Can Alcoholic Liver Disease and Nonalcoholic Fatty Liver Disease Co-Exist?

Indian National Association for Study of the Liver (INASL) Guidance Paper on Nomenclature, Diagnosis and Treatment of Nonalcoholic Fatty Liver Disease (NAFLD)

Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease globally and in India. The already high burden of NAFLD in India is expected to further increase in the future in parallel with the ongoing epidemics of obesity and type 2 diabetes mellitus. Given the high prevalence of NAFLD in the community, it is crucial to identify those at risk of progressive liver disease to streamline referral and guide proper management. Existing guidelines on NAFLD by various international societies fail to capture the entire landscape of NAFLD in India and are often difficult to incorporate in clinical practice due to fundamental differences in sociocultural aspects and health infrastructure available in India. A lot of progress has been made in the field of NAFLD in the 7 years since the initial position paper by the Indian National Association for the Study of Liver on NAFLD in 2015. Further, the ongoing debate on the nomenclature of NAFLD is creating undue confusion among clinical practitioners. The ensuing comprehensive review provides consensus-based, guidance statements on the nomenclature, diagnosis, and treatment of NAFLD that are practically implementable in the Indian setting.

The NAFLD-MAFLD debate through the lens of the Arab world

The most common liver disease in the world is fatty liver disease related to metabolic dysfunction, yet neither patients nor medical professionals are fully aware of this. The disease, formerly known for decades as non-alcoholic fatty liver disease (NAFLD), has been renamed metabolic (dysfunction)-associated fatty liver disease (MAFLD), with many international consensus groups making recommendations on how the condition should be diagnosed and treated. This point of view explores the nomenclature change from the standpoint of Arab medical professionals and patients. The call for a name change brought up serious issues with the current nomenclature, which refers to the condition as NAFLD, and its diagnostic criteria, including the necessity for excluding alcohol consumption. The Arab world has its unique situation as regards both old and new nomenclatures. This is because of the low alcohol consumption rates in most Arab Muslim countries besides the reported high prevalence rates of obesity and its related comorbidities in the region. In our opinion, such unclarities acted as a significant roadblock to several crucial aspects of disease management in the Arab countries, including patient-doctor communication, patient awareness, partnership working, patient motivation to make lifestyle changes, and promotion of multiple health behavior changes. Many Arab world hepatologists thus wholeheartedly endorse this call to redefine the disease as they believe it will eventually positively impact the understanding and awareness of fatty liver disease, enhance patient treatment and quality of life, and reduce the load on the healthcare system.

The prevalence of alcoholic and nonalcoholic fatty liver disease in adolescents and young adults in the United States: analysis of the NHANES database

Background

The prevalence of fatty liver disease is potentially increasing in adolescents and young adults (AYAs) due to the obesity and alcohol pandemics. The aim of this study was to assess the prevalence of alcohol-associated fatty liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) in a representative U.S. cohort utilizing transient elastography to directly measure hepatic steatosis and suspected fibrosis.

Methods

AYAs (age 15–39 years) with valid FibroScan^® measurements in the National Health and Nutrition Examination Survey (NHANES) database (2017–2018) were included in the analyses. Those with viral hepatitis, pregnancy, or ALT/AST > 500 U/L were excluded. The population was divided into those with excessive alcohol consumption (ALQ130) and those without. Controlled attenuation parameter (CAP) score ≥ 248 dB/m was used to identify suspected ALD and NAFLD. In those with evidence of ALD, the following cutoffs of liver stiffness measurement (LSM) were used for suspected fibrosis: F ≥ F2 at LSM ≥ 7.5 kPa and F ≥ F3 at ≥ 9.5 kPa, respectively. In those with suspected NAFLD, the following LSM cutoffs were used: F ≥ F2 at 6.1 and F ≥ F3 at ≥ 7.1, respectively. Cutoffs were chosen based on published literature to maximize sensitivity.

Results

Comparing to those without, subjects with excessive alcohol consumption tended to be older (29.8 vs 28.5 years), have a higher BMI (29.3 vs 28.9 kg/m2), and be from a White ethnicity (65.3% vs. 55.4%). In subjects with excessive alcohol consumption, suspected ALD was present in 56.59% (95% CI 41.57–70.49). In those with suspected ALD, suspected significant fibrosis (F ≥ F2) was present in 12.3% (95% CI 4.74–28.34) and advanced fibrosis (F ≥ F3) was present in 6.31% (95% CI 0.69–39.55). Similarly, in subjects without excessive alcohol consumption, suspected NAFLD was present in 40.04% (36.64–43.54). In those with suspected NAFLD, suspected significant fibrosis (F ≥ F2) was present in 31.07% (27.25–35.16) and suspected advanced fibrosis (F ≥ F3) was present in 20.15% (16.05–24.99).

Conclusion

A significant percentage of AYAs are at risk for ALD and NAFLD and a subset of these subjects is at risk for significant fibrosis. Efforts should focus on increasing awareness of the prevalence of ALD and NAFLD in this population and to mitigate modifiable risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02430-7.

Comparing the Diagnostic Criteria of MAFLD and NAFLD in the Chinese Population: A Population-based Prospective Cohort Study

BACKGROUND AND AIMS

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new concept, proposed in 2020; however, its applicability in Asia populations has yet to be evaluated. Therefore, we aimed to compare the difference in epidemiological and clinical characteristics between MAFLD and non-alcoholic fatty liver disease (NAFLD) among Asian populations.

METHODS

Based on the Jinchang cohort, 30,633 participants were collected. The prevalence and incidence of MAFLD and NAFLD were used to analyze the epidemic characteristics and its overlapping effects. In addition, the corresponding clinical characteristics of the two diagnostic criteria populations were compared.

RESULTS

The prevalence rates of MAFLD and NAFLD were 21.03% and 18.83%, respectively. After an average 2.28-year follow-up, the incidence densities of MAFLD and NAFLD were 41.58 per 1,000 person-years and 37.69 per 1,000 person-years, respectively. With the increase of baseline age, body mass index (BMI), and waist circumference (WC) levels, the prevalence and incidence of MAFLD and NAFLD were on the rise (all p trend<0.05). Among the total patients diagnosed at baseline or follow-up, most patients had both MAFLD and NAFLD, accounting for 78.84% and 82.88%, respectively. Compared with NAFLD, MAFLD patients had greater proportions of males and metabolic diseases (diabetes, dyslipidemia), and had higher BMI, WC, liver enzymes, blood glucose, and lipid levels in the baseline diagnosis patients (p<0.05). Additionally, lean MAFLD patients had higher metabolic disorders than lean NAFLD patients (p<0.05).

CONCLUSIONS

Compared with NAFLD, the newly proposed definition of MAFLD is more practical and accurate, and it can help identify more fatty liver patients with high-risk diseases.

MAFLD Enhances Clinical Practice for Liver Disease in the Asia-Pacific region

Fatty liver is now a major cause of liver disease in the Asia-Pacific region. Liver diseases in this region have distinctive characteristics. First, fatty liver is frequently observed in lean/normal-weight individuals. However, there is no standard definition of this unique phenotype. Second, fatty liver is often observed in patients with concomitant viral hepatitis. The exclusion of viral hepatitis from non-alcoholic fatty liver disease limits its value and detracts from the investigation and holistic management of coexisting fatty liver in patients with viral hepatitis. Third, fatty liver-associated hepatocellular carcinoma (HCC) is generally categorized as non-B non-C HCC. Fourth, the population is aging rapidly, and it is imperative to develop a practicable, low-intensity exercise program for elderly patients. Fifth, most patients and non-specialized healthcare professionals still lack an awareness of the significance of fatty liver both in terms of intrahepatic and extrahepatic disease and cancer. Recently, an international expert panel proposed a new definition of fatty liver: metabolic dysfunction-associated fatty liver disease (MAFLD). One feature of MAFLD is that metabolic dysfunction is a prerequisite for diagnosis. Pertinent to regional issues, MAFLD also provides its diagnostic criteria in lean/normal-weight individuals. Furthermore, MAFLD is independent of any concomitant liver disease, including viral hepatitis. Therefore, MAFLD may be a more suitable definition for fatty liver in the Asia-Pacific region. In this review, we introduce the regional characteristics of fatty liver and discuss the advantages of MAFLD for improving clinical practice for liver disease in the region.

Experience With Changing Etiology and Nontransplant Curative Treatment Modalities for Hepatocellular Carcinoma in a Real-Life Setting-A Retrospective Descriptive Analysis

BACKGROUND

Hepatocellular carcinoma (HCC) has variable etiological risk factors. Radiofrequency ablation (RFA) and surgical resection (SR) are frequently used as curative treatment options. In the present study, we assessed the etiological factors and efficacy of RFA and SR in patients with unifocal HCC in a real-life setting.

METHODS

Of 870 patients with HCC seen over a period of nine years, 785 patients were assessed for stage and etiological risk factors. Of these, 110 (14%) patients with single HCC who were either treated with RFA (n = 72) or SR (n = 38) were evaluated for their outcomes in terms of overall survival (OS) and disease-free survival (DFS) over 3 years.

RESULTS

Of 785 patients [median age 60 (range 51-65) years, males (n = 685, 87.3%)] with HCC, viral hepatitis [HBV and HCV with or without alcohol = 502 (63.9%)] was the most common etiology; nonalcoholic steatohepatitis (NASH) and alcohol as an etiology showed increase over the years. About 677 (86.2%) patients had evidence of cirrhosis; NASH and HBV were predominant causes in noncirrhotic patients. Even though the groups were not matched, in 110 patients subjected to either RFA [mean tumor size, 2.2 (1.9-2.8) cm] or SR [mean tumor size, 7.1 (4.8-9.7) cm], tumor progression was observed in 49 (68%) and 16 (42%) patients in RFA and SR groups, respectively, with superior DFS in the SR group (P < 0.01). Of total 31 deaths, 20 (27.8%) deaths were in the RFA group and 11 (28.9%) in the SR group with no difference in OS at 3 years.

CONCLUSION

Viral hepatitis with or without alcohol is the commonest etiological factor for HCC in Northern India; NASH and alcohol are increasing over the years. In a real-life setting, in patients with unifocal HCC, there is no difference in overall 3-year survival subjected to SR or RFA with better DFS in the SR group.

Early-life exposure to alcohol and the risk of alcohol-induced liver disease in adulthood

Alcohol consumption remains prevalent among pregnant and nursing mothers despite the well-documented adverse effects this may have on the offspring. Moderate-to-high levels of alcohol consumption in pregnancy result in fetal alcohol syndrome (FAS) disorders, with brain defects being chief among the abnormalities. Recent findings indicate that while light-to-moderate levels may not cause FAS, it may contribute to epigenetic changes that make the offspring prone to adverse health outcomes including metabolic disorders and an increased propensity in the adolescent-onset of drinking alcohol. On the one hand, prenatal alcohol exposure (PAE) causes epigenetic changes that affect lipid and glucose transcript regulating genes resulting in metabolic abnormalities. On the other hand, it can program offspring for increased alcohol intake, enhance its palatability, and increase acceptance of alcohol's flavor through associative learning, making alcohol a plausible second hit for the development of alcohol-induced liver disease. Adolescent drinking results in alcohol dependence and abuse in adulthood. Adolescent drinking results in alcohol dependence and abuse in adulthood. Alterations on the opioid system, particularly, the mu-opioid system, has been implicated in the mechanism that induces increased alcohol consumption and acceptance. This review proposes a mechanism that links PAE to the development of alcoholism and eventually to alcoholic liver disease (ALD), which results from prolonged alcohol consumption. While PAE may not lead to ALD development in childhood, there are chances that it may lead to ALD in adulthood.

Nutrition in Chronic Liver Disease: Consensus Statement of the Indian National Association for Study of the Liver

Malnutrition and sarcopenia are common in patients with chronic liver disease and are associated with increased risk of decompensation, infections, wait-list mortality and poorer outcomes after liver transplantation. Assessment of nutritional status and management of malnutrition are therefore essential to improve outcomes in patients with chronic liver disease. This consensus statement of the Indian National Association for Study of the Liver provides a comprehensive review of nutrition in chronic liver disease and gives recommendations for nutritional screening and treatment in specific clinical scenarios of malnutrition in cirrhosis in adults as well as children with chronic liver disease and metabolic disorders.

Impact of metabolic risk factors on the severity and outcome of patients with alcohol-associated acute-on-chronic liver failure

BACKGROUND

Metabolic risk factors may impact the severity and outcome of alcoholic liver disease. The present study evaluated this effect in patients with alcohol-associated acute-on-chronic liver failure (ACLF).

METHODOLOGY

One thousand two hundred and sixteen prospectively enrolled patients with ACLF (males 98%, mean age 42.5 ± 9.4 years, mean CTP, MELD and AARC scores of 12 ± 1.4, 29.7 ± 7 and 9.8 ± 2 respectively) from the Asian Pacific Association for the Study of the Liver (APASL) ACLF Research Consortium (AARC) database were analysed retrospectively. Patients with or without metabolic risk factors were compared for severity (CTP, MELD, AARC scores) and day 30 and 90 mortality. Information on overweight/obesity, type 2 diabetes mellitus (T2DM), hypertension and dyslipidaemia were available in 1028 (85%), 1019 (84%), 1017 (84%) and 965 (79%) patients respectively.

RESULTS

Overall, 392 (32%) patients died at day 30 and 528 (43%) at day 90. Overweight/obesity, T2DM, hypertension and dyslipidaemia were present in 154 (15%), 142 (14%), 66 (7%) and 141 (15%) patients, respectively, with no risk factors in 809 (67%) patients. Patients with overweight/obesity had higher MELD scores (30.6 ± 7.1 vs 29.2 ± 6.9, P = .007) and those with dyslipidaemia had higher AARC scores (10.4 ± 1.2 vs 9.8 ± 2, P = .014). Overweight/obesity was associated with increased day 30 mortality (HR 1.54, 95% CI 1.06-2.24, P = .023). None of other metabolic risk factors, alone or in combination, had any impact on disease severity or mortality. On multivariate analysis, overweight or obesity was significantly associated with 30-day mortality (aHR 1.91, 95% CI 1.41-2.59, P < .001), independent of age, CTP, MELD and AARC scores.

CONCLUSION

Overweight/obesity and dyslipidaemia increase the severity of alcohol-associated ACLF, and the former also increases the short-term mortality in these patients.

What Are the Current Pharmacological Therapies for Nonalcoholic Fatty Liver Disease?

Of the currently available drugs tested to treat nonalcoholic fatty liver disease (NAFLD), the most efficacious drugs are pioglitazone (an insulin sensitizer) and vitamin E (an antioxidant). By targeting insulin resistance, the key pathogenic mechanism underlying metabolic syndrome and NAFLD, pioglitazone maybe the preferred drug to treat NAFLD. As we await the results of research trials into multiple new drugs to treat NAFLD, when should we use the currently available patients to treat NAFLD at the present time? To date, no drug has been approved by regulatory agency specifically to treat NAFLD. However, many drugs have been approved to treat other components of metabolic syndrome such as diabetes mellitus and dyslipidemia. Are we underutilizing the currently available drugs to treat NAFLD? Herein, we review the benefits and concerns of the use of these currently available drugs to treat NAFLD and suggest clinical scenarios, wherein the clinician should consider using these drugs.

cAMP Signaling in Pathobiology of Alcohol Associated Liver Disease

The importance of cyclic adenosine monophosphate (cAMP) in cellular responses to extracellular signals is well established. Many years after discovery, our understanding of the intricacy of cAMP signaling has improved dramatically. Multiple layers of regulation exist to ensure the specificity of cellular cAMP signaling. Hence, disturbances in cAMP homeostasis could arise at multiple levels, from changes in G protein coupled receptors and production of cAMP to the rate of degradation by phosphodiesterases. cAMP signaling plays critical roles in metabolism, inflammation and development of fibrosis in several tissues. Alcohol-associated liver disease (ALD) is a multifactorial condition ranging from a simple steatosis to steatohepatitis and fibrosis and ultimately cirrhosis, which might lead to hepatocellular cancer. To date, there is no FDA-approved therapy for ALD. Hence, identifying the targets for the treatment of ALD is an important undertaking. Several human studies have reported the changes in cAMP homeostasis in relation to alcohol use disorders. cAMP signaling has also been extensively studied in in vitro and in vivo models of ALD. This review focuses on the role of cAMP in the pathobiology of ALD with emphasis on the therapeutic potential of targeting cAMP signaling for the treatment of various stages of ALD.

Epidemiology of non-alcoholic and alcoholic fatty liver diseases

Liver diseases are fast emerging as global health priorities. Fatty liver is described in the setting of non-alcoholic fatty liver disease (NAFLD) as well as alcoholic liver disease (ALD), the pathogenesis of excess fat being different in the two conditions while both are important components of the changing face of burden of liver diseases worldwide. They are intimately associated with a globalized economy and an increasingly homogenous socio- cultural order with a westernized lifestyle. The accompanying adoption of a progressively sedentary life, consumption of diet dense in calories facilitate development of NAFLD while a spiraling upward trend in alcohol use along with earlier age of drinking as well as increased amount of per capita alcohol consumption increases the prevalence of ALD globally. Adverse health outcomes in NAFLD as well as ALD are caused not only by progressive liver fibrosis that is the most significant factor for liver related and all-cause mortality in both but also by non-liver (cardiovascular, cancer, accidents, neurological) clinical outcomes that calls for a multidisciplinary and social approach to these conditions. We present here an outline of facets of epidemiology of both NAFLD as well as ALD along with its' public health implications. A broad-based integrated approach that incorporates social, behavioral as well as biological targets need to be undertaken at a health system level in a planned manner for these evolving liver health priorities that disproportionately challenges the low- and middle-income countries of Asia, South America and Africa.

Genetic and lifestyle risk factors for advanced liver disease among men and women

BACKGROUND AND AIM

Liver disease is traditionally categorized as alcoholic and non-alcoholic. We studied various risk factors predictive of advanced non-viral liver disease in general population and analyzed the interaction between these factors and alcohol consumption.

METHODS

Persons without underlying liver disease who participated in the Health2000 or FINRISK studies 1992-2012 comprised a cohort of 41 260 individuals. Pattern of alcohol consumption and metabolic, lifestyle-related, and anthropometric parameters were analyzed with Cox regression analysis using severe liver disease hospitalization, cancer, or death as end-point. Viral liver diseases were excluded.

RESULTS

A total of 355 liver events occurred during the mean 12.4-year follow-up (511 789 person-years). In the multivariate model, age (hazard ratio [HR] 1.03, P = 0.0083 for men; HR 1.04, P = 0.0198 for women), waist-to-hip ratio (WHR) (HR 1.52, P = 0.0006 for men; HR 1.58, P = 0.0167 for women), patatin-like phospholipase-containing domain 3 mutations (HR 1.9, P = 0.024 for men; HR 2.7, P = 0.0109 for women), and weekly binge drinking (HR 2.4, P = 0.0024 for men; HR 7.4, P < 0.0001 for women) predicted development of severe liver disease. Among men, diabetes (HR 2.7, P = 0.0002), average alcohol consumption (HR for 10 g/day 1.1, P = 0.0022), non-married status (HR 1.9, P = 0.0397 for single; HR 2.4, P = 0.0002 for widowed/separated), and serum high-density lipoprotein (HR 2.2, P = 0.0022) and non-high-density lipoprotein cholesterol (HR 1.2, P = 0.0237) were additional risk factors. Alcohol intake increased the risk especially among persons with high WHR (P for interaction 0.009).

CONCLUSIONS

Age, patatin-like phospholipase-containing domain 3 haplotype, and WHR increase the risk for development of severe liver disease. We found strong synergism between alcohol and central obesity. Binge drinking is an additional risk factor.

Increased Serum Uric Acid over five years is a Risk Factor for Developing Fatty Liver

The prevalence of fatty liver disease (FLD) is increasing. To clarify risk factors for developing FLD, we analyzed a database from healthy Japanese adults who had annual medical check-ups in 2004 and reexamined in 2009. We used the fatty liver index (FLI) to classify participants as FLD (FLI ≥60), borderline FLD (30≤ FLI <60), and normal liver (FLI <30). Subjects with hepatitis B or C virus infection and subjects with FLD at the baseline were excluded. The cumulative incidence of FLD from normal liver and from borderline FLD over five years were 0.65% (52/8,025) and 12.9% (244/1,888), respectively. After multiple adjustments, higher serum uric acid (SUA) (OR:1.92; 95% CI:1.40–2.63) and increased SUA change (OR:3.734; 95% CI:2.57–5.42) became risk factors for developing FLD from normal liver, as well as younger age and higher body mass index. The risk factors for developing FLD from borderline FLD were similar. Not only higher baseline SUA but also increased SUA change became independent risks for developing FLD.