Histologic Scores for Fat and Fibrosis Associate With Development of Type 2 Diabetes in Patients With Nonalcoholic Fatty Liver Disease

Mediating effect of diabetes on the relationship between nonalcoholic fatty liver disease and atherosclerotic cardiovascular disease: a prospective cohort study

OBJECTIVE

This study explored the mediating effect of diabetes on the relationship between nonalcoholic fatty liver disease (NAFLD) and atherosclerotic cardiovascular disease (ASCVD).

METHODS

In this prospective community cohort study, 82 975 participants were enrolled, with the primary outcome being the incidence of new-onset ASCVD. Using the Cox proportional hazards model, the hazard ratio (HR) and 95% confidence interval (CI) for ASCVD occurrence were computed between NAFLD and non-NAFLD groups. The correlation between NAFLD and diabetes was assessed using a binary logistic regression model, and that between NAFLD, diabetes and ASCVD using a mediation model.

RESULTS

During follow-up, 9471 ASCVD cases were observed. Compared with individuals without NAFLD, those with NAFLD showed an increased ASCVD risk (HR: 1.424; 95% CI: 1.363-1.488; P < 0.001). Stratifying NAFLD based on metabolic subphenotypes revealed a higher ASCVD risk in the NAFLD combined with diabetes subgroup than in the non-NAFLD subgroup (HR: 1.960; 95% CI: 1.817-2.115; P < 0.001). NAFLD was positively associated with baseline diabetes (odds ratio: 2.983; 95% CI: 2.813-3.163; P < 0.001). Furthermore, NAFLD severity was positively correlated with diabetes risk. Mediation analysis indicated that diabetes partially mediated the effect of NAFLD on ASCVD incidence, accounting for 20.33% of the total effect.

CONCLUSION

NAFLD is an independent predictor of increased ASCVD risk, which may be slightly mediated by diabetes in patients with NAFLD. Evaluating NAFLD and diabetes may be crucial in the early screening and prevention of ASCVD.

Pathophysiological Relationship between Type 2 Diabetes Mellitus and Metabolic Dysfunction-Associated Steatotic Liver Disease: Novel Therapeutic Approaches

Type 2 diabetes mellitus (T2DM), often featuring hyperglycemia or insulin resistance, is a global health concern that is increasing in prevalence in the United States and worldwide. A common complication is metabolic dysfunction-associated steatotic liver disease (MASLD), the hepatic manifestation of metabolic syndrome that is also rapidly increasing in prevalence. The majority of patients with T2DM will experience MASLD, and likewise, individuals with MASLD are at an increased risk for developing T2DM. These two disorders may act synergistically, in part due to increased lipotoxicity and inflammation within the liver, among other causes. However, the pathophysiological mechanisms by which this occurs are unclear, as is how the improvement of one disorder can ameliorate the other. This review aims to discuss the pathogenic interactions between T2D and MASLD, and will highlight novel therapeutic targets and ongoing clinical trials for the treatment of these diseases.

Metabolic dysfunction-associated steatotic liver disease and diabetes: the cross-talk between hepatologist and diabetologist

INTRODUCTION

Metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes mellitus (DM) are the most prevalent metabolic disorders globally. The numbers affected in both disorders are also rapidly increasing with alarming trends in children and young adults.

AREAS COVERED

Insulin resistance (IR) and the subsequent metabolic dysregulation are the fundamental pathogenesis pathways of the prevalent metabolic disorders. The interaction and impacts are bidirectional between MASLD and DM in terms of disease mechanisms, disease course, risks, and prognosis. There's a pressing issue for highlighting the links between MASLD and DM for both care specialists and primary care providers. The review collected the scientific evidence addressing the mutual interactions between the two disorders. The strategies for surveillance, risk stratification, and management are discussed in a practical manner. It also provides individualized viewpoints of patient care in hepatology and diabetology.

EXPERT OPINION

Both MASLD and DM shared similar disease mechanisms, and affected the disease development and progression in a bidirectional manner. The high prevalence and the cross-link between the two disorders raise clinical issues from awareness, screening, risk stratification, optimal referral, to appropriate management for primary care providers.

LiverRisk score: An accurate, cost-effective tool to predict fibrosis, liver-related, and diabetes-related mortality in the general population

BACKGROUND

Noninvasive and early assessment of liver fibrosis is of great significance and is challenging. We aimed to evaluate the predictive performance and cost-effectiveness of the LiverRisk score for liver fibrosis and liver-related and diabetes-related mortality in the general population.

METHODS

The general population from the NHANES 2017-March 2020, NHANES 1999-2018, and UK Biobank 2006-2010 were included in the cross-sectional cohort (n = 3,770), along with the NHANES follow-up cohort (n = 25,317) and the UK Biobank follow-up cohort (n = 17,259). The cost-effectiveness analysis was performed using TreeAge Pro software. Liver stiffness measurements ≥10 kPa were defined as compensated advanced chronic liver disease (cACLD).

FINDINGS

Compared to conventional scores, the LiverRisk score had significantly better accuracy and calibration in predicting liver fibrosis, with an area under the receiver operating characteristic curve (AUC) of 0.76 (0.72-0.79) for cACLD. According to the updated thresholds of LiverRisk score (6 and 10), we reclassified the population into three groups: low, medium, and high risk. The AUCs of LiverRisk score for predicting liver-related and diabetes-related mortality at 5, 10, and 15 years were all above 0.8, with better performance than the Fibrosis-4 score. Furthermore, compared to the low-risk group, the medium-risk and high-risk groups in the two follow-up cohorts had a significantly higher risk of liver-related and diabetes-related mortality. Finally, the cost-effectiveness analysis showed that the incremental cost-effectiveness ratio for LiverRisk score compared to FIB-4 was USD $18,170 per additional quality-adjusted life-year (QALY) gained, below the willingness-to-pay threshold of $50,000/QALY.

CONCLUSIONS

The LiverRisk score is an accurate, cost-effective tool to predict liver fibrosis and liver-related and diabetes-related mortality in the general population.

FUNDING

The National Natural Science Foundation of China (nos. 82330060, 92059202, and 92359304); the Key Research and Development Program of Jiangsu Province (BE2023767a); the Fundamental Research Fund of Southeast University (3290002303A2); Changjiang Scholars Talent Cultivation Project of Zhongda Hospital of Southeast University (2023YJXYYRCPY03); and the Research Personnel Cultivation Program of Zhongda Hospital Southeast University (CZXM-GSP-RC125).

Diagnosis of hepatic steatosis and steatohepatitis in people with new-onset type 2 diabetes: a multidisciplinary approach

AIMS

Non-Alcoholic-Fatty-Liver-Disease (NAFLD) is the most common cause of chronic liver disease in Western countries; closely linked to obesity and type 2 diabetes (T2DM), it is an additional cardiovascular risk factor. The aim of this study is to investigate the prevalence of NAFLD at T2DM onset.

METHODS

122 newly diagnosed T2DM patients were enroled; NAFLD was diagnosed using ultrasound and fibrosis risk calculated with an FIB4-score. Intermediate and high-risk patients were referred to a hepatologist and underwent transient elastography (TE).

RESULTS

At T2DM diagnosis, 25% of patients were overweight, 47% were obese; ultrasound steatosis was present in 79% of patients; the average FIB-4 score was 1.4 (0.7). The NAFLD population was characterised by higher presence of obesity (60%, p 0.06); hypertension (56%, p 0.00); AST (26.3 (23.6) UI/L; p 0.00); ALT (49.3(41.0) UI/L p 0.00); FIB-4 score (1.6 (0.8); p 0.00). Among patients referred to a hepatologist, at TE, 65% had severe steatosis, 22% significant fibrosis and 25% advanced fibrosis.

CONCLUSION

This is the first proposal of a NAFLD screening model at T2DM diagnosis. The high prevalence of fibrosis found at the early stage T2DM confirms the compelling need for early management of NAFLD through cost-effective screening and long-term monitoring algorithms.

NAFLD Fibrosis Progression and Type 2 Diabetes: The Hepatic-Metabolic Interplay

The bidirectional relationship between type 2 diabetes and (non-alcoholic fatty liver disease) NAFLD is indicated by the higher prevalence and worse disease course of one condition in the presence of the other, but also by apparent beneficial effects observed in one, when the other is improved. This is partly explained by their belonging to a multisystemic disease that includes components of the metabolic syndrome and shared pathogenetic mechanisms. Throughout the progression of NAFLD to more advanced stages, complex systemic and local metabolic derangements are involved. During fibrogenesis, a significant metabolic reprogramming occurs in the hepatic stellate cells, hepatocytes, and immune cells, engaging carbohydrate and lipid pathways to support the high-energy-requiring processes. The natural history of NAFLD evolves in a variable and dynamic manner, probably due to the interaction of a variable number of modifiable (diet, physical exercise, microbiota composition, etc.) and non-modifiable (genetics, age, ethnicity, etc.) risk factors that may intervene concomitantly, or subsequently/intermittently in time. This may influence the risk (and rate) of fibrosis progression/regression. The recognition and control of the factors that determine a rapid progression of fibrosis (or its regression) are critical, as the fibrosis stages are associated with the risk of liver-related and all-cause mortality.

Understanding the Burden of Nonalcoholic Fatty Liver Disease: Time for Action

The prevalence of nonalcoholic fatty liver disease (NAFLD) in the United States is 38%, having increased by 50% within the past 3 decades. The estimated NAFLD prevalence among people with type 2 diabetes is 55-70%. The presence of type 2 diabetes is associated with a higher likelihood of progression of NAFLD to fibrosis development, liver transplant, and death. Cardiovascular disease is the main cause of mortality among people with NAFLD, and the risk of death is significantly higher in people with both NAFLD and type 2 diabetes. NAFLD carries high patient and economic burdens but low awareness among both the general public and health care providers. This article reviews the epidemiology of NAFLD and discusses the need for appropriate risk stratification, referral for specialty care, management of cardiometabolic risk factors, and treatment of the disease. The authors present a call to action to raise awareness of NAFLD and address its increasing burden in a systematic and efficient manner.

Clinical Classification of Obesity and Implications for Metabolic Dysfunction-Associated Fatty Liver Disease and Treatment

Obesity,and metabolic dysfunction-associated fatty liver disease (MAFLD) have reached epidemic proportions globally. Obesity and MAFLD frequently coexist and act synergistically to increase the risk of adverse clinical outcomes (both hepatic and extrahepatic). Type 2 diabetes mellitus (T2DM) is the most important risk factor for rapid progression of steatohepatitis and advanced fibrosis. Conversely, the later stages of MAFLD are associated with an increased risk of T2DM incident. According to the proposed criteria, MAFLD is diagnosed in patients with liver steatosis and in at least one in three: overweight or obese, T2DM, or signs of metabolic dysregulation if they are of normal weight. However, the clinical classification and correlation between obesity and MAFLD is more complex than expected. In addition, treatment for obesity and MAFLD are associated with a reduced risk of T2DM, suggesting that liver-based treatments could reduce the risk of developing T2DM. This review describes the clinical classification of obesity and MAFLD, discusses the clinical features of various types of obesity and MAFLD, emphasizes the role of visceral obesity and insulin resistance (IR) in the development of MAFLD,and summarizes the existing treatments for obesity and MAFLD that reduce the risk of developing T2DM.

Diet composition, nutrient substitutions and circulating fatty acids in relation to ectopic and visceral fat depots

BACKGROUND & AIMS

Short-term randomized trials have demonstrated that replacing saturated fat (SFA) with polyunsaturated fat (PUFA) causes a reduction or prevention of liver fat accumulation, but population-based studies on diet and body fat distribution are limited. We investigated cross-sectional associations between diet, circulating fatty acids and liver fat, visceral adipose tissue (VAT), intermuscular adipose tissue (IMAT) and other fat depots using different energy-adjustment models.

METHODS

Sex-stratified analyses of n = 9119 (for serum fatty acids) to 13 849 (for nutrients) participants in UK Biobank were conducted. Fat depots were assessed by MRI, circulating fatty acids by NMR spectroscopy and diet by repeated 24-h recalls. Liver fat, VAT and IMAT were primary outcomes; total adipose tissue (TAT) and abdominal subcutaneous adipose tissue (ASAT) were secondary outcomes. Three a priori defined models were constructed: the all-components model, standard model and leave-one-out model (main model including specified nutrient substitutions). Imiomics (MRI-derived) was used to confirm and visualize associations.

RESULTS

In women, substituting carbohydrates and free sugars with saturated fat (SFA) was positively associated with liver fat (β (95% CI) = 0.19 (0.02, 0.36) and β (95% CI) = 0.20 (0.05-0.35), respectively) and IMAT (β (95% CI) = 0.07 (0.00, 0.14) and β (95% CI) = 0.08 (0.02, 0.13), respectively), whereas substituting animal fat with plant fat was inversely associated with IMAT, ASAT and TAT. In the all-components and standard models, SFA and animal fat were positively associated with liver fat, IMAT and VAT whereas plant fat was inversely associated with IMAT in women. Few associations were observed in men. Circulating polyunsaturated fatty acids (PUFA) were inversely associated with liver fat, IMAT and VAT in both men and women, whereas SFA and monounsaturated fatty acids were positively associated.

CONCLUSIONS

Type of dietary fat may be an important determinant of ectopic fat in humans consuming their habitual diet. Plant fat and PUFA should be preferred over animal fat and SFA. This is corroborated by circulating fatty acids and overall consistent through different energy adjustment models.

TWITTER SUMMARY

In UK Biobank, intake of saturated- and animal fat were positively whereas biomarkers of polyunsaturated fat were inversely associated with liver-, visceral- and intermuscular fat. Type of dietary fat may be a determinant of ectopic fat, a risk factor for cardiometabolic disease.

Changing epidemiology, global trends and implications for outcomes of NAFLD

Non-alcoholic fatty liver disease (NAFLD) has rapidly become the most common liver disease globally and is currently estimated to affect 38% of the global population. Only a minority of patients with NAFLD will progress to cirrhosis or hepatocellular carcinoma, but from this vast population the total number of patients who are at risk of such severe outcomes is increasing. Worryingly, individuals are increasingly being affected by NAFLD at an earlier age, meaning there is more time for them to develop severe complications. With considerable changes in dietary composition and urbanisation, alongside the growth in obesity and type 2 diabetes in the global population, in particular in developing countries, the global proportion of persons affected by NAFLD is projected to increase further. Yet, there are large geographical discrepancies in the prevalence rates of NAFLD and its inflammatory component non-alcoholic steatohepatitis (NASH). Such differences are partly related to differing socio-economic milieus, but also to genetic predisposition. In this narrative review, we discuss recent changes in the epidemiology of NAFLD and NASH from regional and global perspectives, as well as in special populations. We also discuss the potential consequences of these changes on hepatic and extrahepatic events.

Greater Severity of Steatosis Is Associated with a Higher Risk of Incident Diabetes: A Retrospective Longitudinal Study

BACKGRUOUND

Fatty liver is associated with increased risk of developing type 2 diabetes. We aimed to evaluate whether the severity of hepatic steatosis is associated with incident diabetes.

METHODS

We conducted a longitudinal analysis using data from 1,798 participants who underwent a comprehensive health checkup and abdominal computed tomography (CT). We assessed the association between baseline liver attenuation value on non-contrast CT images and risk of incident diabetes. All the participants were categorized into three groups based on the baseline liver attenuation value on non-contrast CT images: without hepatic steatosis (>57 Hounsfield unit [HU]), mild hepatic steatosis (41-57 HU), and moderate to severe hepatic steatosis (≤40 HU).

RESULTS

During a median follow-up period of 5 years, 6.0% of the study participants progressed to diabetes. The incidence of diabetes was 17.3% in the moderate to severe hepatic steatosis group, 9.0% in the mild steatosis group, and 2.9% in those without hepatic steatosis. In a multivariate adjustment model, as compared with participants without hepatic steatosis, those with moderate to severe steatosis had a hazard ratio (HR) of 3.24 (95% confidence interval [CI], 1.64 to 4.2) for the development of diabetes, and those in the mild steatosis group had a HR of 2.33 (95% CI, 1.42 to 3.80). One standard deviation decrease in mean CT attenuation values of the liver was associated with a 40% increase in the development of diabetes (multivariate adjusted HR, 1.40; 95% CI, 1.2 to 1.63).

CONCLUSION

We found a positive association between severity of hepatic steatosis and risk of incident diabetes. Greater severity of steatosis was associated with a higher risk of incident diabetes.

Non-alcoholic fatty liver disease is associated with an increased risk of type 2 diabetes

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease worldwide and represents the leading cause of liver-related morbidity and mortality. Its all-cause mortality is often driven by co-existing metabolic diseases such as type 2 diabetes (T2DM), which share many pathophysiological characteristics. The risk of developing T2DM among NAFLD patients in Germany is only poorly described.

METHODS

A cohort of 17 245 NAFLD patients and a propensity score-matched cohort of equal size were identified from the Disease Analyzer database (IQVIA) between 2005 and 2020. The incidence of T2DM was evaluated as a function of NAFLD during a 5-year study period using Cox-regression models.

RESULTS

Within 5 years of the index date, 18.8% and 11.7% of individuals with and without NAFLD were diagnosed with T2DM ( P  < 0.001). Regression analysis revealed a hazard ratio of 1.77 [95% confidence interval (CI), 1.68-1.88] for the development of T2DM among NAFLD patients. Subgroup analyses confirmed this association for all age groups (18-50, 51-60, 61-70 and >70 years), male and female patients, as well as normal weight (BMI < 25 kg/m 2 ), overweighted (BMI 25-30 kg/m 2 ) and obese (BMI > 30 kg/m 2 ) patients.

CONCLUSION

Our data revealed a significantly increased incidence of T2DM among NAFLD patients in Germany. Given the dramatically increasing global relevance of NAFLD, we believe that prevention and regular screening programs for T2DM in NAFLD patients could help to reduce its high mortality and morbidity in the future.

MAFLD: a multisystem disease

Nonalcoholic fatty liver disease (NAFLD), affecting about 25% of general population and more than 50% of dysmetabolic patients, is an emerging cause of chronic liver disease and its complications. Recently, an international consensus of experts proposed to rename this disease as 'Metabolic dysfunction-Associated Fatty Liver Disease' (MAFLD) to focus on the bidirectional interplay between fatty liver and metabolic alterations and to stress the need of assessing fatty liver independently from alcohol consumption and other coexisting causes of liver disease. The peculiarity of NAFLD/MAFLD lies in the presence of a higher risk of not only - as expected - liver-related events but also of extrahepatic events, mostly cardiovascular and cancers. Available evidence suggests that these associations are not only the expression of sharing the same risk factors but shed light about the ability of NAFLD/MAFLD and particularly of its progressive form - nonalcoholic/metabolic dysfunction-associated steatohepatitis - to act as an independent risk factor via promotion of atherogenic dyslipidemia and a proinflammatory, profibrogenic, and procoagulant systemic environment. The present review summarizes available epidemiological and clinical evidence supporting the concept of NAFLD/MAFLD as a multisystemic disease, and highlights potential explanatory mechanisms underlying the association between NAFLD/MAFLD and extrahepatic disorders.

Fibrosis-4 stage of liver fibrosis predicts cardiovascular outcomes in acute coronary syndrome patients with and without type 2 diabetes mellitus

AIMS

We aim to analyze the effect of liver fibrosis, assessed by the Fibrosis-4 (FIB-4) index, on cardiovascular events in acute coronary syndrome (ACS) patients with and without type 2 diabetes mellitus (T2DM).

METHODS

6563 ACS patients undergoing PCI were analyzed in this study. Patients were divided into three groups according to literature-based FIB-4 cut-offs: < 1.45, 1.45-3.25, and ≥ 3.25.

RESULTS

During the median 2.4-year follow-up, 270 major adverse cardiac and cerebrovascular events (MACCE) and 194 major bleeding were recorded. Intermediate or high FIB-4 scores were significantly associated with an elevated risk of MACCE, mortality, and MI but not associated with ischemic stroke and major bleeding. Further restricted cubic spline analysis showed that FIB-4 as a continuous variable was positively associated with an increased adjusted risk of MACCE. The results were consistent in subgroups with and without T2DM.

CONCLUSIONS

Liver fibrosis staged by FIB-4 was correlated with an increased risk of MACCE, mortality, and MI in ACS patients who underwent PCI with and without T2DM. FIB-4 index may help risk stratification of ACS patients independent of T2DM status.

Risk for hepatic and extra-hepatic outcomes in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is defined by presence of steatosis in more than 5% of liver cells. The gold standard for diagnosis is liver biopsy, but this is seldom achieved due to costs and risk for side effects, and that is why the diagnosis is mostly made based on a combination of radiology and exclusion of other liver diseases. Disease severity staging can be noninvasively achieved with radiological exams such as elastography or blood-based markers that usually have lower sensitivity and specificity. NAFLD is today the most common chronic liver disease globally with a prevalence estimated to be 25%. Fortunately, for many persons NAFLD is an incidental finding with a good prognosis. Whilst a major focus has been on liver-related outcomes in NAFLD, there has recently been an increased interest in extrahepatic consequences of NAFLD. The most commonly studied outcomes include cardiovascular disease and cancer. The risk of adverse outcomes generally differs according to the baseline fibrosis stage. There is a five-time higher risk of liver-related events in NAFLD patients with fibrosis stage 3 as compared to those with no or little fibrosis. Meanwhile, the presence of nonalcoholic steatohepatitis (NASH) does not seem to influence prognosis in addition to fibrosis stage. Patients with NAFLD clearly have a higher risk for cardiovascular outcomes compared to the general population, with a recent meta-analysis indicating a 37% increased hazard for cardiovascular events as opposed to individuals without NAFLD. The risk of liver cancer is increased, which is mostly driven by presence of cirrhosis, but the increased risk is present also in patients without cirrhosis, and to a greater extent than for other chronic liver disease. Around one-third of patients with NAFLD and liver cancer do not have cirrhosis. Additionally, the risk of extrahepatic malignancies is thought to be moderately increased, with most evidence for a link between NAFLD and colorectal cancer where the risk is approximately 50% higher compared to patients without NAFLD. A particularly salient point is if NAFLD can be considered an independent risk factor for outcomes. Many studies have not been able to adjust for key confounders, or suffer from different forms of bias. The clinical problem is nevertheless to identify persons with an increased risk for adverse hepatic and extrahepatic outcomes. We here discuss the evidence linking NAFLD to severe hepatic and extrahepatic outcomes.

NADPH Oxidases Connecting Fatty Liver Disease, Insulin Resistance and Type 2 Diabetes: Current Knowledge and Therapeutic Outlook

Nonalcoholic fatty liver disease (NAFLD), characterized by ectopic fat accumulation in hepatocytes, is closely linked to insulin resistance and is the most frequent complication of type 2 diabetes mellitus (T2DM). One of the features connecting NAFLD, insulin resistance and T2DM is cellular oxidative stress. Oxidative stress refers to a redox imbalance due to an inequity between the capacity of production and the elimination of reactive oxygen species (ROS). One of the major cellular ROS sources is NADPH oxidase enzymes (NOX-es). In physiological conditions, NOX-es produce ROS purposefully in a timely and spatially regulated manner and are crucial regulators of various cellular events linked to metabolism, receptor signal transmission, proliferation and apoptosis. In contrast, dysregulated NOX-derived ROS production is related to the onset of diverse pathologies. This review provides a synopsis of current knowledge concerning NOX enzymes as connective elements between NAFLD, insulin resistance and T2DM and weighs their potential relevance as pharmacological targets to alleviate fatty liver disease.

The global NAFLD policy review and preparedness index: Are countries ready to address this silent public health challenge?

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent, yet largely underappreciated liver condition which is closely associated with obesity and metabolic disease. Despite affecting an estimated 1 in 4 adults globally, NAFLD is largely absent on national and global health agendas.

METHODS

We collected data from 102 countries, accounting for 86% of the world population, on NAFLD policies, guidelines, civil society engagement, clinical management, and epidemiologic data. A preparedness index was developed by coding questions into 6 domains (policies, guidelines, civil awareness, epidemiology and data, NAFLD detection, and NAFLD care management) and categorising the responses as high, medium, and low; a multiple correspondence analysis was then applied.

RESULTS

The highest scoring countries were India (42.7) and the United Kingdom (40.0), with 32 countries (31%) scoring zero out of 100. For 5 of the domains a minority of countries were categorised as high-level while the majority were categorised as low-level. No country had a national or sub-national strategy for NAFLD and <2% of the different strategies for related conditions included any mention of NAFLD. National NAFLD clinical guidelines were present in only 32 countries.

CONCLUSIONS

Although NAFLD is a pressing public health problem, no country was found to be well prepared to address it. There is a pressing need for strategies to address NAFLD at national and global levels.

LAY SUMMARY

Around a third of the countries scored a zero on the NAFLD policy preparedness index, with no country scoring over 50/100. Although NAFLD is a pressing public health problem, a comprehensive public health response is lacking in all 102 countries. Policies and strategies to address NAFLD at the national and global levels are urgently needed.

Advancing the global public health agenda for NAFLD: a consensus statement

Non-alcoholic fatty liver disease (NAFLD) is a potentially serious liver disease that affects approximately one-quarter of the global adult population, causing a substantial burden of ill health with wide-ranging social and economic implications. It is a multisystem disease and is considered the hepatic component of metabolic syndrome. Unlike other highly prevalent conditions, NAFLD has received little attention from the global public health community. Health system and public health responses to NAFLD have been weak and fragmented, and, despite its pervasiveness, NAFLD is largely unknown outside hepatology and gastroenterology. There is only a nascent global public health movement addressing NAFLD, and the disease is absent from nearly all national and international strategies and policies for non-communicable diseases, including obesity. In this global Delphi study, a multidisciplinary group of experts developed consensus statements and recommendations, which a larger group of collaborators reviewed over three rounds until consensus was achieved. The resulting consensus statements and recommendations address a broad range of topics - from epidemiology, awareness, care and treatment to public health policies and leadership - that have general relevance for policy-makers, health-care practitioners, civil society groups, research institutions and affected populations. These recommendations should provide a strong foundation for a comprehensive public health response to NAFLD.

Fatty liver index predicts incident risk of prediabetes, type 2 diabetes and non-alcoholic fatty liver disease (NAFLD)

AIMS

To investigate the association between overweight/obesity and fatty liver index (FLI) on the odds of incident prediabetes/type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) in 2020 participants after 10 years follow up.

METHODS

At baseline (in 2001) 2020 participants, males and females, aged 24-39 years, were stratified according to body mass index (BMI), normal weight (<25 kg/m2), overweight (≥25-<30 kg/m2), or obese (≥30 kg/m2) and FLI (as high FLI ≥60 or low FLI <60). We examined the incidence of prediabetes/type 2 diabetes and NAFLD (ultrasound assessed) over 10 years to 2011 to determine the relative impact of FLI and BMI.

RESULTS

514 and 52 individuals developed prediabetes and type 2 diabetes during follow-up. Such individuals were older, with higher BMI, serum glucose, insulin, alanine aminotransferase (ALT) and triglyceride (TG) concentrations than those who did not develop prediabetes or type 2 diabetes (n = 1454). The additional presence of high FLI significantly increased the risk of developing prediabetes and type 2 diabetes above the risk of being overweight/obese. Compared with normal weight, low FLI participants, the odds of prediabetes were ∼2-fold higher and the odds of type 2 diabetes were 9-10-fold higher respectively in the overweight/obese, high FLI group. No difference was observed between normal weight, low FLI and overweight/obese and low FLI groups.

CONCLUSIONS

An increased FLI significantly increases the odds of incident prediabetes, type 2 diabetes and NAFLD in individuals with overweight/obese highlighting the contributory role of liver fat accumulation in the pathophysiology of prediabetes/type 2 diabetes.Key messagesObesity is a risk factor for non-alcoholic fatty liver disease (NAFLD), prediabetes and type 2 diabetes.Additionally, NAFLD is more prevalent in people with prediabetes and type 2 diabetes when compared to age- and BMI-matched individuals.The presence of a raised fatty liver index (FLI) confers a significantly increased risk of developing prediabetes, type 2 diabetes and NAFLD above that conferred by being overweight/obese.The degree of elevation of FLI can risk stratify for incident prediabetes and type 2 diabetes in people with obesity.

Non-alcoholic fatty liver disease: A patient guideline

This patient guideline is intended for all patients at risk of or living with non-alcoholic fatty liver disease (NAFLD). NAFLD is the most frequent chronic liver disease worldwide and comes with a high disease burden. Yet, there is a lot of unawareness. Furthermore, many aspects of the disease are still to be unravelled, which has an important impact on the information that is given (or not) to patients. Its management requires a close interaction between patients and their many healthcare providers. It is important for patients to develop a full understanding of NAFLD in order to enable them to take an active role in their disease management. This guide summarises the current knowledge relevant to NAFLD and its management. It has been developed by patients, patient representatives, clinicians and scientists and is based on current scientific recommendations, intended to support patients in making informed decisions.

Defining comprehensive models of care for NAFLD

Non-alcoholic fatty liver disease (NAFLD) is now the leading cause of chronic liver disease globally. Despite the increased demand placed on health-care systems, little attention has been given to the design and implementation of efficient and effective models of care for patients with NAFLD. In many health-care settings, no formal pathways exist and, where pathways are in place, they are often not standardized according to good practices. We systematically searched the peer-reviewed literature with the aim of identifying published examples of comprehensive models of care that answered four key questions: what services are provided? Where are they provided? Who is offering them? How are they coordinated and integrated within health-care systems? We identified seven models of care and synthesized the findings into eight recommendations nested within the 'what, where, who and how' of care models. These recommendations, aimed at policy-makers and practitioners designing and implementing models of care, can help to address the increasing need for the provision of good practice care for patients with NAFLD.

The complex link between NAFLD and type 2 diabetes mellitus - mechanisms and treatments

Nonalcoholic fatty liver disease (NAFLD) has reached epidemic proportions worldwide. NAFLD and type 2 diabetes mellitus (T2DM) are known to frequently coexist and act synergistically to increase the risk of adverse (hepatic and extra-hepatic) clinical outcomes. T2DM is also one of the strongest risk factors for the faster progression of NAFLD to nonalcoholic steatohepatitis, advanced fibrosis or cirrhosis. However, the link between NAFLD and T2DM is more complex than previously believed. Strong evidence indicates that NAFLD is associated with an approximate twofold higher risk of developing T2DM, irrespective of obesity and other common metabolic risk factors. This risk parallels the severity of NAFLD, such that patients with more advanced stages of liver fibrosis are at increased risk of incident T2DM. In addition, the improvement or resolution of NAFLD (on ultrasonography) is associated with a reduction of T2DM risk, adding weight to causality and suggesting that liver-focused treatments might reduce the risk of developing T2DM. This Review describes the evidence of an association and causal link between NAFLD and T2DM, discusses the putative pathophysiological mechanisms linking NAFLD to T2DM and summarizes the current pharmacological treatments for NAFLD or T2DM that might benefit or adversely affect the risk of T2DM or NAFLD progression.

Incorporating fatty liver disease in multidisciplinary care and novel clinical trial designs for patients with metabolic diseases

With the global epidemics of obesity and associated conditions, including type 2 diabetes, metabolic dysfunction-associated fatty liver disease, chronic kidney disease, hypertension, stroke, cardiovascular disease, osteoporosis, cancer, and cognitive changes, the prevalence of multimorbidity is rapidly increasing worldwide. In this Review, a panel of international experts from across the spectrum of metabolic diseases come together to identify the challenges and provide perspectives on building a framework for a virtual primary care-driven, patient-centred, multidisciplinary model to deliver holistic care for patients with metabolic dysfunction-associated fatty liver disease and associated metabolic diseases. We focus on clinical care and innovative trial design for metabolic dysfunction-associated fatty liver disease and associated metabolic diseases. This work represents a call to action to promote collaboration and partnerships between stakeholders for improving the lives of people with, or at risk of, metabolic dysfunction-associated fatty liver disease and associated metabolic diseases.

Human and molecular genetics shed lights on fatty liver disease and diabetes conundrum

The causal role of abdominal overweight/obesity, insulin resistance and type 2 diabetes (T2D) on the risk of fatty liver disease (FLD) has robustly been proven. A consensus of experts has recently proposed the novel definition of 'metabolic dysfunction-associated fatty liver disease, MAFLD' instead of 'nonalcoholic fatty liver disease, NAFLD', emphasizing the central role of dysmetabolism in the disease pathogenesis. Conversely, a direct and independent contribution of FLD per se on risk of developing T2D is still a controversial topic. When dealing with FLD as a potential risk factor for T2D, it is straightforward to think of hepatic insulin resistance as the most relevant underlying mechanism. Emerging evidence supports genetic determinants of FLD (eg PNPLA3, TM6SF2, MBOAT7, GCKR, HSD17B13) as determinants of insulin resistance and T2D. However, recent studies highlighted that the key molecular mechanism of dysmetabolism is not fat accumulation per se but the degree of hepatic fibrosis (excess liver fat content-lipotoxicity), leading to reduced insulin clearance, insulin resistance and T2D. A consequence of these findings is that drugs that will ameliorate liver fat accumulation and fibrosis in principle may also exert a beneficial effect on insulin resistance and risk of T2D in individuals with FLD. Finally, initial findings show that these genetic factors might be directly implicated in modulating pancreatic beta-cell function, although future studies are needed to fully understand this relationship.

Established and emerging factors affecting the progression of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease affecting approximately 25% of the global population. Although a majority of NAFLD patients will never experience liver-related symptoms it is estimated that 5-10% will develop cirrhosis-related complications with risk of death or need for liver transplantation. NAFLD is closely associated with cardiovascular disease and components of the metabolic syndrome. However, NAFLD is not uncommon in lean individuals and may in these subjects represent a different entity with separate pathophysiological mechanisms involved implying a higher risk for development of end-stage liver disease. There is considerable fluctuation in the histopathological course of NAFLD that may partly be attributed to lifestyle factors and dietary composition. Nutrients such as fructose, monounsaturated fatty acids, and trans-fatty acids may aggravate NAFLD. Presence of type 2 diabetes mellitus seems to be the most important clinical predictor of liver-related morbidity and mortality in NAFLD. Apart from severity of the metabolic syndrome, genetic polymorphisms and environmental factors, such as moderate alcohol consumption, may explain the variation in histopathological and clinical outcome among NAFLD patients.

Nonalcoholic fatty liver disease and type 2 diabetes: pathophysiological mechanisms shared between the two faces of the same coin

The pathophysiological mechanisms underlying the close relationship between nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) are multiple, complex and only partially known. The purpose of this paper was to review the current knowledge of these mechanisms in a unified manner. Subjects with NAFLD and T2DM have established insulin resistance (IR), which exacerbates the two comorbidities. IR worsens NAFLD by increasing the accumulation of free fatty acids (FFAs) in the liver. This occurs due to an increase in the influx of FFAs from peripheral adipose tissue by the activation of hormone-sensitive lipase. In addition, there is de novo increased lipogenesis, a transcription factor, the sterols regulatory element-binding transcription factor 1c (SREBP-1c), which activates the expression of several genes strongly promotes lipogenesis by the liver and facilitate storage of triglycerides. Lipids accumulation in the liver induces a chronic stress in the endoplasmic reticulum of the hepatocytes. Genome-wide association studies have identified genetic variants associated with NAFLD severity, but unrelated to IR. In particular, the alteration of patatin-like phospholipase domain-containing protein 3 contributes to the susceptibility to NAFLD. Furthermore, the lipotoxicity of ceramides and diacylglycerol, well known in T2DM, triggers a chronic inflammatory process favoring the progression from hepatic steatosis to steatohepatitis. Reactive oxygen species produced by mitochondrial dysfunction trigger both liver inflammation and beta-cells damage, promoting the progression of both NAFLD and T2DM. The close association between NAFLD and T2DM is bidirectional, as T2DM may trigger both NAFLD onset and its progression, but NAFLD itself may contribute to the development of IR and T2DM. Future studies on the mechanisms will have to deepen the knowledge of the interaction between the two pathologies and should allow the identification of new therapeutic targets for the treatment of NAFLD, currently substantially absent.

Significant fibrosis predicts new-onset diabetes mellitus and arterial hypertension in patients with NASH

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) could play a catalytic role in the development of metabolic comorbidities, although the magnitude of this effect in metabolically healthy patients with NAFLD remains unclear. We assessed the role of biopsy-proven NAFLD on the risk of developing type 2 diabetes mellitus (T2DM) and other metabolic comorbidities (arterial hypertension [AHT], and dyslipidemia) in metabolically healthy patients.

METHODS

We included 178 metabolically healthy-defined by the absence of baseline T2DM, AHT, dyslipidemia-patients with biopsy-proven NAFLD from the HEPAmet Registry (N = 1,030). Hepamet fibrosis score (HFS), NAFLD fibrosis score, and Fibrosis-4 were calculated. Follow-up was computed from biopsy to the diagnosis of T2DM, AHT, or dyslipidemia.

RESULTS

During a follow-up of 5.6 ± 4.4 years, T2DM occurred in 9% (16/178), AHT in 8.4% (15/178), low HDL in 9.6% (17/178), and hypertriglyceridemia in 23.6% (42/178) of patients. In multivariate analysis, significant fibrosis predicted T2DM and AHT. Independent variables related to T2DM appearance were significant fibrosis (HR 2.95; 95% CI 1.19-7.31; p = 0.019), glucose levels (p = 0.008), age (p = 0.007) and BMI (p = 0.039). AHT was independently linked to significant fibrosis (HR 2.39; 95% CI 1.14-5.10; p = 0.028), age (p = 0.0001), BMI (p = 0.006), glucose (p = 0.021) and platelets (p = 0.050). The annual incidence rate of T2DM was higher in patients with significant fibrosis (4.4 vs. 1.2 cases per 100 person-years), and increased in the presence of obesity, similar to AHT (4.6 vs. 1.1 cases per 100 person-years). HFS >0.12 predicted the risk of T2DM (25% [4/16] vs. HFS <0.12 4.5% [4/88]; logRank 6.658, p = 0.010).

CONCLUSION

Metabolically healthy patients with NAFLD-related significant fibrosis were at greater risk of developing T2DM and AHT. HFS >0.12, but not NAFLD fibrosis score or Fibrosis-4, predicted the occurrence of T2DM.

LAY SUMMARY

Patients with biopsy-proven non-alcoholic fatty liver disease and significant fibrosis were at risk of developing type 2 diabetes mellitus and arterial hypertension. The risk of metabolic outcomes in patients with significant fibrosis was increased in the presence of obesity. In addition to liver biopsy, patients at intermediate-to-high risk of significant fibrosis by Hepamet fibrosis score were at risk of type 2 diabetes mellitus.

The amount of liver fat predicts mortality and development of type 2 diabetes in non-alcoholic fatty liver disease

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is a risk factor for development of type 2 diabetes mellitus (T2DM). We aimed to evaluate whether conventional histological grading of steatosis and accurate quantification of fat content in liver biopsies using stereological point counting (SPC) can predict mortality and future development of T2DM in NAFLD patients.

METHODS

129 patients with biopsy proven NAFLD, enrolled between 1988 and 1992, were re-evaluated on two occasions, after 13.7 (±1.5) and 23.2 (±6.8) years. In patients accepting to undergo the procedure, repeat liver biopsies were performed on each follow-up and were evaluated with conventional histopathological methodology and SPC.

RESULTS

Of the 106 patients without T2DM at baseline, 66 (62%) developed T2DM during a mean follow-up of 23.2 (± 6.8) years. Steatosis grade and liver fat measured with SPC independently (adjusted for age, BMI, fibrosis stage) predicted development of T2DM with an aHR of 1.60 per grade and 1.03 for each SPC percentage increase respectively. Overall mortality and development of T2DM was more common in patients with grade 3 steatosis compared to lower grades of steatosis. Liver fat measured with SPC was significant for overall mortality (aHR 1.04). In patients that underwent repeat biopsy, reduction in liver fat measured with SPC was associated with decreased risk of developing T2DM (aHR 0.91 for each SPC percentage decrease).

CONCLUSION

Steatosis grade and liver fat measured with SPC predict mortality and the risk of developing T2DM in NAFLD. Reduction in liver fat decreases the risk of developing T2DM.

Sexual Dimorphism of NAFLD in Adults. Focus on Clinical Aspects and Implications for Practice and Translational Research

Nonalcoholic fatty liver disease (NAFLD) embraces the clinico-pathological consequences of hepatic lipotoxicity and is a major public health problem globally. Sexual dimorphism is a definite feature of most human diseases but, under this aspect, NAFLD lags behind other medical fields. Here, we aim at summarizing and critically discussing the most prominent sex differences and gaps in NAFLD in humans, with emphasis on those aspects which are relevant for clinical practice and translational research. Sexual dimorphism of NAFLD is covered with references to the following areas: disease prevalence and risk factors, pathophysiology, comorbidities, natural course and complications. Finally, we also discuss selected gender differences and whether sex-specific lifestyle changes should be adopted to contrast NAFLD in men and women.

A Retrospective Population Study to Develop a Predictive Model of Prediabetes and Incident Type 2 Diabetes Mellitus from a Hospital Database in Japan Between 2004 and 2015

Background

Type 2 diabetes mellitus is a global public health problem. Prediabetes may be reversed by weight loss, diet, and lifestyle changes. However, without intervention, between 30–50% of individuals with prediabetes develop type 2 diabetes. This retrospective population study was conducted to develop a predictive model of prediabetes and incident type 2 diabetes mellitus using data from 2004 to 2015 from the DRYAD Japanese hospital database.

Material/Methods

A retrospective longitudinal population study was conducted using the DRYAD database from Murakami Memorial Hospital, Gifu, Japan, to construct a predictive model for prediabetes and incident type 2 diabetes mellitus in the population. Univariate analysis and multivariate analysis were performed to identify the variables that were associated with prediabetes. These variables were used to construct (75% samples) and verify (25% samples) the predictive model.

Results

From 2004 to 2015, a total of 11,113 cases were identified. Multivariate logistic regression analysis included the six variables of age, waist circumference, smoking history, the presence of fatty liver, fasting blood glucose (FBG), and glycated hemoglobin (HbA1c) level. Data were used to construct (75% samples) and verify (25% samples) in a predictive model. The area under the receiver operating characteristic (ROC) curve (AUC) of the predictive model was 0.87 (0.85–0.89) in the training cohort and 0.87 (0.86–0.90) in the validation cohort.

Conclusions

A prognostic model based on six variables was predictive for incident type 2 diabetes mellitus and prediabetes in a healthy population in Japan.

Non-alcoholic fatty liver disease as a cause and consequence of cardio-metabolic complications. Role of the ursodeoxicholic acid in the pharmacotherapy

The article presents an update of the role of non-alcoholic fatty liver disease (NAFLD) in cardiometabolic diseases and events: arterial hypertension and components of the metabolic syndrome. A review of NAFLD modern pharmacotherapy has been conducted. Particular attention is paid to the place of ursodeoxycholic acid in the complex treatment of NAFLD.

Hepatocellular carcinoma is the most common liver-related complication in patients with histopathologically-confirmed NAFLD in Japan

BACKGROUND

The incidence of liver-related events, cardiovascular events and type 2 diabetes mellitus in patients with histopathologically confirmed NAFLD remains unclear.

METHODS

We retrospectively investigated the incidence of liver events, cardiovascular events, malignancy, and type 2 diabetes mellitus in 402 Japanese patients with histopathologically confirmed NAFLD for a median follow-up of 4.2 years. We also investigated predictors of the development of hepatocellular carcinoma and type 2 diabetes mellitus in these patients.

RESULTS

The rate of liver-related events per 1000 person years was 4.17 (hepatocellular carcinoma, 3.67; hepatic encephalopathy, 1.60; esophago-gastric varices, 2.43; ascites, 0.80; and jaundice, 0.40). The rate of cardiovascular events and type 2 diabetes mellitus was 5.73 and 9.95, respectively. Overall mortality was 3.33 (liver-related events, 1.25; cardiovascular events, 0.42; and malignancies other than hepatocellular carcinoma, 0.83), in patients free of previous or current malignancies. Multivariate analyses identified old age (≥70 years) and advanced fibrosis stage 4 as significant determinants of hepatocellular carcinoma development, and hepatocyte steatosis (> 33%), female sex, and serum ferritin (≤80 μg/l) as significant determinants of type 2 diabetes mellitus development in these patients.

CONCLUSIONS

Our results highlighted the importance of cardiovascular and liver-related events in Japanese patients with histopathologically-confirmed NAFLD. Hepatocellular carcinoma was the most common liver-related event, and the incidence of hepatocellular carcinoma was more than half of that of cardiovascular events.

Steatohepatitis Is Not Associated with an Increased Risk for Fibrosis Progression in Nonalcoholic Fatty Liver Disease

Introduction

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease globally. The majority of NAFLD patients have fatty liver without inflammation (nonalcoholic fatty liver, NAFL), whereas a minority develop steatohepatitis (nonalcoholic steatohepatitis, NASH). Only NASH and not NAFL has been considered to increase the risk for fibrosis progression. The present study investigates risk factors for fibrosis progression in patients with NAFLD, and if fibrosis progression associates with subsequent mortality.

Material and Methods

All patients with at least two liver biopsies more than a year apart at our hospital between 1971 and 2016 were identified. Data on plausible risk factors for fibrosis progression were collected. Biopsies were scored for the presence of NASH and fibrosis stage. Regression models were used to investigate the association between baseline NASH and fibrosis progression and fibrosis progression with future mortality.

Results

60 patients had undergone serial biopsies (median interval between biopsies 8.4 years, range 1–33 years), with 26 patients (43%) having fibrosis progression. We found no significant risk factors for progression of fibrosis except time between biopsies. Among patients with fibrosis progression, 54% had NAFL and 46% had NASH at baseline. There was a trend for an association between fibrosis progression per se and increased mortality (hazard ratio 2.83, 95% CI 1.0–8.1, p = 0.05).

Conclusions

In this study on NAFLD, baseline steatohepatitis was not associated with an increased risk for fibrosis progression. NAFLD patients without steatohepatitis may develop progressive fibrosis, and those with progressive fibrosis appear to have a higher mortality risk irrespective of baseline NASH status.

Nonalcoholic Fatty Liver Disease and Risk of Incident Type 2 Diabetes: A Meta-analysis

OBJECTIVE

Several studies have explored the impact of nonalcoholic fatty liver disease (NAFLD) on risk of incident type 2 diabetes. However, the extent to which NAFLD may confer risk of incident diabetes remains uncertain. We performed a meta-analysis of relevant studies to quantify the magnitude of the association between NAFLD and risk of incident diabetes.

RESEARCH DESIGN AND METHODS

We collected data using PubMed, Scopus, and Web of Science from January 2000 to July 2017. We included only large (n ≥500) observational studies with a follow-up duration of at least 1 year in which NAFLD was diagnosed on imaging methods. Eligible studies were selected according to predefined keywords and clinical outcomes. Data from selected studies were extracted, and meta-analysis was performed using random-effects modeling.

RESULTS

A total of 19 observational studies with 296,439 individuals (30.1% with NAFLD) and nearly 16,000 cases of incident diabetes over a median of 5 years were included in the final analysis. Patients with NAFLD had a greater risk of incident diabetes than those without NAFLD (random-effects hazard ratio [HR] 2.22, 95% CI 1.84-2.60; I² = 79.2%). Patients with more "severe" NAFLD were also more likely to develop incident diabetes; this risk increased across the ultrasonographic scores of steatosis (n = 3 studies), but it appeared to be even greater among NAFLD patients with advanced high NAFLD fibrosis score (n = 1 study; random-effects HR 4.74, 95% CI 3.54-5.94). Sensitivity analyses did not alter these findings. Funnel plot and Egger test did not reveal significant publication bias. Study limitations included high heterogeneity, varying degrees of confounder adjustment across individual studies, and lack of studies using liver biopsy.

CONCLUSIONS

NAFLD is significantly associated with a twofold increased risk of incident diabetes. However, the observational design of the eligible studies does not allow for proving causality.

Hypertension, diabetes, atherosclerosis and NASH: Cause or consequence?

Non-alcoholic fatty liver disease (NAFLD) has become one of the most common forms of chronic liver disease worldwide and its prevalence is expected to continue rising. NAFLD has traditionally been considered a consequence of metabolic syndrome (MetS). However, the link between NAFLD and MetS components, especially type 2 diabetes mellitus (T2DM), hypertension (HTN), and cardiovascular disease (CVD) is more complex than previously thought. Indeed, the adverse effects of NAFLD extend far beyond the liver, with a large body of clinical evidence now suggesting that NAFLD may precede and/or promote the development of T2DM, HTN and atherosclerosis/CVD. The risk of developing these cardiometabolic diseases parallels the underlying severity of NAFLD. Accumulating evidence suggests that the presence and severity of NAFLD is associated with an increased risk of incident T2DM and HTN. Moreover, long-term prospective studies indicate that the presence and severity of NAFLD independently predicts fatal and nonfatal CVD events. In this review, we critically discuss the rapidly expanding body of clinical evidence that supports the existence of a bi-directional relationship between NAFLD and various components of MetS, particularly T2DM and HTN, as well as the current knowledge regarding a strong association between NAFLD and CVD morbidity and mortality. Finally, we discuss the most updated putative biological mechanisms through which NAFLD may contribute to the development of HTN, T2DM and CVD.

Natural History of NAFLD/NASH

Purpose of Review

The purpose of this review is to summarize the latest knowledge on the natural history of non-alcoholic fatty liver disease (NAFLD). The review focuses on mortality, liver-related complications, and histological course.

Recent Findings

Studies during the last decade have established NAFLD as a potentially progressive liver disease. Age and diabetes are the strongest clinical predictors of progressive disease. Fibrosis stage is the most important histological variable to predict mortality and liver-related complications. So far, no study has been able to show that non-alcoholic steatohepatitis at baseline predicts mortality or future liver-related complications when adjusting for fibrosis.

Summary

The outlines of the natural history of NAFLD have become clearer during the last decade. There is limited data on factors that predict clinical progression. Prospective longitudinal studies are needed to help us predict worse outcome in individual patients.