Metabolic associated fatty liver disease is a risk factor for chronic kidney disease

Clinical outcomes of MAFLD versus NAFLD: A meta-analysis of observational studies

IMPORTANCE

The recent change in terminology from nonalcoholic fatty liver disease (NAFLD) to metabolic dysfunction-associated fatty liver disease (MAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD) highlights the link between hepatic steatosis and metabolic dysfunction, taking out the stigmata of alcohol.

OBJECTIVE

We compared the effects of NAFLD and MAFLD definitions on the risk of overall and cardiovascular (CV) mortality, liver-related events (LRE), nonfatal CV events (CVE), chronic kidney disease (CKD), and extra-hepatic cancers (EHC).

DATA SOURCES AND STUDY SELECTION

We systematically searched four large electronic databases for cohort studies (published through August 2023) that simultaneously used NAFLD and MAFLD definitions for examining the risk of mortality and adverse CV, renal, or oncological outcomes associated with both definitions. In total, 21 eligible cohort studies were identified. Meta-analysis was performed using random-effects modelling.

RESULTS

Compared with those with NAFLD, individuals with MAFLD had significantly higher rates of overall mortality (random-effect OR 1.12, 95% CI 1.04-1.21, p = .004) and CV mortality (random-effect OR 1.15, 95% CI 1.04-1.26, p = .004), and a marginal trend towards higher rates of developing CKD (random-effect OR 1.06, 95% CI 1.00-1.12, p = .058) and EHC events (random-effect OR 1.11, 95% CI 1.00-1.23, p = .052). We found no significant differences in the risk LREs and nonfatal CVE between MAFLD and NAFLD. Meta-regression analyses identified male sex and metabolic comorbidities as the strongest risk factors related to the risk of adverse clinical outcomes in MAFLD compared to NAFLD.

CONCLUSIONS AND RELEVANCE

Individuals with MAFLD have higher rates of overall and CV mortality and higher rates of developing CKD and EHC events than those with NAFLD, possibly due to the dysmetabolic risk profile related to MAFLD.

Effects of weight loss on metabolic dysfunction-associated fatty liver disease in Japanese people: Non-alcoholic fatty liver disease in the Gifu area, longitudinal analysis study

AIM

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a major health concern. This cohort study aimed to evaluate the association between weight loss and remission of MAFLD in the Japanese population to aid the development of efficient treatment strategies.

METHODS

This retrospective cohort study was conducted at a Japanese health screening center. Participants included 3309 individuals diagnosed with baseline MAFLD between 2004 and 2016. Logistic regression analysis was used to assess the association between MAFLD remission from baseline to 5 years and weight change.

RESULTS

After 5 years, 671 participants achieved MAFLD remission. Weight loss was associated with MAFLD remission for every 1 kg of weight loss over 5 years; the odds ratio for MAFLD remission was 1.24 (95% CI 1.15-1.34) for participants with type 2 diabetes, 1.40 (95% CI 1.35-1.45) for overweight participants, and 1.51 (95% CI 1.33-1.72) for non-overweight participants with metabolic dysfunctions. The cutoff values for weight loss for MAFLD remission were 1.9 kg for all participants, 3.0 kg for participants with type 2 diabetes, 1.9 kg for overweight participants, and 0.8 kg for non-overweight participants with metabolic dysfunctions.

CONCLUSIONS

Among participants diagnosed with MAFLD, weight loss was associated with MAFLD remission regardless of the type of metabolic dysfunction in MAFLD. The results of this study may contribute to the development of novel approaches to achieve MAFLD remission.

Review on Kidney-Liver Crosstalk: Pathophysiology of Their Disorders

Kidney-liver crosstalk plays a crucial role in normal and certain pathological conditions. In pathologic states, both renal-induced liver damage and liver-induced kidney diseases may happen through these kidney-liver interactions. This bidirectional crosstalk takes place through the systemic conditions that mutually influence both the liver and kidneys. Ischemia and reperfusion, cytokine release and pro-inflammatory signaling pathways, metabolic acidosis, oxidative stress, and altered enzyme activity and metabolic pathways establish the base of this interaction between the kidneys and liver. In these concomitant kidney-liver diseases, the survival rates strongly correlate with early intervention and treatment of organ dysfunction. Proper care of a nephrologist and hepatologist and the identification of pathological conditions using biomarkers at early stages are necessary to prevent the complications induced by this complex and potentially vicious cycle. Therefore, understanding the characteristics of this crosstalk is essential for better management. In this review, we discussed the available literature concerning the detrimental effects of kidney failure on liver functions and liver-induced kidney diseases.

Metabolic-associated fatty liver disease: a selective review of pathogenesis, diagnostic approaches, and therapeutic strategies

Background

Metabolic associated fatty liver disease (MAFLD) is a novel terminology introduced in 2020 to provide a more accurate description of fatty liver disease associated with metabolic dysfunction. It replaces the outdated term nonalcoholic fatty liver disease (NAFLD) and aims to improve diagnostic criteria and tailored treatment strategies for the disease. NAFLD, the most prevalent liver disease in western industrialized nations, has been steadily increasing in prevalence and is associated with serious complications such as cirrhosis and hepatocellular carcinoma. It is also linked to insulin resistance syndrome and cardiovascular diseases. However, current studies on NAFLD have limitations in meeting necessary histological endpoints.

Objective

This literature review aims to consolidate recent knowledge and discoveries concerning MAFLD, integrating the diverse aspects of the disease. Specifically, it focuses on analyzing the diagnostic criteria for MAFLD, differentiating it from NAFLD and alcoholic fatty liver disease (AFLD), and exploring the epidemiology, clinical manifestations, pathogenesis, and management approaches associated with MAFLD. The review also explores the associations between MAFLD and other conditions. It discusses the heightened mortality risk associated with MAFLD and its link to chronic kidney disease (CKD), showing that MAFLD exhibits enhanced diagnostic accuracy for identifying patients with CKD compared to NAFLD. The association between MAFLD and incident/prevalent CKD is supported by cohort studies and meta-analyses.

Conclusion

This literature review highlights the importance of MAFLD as a distinct terminology for fatty liver disease associated with metabolic dysfunction. The review provides insights into the diagnostic criteria, associations with CKD, and management approaches for MAFLD. Further research is needed to develop more accurate diagnostic tools for advanced fibrosis in MAFLD and to explore the underlying mechanisms linking MAFLD with other conditions. This review serves as a valuable resource for researchers and healthcare professionals seeking a comprehensive understanding of MAFLD.

Steatotic liver disease, MASLD and risk of chronic kidney disease

With the rising tide of fatty liver disease related to metabolic dysfunction worldwide, the association of this common liver disease with chronic kidney disease (CKD) has become increasingly evident. In 2020, the more inclusive term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace the old term non-alcoholic fatty liver disease (NAFLD). In 2023, a modified Delphi process was led by three large pan-national liver associations. There was consensus to change the fatty liver disease nomenclature and definition to include the presence of at least one of five common cardiometabolic risk factors as diagnostic criteria. The name chosen to replace NAFLD was metabolic dysfunction-associated steatotic liver disease (MASLD). The change of nomenclature from NAFLD to MAFLD and then MASLD has resulted in a reappraisal of the epidemiological trends and associations with the risk of developing CKD. The observed association between MAFLD/MASLD and CKD and our understanding that CKD can be an epiphenomenon linked to underlying metabolic dysfunction support the notion that individuals with MASLD are at substantially higher risk of incident CKD than those without MASLD. This narrative review provides an overview of the literature on (a) the evolution of criteria for diagnosing this highly prevalent metabolic liver disease, (b) the epidemiological evidence linking MASLD to the risk of CKD, (c) the underlying mechanisms by which MASLD (and factors strongly linked with MASLD) may increase the risk of developing CKD, and (d) the potential drug treatments that may benefit both MASLD and CKD.

Weight Loss Improves Liver Dysfunction and Dipstick Proteinuria in Obesity: The Japan Specific Health Checkups Study

INTRODUCTION

Obesity and inappropriate lifestyle is the major risk factors for liver dysfunction and proteinuria. Nevertheless, previous studies have not described the differential impacts of body weight changes and lifestyle modification on already developed liver dysfunction and proteinuria.

METHODS

The original cohort was 933,490 individuals from the Japanese general population. In this investigation, we included 36,256 obese individuals with elevated levels of aspartate aminotransferase and/or alanine aminotransferase (≥31 IU/L) or positive proteinuria (+/- or more) in both the first and second years. Outcomes were the first normalization of these data defined as improvement in liver dysfunction and proteinuria. Times to outcomes were assessed using the Cox proportional hazards modeling for -1 kg/m2/year change in body mass index (BMI) changes in exercise and alcohol intake.

RESULTS

The multivariable-adjusted hazard ratio (HR) for incident improvement in liver dysfunction with BMI change -1.0 kg/m2/year was 1.07 (95% confidence interval [CI] 1.05-1.09) in obesity and that with improved proteinuria was 1.04 (95%CI 1.02-1.07). Compared to subjects without exercise habits, subjects who gained exercise habits exhibited a higher rate of improvement in liver dysfunction (HR 1.08; 95%CI 1.01-1.15) but not in proteinuria (HR 0.98; 95%CI 0.88-1.08). Compared to subjects with continuous alcohol intake habits, subjects who quit alcohol intake also showed a higher rate of improvement in liver dysfunction (HR 1.20; 95%CI 1.09-1.32).

CONCLUSIONS

This study suggested that weight loss greater than 1 kg/m2/year improves liver dysfunction and dipstick proteinuria in obesity. Particularly, liver dysfunction can be remedied by acquiring an exercise habit and quitting alcohol intake.

Risk factors for heart, cerebrovascular, and kidney diseases: evaluation of potential side effects of medications to control hypertension, hyperglycemia, and hypercholesterolemia

Background

Heart disease (HD), cerebrovascular disease (CBD), and kidney disease (KD) are serious diseases worldwide. These diseases constitute the leading causes of death worldwide and are costly to treat. An analysis of risk factors is necessary to prevent these diseases.

Data and Methods

Risk factors were analyzed using data from 2,837,334, 2,864,874, and 2,870,262 medical checkups obtained from the JMDC Claims Database. The side effects of medications used to control hypertension (antihypertensive medications), hyperglycemia (antihyperglycemic medications), and hypercholesterolemia (cholesterol medications), including their interactions, were also evaluated. Logit models were used to calculate the odds ratios and confidence intervals. The sample period was from January 2005 to September 2019.

Results

Age and history of diseases were found to be very important factors, and the risk of having diseases could be almost doubled. Urine protein levels and recent large weight changes were also important factors for all three diseases and made the risks 10%-30% higher, except for KD. For KD, the risk was more than double for individuals with high urine protein levels. Negative side effects were observed with antihypertensive, antihyperglycemic, and cholesterol medications. In particular, when antihypertensive medications were used, the risks were almost doubled for HD and CBD. The risk would be triple for KD when individuals were taking antihypertensive medications. If they did not take antihypertensive medications and took other medications, these values were lower (20%-40% for HD, 50%-70% for CBD, and 60%-90% for KD). The interactions between the different types of medications were not very large. When antihypertensive and cholesterol medications were used simultaneously, the risk increased significantly in cases of HD and KD.

Conclusion

It is very important for individuals with risk factors to improve their physical condition for the prevention of these diseases. Taking antihypertensive, antihyperglycemic, and cholesterol medications, especially antihypertensive medications, may be serious risk factors. Special care and additional studies are necessary to prescribe these medications, particularly antihypertensive medications.

Limitations

No experimental interventions were performed. As the dataset was comprised of the results of health checkups of workers in Japan, individuals aged 76 and above were not included. Since the dataset only contained information obtained in Japan and the Japanese are ethnically homogeneous, potential ethnic effects on the diseases were not evaluated.

An international Delphi consensus statement on metabolic dysfunction-associated fatty liver disease and risk of chronic kidney disease

BACKGROUND

With the rising global prevalence of fatty liver disease related to metabolic dysfunction, the association of this common liver condition with chronic kidney disease (CKD) has become increasingly evident. In 2020, the more inclusive term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace the term non-alcoholic fatty liver disease (NAFLD). The observed association between MAFLD and CKD and our understanding that CKD can be a consequence of underlying metabolic dysfunction support the notion that individuals with MAFLD are at higher risk of having and developing CKD compared with those without MAFLD. However, to date, there is no appropriate guidance on CKD in individuals with MAFLD. Furthermore, there has been little attention paid to the link between MAFLD and CKD in the Nephrology community.

METHODS AND RESULTS

Using a Delphi-based approach, a multidisciplinary panel of 50 international experts from 26 countries reached a consensus on some of the open research questions regarding the link between MAFLD and CKD.

CONCLUSIONS

This Delphi-based consensus statement provided guidance on the epidemiology, mechanisms, management and treatment of MAFLD and CKD, as well as the relationship between the severity of MAFLD and risk of CKD, which establish a framework for the early prevention and management of these two common and interconnected diseases.

The Role of Metabolic Dysfunction-Associated Fatty Liver Disease in Developing Chronic Kidney Disease: Longitudinal Cohort Study

BACKGROUND

The association between metabolic dysfunction-associated fatty liver disease (MAFLD) and chronic kidney disease (CKD) is unclear.

OBJECTIVE

This longitudinal cohort study aimed to test whether MAFLD plays an important role in the development of CKD.

METHODS

This cohort study included 41,246 participants who had undergone 3 or more health examinations from 2008 to 2015 at the People's Hospital of Guangxi Zhuang Autonomous Region, China. Participants were categorized into 2 groups according to whether they presented with or without MAFLD. The occurrence of new-onset CKD was stated as either an estimated glomerular filtration rate of <60 mL/min per 1.73 m² or a higher level of albuminuria during their follow-up appointment. The association between MAFLD and CKD was evaluated using a Cox regression method.

RESULTS

Of the 41,246 participants, 11,860 (28.8%) were diagnosed with MAFLD. Over the course of the 14-year follow-up (median 10.0 years), 5347 (13%) participants experienced a new incident of CKD (135.73 per 10,000 person-years). MAFLD was discovered as an important risk factor for new incidents of CKD (hazard ratio 1.18, 95% CI 1.11-1.26) by using the multivariable Cox proportional hazard regression model. When stratified by gender, the adjusted hazard ratio for the incidence of CKD in men and women with MAFLD were 1.16 (95% CI 1.07-1.26) and 1.32 (95% CI 1.18-1.48), respectively. According to the subgroup analysis results, after adjusting for confounding factors, the MAFLD-related CKD risk was greater in men aged <60 years (P_interaction=.001) and in those with combined dyslipidemia (P_interaction=.02), but this relationship was not found in women (all P_interaction>.05).

CONCLUSIONS

MAFLD plays an important role in the development of new incidents of CKD in the long run.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2200058543; https://www.chictr.org.cn/showproj.html?proj=153109.

The association between metabolic dysfunction-associated fatty liver disease and chronic kidney disease: A systematic review and meta-analysis

BACKGROUND AND AIMS

The term metabolic dysfunction-associated fatty liver disease (MAFLD) has been established to better define patients with fatty liver disease who also present with metabolic dysfunction. However, the association between MAFLD and chronic-kidney disease (CKD) remains elusive.

METHODS

. We conducted systematic literature searching across multiple databases-PubMed, EMBASE, Cochrane library, and Google Scholar up until June 9th, 2022. The main exposure was the diagnosis of MAFLD and nonalcoholic fatty liver disease (NAFLD) regardless of the diagnostic modalities being used. The outcome of interest was the prevalence or the incidence of CKD.

RESULTS

There were 355,886 subjects from 11 included studies with the period of follow up of 4.6-6.5 years. Meta-analysis of cross-sectional studies showed that MAFLD was associated with a higher prevalent CKD (OR 1.50, 95%CI [1.02-2.23]; test for overall effect Z = 2.04, p = 0.04; I² = 97.7%, p < 0.001) and incident CKD (adjusted HR 1.35, 95%CI [1.18-1.52]; test for overall effect Z = 15.47, p < 0.001; I² = 84.6%, p < 0.001) and did not vary between age, sex, comorbidities, study region, and follow-up duration. No difference in CKD prevalence was found between MAFLD and NAFLD patients. Significant liver fibrosis, but not steatosis in was associated with greater odds of developing CKD. More severe MAFLD was also associated with higher odds of developing CKD.

CONCLUSION

This present meta-analysis using a large population indicates a significant association between MAFLD and the prevalence and incidence of CKD.

Comparison between metabolic-associated fatty liver disease and nonalcoholic fatty liver disease: From nomenclature to clinical outcomes

As a result of the obesity epidemic, Nonalcoholic fatty liver disease (NAFLD) and its complications have increased among millions of people. Consequently, a group of experts recommended changing the term NAFLD to an inclusive terminology more reflective of the underlying pathogenesis; metabolic-associated fatty liver disease (MAFLD). This new term of MAFLD has its own disease epidemiology and clinical outcomes prompting efforts in studying its differences from NAFLD. This article discusses the rationale behind the nomenclature change, the main differences, and its clinical implications.

The Impact of COVID-19 Pandemic Lockdown on the Relationship between Pediatric MAFLD and Renal Function

BACKGROUND

Both direct and indirect effects of COVID-19 have been found in all age groups. In particular, adult data demonstrated significant changes in patients with chronic and metabolic disease (e.g., obesity, diabetes, chronic kidney disease (CKD), and metabolic associated fatty liver dysfunction (MAFLD)), while similar pediatric evidence is still limited. We aimed at investigating the impact of the COVID-19 pandemic lockdown on the relationship between MAFLD and renal function in children with CKD due to congenital abnormalities of the kidney and urinary tract (CAKUT).

METHODS

A total of 21 children with CAKUT and CKD ≥ stage 1 underwent a comprehensive evaluation within 3 months before and 6 months after the first Italian lockdown.

RESULTS

At follow-up, CKD patients with MAFLD presented higher BMI-SDS, serum uric acid, triglycerides, and microalbuminuria levels and lower eGFR levels than those without MAFLD (all p < 0.05). Higher ferritin and white blood cell concentrations were also found in patients with CKD diagnosed with MAFLD than peers without MAFLD (both p = 0.01). Compared to children without MAFLD, a higher delta of BMI-SDS, eGFR levels, and microalbuminuria levels was found in patients with MAFLD.

CONCLUSIONS

Due to the negative influence of the COVID-19 lockdown on cardiometabolic health in childhood, a careful management of children with CKD is warranted.

Metabolic dysfunction-associated fatty liver disease can significantly increase the risk of chronic kidney disease in adults with type 2 diabetes

AIMS

This study is to explore the relationship between metabolic dysfunction-associated fatty liver disease (MAFLD) and chronic kidney disease (CKD) among populations with type 2 diabetes through longitudinal cohort study.

METHODS

3,627 subjects who had received at least three health examinations between 2008 and 2015 were included. CKD was stated as subjects with an eGFR < 60 mL/min per 1·73 m2 or the occurrence of 2 or more proteinuria during their follow-up.

RESULTS

After median of 10·0 years follow up, 837 (23·1%) developed CKD (244·7 per 10,000 person-years; 95 % CI, 228.4 - 261·8). MAFLD ([HR] 1·46; 95 % CI 1·26-1·70, P < 0.001) acts as an important risk factor of developing CKD. After adjusting for confounding factors, this association was consistent (HR 1·30; 95 % CI 1·11-1·53, P < 0.001). In stratified analysis, subjects aged < 60 years were likely to have greater risk of MAFLD-related CKD (HR 1·58 and 1·03; 95 % CI 1·28-1·95 and 0·79-1·33, P < 0.001 in both cases, respectively).

CONCLUSIONS

The risk of developing CKD in type 2 diabetes adults with MAFLD was higher, especially if they are below 60 years old. This study underscores the importance of early prevention strategies for MAFLD to reduce the occurrence of CKD in type 2 diabetes adults.

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.

The Inter-Organ Crosstalk Reveals an Inevitable Link between MAFLD and Extrahepatic Diseases

Fatty liver is known to be associated with extra-hepatic diseases including atherosclerotic cardiovascular disease and extra-hepatic cancers, which affect the prognosis and quality of life of the patients. The inter-organ crosstalk is mediated by metabolic abnormalities such as insulin resistance and visceral adiposity. Recently, metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed as a new definition for fatty liver. MAFLD is characterized by the inclusion criteria of metabolic abnormality. Therefore, MAFLD is expected to identify patients at high risk of extra-hepatic complications. In this review, we focus on the relationships between MAFLD and multi-organ diseases. We also describe the pathogenic mechanisms of the inter-organ crosstalk.

Association of metabolic dysfunction-associated fatty liver disease, type 2 diabetes mellitus, and metabolic goal achievement with risk of chronic kidney disease

Background

Although type 2 diabetes mellitus (T2DM) plays a significant role in the association between metabolic dysfunction-associated fatty liver disease (MAFLD) and chronic kidney disease (CKD), how T2DM development and glycemic deterioration affect CKD and its renal function indicators, estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR), remains unknown. We aimed to assess the association between MAFLD, along with T2DM, and risk of CKD, and then evaluate the effect of metabolic goal achievement in MAFLD on the risk of CKD.

Methods

In this cross-sectional study, 5,594 participants were included. Multivariate logistic regression and linear regression were used to examine the association between MAFLD with its T2DM status and metabolic goal achievement and risk of CKD, as well as eGFR and UACR.

Results

The MAFLD group had a higher prevalence of CKD (16.2 vs. 7.6%, P < 0.001) than the non-MAFLD group. MAFLD was independently associated with an increased risk of CKD (odds ratio [OR]: 1.35, 95% CI: 1.09-1.67) and increased eGFR and UACR. Among the three MAFLD subtypes, only the T2DM subtype exhibited significant associations with increased risk of CKD (OR: 2.85, 95% CI: 2.24-3.63), as well as increased eGFR and UACR. Glycemic deterioration in MAFLD was dose-dependently associated with an increased risk of CKD (P-trend < 0.001). Achieved metabolic goals in MAFLD decreased the risk of CKD, eGFR, and UACR; MAFLD with 2 or 3 achieved metabolic goals was not significantly associated with the risk of CKD (OR: 0.81, 95% CI: 0.59-1.12) and albuminuria.

Conclusion

MAFLD was independently associated with an increased risk of CKD, as well as increased eGFR and UACR. This association is strongly driven by T2DM status. Glycemic deterioration in MAFLD was dose-dependently associated with an increased risk of CKD. Achieved metabolic goals in MAFLD decreased the risk of CKD by reducing the risk of albuminuria.

Global Prevalence and Clinical Characteristics of Metabolic-associated Fatty Liver Disease: A Meta-Analysis and Systematic Review of 10 739 607 Individuals

BACKGROUND AND AIMS

Metabolic-associated fatty liver disease (MAFLD) was proposed as a better definition of nonalcoholic fatty liver disease (NAFLD) to encompass the metabolic dysregulation associated with NAFLD. This redefinition challenges our understanding of the disease. Hence, this study sought to conduct an updated analysis of the prevalence, clinical characteristics, and associated factors of MAFLD, with a further sensitivity analysis done based on lean and nonobese MAFLD individuals.

METHODS

Medline and Embase databases were searched to include articles on MAFLD. Meta-analysis of proportions was conducted using the generalized linear mix model. Associating factors were evaluated in conventional pairwise meta-analysis with sensitivity analysis on lean and nonobese MAFLD.

RESULTS

From pooled analysis involving 3 320 108 individuals, the overall prevalence of MAFLD was 38.77% (95% CI 32.94% to 44.95%); 5.37% (95% CI 4.36% to 6.59%) and 29.78% (95% CI 26.06% to 33.79%) of lean and nonobese individuals, respectively, had MAFLD. Metabolic complications such as hypertension [odds ratio (OR) 2.63, 95% CI 1.85 to 3.74, P < 0.0001 and OR 2.03; 95% CI 1.74 to 2.38, P < 0.0001, respectively] and diabetes (OR 3.80, 95% CI 2.65 to 5.43, P < 0.0001 and OR 3.46, 95% CI 2.81 to 4.27, P < 0.0001, respectively) were found as significant associating factors associated with lean and nonobese MAFLD.

CONCLUSIONS

This meta-analysis supports previous studies in reporting MAFLD to affect more than a third of the global population. While exploration of the pathogenic basis of fatty liver disease without metabolic dysregulation is required, the emphasis on management of concomitant metabolic disease in MAFLD can improve multidisciplinary efforts in managing the complex disease.

MAFLD and CKD: An Updated Narrative Review

Accumulating evidence now indicates that non-alcoholic fatty liver disease (NAFLD), which is the most common chronic liver disease observed in clinical practice worldwide, is independently associated with an increased risk of incident chronic kidney disease (CKD). Given that NAFLD is linked to insulin resistance, obesity and type 2 diabetes mellitus, an international panel of experts have recently proposed a name change from NAFLD to metabolic associated fatty liver disease (MAFLD). Since the diagnostic criteria for NAFLD and MAFLD are different, observational studies assessing the potential concordance (or even superiority) of MAFLD, compared with NAFLD, in detecting patients at increased risk of hepatic and extra-hepatic complications (including CKD) are required. Hence, in the last two years, some observational studies have investigated the potential relationship between MAFLD and CKD. The result is that, at present, evidence regarding the concordance or even superiority of MAFLD, compared with NAFLD, in detecting patients at higher risk of CKD is still preliminary, although some data indicate that MAFLD identifies patients with CKD as accurately as NAFLD. In this narrative review, we will discuss: (a) the epidemiological evidence assessing the association between NAFLD and risk of incident CKD, (b) the epidemiological data investigating the association between MAFLD and risk of CKD and (c) the biological mechanisms underlying the association between NAFLD/MAFLD and CKD.

Effect of a High Protein, Low Glycemic Index Dietary Intervention on Metabolic Dysfunction-Associated Fatty Liver Disease: A Randomized Controlled Trial

Background:

Metabolic dysfunction-associated fatty liver disease (MAFLD) affects people at an increasingly younger age. The primary treatment for patients with MAFLD is diet-induced weight loss; however, excessive dieting is poorly effective.

Objectives

The aim of this trial was to evaluate whether a high protein and low glycemic index (HPLG) dietary intervention would result in improvement of controlled attenuation parameter (CAP) and related metabolic markers in MAFLD.

Methods

A 12-week controlled, parallel-group, randomized intervention trial was performed. A number of 63 participants with MAFLD were enrolled and randomized between the HPLG dietary group and the balanced diet control group. Both diets had the same hypocaloric level and were prescribed ad libitum within food limit lists. The primary outcome was CAP. The main secondary outcomes were weight loss and improvement of metabolism-related indexes at week 12 after the program initiation.

Results

A total of 59 participants completed the intervention and were included in the final analysis. The mean age was 39.3 ± 8.9 years and 66.1% were men. In this trial, protein and carbohydrate intakes were significantly higher and lower, respectively, in the HPLG group compared to controls (p < 0.001). At week 12, CAP was significantly reduced in both groups (p < 0.001). However, a significantly greater reduction in liver fat was observed in the HPLG group compared to the control group (p = 0.011), with mean relative reductions of 30.90 dB/m (95% CI, 21.53 to 40.26, p < 0.001) and 15.43 dB/m (95% CI, 7.57 to 23.30, p < 0.001), respectively. From baseline to week 12, a significantly greater loss in bodyweight was recorded in participants in the HPLG group (6.52 kg; 95% CI, 5.50 to 7.54, p < 0.001) compared to control subjects (2.00 kg; 95% CI, 0.89 to 3.11, p = 0.001). Moreover, body fat percentage in the HPLG group was significantly reduced compared with the control group (p = 0.002). Within-group improvements in visceral fat, blood pressure, cardiovascular risk factors, and blood glucose-related indicators were detected in patients with MAFLD assigned to the HPLG diet (p < 0.05), but not in those prescribed the control diet (p > 0.05).

Conclusion

Under our experimental conditions, and compared to the traditional balanced diet, an HPLG diet led to a significant CAP remission, bodyweight or fat reduction, and improvement of metabolic markers in patients with MAFLD.

Clinical Trial Registration

ClinicalTrials.gov, identifier: NCT03972631.

Metabolic dysfunction-associated fatty liver disease: a year in review

PURPOSE OF REVIEW

In 2020, a novel comprehensive redefinition of fatty liver disease was proposed by an international panel of experts. This review aims to explore current evidence regarding the impact of this new definition on the current understanding of the epidemiology, pathogenesis, diagnosis, and clinical trials for fatty liver disease.

RECENT FINDINGS

The effectiveness of metabolic dysfunction-associated fatty liver disease (MAFLD) was compared to the existing criteria for nonalcoholic fatty liver disease (NAFLD). Recent data robustly suggest the superior utility of MAFLD in identifying patients at high risk for metabolic dysfunction, the hepatic and extra-hepatic complications, as well as those who would benefit from genetic testing, including patients with concomitant liver diseases. This change in name and criteria also appears to have improved disease awareness among patients and physicians.

SUMMARY

The transformation in name and definition from NAFLD to MAFLD represents an important milestone, which indicates significant tangible progress towards a more inclusive, equitable, and patient-centred approach to addressing the profound challenges of this disease. Growing evidence has illustrated the broader and specific contexts that have tremendous potential for positively influencing the diagnosis and treatment. In addition, the momentum accompanying this name change has included widespread public attention to the unique burden of this previously underappreciated disease.

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.

The clustering of Cardiovascular, Renal, Adipo-Metabolic Eye and Liver disease with type 2 diabetes

Type 2 diabetes is associated with an increased risk of cardiovascular disease, heart failure, chronic kidney disease, fatty liver disease, eye and foot disease. But equally, these conditions are associated with an increased risk of type 2 diabetes. Rather than being simply considered complications of diabetes, as exists within a 'pure' type 1 diabetes paradigm, both type 2 diabetes and its comorbidities are primarily caused by a failure to efficiently sequester excess energy leading to the accumulation of sick fat (adiposopathy). Type 2 diabetes is a symptom of a chronic disease complex, just as cardiovascular, renal, eye, foot and/or liver disease, are. In addition, each of these conditions feed forward so that dysfunction in one system accelerates dysfunction in another, partly through their shared pathogenesis and partly due dysfunction that follows in their wake. This review will explore the sticky, brittle conglomeration of CArdiac, Renal, Adipo-Metabolic, Eye and Liver disease (hereafter collectively known as CARAMEL disease) that is coincident in most patients with type 2 diabetes and contextualise the recent changes in diabetes guidelines that now specifically focus on identifying and aggressively managing these high-risk individuals with it.

Epidemiology, natural history, and diagnosis of metabolic dysfunction-associated fatty liver disease: a comparative review with nonalcoholic fatty liver disease

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) is the most common chronic liver disease worldwide - with an estimated global prevalence of 37%. Different from nonalcoholic fatty liver disease (NAFLD), which is an exclusion diagnosis, MAFLD is defined by a set of positive criteria. This recent change in terminology is challenging because MAFLD and NAFLD denote two similar, albeit not identical, clinical populations. When the diagnostic criteria for MAFLD are applied, liver histology appears more severe and clinical outcomes are less favorable. However, the clinical management of MAFLD and NAFLD remains similar. While liver biopsy is still the reference standard for achieving a final diagnosis, noninvasive imaging- or biomarker-based diagnostic modalities are currently gaining momentum. However, liver biopsy should be recommended when diagnostic challenges exist. In this review, we compared the epidemiology, natural history, and diagnosis of MAFLD with respect to the traditional NAFLD definition.