The effects of metabolic status on non-alcoholic fatty liver disease-related outcomes, beyond the presence of obesity

Rotating night shift work is associated with an increased risk of gastroesophageal reflux disease (GERD) symptoms among workers in China: A cross-sectional study

AIMS OF THE STUDY

Increasing studies suggest a significant association between night shift work and an increased risk of type 2 diabetes, obesity and other metabolic disorders. However, the available evidence of the association of rotating night shift work with gastroesophageal reflux disease (GERD) is limited. Herein, we hypothesised a link between the GERD risk and rotating night shift work among workers in China.

METHODS USED TO CONDUCT THE STUDY

A total of 2027 workers who completed a comprehensive health checkup were included. Logistic regression was used to investigate the link between rotating night shift work and the risk of GERD symptoms. Receiver operating characteristic (ROC) curve analysis was used to assess the multivariable model's diagnostic value for identifying GERD symptoms among workers.

RESULTS OF THE STUDY

In total, 556 (27.4%) individuals had GERD symptoms among 2027 workers. Multivariate analysis showed five independent factors for GERD: rotating night shift work (OR = 3.66, 95% CI: 2.52-5.40), age (OR = 2.53, 95% CI: 1.67-3.78), smoking (OR = 3.70, 95% CI: 2.63-5.21), Helicobacter pylori (H. pylori) infection (OR = 0.68, 95% CI: 0.48-0.96) and obesity (OR = 3.04, 95% CI: 2.43-3.83). A five-variable model based on five independent factors provided an area under a ROC curve (AUROC) of 0.80 (95% CI: 0.78-0.81) for identifying GERD symptoms among workers.

CONCLUSIONS DRAWN FROM THE STUDY AND CLINICAL IMPLICATIONS

Rotating night shift work is independently associated with an increased risk of GERD symptoms. Moreover a five-variable model (rotating night shift work, age, smoking, H pyori infection and obesity) can help identify individuals at high risk for GERD symptoms among workers in China.

From Nonalcoholic Fatty Liver Disease (NAFLD) to Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD)-New Terminology in Pediatric Patients as a Step in Good Scientific Direction?

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world, which predispose to more serious hepatic conditions. It ranges from simple liver steatosis to nonalcoholic steatohepatitis (NASH), which may progress to cirrhosis, and even end-stage liver disease. Since obesity became one of the most important health concerns wordwide, a considerable increase in the prevalance of NAFLD and other metabolic implications has been observed, both in adults and children. Due to the coexistence of visceral obesity, insulin resistance, dyslipidemia, NAFLD is considered to be the hepatic manifestation of metabolic syndrome (MetS). These relationships between NAFLD and MetS led to the set up in adults of a new term combining both of these conditions, called metabolic dysfunction-associated fatty liver disease (MAFLD). Based on these findings, we propose a set of criteria, which may be useful to diagnose MAFLD in children and adolescents.

Looking for a new name for non-alcoholic fatty liver disease in Spanish: esteatosis hepática metabólica (EHmet)

The name of a disease does not follow any defined protocol and the scientific community's acceptance of several variants based on the customs of every location is usual. There are examples of prevalent entities with curious naming processes, such as diabetes mellitus. The first word, "diabetes", comes from the Greek dia (through), be (to go), and tes (factor), while the second word, "mellitus", comes from Latin melli (honey). As a consequence, diabetes mellitus literally means "the sweet factor that goes through…", pertaining to an excessive and sweet diuresis. Thus, we could deduce that a definition representing exactly the pathophysiology of the particular disease is not required.

The metabolic profiles and body composition of lean metabolic associated fatty liver disease

BACKGROUND/PURPOSE

Metabolic associated fatty liver disease (MAFLD) is the commonest cause of chronic liver disease, which is associated with obesity and diabetes. However, it also occurs in lean individuals especially in Asian populations.

METHODS

The participants of Tzu Chi MAFLD cohort (TCMC) including health controls or MAFLD patients were enrolled. MAFLD was defined as fatty liver in imaging without hepatitis B virus, hepatitis C virus infection, drug, alcohol or other known causes of chronic liver disease. Lean MAFLD was defined as MAFLD in lean subjects (BMI < 23 kg/m²).

RESULTS

A total of 880 subjects were included for final analysis. Of 394 MAFLD patients, 65 (16.5%) patients were diagnosed as lean MAFLD. Lean MAFLD patients were elder, higher percentage of female gender, lower ALT, diastolic blood pressure, triglyceride, and waist circumference but higher HDL than non-lean MAFLD patients. Using binary regression analysis, elder age and lower waist circumference were associated with lean MAFLD. Compared with lean healthy controls, lean MAFLD patients had higher BMI, waist circumference, and percentage of hypertension. In body composition, fatty tissue index (FTI), lean tissue index (LTI) ,and total body water (TBW) were lower in lean MAFLD than non-lean MAFLD patients; but they were comparable with lean healthy controls.

CONCLUSIONS

The prevalence of lean MAFLD was 16.5% in this study population and it was higher in elder age, especially of female subjects. Lean MAFLD patients had different metabolic profiles compared with lean healthy controls, but different body composition compared with non-lean MAFLD patients.

The Association Between Different Obesity Phenotypes and Liver Fibrosis Scores in Elderly Individuals with Fatty Liver in Taiwan

PURPOSE

To examine the association between different phenotypes of obesity or metabolic syndromes and liver fibrosis score in a Taiwanese elderly population with fatty liver.

PATIENTS AND METHODS

This cross-sectional study included 1817 participants aged ≥65 years with fatty liver diagnosed by sonography. We used ethnicity-specific criteria for body mass index and metabolic syndrome, and to define obesity phenotypes as metabolically healthy non-obese (MHNO), metabolically unhealthy non-obese (MUNO), metabolically healthy obese (MHO), and metabolically unhealthy obese (MUO). Correlated fibrosis severity was calculated using the nonalcoholic fatty liver disease (NAFLD) fibrosis score (NFS) and Fibrosis-4 (FIB-4). Fibrosis severity was divided into two categories according to NFS (no-to-mild fibrosis and advanced fibrosis, defined as NFS ≤ 0.676 and >0.676, respectively) and FIB-4 score (no-to-mild fibrosis and advanced fibrosis, defined as FIB-4 score ≤2.67 and >2.67, respectively).

RESULTS

Compared with that in the MHNO group, the associated risk (odds ratio [OR], 95% confidence interval [CI]) of advanced fibrosis by NFS was 2.43 (1.50-3.93), 2.35 (1.25-4.41), and 6.11 (3.90-9.59), whereas that of advanced fibrosis by FIB-4 score was 1.34 (0.83-2.18), 2.37 (1.36-4.13), and 1.38 (0.82-2.31) in the MUNO, MHO, and MUO groups, respectively.

CONCLUSION

Both metabolic syndrome and obesity were positively associated with more advanced fibrosis according to NFS. The detrimental effect of obesity appears to be more than metabolic abnormalities per se in the elderly with more advanced fibrosis severity according to the FIB-4 score.

The Asian Pacific Association for the Study of the Liver clinical practice guidelines for the diagnosis and management of metabolic associated fatty liver disease

Metabolic associated fatty liver disease (MAFLD) is the principal worldwide cause of liver disease and affects nearly a quarter of the global population. The objective of this work was to present the clinical practice guidelines of the Asian Pacific Association for the Study of the Liver (APASL) on MAFLD. The guidelines cover various aspects of MAFLD including its epidemiology, diagnosis, screening, assessment, and treatment. The document is intended for practical use and for setting the stage for advancing clinical practice, knowledge, and research of MAFLD in adults, with specific reference to special groups as necessary. The guidelines also seek to improve patient care and awareness of the disease and assist stakeholders in the decision-making process by providing evidence-based data. The guidelines take into consideration the burden of clinical management for the healthcare sector.

Estimation of visceral fat is useful for the diagnosis of significant fibrosis in patients with non-alcoholic fatty liver disease

BACKGROUND

Obesity is a risk factor for non-alcoholic fatty liver disease (NAFLD), although obese patients with NAFLD do not always develop significant fibrosis. The distribution of body fat could predict the risk of NAFLD progression. 

AIM

To investigate the role of bioelectrical impedance-estimated visceral fat (VF) in assessing NAFLD severity.

METHODS

In this cross-sectional study, patients with biopsy-proven NAFLD were prospectively included. All patients underwent anthropometric evaluation, blood tests and bioelectrical impedance analysis.

RESULTS

Between 2017 and 2020, 119 patients were included [66.4% male, 56 years (SD 10.7), 62.2% obese, 61.3% with metabolic syndrome]. Sixty of them (50.4%) showed significant fibrosis (≥ F2) in liver biopsy. Age, VF and metabolic syndrome were associated with significant fibrosis (61 years vs 52 years, 16.4 vs 13.1, 73.3% vs 49.2%, respectively; P < 0.001 for all). In the multivariate analysis, VF and age were independently associated with significant fibrosis (VF, OR: 1.11, 95%CI: 1.02-1.22, P = 0.02; age, OR: 1.08, 95%CI: 1.03-1.12, P < 0.01). A model including these variables showed and area under the receiver operating characteristic curve (AUROC) of 0.75, which was not inferior to transient elastography or NAFLD fibrosis score AUROCs. We developed a nomogram including age and VF for assessing significant fibrosis in routine practice.

CONCLUSION

VF is a surrogate marker of liver fibrosis in patients with NAFLD. Bioelectrical impedance analysis is an inexpensive and simple method that can be combined with age to guide patient referral when other resources may be unavailable.

Serial Transient Elastography Examinations to Monitor Patients With Type 2 Diabetes: A Prospective Cohort Study

BACKGROUND AND AIMS

Type 2 diabetes is an important risk factor for nonalcoholic fatty liver disease (NAFLD) and advanced fibrosis. Current international guidelines recommend the use of noninvasive tests as initial assessments for NAFLD, but the role of noninvasive tests as monitoring tools has not been established. We aimed to study the role of transient elastography as a monitoring tool in patients with type 2 diabetes.

APPROACH AND RESULTS

We recruited patients with type 2 diabetes without viral hepatitis or excessive alcohol intake from a complication screening facility in Hong Kong in 2013-2014 and repeated the assessments in 2016-2018. The primary endpoint was an increase of liver stiffness measurement (LSM) to ≥10 kPa. The secondary endpoint was the change in the controlled attenuation parameter (CAP). A total of 611 patients with type 2 diabetes and a valid LSM (mean age, 57.7 ± 10.9 years; 342 men [56.0%]) were included in this study (568 also had a valid CAP). Overall, there was moderate correlation between the baseline and follow-up LSM (r = 0.689, P < 0.001). Among 487 patients with a baseline LSM <10 kPa, 21 (4.3%) had a follow-up LSM ≥10 kPa. Baseline body mass index, alanine aminotransferase (ALT), and ∆ALT were independent factors associated with LSM increase. Among 124 patients with a baseline LSM ≥10 kPa, 70 (56.5%) had a follow-up LSM <10 kPa. Among 198 patients with a CAP <248 dB/m at baseline, 103 (52.0%) had a CAP increased to ≥248 dB/m.

CONCLUSIONS

The prevalence and incidence of NAFLD in patients with type 2 diabetes are high. Although advanced fibrosis is common in this population, few patients progress to advanced fibrosis in 3 years. Future studies should define the optimal surveillance interval in patients with diabetes.

Bacterial antigen translocation and age as BMI-independent contributing factors on systemic inflammation in NAFLD patients

BACKGROUND & AIMS

Low-grade systemic inflammation is a crucial landmark in NAFLD favouring disease progression and comorbidities. We evaluated the input of circulating bacterial antigens on systemic markers of inflammation in NAFLD patients.

PATIENTS & METHODS

Multicenter cross-sectional study including consecutive patients with biopsy-proven NAFLD. Demographic, metabolic and fibrosis-related variables were collected. Circulating bacterial antigens were quantified in blood. Toll-like receptor SNPs were genotyped. Serum cytokine levels were evaluated. Peripheral blood mononuclear cell response to bacterial antigens was evaluated in vitro.

RESULTS

Three hundred and fifteen patients from five Spanish hospitals were distributed by BMI. At least, one bacterial antigenic type was found in 66 patients with BMI < 30 (63.4%) and 163 patients with BMI > 30 (77.3%) (P = .014). HOMA-IR was significantly higher in the presence of circulating antigens among patients with BMI < 30. NASH and significant fibrosis in non-obese patients were more frequent in the presence of at least two circulating antigenic types. Allelic frequencies of TLR variants were similar to controls and did not affect clinical or laboratory parameters. Pro-inflammatory cytokines were significantly increased in patients with bacterial antigens, regardless of BMI. TLR gene and protein expression levels were significantly increased in PBMCs from patients with bacterial antigens. Antigen concentrations independently influenced TNF-α and IL-6, in both BMI subgroups of patients. Age independently influenced TNF-α and IL-6 in non-obese patients, and TNF-α in obese patients.

CONCLUSION

Serum circulating bacterial antigens as well as age were BMI-independent factors related to increased systemic inflammation in NAFLD and provides insight on the multifaceted sources of inflammation in these patients.

Liver fibrosis score, physical frailty, and the risk of dementia in older adults: The Italian Longitudinal Study on Aging

INTRODUCTION

Liver fibrosis increases progressively with aging and has been associated with poorer cognitive performance in middle-aged and older adults. We investigated the relationships between a non-invasive score for advanced liver fibrosis (non-alcoholic fatty liver disease [NAFLD] fibrosis score [NFS]) and dementia risk. We also assessed physical frailty, a common geriatric condition which is associated to dementia. We tested the joint effects of physical frailty and fibrosis on dementia incidence.

METHODS

A total of 1061 older adults (65 to 84 years), from the Italian Longitudinal Study on Aging, were prospectively evaluated for the risk of dementia in a period between 1992 and 2001. Liver fibrosis was defined according to the NFS. Physical frailty was assessed according to the Fried's criteria. Cox proportional hazards models were used to estimate the short- and long-term risk of overall dementia, associated to the NFS, testing the effect modifier of physical frailty status.

RESULTS

Older adults with only high NFS (F3-F4) did not exhibit a significant increased risk of overall dementia. Over 8 years of follow-up, frail older adults with high NFS had an increased risk of overall dementia (hazard ratio [HR]: 4.23; 95% confidence interval [CI]: 1.22 to 14.70, P = .023). Finally, physically frail older adults with low albumin serum levels (albumin < 4.3 g/dL) and with advanced liver fibrosis (F3-F4 NFS) compared to those with lower liver fibrosis score (F0-F2 NFS) were more likely to have a higher risk of overall dementia in a long term-period (HR: 16.42; 95% CI: 1.44 to 187.67, P = .024).

DISCUSSION

Advanced liver fibrosis (F3-F4 NFS) could be a long-term predictor for overall dementia in people with physical frailty. These findings should encourage a typical geriatric, multidisciplinary assessment which accounts also for the possible co-presence of frail condition in older adults with chronic liver disease and liver fibrosis.

Global prevalence, incidence, and outcomes of non-obese or lean non-alcoholic fatty liver disease: a systematic review and meta-analysis

BACKGROUND

Although non-alcoholic fatty liver disease (NAFLD) is commonly associated with obesity, it is increasingly being identified in non-obese individuals. We aimed to characterise the prevalence, incidence, and long-term outcomes of non-obese or lean NAFLD at a global level.

METHODS

For this systematic review and meta-analysis, we searched PubMed, Embase, Scopus, and the Cochrane Library from inception to May 1, 2019, for relevant original research articles without any language restrictions. The literature search and data extraction were done independently by two investigators. Primary outcomes were the prevalence of non-obese or lean people within the NAFLD group and the prevalence of non-obese or lean NAFLD in the general, non-obese, and lean populations; the incidence of NAFLD among non-obese and lean populations; and long-term outcomes of non-obese people with NAFLD. We also aimed to characterise the demographic, clinical, and histological characteristics of individuals with non-obese NAFLD.

FINDINGS

We identified 93 studies (n=10 576 383) from 24 countries or areas: 84 studies (n=10 530 308) were used for the prevalence analysis, five (n=9121) were used for the incidence analysis, and eight (n=36 954) were used for the outcomes analysis. Within the NAFLD population, 19·2% (95% CI 15·9-23·0) of people were lean and 40·8% (36·6-45·1) were non-obese. The prevalence of non-obese NAFLD in the general population varied from 25% or lower in some countries (eg, Malaysia and Pakistan) to higher than 50% in others (eg, Austria, Mexico, and Sweden). In the general population (comprising individuals with and without NAFLD), 12·1% (95% CI 9·3-15·6) of people had non-obese NAFLD and 5·1% (3·7-7·0) had lean NAFLD. The incidence of NAFLD in the non-obese population (without NAFLD at baseline) was 24·6 (95% CI 13·4-39·2) per 1000 person-years. Among people with non-obese or lean NALFD, 39·0% (95% CI 24·1-56·3) had non-alcoholic steatohepatitis, 29·2% (21·9-37·9) had significant fibrosis (stage ≥2), and 3·2% (1·5-5·7) had cirrhosis. Among the non-obese or lean NAFLD population, the incidence of all-cause mortality was 12·1 (95% CI 0·5-38·8) per 1000 person-years, that for liver-related mortality was 4·1 (1·9-7·1) per 1000 person-years, cardiovascular-related mortality was 4·0 (0·1-14·9) per 1000 person-years, new-onset diabetes was 12·6 (8·0-18·3) per 1000 person-years, new-onset cardiovascular disease was 18·7 (9·2-31·2) per 1000 person-years, and new-onset hypertension was 56·1 (38·5-77·0) per 1000 person-years. Most analyses were characterised by high heterogeneity.

INTERPRETATION

Overall, around 40% of the global NAFLD population was classified as non-obese and almost a fifth was lean. Both non-obese and lean groups had substantial long-term liver and non-liver comorbidities. These findings suggest that obesity should not be the sole criterion for NAFLD screening. Moreover, clinical trials of treatments for NAFLD should include participants across all body-mass index ranges.

FUNDING

None.

Stratification of patients in NASH clinical trials: A pitfall for trial success

Identifying the most effective therapeutic intervention in patients with NAFLD is challenging. Precise stratification in clinical trials is key to ensuring the inclusion of patients who will benefit (and not those who will be harmed) and/or in whom the natural history can be improved. Clinical trials in NAFLD can provide useful information about the individual components that underlie this complex metabolic disorder and the concomitant medications that could interfere with responses to an experimental intervention. However, to date, clinical trial reporting for NAFLD has been suboptimal, limiting our understanding. Frequently dysmetabolic comorbidities and/or daily habits are not reported or adequately accounted for. Herein, we suggest new strategies to integrate the spectra of comorbidities usually present in patients with NAFLD, accounting for the impact of lifestyle, to develop personalised therapeutic approaches. First, the mechanism of action of the drug being explored should be considered. Second, the same proportion of patients with relevant metabolic comorbidities should be maintained from phase II to III clinical trials, if such comorbidities are expected to impact on the treatment response. Third, innovative trial designs, such as the adaptative, umbrella or basket strategies, could be used to increase the efficiency of clinical trials, potentially benefiting patients while reducing costs and enhancing the likelihood of finding a real benefit of the therapy being studied. Finally, alcohol intake and daily exercise should be assessed objectively not only in the screening period but also during follow-up.

Prevalence of NASH/NAFLD in people with obesity who are currently classified as metabolically healthy

BACKGROUND

While metabolic health in obesity may confer a protective status, recent studies indicate that nonalcoholic fatty liver disease (NAFLD) or even nonalcoholic steatohepatitis (NASH) may exist in this category of individuals. Although cardiovascular and diabetic risks have been well described, the risk of NAFLD and NASH among this population requires further investigation.

OBJECTIVE

Our goal was to compare the prevalence of steatosis, NAFLD, and NASH between individuals with metabolically healthy obesity (MHO) and individuals with metabolically abnormal obesity (MAO) and to identify preoperative risk factors for these conditions in a prospective cohort with morbid obesity scheduled for bariatric surgery.

SETTINGS

Tertiary referral university hospital in France.

METHODS

The prospective cohort included 837 bariatric patients who also had an intraoperative liver biopsy between 2002 and 2015. Obese individuals fulfilling none of the criteria in the strict definition of metabolic syndrome were considered metabolically healthy. Preoperative blood samples and liver pathology examinations were reviewed. Steatosis, NAFLD, and NASH were carefully identified allowing comparison of prevalence and risk factors between the 2 cohorts.

RESULTS

In total, 149 patients (17.8%) had MHO and the remaining 688 (82.2%) had MAO. The cohort with MHO was significantly younger, had a significantly lower glycosylated hemoglobin, a lower homeostasis model assessment of insulin resistance, and increased C-reactive protein. In individuals with MHO, 44 patients (29.5%) had at least moderate steatosis (>33% macrovesicular steatosis) and 5.4% had NASH. Using logistic regression, waist circumference was positively associated with NASH, whereas body mass index and alanine aminotransferase were significantly associated with severe steatosis (>66%).

CONCLUSION

Our study indicates that obese individuals without metabolic syndrome may develop subclinical liver involvement. Therefore, the occurrence of NAFLD and NASH in this population needs further investigation.

Epidemiology and pathophysiology of the association between NAFLD and metabolically healthy or metabolically unhealthy obesity

The prevalence of nonalcoholic fatty liver disease (NAFLD) is continuing to rise in many countries, paralleling the epidemic of obesity worldwide. In the last years, the concept of metabolically healthy obesity [MHO, generally defined as obesity without metabolic syndrome (MetS)] has raised considerable scientific interest. MHO is a complex phenotype with risks intermediate between metabolically healthy individuals with normal-weight (NWMH) and patients who are obese and metabolically unhealthy (MUO, i.e. obesity with MetS). In this review we aimed to examine the association and pathophysiological link of NAFLD with MHO and MUO. Compared to NWMH individuals, patients with obesity, regardless of the presence of MetS features, are at higher risk of all-cause mortality and cardiovascular events. Moreover, MHO patients have a greater risk of NAFLD development and progression compared to NWMH individuals. However, this risk is generally lower than that of MUO patients, suggesting a stronger adverse effect of coexisting MetS disorders than obesity per se on the severity of NAFLD. Nevertheless, since MHO is a dynamic state (with a significant proportion of MHO subjects progressing to MUO over time) and NAFLD itself may predict the transition from MHO to MUO, we believe that any effort should be made to identify NAFLD in all obese individuals, although they appear to be "metabolically healthy". Future research is needed to better understand the role of NAFLD and other pathogenic factors potentially involved in the transition from MHO to MUO and to elucidate how this transition may affect the presence and severity of NAFLD.

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.

Epidemiology of nonalcoholic fatty liver disease in non-obese populations: Meta-analytic assessment of its prevalence, genetic, metabolic, and histological profiles

OBJECTIVE

As a subgroup of nonalcoholic fatty liver disease (NAFLD), patients with non-obese NAFLD may also have an increased risk of adverse hepatic and metabolic outcomes. We aimed to estimate the prevalence and incidence of non-obese NAFLD and to describe its clinical characteristics in this systematic review and meta-analysis.

METHODS

We performed a systematic search of 1235 citations published up to Mar 2020. Meta-analyses, stratified analyses and meta-regression were all performed.

RESULTS

Of the 46 studies included, 28 cross-sectional and longitudinal studies of 155 846 non-obese participants reported a pooled NAFLD prevalence of 14.5% (95% confidence interval [CI] 12.3%-17.1%). A multivariate meta-regression analysis showed the trend that the prevalence varied by their geographical location. Further stratified analyses showed that NAFLD was relatively prevalent among people aged ≥45 years (16.2%; 95% CI 10.8-23.4) and those in South America (25.7%; 95% CI 24.4-27.0). The PNPLA3 rs738409 gene polymorphism was more frequently observed in non-obese NAFLD than in both obese NAFLD and non-obese controls, while the metabolic profiles of non-obese NAFLD were less severe than those of the obese NAFLD group. Patients with non-obese NAFLD had 4.81-fold and 5.43-fold higher risk of diabetes mellitus and metabolic syndrome, respectively, than the non-obese controls.

CONCLUSIONS

Non-obese NAFLD is common, particularly in South America and among people aged ≥45 years. Metabolic diseases and PNPLA3 rs738409 gene polymorphism are more frequent in the non-obese NAFLD group than in non-obese controls.

A new definition for metabolic dysfunction-associated fatty liver disease: An international expert consensus statement

The exclusion of other chronic liver diseases including "excess" alcohol intake has until now been necessary to establish a diagnosis of metabolic dysfunction-associated fatty liver disease (MAFLD). However, given our current understanding of the pathogenesis of MAFLD and its rising prevalence, "positive criteria" to diagnose the disease are required. In this work, a panel of international experts from 22 countries propose a new definition for the diagnosis of MAFLD that is both comprehensive and simple, and is independent of other liver diseases. The criteria are based on evidence of hepatic steatosis, in addition to one of the following three criteria, namely overweight/obesity, presence of type 2 diabetes mellitus, or evidence of metabolic dysregulation. We propose that disease assessment and stratification of severity should extend beyond a simple dichotomous classification to steatohepatitis vs. non-steatohepatitis. The group also suggests a set of criteria to define MAFLD-associated cirrhosis and proposes a conceptual framework to consider other causes of fatty liver disease. Finally, we bring clarity to the distinction between diagnostic criteria and inclusion criteria for research studies and clinical trials. Reaching consensus on the criteria for MAFLD will help unify the terminology (e.g. for ICD-coding), enhance the legitimacy of clinical practice and clinical trials, improve clinical care and move the clinical and scientific field of liver research forward.

Growing burden of nonalcoholic fatty liver disease in Turkey: A single-center experience

BACKGROUND/AIMS

Nonalcoholic fatty liver disease (NAFLD), which consists of nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH), is a growing epidemic in Turkey, considering the recent alarming prevalence of 48.3%. Patients with NASH and/or liver fibrosis are more likely to progress to advanced liver disease. In this single-center study, we sought to describe the clinical and histological characteristics of a sample of Turkish patients with biopsy-proven NAFLD, who were enrolled over a 4-year period.

MATERIALS AND METHODS

This is a retrospective analysis of prospectively collected data from a total of 468 patients (224 males, 244 females; median age, 47 [18-71]. The study cohort consisted of patients with biopsy-proven NAFLD who were followed up at our outpatient clinic from 2009 to 2010 and from 2017 to 2018. Histological classification of the biopsies was performed according to the Steatosis, Activity and Fibrosis (SAF) scoring allowing the use of Fatty Liver Inhibition of Progression (FLIP) algorithm and the NAFLD Activity Score (NAS) scoring system.

RESULTS

Based on the SAF scoring, most patients (90.4%) had biopsy-proven NASH, whereas the NAFL was much rarer (9.6%). The prevalence of significant fibrosis (≥F2), advanced fibrosis (≥F3), and cirrhosis (F=4) was 35.0%, 17.5%, and 3.8%, respectively. The percentage of lean, overweight, and obese patients with NAFLD was 6.4%, 32.6%, and 61%, respectively. Metabolic syndrome was prevalent in 63% of the patients and Type 2 diabetes mellitus in 33.5%.

CONCLUSION

The growing burden of NAFLD as a public health problem in Turkey is underscored by its marked histological severity in terms of NASH and fibrosis. Well-conducted clinical trials will be essential for slowing down the NASH progression.

Noninvasive Serum Fibrosis Markers are Associated with Coronary Artery Calcification in Patients with Nonalcoholic Fatty Liver Disease

Background/Aims

Advanced hepatic fibrosis is associated with cardiovascular disease (CVD) in patients with nonalcoholic fatty liver disease (NAFLD). We investigated the association between noninvasive serum fibrosis markers and the coronary artery calcium score (CACS) in subjects with NAFLD.

Methods

We analyzed 665 NAFLD subjects without chronic liver disease or heart disease between 2011 and 2015. The noninvasive fibrosis markers that were used to evaluate the severity of hepatic fibrosis included the NAFLD fibrosis score (NFS), fibrosis-4 (FIB-4) score, Forn's index, and the aspartate aminotransferase to platelet ratio index (APRI).

Results

The areas under the receiver operating characteristics curves for the NFS, FIB-4 score, Forn's index and APRI for predicting CACS >100 were 0.689, 0.683, 0.659, and 0.595, respectively. According to the multivariate analysis, older age, increased body mass index (BMI), and decreased estimated glomerular filtration rate (eGFR) were significant factors associated with CACS >100. The NFS, FIB-4 score and APRI were significantly associated with CACS >100 after adjusting for age and gender (p=0.006, p=0.012, and p=0.012, respectively) and after adjusting for age, gender, BMI and eGFR (p=0.013, p=0.022, and p=0.027, respectively). Scores integrating noninvasive fibrosis markers and other risk factors improved the predictive accuracy.

Conclusions

The NFS and FIB-4 score were associated with coronary atherosclerosis in subjects with NAFLD. Furthermore, scores integrating these noninvasive scores and risk factors for CVD showed good discriminatory power in predicting CACS >100. Therefore, noninvasive serum fibrosis markers may be useful tools for identifying NAFLD subjects at a high risk for CVD.

Prevalence and Risk Factors of Metabolic Associated Fatty Liver Disease in Xinxiang, China

Metabolic associated fatty liver disease (MAFLD) is recognized as the liver disease component of metabolic syndrome, which is mainly related to insulin resistance and genetic susceptibility. It is the most prevalent chronic liver disease worldwide. With rapid lifestyle transitions, its prevalence worldwide is increasing, and tremendous challenges in controlling this pandemic are arising. The objective of this study was to investigate the prevalence and risk factors of MAFLD in rural areas of Xinxiang, Henan in 2017. We conducted a cross-sectional analysis of rural inhabitants aged 20–79 years in Xinxiang, Henan in 2017, using cluster random sampling (N = 9140). Physical examinations were conducted at local clinics from April to June 2017. After overnight fasting, all participants underwent physical examinations, blood routine tests, biochemical examinations, and liver ultrasound and completed questionnaires. We investigated the crude and age-adjusted MAFLD prevalence and analyzed the characteristics of those with, and without, MAFLD, using logistic regression. Approximately 2868 (31.38%) participants were diagnosed with MAFLD. The overall age-adjusted MAFLD prevalence was 29.85% (men: 35.36%; women: 26.49%). The MAFLD prevalence increased with age, and peaked at the 50–59-year age group, and then began to decline. Higher body mass index, waist circumference, percentage of lymphocytes, levels of hemoglobin, platelet count, triglyceride, fasting plasma glucose, and serum uric acid were independently and positively correlated with MAFLD; In contrary, active physical activity and high-density lipoprotein cholesterol were negatively correlated with MAFLD. In summary, the MAFLD prevalence in the study population was 29.85%. Higher body mass index, waist circumference, percentage of lymphocytes, levels of hemoglobin, platelet count, triglyceride, fasting plasma glucose, and serum uric acid were risk factors for MAFLD.

The sensibility of the new blood lipid indicator--atherogenic index of plasma (AIP) in menopausal women with coronary artery disease

Background

Dyslipidemia is a key driver of coronary artery disease (CAD) development. This study aimed to determine whether the atherogenic index of plasma (AIP), a novel comprehensive lipid index, is an independent and reliable predictor of CAD risk in postmenopausal women.

Methods

A cohort of consecutive 4644 postmenopausal women (aged 50 or above) undergoing coronary angiography (CAG) in Anzhen Hospital (Beijing, China) from January–December 2014 was included in the analysis. Of them, 3039 women were CAD patients, and 1605 were non-CAD subjects.

Results

Relative to control subjects, TG levels in CAD patients were higher and HDL-C levels were lower. In CAD patients, non-traditional lipid profile values (TC/HDL-C, AI, and AIP) were significantly elevated relative to controls. AIP was positively correlated with TC (r = 0.157), TG (r = 0.835), LDL-C (r = 0.058), non-HDL-C (r = 0.337), TC/HDL-C (r = 0.683), LDL-C/HDL-C (r = 0.437), LCI (r = 0.662), and AI (r = 0.684), and negatively correlated with HDL-C (r = − 0.682) (all P < 0.001), but was independent of age (r = − 0.022; P = 0.130) and BMI (r = 0.020, P = 0.168). Aunivariate logistic regression analysis revealed AIP to be the measured lipid parameter most closely related to CAD, and its unadjusted odds ratio was 1.824 (95% CI: 1.467–2.267, P < 0.001). After adjusting for several CAD risk factors (age, BMI, smoking, drinking, EH, DM, hyperlipidemia, and family history of CVD, AIP was still found to represent a significant CAD risk factor (OR 1.553, 95% CI: 1.234–1.955, P < 0. 001).

Conclusion

AIP may be a powerful independent predictor of CAD risk in Chinese Han postmenopausal women, and may be superior to the traditional lipid indices.

Natural history of NASH and HCC

Widespread unhealthy dietary habits associated with a sedentary lifestyle have made NAFLD the most frequent chronic liver disease worldwide, with a global prevalence of ~25%. Although NAFLD is mainly considered to be a benign disease, it can progress to severe liver fibrosis and hepatocellular carcinoma (HCC), with the latter found in non-cirrhotic livers in about 40% of cases. Factors favouring the progression of liver disease in NAFLD are only partially understood. Male sex, older age and Caucasian ethnicity have frequently been identified as factors accelerating the progression of fibrosis in NAFLD, although data are not consistent. Host genetic variants appear to be very important, especially in the gene coding for the patatin-like phospholipase domain-containing 3 (PNPLA3), and they may also play a role in the development of HCC, independent of activity and the extent of liver damage. However, the most important factors affecting disease progression are found in the metabolic syndrome, that is, obesity, type 2 diabetes and arterial hypertension. This mini-review will discuss the contribution of these factors to NAFLD-associated morbidity, emphasizing the importance of preventive measures such as physical activity and weight control in view of the current pandemic of the metabolic syndrome.

Development and Validation of Hepamet Fibrosis Scoring System-A Simple, Noninvasive Test to Identify Patients With Nonalcoholic Fatty Liver Disease With Advanced Fibrosis

BACKGROUND & AIMS

Fibrosis affects prognoses for patients with nonalcoholic fatty liver disease (NAFLD). Several non-invasive scoring systems have aimed to identify patients at risk for advanced fibrosis, but inconclusive results and variations in features of patients (diabetes, obesity and older age) reduce their diagnostic accuracy. We sought to develop a scoring system based on serum markers to identify patients with NAFLD at risk for advanced fibrosis.

METHODS

We collected data from 2452 patients with NAFLD at medical centers in Italy, France, Cuba, and China. We developed the Hepamet fibrosis scoring system using demographic, anthropometric, and laboratory test data, collected at time of liver biopsy, from a training cohort of patients from Spain (n = 768) and validated the system using patients from Cuba (n = 344), Italy (n = 288), France (n = 830), and China (n = 232). Hepamet fibrosis score (HFS) were compared with those of previously developed fibrosis scoring systems (the NAFLD fibrosis score [NFS] and FIB-4). The diagnostic accuracy of the Hepamet fibrosis scoring system was assessed based on area under the receiver operating characteristic (AUROC) curve, sensitivity, specificity, diagnostic odds ratio, and positive and negative predictive values and likelihood ratios.

RESULTS

Variables used to determine HFS were patient sex, age, homeostatic model assessment score, presence of diabetes, levels of aspartate aminotransferase, and albumin, and platelet counts; these were independently associated with advanced fibrosis. HFS discriminated between patients with and without advanced fibrosis with an AUROC curve value of 0.85 whereas NFS or FIB-4 did so with AUROC values of 0.80 (P = .0001). In the validation set, cut-off HFS of 0.12 and 0.47 identified patients with and without advanced fibrosis with 97.2% specificity, 74% sensitivity, a 92% negative predictive value, a 76.3% positive predictive value, a 13.22 positive likelihood ratio, and a 0.31 negative likelihood ratio. HFS were not affected by patient age, body mass index, hypertransaminasemia, or diabetes. The Hepamet fibrosis scoring system had the greatest net benefit in identifying patients who should undergo liver biopsy analysis and led to significant improvements in reclassification, reducing the number of patients with undetermined results to 20% from 30% for the FIB-4 and NFS systems (P < .05).

CONCLUSIONS

Using clinical and laboratory data from patients with NAFLD, we developed and validated the Hepamet fibrosis scoring system, which identified patients with advanced fibrosis with greater accuracy than the FIB-4 and NFS systems. the Hepamet system provides a greater net benefit for the decision-making process to identify patients who should undergo liver biopsy analysis.

The Role of Thyroid Hormones and Autoantibodies in Metabolic Dysfunction Associated Fatty Liver Disease: TgAb May Be a Potential Protective Factor

BACKGROUND

Previous studies have shown that metabolic dysfunction associated fatty liver disease (MAFLD) is associated with thyroid hormones (THs), immunity, and inflammation status, but few studies involved thyroid autoimmunity. This study aimed to evaluate the role of THs, thyroid autoantibodies, inflammatory biomarkers in MAFLD, its cofactors, and other possible determinants.

MATERIALS AND METHODS

In the study, a total of 424 Chinese patients were selected and categorized as non-MAFLD and MAFLD. Serum thyroid hormone, thyroid autoantibody and high-sensitive C-reactive protein (hsCRP) levels were measured. The data of blood pressure, the serum lipid profile, glucose and liver enzymes were collected. The differences and association between research findings were examined and analyzed by Wilcoxon Signed Rank Test, One-Way ANOVA test and Multiple Logistic Regression models.

RESULTS

The study showed significant increase in the prevalence of MAFLD with high thyroid stimulating hormone (TSH) levels (P < 0.01) and abnormal high-sensitive C-reactive protein (hsCRP) levels (P < 0.01). The proportion of MAFLD patients decreased significantly with the rise of free thyroxine (FT4) (P = 0.04), thyrotropin receptor antibodies (TRAb) (P < 0.01), anti-thyroglobulin antibodies (TgAb) (P < 0.01), and thyroid peroxidase antibodies (TPOAb) levels (P < 0.01). Based on logistic regression analysis, MAFLD was significantly associated with lower levels of TgAb (P < 0.01), TPOAb (P < 0.01), and higher levels of hsCRP (P < 0.01) in male. In female, elevated TgAb (P < 0.01) may be a protective factor, while higher levels of hsCRP (P < 0.01) showed increased risk of MAFLD. Logistic models were adjusted for age, BMI, SBP, DBP, FBG, ALT, AST, TC, TG, LDL, HDL.

CONCLUSIONS

Taken together, TgAb may be a potential protective factor for MAFLD and elevated hsCRP level should be considered as an independent risk factor for MAFLD in both genders. TPOAb also demonstrated protective effect, but only in male. The prevalence of MAFLD increased with higher TSH levels and lower FT4, TRAb levels, but no significant association were found. However, Our findings provide a new insight into the pathogenesis of MAFLD by further investigating the impact of THs, thyroid autoimmunity, and inflammation on MAFLD patients.

Characterizing specific subgroups in patients with NAFLD: overweight vs obese phenotype

Non-alcoholic fatty liver disease (NAFLD) is increasingly recognized as the most common cause of chronic liver disease worldwide, with a global prevalence of 25.2%. The high burden of NAFLD extends beyond liver diseases, as patients are at risk of developing not only liver related conditions, including cirrhosis and hepatocellular carcinoma, but also cardiovascular complications associated to metabolic syndrome. The present special issue of The Spanish Journal of Gastroenterology (Revista Española de Enfermedades Digestivas) focusses on diverse key aspects of NAFLD, including characterization of fecal microbiota profiles, the role of bariatric endoscopy, evaluation of suitable pre-clinical models for NAFLD or differential epidemiological risk factors associated to NASH and fibrosis.

Collagen proportionate area is an independent predictor of long-term outcome in patients with non-alcoholic fatty liver disease

BACKGROUND

Collagen proportionate area (CPA) measurement is a technique that quantifies fibrous tissue in liver biopsies by measuring the amount of collagen deposition as a proportion of the total biopsy area. CPA predicts clinical outcomes in patients with HCV and can sub-classify cirrhosis.

AIM

To test the ability of CPA to quantify fibrosis and predict clinical outcomes in patients with NAFLD.

METHODS

We assessed consecutive patients with biopsy-proven NAFLD from three European centres. Clinical and laboratory data were collected at baseline and at the time of the last clinical follow-up or death. CPA was performed at two different objective magnifications, whole biopsy macro and ×4 objective magnification, named standard (SM) and high (HM) magnification respectively. The correlation between CPA and liver stiffness was assessed in a sub-group of patients.

RESULTS

Of 437 patients, 32 (7.3%) decompensated and/or died from liver-related causes during a median follow-up of 103 months. CPA correlated with liver stiffness and liver fibrosis stage across the whole spectrum of fibrosis. HM CPA was significantly higher than SM CPA in stages F0-F3 but similar in cirrhosis, reflecting a higher ability to capture pericellular/perisinusoidal fibrosis at early stages. Age at baseline (HR: 1.04, 95% CI: 1.01-1.08), HM CPA (HR: 1.04 per 1% increase, 95% CI: 1.01-1.08) and presence of advanced fibrosis (HR: 15.4, 95% CI: 5.02-47.84) were independent predictors of liver-related clinical outcomes at standard and competing risk multivariate Cox-regression analysis.

CONCLUSIONS

CPA accurately measures fibrosis and is an independent predictor of clinical outcomes in NAFLD; hence it merits further evaluation as a surrogate endpoint in clinical trials.

Derivation and validation of a cardiovascular risk score for prediction of major acute cardiovascular events in non-alcoholic fatty liver disease; the importance of an elevated mean platelet volume

BACKGROUND

Atherosclerotic cardiovascular disease is a key cause of morbidity in non-alcoholic fatty liver disease (NAFLD) but appropriate means to predict major acute cardiovascular events (MACE) are lacking.

AIM

To design a bespoke cardiovascular risk score in NAFLD.

METHODS

A retrospective derivation (2008-2016, 356 patients) and a prospective validation (2016- 2017, 111 patients) NAFLD cohort study was performed. Clinical and biochemical data were recorded at enrolment and mean platelet volume (MPV), Qrisk2 and Framingham scores were recorded one year prior to MACE (Cardiovascular death, acute coronary syndrome, stroke and transient ischaemic attack).

RESULTS

The derivation and validation cohorts were well-matched, with MACE prevalence 12.6% and 12%, respectively. On univariate analysis, age, diabetes, advanced fibrosis, collagen proportionate area >5%, MPV and liver stiffness were associated with MACE. After multivariate analysis, age, diabetes and MPV remained independently predictive of MACE. The "NAFLD CV-risk score" was generated using binary logistic regression: 0.06*(Age) + 0.963*(MPV) + 0.26*(DM¹ ) - 16.44; ¹ Diabetes mellitus: 1: present; 2: absent. (AUROC 0.84). A cut-off of -3.98 gave a sensitivity 97%, specificity 27%, PPV 16%, and NPV 99%. An MPV alone of >10.05 gave a sensitivity 97%, specificity 59%, PPV 24% and NPV 97% (AUROC 0.83). Validation cohort AUROCs were comparable at 0.77 (NAFLD CV-risk) and 0.72 (MPV). In the full cohort, the NAFLD CV-risk score and MPV outperformed both Qrisk2 and Framingham scores.

CONCLUSIONS

The NAFLD CV risk score and MPV accurately predict 1-year risk of MACE, thereby allowing better identification of patients that require optimisation of their cardiovascular risk profile.

Impact of a structured lifestyle programme on patients with metabolic syndrome complicated by non-alcoholic fatty liver disease

BACKGROUND

Lifestyle interventions are first-line therapy for non-alcoholic fatty liver disease (NAFLD).

AIMS

To examine the prevalence of NAFLD among participants of the University of Michigan Metabolic Fitness (MetFit) Programme and to assess the impact of this programme on weight, metabolic and liver-related parameters among patients with and without NAFLD.

METHODS

Adults who completed the programme between 2008 and 2016 were included. Clinical and laboratory data were collected at enrolment, and at 12 and 24 weeks. NAFLD was defined based on liver biopsy, imaging or clinical diagnosis.

RESULTS

The cohort (N = 403; 253 12-week, 150 24-week) consisted primarily of middle-aged (median 54 years) white (88%) men (63%) with severe obesity (median BMI 37.4). 47.6% met criteria for NAFLD. At baseline, NAFLD patients were younger (52 vs 55 years), had higher weights and more metabolic derangements (higher fasting insulin and triglyceride, lower high-density lipoprotein-cholesterol). At programme completion, 30% achieved weight reduction ≥5%, 62% resolution of hypertriglyceridaemia, 33% resolution of low HDL, 27% resolution of impaired fasting glucose and 43% normalisation of alanine aminotransferase. Endpoints were unaffected by NAFLD. Longer programme duration (OR 6.7, 95% CI 3.6-12.3) and white race (OR 3.83, 95% CI 1.04-1.76) were independent predictors of ≥5% weight loss.

CONCLUSIONS

Nearly half of the patients referred to a structured lifestyle programme for metabolic syndrome had NAFLD. Although baseline metabolic derangements were more pronounced among NAFLD patients, the programme was equally efficacious in achieving weight loss and resolving metabolic syndrome components. Programme duration was the most important predictor of response.