstream phosphorylation events that define the phosphoproteomic signatures of PDM and T2DM. Circulating EVs from people with diabetes carry increased levels of specific phosphorylated kinases (i.e., AKT1, GSK3B, LYN, MAP2K2, MYLK, and PRKCD) and could potentially distribute activated kinases systemically. Among characteristic changes in the PDM and T2DM EVs, “integrin switching” appeared to be a central feature. Proteins involved in oxidative phosphorylation (OXPHOS), known to be reduced in various tissues in diabetes, were significantly increased in EVs from PDM and T2DM, which suggests that an abnormally elevated EV-mediated secretion of OXPHOS components may underlie the development of diabetes. A highly enriched signature of liver-specific markers among the downregulated EV proteins and phosphoproteins in both PDM and T2DM groups was also detected. This suggests that an alteration in liver EV composition and/or secretion may occur early in prediabetes. This study identified EV proteomic and phosphoproteomic signatures in people with prediabetes and T2DM and provides novel insight into the pathobiology of diabetes.

Metabolic Associated Fatty Liver Disease (MAFLD) Increases the Risk of Systemic Complications and Mortality. A Meta-Analysis and Systematic Review of 12,620,736 Individuals

INTRODUCTION

The recent introduction of the definition "metabolic associated fatty liver disease" (MAFLD) sought to reclassify non-alcoholic fatty liver disease (NAFLD). MAFLD is thought to improve the encapsulation of metabolic dysregulation. However, recent evidence has found significant differences between MAFLD and NAFLD and prevailing knowledge has largely arisen from studies in NAFLD. Hence, we conducted a meta-analysis and systematic review on the outcomes associated with MAFLD.

METHODS

Medline and Embase database were searched for articles relating to outcomes in MAFLD. Analysis was conducted in random effects with hazard ratios to account for longitudinal risk assessment of mortality and systemic complications.

RESULTS

A total of 554 articles were identified and a final total of 17 articles were included. MAFLD resulted in an increase of overall mortality (HR 1.24, CI: 1.13 - 1.34), cancer related mortality (HR: 1.27, CI: 1.01 - 1.54) and CVD mortality (HR: 1.28, 1.03 - 1.53, p=0.04) compared to non MAFLD. MAFLD also increases the risk of cardiovascular events (HR: 1.49, CI: 1.34 - 1.64, p<0.01), stroke (HR: 1.55, CI: 1.37 - 1.73, p<0.01) and chronic kidney disease (HR: 1.53, CI: 1.38 - 1.68). The presence of MAFLD was also associated with an increased risk of heart failure, obstructive sleep apnoea and malignancy.

CONCLUSIONS

MAFLD can significantly elevate the risk of systemic diseases and mortality. The care of MAFLD thus requires interdisciplinary collaboration and future clinical trials conducted in MAFLD should aim to reducing the incidence of end organ damage aside from improving liver histology.

Influence of Nonalcoholic Fatty Liver Disease on the Occurrence and Severity of Chronic Kidney Disease

Nonalcoholic fatty liver disease (NAFLD) is reported to affect 20-30% of adults and is accompanied by various metabolic comorbidities, where the economic and clinical burden of NAFLD is attributed to the progression of liver disease as well as the presence of extrahepatic diseases. Chronic kidney disease (CKD), which has a high incidence rate, high morbidity and mortality rates, and high medical costs, has been linked to NAFLD. CKD is associated with some metabolism-related risk factors that overlap with metabolic comorbidities of NAFLD. Therefore, to investigate the potential factors that influence CKD occurrence, the association between NAFLD and CKD should be clarified. Some studies have confirmed that NAFLD influences the occurrence and severity of CKD, whereas some studies have indicated that there is no correlation. In this review, the results of a few studies have been discussed, the potential risk factors for CKD in NAFLD are explored, and the respective biological mechanisms are elaborated to help clinicians identify CKD in patients much earlier than it is diagnosed now and thus help in reducing the incidence of liver and kidney transplants.

Association Between the Risk of Non-Alcoholic Fatty Liver Disease in Patients with Type 2 Diabetes and Chronic Kidney Disease

OBJECTIVE

To explore the relationship between non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 1168 patients with T2DM were divided into the non-CKD and CKD groups, and the difference in the prevalence of NAFLD was compared. The differences in serum creatinine (SCr) and urine albumin-to-creatinine ratio (UACR) levels were compared between the non-NAFLD and NAFLD groups. Patients with T2DM were divided into three groups according to their UACR levels (UACR < 30 mg/g [U1 group]; UACR ≤ 30 mg/g to < 300 mg/g [U2 group]; and UACR ≥ 300 mg/g [U3 group]) or estimated glomerular filtration rate (eGFR) levels (≥ 90 mL/min [G1 group]; eGFR ≤ 60 mL/min to < 90 mL/min [G2 group]; and eGFR < 60 mL/min (G3 group]). The difference in the prevalence and risks of NAFLD in the different UACR or eGFR level groups was analyzed.

RESULTS

The prevalence of NAFLD in the CKD group was higher than that in the non-CKD group (63.5% vs 50.5%, p < 0.001). The SCr and UACR levels in the NAFLD group were higher than those in the non-NAFLD group (both p<0.05). The prevalence of NAFLD in the U3 group (75.6%) was higher than that in the U1 (50.5%, p < 0.05) and U2 (60.1%, p < 0.05) groups, and the prevalence of NAFLD in the U2 group (60.1%) was higher than that in the U1 group (50.5%, p < 0.05). The risk of NAFLD in the U3 group was higher than that in the U2 group (odds ratio [OR] = 3.032 and 1.473). Despite adjusting the parameters further, the NAFLD risk in the U3 group remained higher than that in the U2 group (OR = 1.660 and 2.342).

CONCLUSION

The risk of NAFLD in patients with T2DM is closely related to CKD.

Renal Tubular Damage Marker, Urinary N-acetyl-β-D-Glucosaminidase, as a Predictive Marker of Hepatic Fibrosis in Type 2 Diabetes Mellitus

BACKGROUND

Non-alcoholic steatohepatitis is closely associated with the progression of diabetic kidney disease (DKD) in type 2 diabetes mellitus (T2DM). We investigated whether urinary N-acetyl-β-D-glucosaminidase (u-NAG), an early renal tubular damage biomarker in DKD, could be related to the degree of hepatic fibrosis in patients with T2DM.

METHODS

A total of 300 patients with T2DM were enrolled in this study. Hepatic steatosis and fibrosis were determined using transient elastography. The levels of urinary biomarkers, including u-NAG, albumin, protein, and creatinine, and glucometabolic parameters were measured.

RESULTS

Based on the median value of the u-NAG to creatinine ratio (u-NCR), subjects were divided into low and high u-NCR groups. The high u-NCR group showed a significantly longer duration of diabetes, worsened hyperglycemia, and a more enhanced hepatic fibrosis index. A higher u-NCR was associated with a greater odds ratio for the risk of higher hepatic fibrosis stage (F2: odds ratio, 1.99; 95% confidence interval [CI], 1.04 to 3.82). Also, u-NCR was an independent predictive marker for more advanced hepatic fibrosis, even after adjusting for several confounding factors (β=1.58, P<0.01).

CONCLUSION

The elevation of u-NAG was independently associated with a higher degree of hepatic fibrosis in patients with T2DM. Considering the common metabolic milieu of renal and hepatic fibrosis in T2DM, the potential use of u-NAG as an effective urinary biomarker reflecting hepatic fibrosis in T2DM needs to be validated in the future.

How will NAFLD change the liver transplant landscape in the 2020s?

Liver steatosis is the hepatic manifestation of the metabolic syndrome, and is now the leading cause of chronic liver disease worldwide. The treatment of metabolic cirrhosis with liver failure and/or hepatocellular carcinoma is liver transplantation (LT). During the past decade, metabolic cirrhosis represented an increasing cause for LT, especially in the United States. At listing, patients with metabolic cirrhosis are older, with numerous cardiovascular (CV) and renal comorbidities, and this requires multidisciplinary pre-transplant assessment. After LT, 5-year survival is similar to other indications. The leading causes of death are infectious, cancers and CV. The recurrence of the initial disease is very frequent, and a significant part of the patients progress towards graft cirrhosis. No specific immunosuppressive regimen is recommended, but the toxicity profiles must probably be taken into account. In these patients, the only etiological treatment is that of obesity, in the absence of specific therapy for non-alcoholic steatohepatitis. The place of bariatric surgery has to be defined, probably sleeve gastrectomy, in a stable patient, 6-12 months after LT.

Non-Alcoholic Fatty Liver Disease Is Associated With Reduced Glomerular Filtration Rate in Patients With Chronic Plaque Psoriasis

BACKGROUND

Chronic plaque psoriasis has been associated with metabolic comorbidities, including non-alcoholic fatty liver disease (NAFLD). A causal relationship between NAFLD and chronic kidney disease (CKD) is debated.

OBJECTIVES

To assess whether NAFLD is associated with impaired renal function in patients with psoriasis.

METHODS

A multicenter, retrospective, observational study including 337 patients with moderate-to-severe chronic plaque psoriasis, who had no history of excessive alcohol consumption or other secondary causes of chronic liver and renal diseases was conducted. NAFLD was diagnosed by ultrasonography, and CKD stage ≥2 or stage ≥3 were defined by an estimated glomerular filtration rate (e-GFR) of <90 ml min^-1 1.73 m^-2 or <60 ml min^-1 1.73 m^-2, respectively. Logistic and linear regression analyses were undertaken to assess the independent association of NAFLD with CKD or eGFR levels.

RESULTS

Patients with NAFLD (n = 212, 62.9% of total) had significantly lower e-GFR levels (83.4 ± 18.0 vs. 93.5 ± 15.8 ml min^-1 1.73 m^-2, P<.001) and a remarkably higher prevalence of both CKD stage ≥2 (56.1% vs. 30.4%, P<.0001) and CKD stage ≥3 (10.4% vs. 3.2%, P<.0001) compared with their counterparts without NAFLD. Multivariable logistic regression analysis showed that NAFLD was associated with a nearly 2.5-fold increased risk of prevalent CKD stage ≥2 (adjusted-odds ratio= 2.60 95% confidence intervals 1.4-4.8, P=.02), independently of components of metabolic syndrome, psoriasis severity, and psoriatic arthritis.

CONCLUSIONS

Ultrasound-diagnosed NAFLD is strongly associated with a reduced eGFR in patients with moderate-to-severe psoriasis, independently of cardiometabolic risk factors and psoriasis-related variables.

Total C-21 Steroidal Glycosides From Baishouwu Ameliorate Hepatic and Renal Fibrosis by Regulating IL-1β/MyD88 Inflammation Signaling

Fibrosis is a worldwide public health problem, which typically results from chronic diseases and often leads to organ malfunction. Chronic inflammation has been suggested to be the major trigger for fibrogenesis, yet mechanisms by which inflammatory signals drive fibrogenesis have not been fully elucidated. Total C-21 steroidal glycosides (TCSG) from Baishouwu are the main active components of the root of Cynanchum auriculatum Royle ex Wight, which exert hepatoprotective and anti-inflammation properties. In this study, we established a mouse model with the coexistence of hepatic and renal fibrosis and aimed to investigate the effects of TCSG from Baishouwu on fibrosis and explored the potential mechanisms. The results of biochemical and pathological examinations showed that TCSG from Baishouwu improved liver and kidney function and alleviated hepatic and renal fibrosis by reducing collagen and extracellular matrix deposition in bile duct ligation and unilateral ureteral occlusion (BDL&UUO) mice. According to network pharmacology analysis, the mechanisms underlying the effects of TCSG from Baishouwu on hepatic and renal fibrosis were associated with inflammatory response pathways, including “Signaling by interleukins”, “MAP kinase activation”, “MyD88 cascade initiated on plasma membrane”, and “Interleukin-1 family signaling”. Regression analysis and western blot results revealed that IL-1β/MyD88 inflammation signaling played an essential role in the anti-fibrotic effects of TCSG from Baishouwu. Further data displayed that TCSG from Baishouwu affected inflammatory response and extracellular matrix deposition via suppressing the activation of p38 MAPK/JNK and NF-κB p65 signaling cascades both in the liver and kidney of BDL&UUO mice. Thus, our findings suggest TCSG from Baishouwu as a natural regimen against hepatic and renal fibrosis and provide direct evidence that IL-1β/MyD88 signaling crucially contributes to hepatic and renal fibrosis and modulates liver-kidney crosstalk by maintaining tight control over inflammatory responses.

Real-world Comorbidity Burden, Health Care Utilization, and Costs of Nonalcoholic Steatohepatitis Patients With Advanced Liver Diseases

GOALS

This study evaluates the real-world comorbidity burden, health care resource utilization (HRU), and costs among nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) patients with advanced liver diseases [compensated cirrhosis (CC), decompensated cirrhosis (DCC), liver transplantation (LT), hepatocellular carcinoma (HCC)].

BACKGROUND

NAFLD/NASH is a leading cause of liver diseases.

MATERIALS AND METHODS

Adult NAFLD/NASH patients were identified retrospectively from MarketScan Commercial claims (2006-2016). Following initial NAFLD/NASH diagnosis, advanced liver diseases were identified using the first diagnosis as their index date. Mean annual all-cause HRU and costs (2016 USD) were reported. Adjusted costs were estimated through generalized linear models. Cumulative costs were illustrated for patient subsets with variable follow-up for each stage.

RESULTS

Within the database, 485,774 NAFLD/NASH patients met eligibility criteria. Of these, 93.4% (453,564) were NAFLD/NASH patients without advanced liver diseases, 1.6% (7665) with CC, 3.3% (15,833) with DCC, 0.1% (696) with LT, and 0.1% (428) with HCC. Comorbidity burden was high and increased as patients progressed through liver disease severity stages. Compared with NAFLD/NASH without advanced liver diseases (adjusted costs: $23,860), the annual cost of CC, DCC, LT, and HCC were 1.22, 5.64, 8.27, and 4.09 times higher [adjusted costs: $29,078, $134,448, $197,392, and $97,563 (P<0.0001)]. Inpatient admissions significantly drove increasing HRU.

CONCLUSION

Study findings suggest the need for early identification and effective management of NAFLD/NASH patients to minimize comorbidity burden, HRU, and costs in the privately insured US population.

Hepatic fibrosis of any origin in a large population of type 2 diabetes patients

BACKGROUND AND AIMS

Excess morbidity and mortality from chronic liver disease in type 2 diabetes (T2DM) is recognized; however, the clinical features associated with liver fibrosis (LF) of any origin are poorly known. Metabolic status and/or coexisting complications over time may play a role.

METHODS AND RESULTS

We interrogated the database of the diabetes unit network of Piedmont (Italy) (71,285 T2DM patients) and calculated a fibrosis-4 score (FIB-4) from data recorded between 2006 and 2019. Comorbidities were obtained by linkage with hospital data. The study population was subdivided by aetiology of LF (alcoholic, viral, metabolic). Associations between upper level of FIB-4 and demographic and clinical variables were evaluated separately for each group using robust Poisson models and presented as prevalence ratios. Nearly one-quarter (24%) of T2DM patients had some form of LF: viral (0.44%) and alcoholic (0.53%) forms were far less frequent than metabolic ones (22.7%). Only 1 out of 5 of these patients had a history of known cirrhosis. Age, male sex, duration of diabetes, coronary disease, hyperuricemia, renal failure, and features of liver failure (e.g., lower body-mass index, lipid and HbA1c levels) were positively associated with metabolic LF. More intensive treatments with insulin and segretagogue emerged as a significant predictive indicators of LF of metabolic origin.

CONCLUSION

A sizeable proportion of T2DM patients has some degree of LF, mainly of metabolic origin and often undiagnosed. There is a need to clarify whether the link between insulin therapy and advanced LF is causal or not.

Non-Invasive Assessment of Liver Fibrosis and Steatosis in End-Stage Renal Disease Patients Undergoing Renal Transplant Evaluation

Background

Non-alcoholic fatty liver disease (NAFLD) has an increased prevalence in end-stage renal disease (ESRD) due to similar risk factors. The aim of this study was to assess non-invasive testing including transient elastography (TE) for liver stiffness (LS), controlled attenuated parameter (CAP) for steatosis, Fibrosis-4 (FIB-4) score, aspartate aminotransferase (AST) to platelet ratio index (APRI) and NAFLD fibrosis score (NFS), for evaluation of NAFLD along with advanced fibrosis (AF) in patients with ESRD undergoing renal transplant evaluation.

Methods

Data were retrospectively collected within 12 weeks of TE. Primary outcomes were AF, defined by LS ≥ 9 kPa compared to APRI > 1.5, FIB-4 > 2.67, and NFS of 0.675, and ≥ 5% steatosis by CAP ≥ 263 dB/m compared to liver histology when available.

Results

A total of 171 patients were evaluated: mean age 56, 65% male, 36% obese, 47% had diabetes, 96% hypertension, and 56% dyslipidemia. Mean LS was 6.5 kPa with 21% having AF. Mean CAP was 232 dB/m, with 25% having steatosis. Those with AF were older with higher NFS. Those with steatosis were obese and had diabetes without higher LS or fibrosis scores. Only NFS was associated with LS ≥ 9 kPa. In those with liver histology, AF was associated with LS ≥ 9 kPa but not with APRI, FIB-4, or NFS.

Conclusions

Despite normal liver enzymes, non-invasive assessment via TE in ESRD patients exhibited high prevalence of AF and steatosis not detected by APRI or FIB-4 scores. This high prevalence was secondary to the common risk factors such as obesity and diabetes, among patients with NAFLD and ESRD.

Relationship between nonalcoholic fatty liver disease and chronic kidney disease could start in childhood

The relationship between nonalcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) has gained considerable scientific interest in adults over the past few years. However, this association has recently emerged in children. Several published studies have suggested a role for NAFLD as a risk factor for CKD from the earliest age, with a potential influence of the major NAFLD risk polymorphisms, resulting in an increased risk of both cardiovascular and metabolic diseases. In view of the progressive course and increased cardiometabolic risk closely related to NAFLD and CKD, we focused on the link between these diseases in childhood.

NAFLD and renal function in children: is there a genetic link?

Introduction: Over the past decades, a large amount of both adult and pediatric data has shown relationship between Nonalcoholic Fatty Liver Disease (NAFLD) and chronic kidney disease (CKD), resulting in an overall increased cardiometabolic burden. In view of the remarkable role of the genetic background in the NAFLD pathophysiology, a potential influence of the major NAFLD polymorphisms (e.g. the I148M variant of the Patatin-like phospholipase containing domain 3 (PNPLA3) gene, the E167K allele of the Transmembrane 6 superfamily member 2 (TM6SF2), the hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13), and the Membrane bound O-acyltransferase domain containing 7-transmembrane channel-like 4 (MBOAT7-TMC4) genes) on renal function has been supposed. A shared metabolic and proinflammatory pathogenesis has been hypothesized, but the exact mechanism is still unknown.Areas covered: We provide a comprehensive review of the potential genetic link between NAFLD and CKD in children. Convincing both adult and pediatric evidence supports this association, but there is some dispute especially in childhood.Expert opinion: Evidence supporting a potential genetic link between NAFLD and CKD represents an intriguing aspect with a major clinical implication because of its putative role in improving strategy programs to counteract the higher cardiometabolic risk of these patients.

Elevated Fatty Liver Index Is Independently Associated With New Onset of Hypertension During a 10-Year Period in Both Male and Female Subjects

Background

Fatty liver index (FLI), a predictor of nonalcoholic fatty liver disease, has been reported to be associated with several metabolic disorders. Because of a sex difference in FLI level, we hypothesized that FLI is associated with development of hypertension to a greater extent in men or women.

Methods and Results

We investigated the relationship between FLI and development of hypertension during a 10‐year period in a general population of subjects who received annual health examinations (n=28 990). After exclusion (44.9%) of subjects with missing data and those with hypertension at baseline, a total of 15 965 subjects (men/women: 9466/6499) were included. FLI level was significantly higher in men than in women. During the 10‐year period, 2304 men (24.3%) and 745 women (11.5%) had new onset of hypertension. Multivariable Cox proportional hazard models with a restricted cubic spline showed that the hazard ratios (HRs) for development of hypertension after adjustment of age, systolic blood pressure, estimated glomerular filtration rate, habits of smoking and alcohol drinking, family history of hypertension, and diagnosis of diabetes mellitus and dyslipidemia increased gradually with increase in FLI in men and increased rapidly and then slowly with increase in FLI in women. There was a significant interaction between FLI and sex for the risk of hypertension in all of the subjects (P=0.049). The addition of FLI to traditional risk factors significantly improved the discriminatory capability.

Conclusions

A high level of FLI predicts the development of hypertension in both men and women, although distribution patterns of HRs were different between sexes.

Liver-spleen axis in nonalcoholic fatty liver disease

Introduction: NAFLD is often under-diagnosed, even though rates of its co-morbidities such as obesity and type2 diabetes mellitus, prominent statuses of inflammation, are significantly high. The spleen-liver axis is gaining much credit in the last years like other well-known organ axes.Areas covered: PubMed/MEDLINE was searched for relevant articles related to concomitant occurrence of NAFLD and spleen. Areas covered in this review include: (1) updated findings of spleen dimensions at ultrasonography, (2) discussion of current data on pathophysiological connections between obesity-related NAFLD and increased volume of the spleen, and (3) analysis of current immune-mediated mechanisms characterizing the so.called chronic low-grade inflammation leading to insulin resistance.Expert opinion: The advances in explaining mechanisms underlying the spleen involvement in immune regulation, coupled with research about the role of spleen in NAFLD, could impact real world outcomes through establishing better tools for a precocious diagnosis. Using both liver and spleen ultrasonography, technique largely dealt with in this review, could expand the possibility to cover an adequate diagnostic path toward NAFLD, reaching a good sensibility and specificity.

The Association between Decreased Kidney Function and FIB-4 Index Value, as Indirect Liver Fibrosis Indicator, in Middle-Aged and Older Subjects

Liver fibrosis might be linked to the prevalence of chronic kidney disease (CKD). However, there is little information about the association between liver fibrosis and decreased kidney function in middle-aged and older subjects. We aimed to evaluate the influence of liver fibrosis on the incidence or prevalence of CKD stage 3–5 in a retrospective cross-sectional study (Study 1, n = 806) and a 6-year longitudinal study (Study 2, n = 380) of middle-aged and older subjects. We evaluated liver fibrosis using the Fibrosis-4 (FIB-4) index and kidney function using the estimated glomerular filtration rate (eGFR) of all subjects. All subjects were divided into four groups on the basis of their FIB-4 score quartiles (low to high). In the Jonckheere–Terpstra trend test of Study 1, the eGFR decreased significantly from the lowest group to the highest group (p < 0.001). The Kaplan–Meier survival curve in Study 2 showed that the cumulative prevalence of CKD stage 3–5 was higher in the third quartile than the other quartiles. Our results suggest that liver fibrosis could be a useful indicator for the prevalence of CKD, even within a relatively healthy population, although liver fibrosis was not an independent risk factor.

Liver fat content is independently associated with microalbuminuria in a normotensive, euglycaemic Chinese population: a community-based, cross-sectional study

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) is associated with microalbuminuria (MA) in patients with diabetes/pre-diabetes. Whether this association is mediated by blood glucose and blood pressure (BP) remains unclear. This study investigated whether liver fat content (LFC) was associated with MA in a normotensive and non-diabetic population.

DESIGN

A cross-sectional substudy.

SETTINGS

LFC was determined from the hepatic/renal echogenicity ratio at ultrasound. MA was defined as an albumin-to-creatinine ratio (ACR) of 30-300 µg/mg (early- morning urine sample). Multivariable logistic regression and receiver operating characteristic (ROC) curve analyses were used to evaluate LFC as a predictor of MA.

PARTICIPANTS

Between May 2010 and June 2011, this cross-sectional, community-based study enrolled residents from Shanghai (China), aged ≥40 years and with normal glucose tolerance and BP.

RESULTS

A total of 550 residents (median age, 57 years; 174 men) were enrolled and stratified according to LFC quartiles. ACR (p<0.001) and MA prevalence (p=0.012) increased across the LFC quartiles. Multivariable logistic regression showed that the OR for MA (per SD increase in LFC) was 1.840 (95% CI 1.173 to 2.887, p=0.008) after adjustment for potential confounders including age, gender, waist-hip ratio, blood urea nitrogen, systolic and diastolic BP, fasting blood glucose, postprandial glucose, low-density lipoprotein-cholesterol, triglycerides, high-density lipoprotein-cholesterol, total cholesterol, estimated glomerular filtration rate and lipid-lowering drugs. The ROC analysis revealed that the optimal LFC cut-off value for predicting MA was 6.82%.

CONCLUSION

LFC is independently associated with MA in normotensive, euglycaemic middle-aged and elderly Chinese individuals. Screening for MA in people with NAFLD might facilitate early intervention to minimise kidney disease risk.

Fatty liver index is independently associated with deterioration of renal function during a 10-year period in healthy subjects

A potential link between chronic kidney disease (CKD) and non-alcoholic fatty liver disease (NAFLD) has been suggested. We investigated the relationship between fatty liver index (FLI), a noninvasive and simple predictor of NAFLD, and the development of CKD defined as estimated glomerular filtration rate < 60 mL/min/1.73 m² or positive for urinary protein during a 10-year follow-up period in subjects who received annual health examinations (n = 28,890). After exclusion of CKD at baseline, a total of 14,163 subjects (male/female: 9077/5086) were recruited. During the 10-year period, 1458 males (16.1%) and 737 females (14.5%) had new onset of CKD. Multivariable Cox proportional hazard models with a restricted cubic spline showed that hazard ratios (HRs) of CKD development increased with a higher FLI at baseline in both males and females after adjustment of confounders. When divided by tertiles of FLI level at baseline (T1 ~ T3), the adjusted risk of CKD development in the T3 group (HR [95% confidence interval], male/female: 1.33 [1.16–1.54]/1.33 [1.08–1.63]) was significantly higher than that in both sexes in the T1 group as the reference. The addition of FLI into traditional risk factors significantly improved the discriminatory capability for predicting CKD. In conclusion, a high level of FLI predicts the development of CKD in both sexes in a general population.

Interplay between Heart Disease and Metabolic Steatosis: A Contemporary Perspective

The liver-heart axis is a growing field of interest owing to rising evidence of complex bidirectional interplay between the two organs. Recent data suggest non-alcoholic fatty liver disease (NAFLD) has a significant, independent association with a wide spectrum of structural and functional cardiac diseases, and seems to worsen cardiovascular disease (CVD) prognosis. Conversely, the effect of cardiac disease on NAFLD is not well studied and data are mostly limited to cardiogenic liver disease. We believe it is important to further investigate the heart-liver relationship because of the tremendous global health and economic burden the two diseases pose, and the impact of such investigations on clinical decision making and management guidelines for both diseases. In this review, we summarize the current knowledge on NAFLD diagnosis, its systemic manifestations, and associations with CVD. More specifically, we review the pathophysiological mechanisms that govern the interplay between NAFLD and CVD and evaluate the relationship between different CVD treatments and NAFLD progression.

Sub-chronic microcystin-LR renal toxicity in rats fed a high fat/high cholesterol diet

Microcystin-LR (MCLR) is a liver and kidney toxin produced by cyanobacteria. Recently, it was demonstrated that MCLR exposure drives the progression of high fat/high cholesterol (HFHC) induced nonalcoholic fatty liver disease (NAFLD) to a more severe state. NAFLD is also a risk factor for chronic kidney disease (CKD), and the current study investigated MCLR renal toxicity in the context of an HFHC diet. Sprague Dawley rats were fed either a control diet or an HFHC diet for 10 weeks. After 6 weeks of diet, animals were administered either vehicle, 10 μg/kg, or 30 μg/kg MCLR via intraperitoneal injection every other day for 4 weeks. HFHC diet alone increased the renal glomerular change histopathology score, and 30 μg/kg MCLR exposure increased this score in both the control group and the HFHC group. In contrast, 30 μg/kg MCLR caused greater proteinuria and cast formation and decreased protein phosphatase 1 and 2A protein expression in the HFHC group. Urinary excretion of KIM-1 increased, but albumin and tamm-horsfall protein did not change after MCLR exposure. The general concordance between KIM-1, polyuria, proteinuria, and renal casts after MCLR exposure suggests that proximal tubule cell damage contributed to these connected pathologies. The control group adapted to repeated MCLR exposure by increasing the urinary elimination of MCLR and its metabolites, whereas this adaptation was blunted in the HFHC group. These data suggest an HFHC diet may increase the severity of certain MCLR-elicited renal toxicities.

Evaluation and management of extrahepatic manifestations of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a multisystemic disease and a rapidly growing cause of chronic liver disease in children and adults worldwide. Diagnosis and management of extrahepatic manifestations of NAFLD, including cardiovascular disease (CVD), type 2 diabetes mellitus, metabolic syndrome, chronic kidney disease, obstructive sleep apnea, polycystic ovarian syndrome, hypothyroidism, psoriasis, and extrahepatic malignancy are crucial for the treatment of patients with NAFLD. The leading cause of death in NAFLD is primarily from CVD, followed by liver-related mortality, extrahepatic cancer, liver cancer, and diabetes-related mortality. Therefore, clinicians need to identify high-risk patients earlier in the disease course and be aware of the extrahepatic manifestations of NAFLD to improve liver disease outcomes. In this review, we focus on the monitoring and management of the extrahepatic manifestations of NAFLD.

Early Kidney Dysfunction in Metabolic-Associated Fatty Liver Disease: Is Transient Elastography Useful as a Screening Method?

INTRODUCTION

Increasing evidence suggests an association between metabolic-associated fatty liver disease (MAFLD) and CKD. Timely prediction of early kidney dysfunction (EKD) is thus essential in this population although a screening method is not stablished. We aimed to evaluate the role of transient elastography (TE) in predicting EKD in patients with MAFLD.

MATERIALS AND METHODS

A prospective cohort study that included patients with MAFLD scheduled for evaluation was performed between May 2019 and January 2020. Demographic, clinical, and laboratory data and TE parameters were prospectively obtained. EKD was defined as microalbuminuria (urinary albumin-to-Cr ratio 30-300 mg/g) and estimated glomerular filtration rate ≥60 mL/min/1.73 m2. Significant liver fibrosis was defined as liver stiffness measurement (LSM) ≥8.2 kPa.

RESULTS

Of the included 45 patients with MALFD, 53.3% were of female gender with mean age of 53.5 ± 10.9 years. EKD was found in 17.8% of patients. MAFLD patients with EKD were significantly more obese (BMI ≥30) (75.0 vs. 32.4%, p = 0.045) and had significantly higher LSM (8.5 ± 4.1 vs. 5.8 ± 2.2 kPa, p = 0.01). After adjustment of potential confounders for EKD, the presence of liver fibrosis remained a significant predictor of EKD, being associated with a 14.3-fold increased risk of EKD (p = 0.04). The optimal cutoff value of LSM to predict EKD was 6.1 kPa (sensitivity: 85.7%; specificity: 67.6%).

CONCLUSION

Significant liver fibrosis is associated with a significant increased risk of EKD in patients with MAFLD, regardless of other comorbidities. Higher levels of LSM, particularly >6.1 kPa, alert for timely identification of EKD and associated comorbidities, as well as their control, in order to prevent the development of CKD in the long term.

Total-body PET Imaging: A New Frontier for the Assessment of Metabolic Disease and Obesity

Obesity and associated metabolic syndrome are a global public health issue. Understanding the pathophysiology of this systemic disease is of critical importance for the development of future therapeutic interventions to improve clinical outcomes. The multiorgan nature of the pathophysiology of obesity presents a unique challenge. Total-body PET imaging, either static or dynamic, provides a vital set of tools to study organ crosstalk. The visualization and quantification of tissue metabolic kinetics with total-body PET in health and disease provides essential information to better understand disease physiology and potentially develop diagnostic and therapeutic modalities.

Association between Non-Alcoholic Fatty Liver Disease and Chronic Kidney Disease: A Cross-Sectional Study

It is unclear whether the link between non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) is mediated by common risk factors. We aimed to elucidate the association between NAFLD and CKD using propensity score (PS)-matched analysis. We assessed 3725 Japanese individuals, excluding those with hepatitis B or C infection and men and women who consumed >30 and >20 g/day of alcohol, respectively. Of these, we enrolled 1097 Japanese subjects with NAFLD diagnosed by ultrasonography and 1097 PS-matched subjects without NAFLD. The prevalence of CKD was higher in subjects with NAFLD than in those without NAFLD before PS matching, but there was no significant difference between these groups in terms of CKD prevalence after PS matching. There was no difference in the prevalence of CKD between those with and without NAFLD in the subgroup analyses. Logistic regression analysis demonstrated that obesity, hypertension, and hyperuricemia were independent predictors of CKD, but NAFLD was not independently associated with CKD. In subjects with NAFLD, obesity, hypertension, and hyperuricemia were independent predictors of CKD. Thus, the link between NAFLD and CKD may be mediated by common risk factors. We recommend screening for CKD when patients with NAFLD have the aforementioned comorbidities.

LASS2 regulates hepatocyte steatosis by interacting with NDUFS2/OXPHOS related proteins

LAG1 longevity assurance homolog 2 (LASS2), a highly conserved transmembrane protein, has been reported to be associated with nonalcoholic fatty liver disease (NAFLD). However, the effect of LASS2 on energy homeostasis and its mechanism remains unknown. In this study, we found lower expression levels of LASS2 in the livers of mice with liver steatosis induced by a high-fat diet (HFD) and free fatty acids (FFAs)-treated hepatocytes. In FFAs-treated Hepa1-6 cells and mouse primary hepatocytes (MPHs), LASS2 overexpression significantly decreased intracellular lipid content compared with the control cells. LASS2 overexpression also significantly upregulated lipolysis-related proteins, such as ATGL and HSL, and inhibited lipogenesis-related proteins, such as SREBP1 and FAS. In addition, the phosphorylation levels of AMPK and ACC increased significantly. On the contrary, LASS2 knockdown in FFAs-treated hepatocytes aggravated lipid accumulation via facilitating lipogenesis and inhibiting lipolysis. Further, co-IP and LC-MS analysis found that LASS2 might interacted with NDUFS2 to inhibit lipogenesis. The production of mitochondrial reactive oxygen species (mtROS) may be related to the interaction between LASS2 and NDUFS2. Collectively, we are the first time to showed that LASS2 might promote the phosphorylation of AMPK via mtROS produced by interaction with NDUFS2/OXPHOS, thus inhibiting lipogenesis.

Noninvasive indices for predicting nonalcoholic fatty liver disease in patients with chronic kidney disease

BACKGROUND

Data on clinical characteristics of nonalcoholic fatty liver disease (NAFLD) in patients with chronic kidney disease (CKD) are scarce. We investigated the clinical features and risk factors of NAFLD using noninvasive serum markers in CKD patients and attempted the temporal validation of a predictive model for CKD based on NAFLD.

METHODS

This retrospective cross-sectional study was conducted in a single tertiary center. We enrolled 819 CKD patients and evaluated the predictive performance of relevant clinical and laboratory markers for the presence of NAFLD in both derivation (data from 2011 to 2014, n = 567) and validation (data from 2015 to 2016, n = 252) groups.

RESULTS

In the derivation group, NAFLD was observed in 89 patients (15.7%; mean body mass index (BMI), 24.6 kg/m2; median estimated glomerular filtration rate (eGFR), 28.0 ml/min). BMI, hemoglobin, serum alanine aminotransferase, eGFR, and triglyceride-glucose index were used to derive a prediction model for the presence of NAFLD. Using the cutoff value of 0.146, the area under the receiver operating characteristic curve (AUROC) for the prediction of NAFLD was 0.850. In the validation group, NAFLD was observed in 51 patients (20.2%; mean BMI, 25.4 kg/m2; median eGFR, 36.0 ml/min). Using the same prediction model and cutoff value, the AUROC was 0.842. NAFLD prevalence in CKD patients was comparable to that in the general population, increasing over time.

CONCLUSIONS

Our model using BMI, renal function, triglyceride-glucose index, serum alanine aminotransferase, and hemoglobin accurately predicted the presence of NAFLD in CKD patients.