Fatty liver index as a predictive marker for the development of diabetes: A retrospective cohort study using Japanese health check-up data

Metabolic dysfunction-associated steatotic liver disease, metabolic alcohol-related liver disease, and incident dementia: a nationwide cohort study : MASLD, MetALD, and dementia risk

BACKGROUND

The relationship between the newly proposed steatotic liver disease (SLD) subtypes-metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic alcohol-associated liver disease (MetALD)-and dementia is understudied. We evaluated the dementia risk associated with these subtypes.

METHODS

This retrospective cohort study included 296,001 participants aged over 60 who underwent health examinations between 2009 and 2010. Participants were categorized into non-SLD (reference), MASLD, and MetALD groups and followed up until dementia onset, death, or December 31, 2019. SLD was defined by a fatty liver index ≥ 30, with (i) MASLD based on cardiometabolic risk factors, and (ii) MetALD as MASLD with moderate alcohol intake. Outcomes included overall dementia, Alzheimer's disease (AD), and vascular dementia (VaD). Subdistribution hazard ratios (SHRs) was calculated using the Fine-Gray model, treating death as a competing risk.

RESULTS

Over 7,430,253 person-years of follow-up, 11,345 dementia cases occurred (10,863 AD and 2,159 VaD). Adjusted SHRs for MASLD were 1.10 (1.07-1.13) for AD and 1.20 (1.13-1.27) for VaD. For MetALD, SHRs were 0.90 (0.87-0.94) for AD and 1.53 (1.40-1.66) for VaD. Dementia risk in both MASLD and MetALD increased over longer periods, with MetALD initially linked to increased VaD risk and decreased AD risk, which reversed after three years.

CONCLUSIONS

MASLD and MetALD were associated with increased risks of AD and VaD; MetALD showing a stronger association with VaD. Understanding the distinct effects of different SLD subtypes on dementia is crucial for improving risk assessment and management strategies.

Pre-diabetes and cardiovascular risk factors in NAFLD patients: a retrospective comparative analysis

Objectives

Insulin resistance plays a critical role in the pathophysiology of diabetes mellitus and non-alcoholic fatty liver disease (NAFLD). Moreover, insulin resistance has a central role in atherogensis as the major leading cause of cardiovascular disease (CVD). The aim of the present study was to assess the frequency of pre-diabetes and evaluate the cardiometabolic risk factors among NAFLD patients, comparing those with pre-diabetes to those with normal glucose tolerance.

Methods

In the current retrospective case-control study, the data of 1031 NAFLD patients was retrieved. Based on blood glucose levels, 337 diabetics, 340 pre-diabetes, and, 354 normal glucose patients were diagnosed. After excluding diabetic NAFLD patients, 694 individuals were divided into two groups: normal glucose and pre-diabetes. Various variables, such as age, anthropometric measurements, hypertension, systolic and diastolic blood pressure, and lipid profiles, were extracted from patient files. Statistical analysis was conducted to assess cardiovascular risk factors in NAFLD patients.

Results

Higher age, female gender, higher BMI, triglyceride, waist and hip circumference and waist-to-hip ratio were found in pre-diabetic NAFLD individuals compared with normoglycemic ones (P-value<0.05). Multivariable age-, sex-, BMI- and smoking- adjusted logistic regression showed a predicting role of pre-diabetes and NAFLD concurrence with metabolic syndrome (P-value<0.001, OR:4.31, 95% CI: 2.95- 6.29), but not CVD (P-value=0.353, OR:1.37, 95% CI: 0.71- 2.61).

Conclusion

In this study, nearly one-third of NAFLD patients had pre-diabetes. The mean value of age, BMI, TG, waist and Hip circumference was significantly higher in pre-diabetic patients. The concurrence of pre-diabetes and NAFLD was a predicting factor for metabolic syndrome, but not CVD events.

Fatty Liver Index and the Risk of Atrial Fibrillation in a General Japanese Population - The Suita Study

BACKGROUND

Atrial fibrillation (AF) is the most diagnosed arrhythmia in clinical settings. The fatty liver index (FLI) is a marker of liver steatosis with potential cardiovascular implications. This study investigated whether FLI could predict the risk of AF.

METHODS AND RESULTS

We used data from the Suita Study, a Japanese population-based prospective cohort study. A total of 2,346 men and 3,543 women, aged 30-84 years, without prevalent AF were included and followed up. The diagnosis of AF was established during follow-up using electrocardiograms, hospital records, and death certificates. FLI was assessed during a baseline health checkup. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for incident AF per FLI quintile and log-transformed FLI. Within a median 14.5 years of follow-up, 142 men and 105 women developed AF. Compared with women in the third (middle) FLI quintile, women in the first (lowest), fourth, and fifth (highest) quintiles showed a higher risk of AF, with multivariable-adjusted HRs of 2.37 (95% CI 1.06-5.31), 2.60 (95% CI 1.30-5.17), and 2.04 (95% CI 1.00-4.18), respectively. No corresponding associations were observed in men. The change in log-transformed FLI was not associated with the risk of AF in either sex.

CONCLUSIONS

A U-shaped association between FLI and AF risk was detected in Japanese women. FLI could be a screening tool to detect women at high risk of developing AF.

The Role of the Fatty Liver Index (FLI) in the Management of Non-Alcoholic Fatty Liver Disease: A Systematic Review

Currently, non-alcoholic fatty liver disease is the most common liver disease worldwide, with a prevalence of 32%. It is much more common among men (40%) and among patients with metabolic comorbidities such as obesity, diabetes and dyslipidemia. Being an asymptomatic disease, the diagnosis is often established on the basis of imaging methods, with an important role given to abdominal ultrasonography, computed tomography and magnetic resonance imaging. In order to facilitate diagnosis, experts have introduced a series of blood biomarkers. Two biomarker panels are currently validated for the diagnosis of non-alcoholic fatty liver disease: the fatty liver index, and the hepatic steatosis index. The fatty liver index has been in use in medical practice for over 17 years and has demonstrated its accuracy in various studies that compared it with other diagnostic methods, highlighted its role in screening patients with cardiovascular risk and validated the effects of different diets and drugs that are proposed for the treatment of the disease. In the management of non-alcoholic fatty liver disease, the fatty liver index is an important algorithm in the diagnosis and prognosis of patients with metabolic risk. Taking into account the diversity of drugs to be approved in the treatment of non-alcoholic fatty liver disease, the fatty liver index will become an effective tool in monitoring the effects of these therapies.

The Link between NAFLD and Metabolic Syndrome

Metabolic syndrome (MetS) is characterized by an association of cardiovascular and diabetes mellitus type 2 risk factors. Although the definition of MetS slightly differs depending on the society that described it, its central diagnostic criteria include impaired fasting glucose, low HDL-cholesterol, elevated triglycerides levels and high blood pressure. Insulin resistance (IR) is believed to be the main cause of MetS and is connected to the level of visceral or intra-abdominal adipose tissue, which could be assessed either by calculating body mass index or by measuring waist circumference. Most recent studies revealed that IR may also be present in non-obese patients, and considered visceral adiposity to be the main effector of MetS' pathology. Visceral adiposity is strongly linked with hepatic fatty infiltration also known as non-alcoholic fatty liver disease (NAFLD), therefore, the level of fatty acids in the hepatic parenchyma is indirectly linked with MetS, being both a cause and a consequence of this syndrome. Taking into consideration the present pandemic of obesity and its tendency to drift towards a progressively earlier onset due to the Western lifestyle, it leads to an increased NAFLD incidence. Novel therapeutic resources are lifestyle intervention with physical activity, Mediterranean diet, or therapeutic surgical respective metabolic and bariatric surgery or drugs such as SGLT-2i, GLP-1 Ra or vitamin E. NAFLD early diagnosis is important due to its easily available diagnostic tools such as non-invasive tools: clinical and laboratory variables (serum biomarkers): AST to platelet ratio index, fibrosis-4, NAFLD Fibrosis Score, BARD Score, fibro test, enhanced liver fibrosis; imaging-based biomarkers: Controlled attenuation parameter, magnetic resonance imaging proton-density fat fraction, transient elastography (TE) or vibration controlled TE, acoustic radiation force impulse imaging, shear wave elastography, magnetic resonance elastography; and the possibility to prevent its complications, respectively, fibrosis, hepato-cellular carcinoma or liver cirrhosis which can develop into end-stage liver disease.

Nonalcoholic fatty liver disease and diabetes

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease in the world and represents a clinical-histopathologic entity where the steatosis component may vary in degree and may or may not have fibrotic progression. The key concept of NAFLD pathogenesis is excessive triglyceride hepatic accumulation because of an imbalance between free fatty acid influx and efflux. Strong epidemiological, biochemical, and therapeutic evidence supports the premise that the primary pathophysiological derangement in most patients with NAFLD is insulin resistance; thus the association between diabetes and NAFLD is widely recognized in the literature. Since NAFLD is the hepatic manifestation of a metabolic disease, it is also associated with a higher cardio-vascular risk. Conventional B-mode ultrasound is widely adopted as a first-line imaging modality for hepatic steatosis, although magnetic resonance imaging represents the gold standard noninvasive modality for quantifying the amount of fat in these patients. Treatment of NAFLD patients depends on the disease severity, ranging from a more benign condition of nonalcoholic fatty liver to nonalcoholic steatohepatitis. Abstinence from alcohol, a Mediterranean diet, and modification of risk factors are recommended for patients suffering from NAFLD to avoid major cardiovascular events, as per all diabetic patients. In addition, weight loss induced by bariatric surgery seems to also be effective in improving liver features, together with the benefits for diabetes control or resolution, dyslipidemia, and hypertension. Finally, liver transplantation represents the ultimate treatment for severe nonalcoholic fatty liver disease and is growing rapidly as a main indication in Western countries. This review offers a comprehensive multidisciplinary approach to NAFLD, highlighting its connection with diabetes.

Identification of novel targets in adipose tissue involved in non-alcoholic fatty liver disease progression

Obesity is a major risk factor for the development of Nonalcoholic fatty liver disease (NAFLD). We hypothesize that a dysfunctional subcutaneous white adipose tissue (scWAT) may lead to an accumulation of ectopic fat in the liver. Our aim was to investigate the molecular mechanisms involved in the causative role of scWAT in NALFD progression. We performed a RNA-sequencing analysis in a discovery cohort (n = 45) to identify genes in scWAT correlated with fatty liver index, a qualitative marker of liver steatosis. We then validated those targets in a second cohort (n = 47) of obese patients who had liver biopsies available. Finally, we obtained scWAT mesenchymal stem cells (MSCs) from 13 obese patients at different stages of NAFLD and established in vitro models of human MSC (hMSC)-derived adipocytes. We observed impaired adipogenesis in hMSC-derived adipocytes as liver steatosis increased, suggesting that an impaired adipogenic capacity is a critical event in the development of NAFLD. Four genes showed a differential expression pattern in both scWAT and hMSC-derived adipocytes, where their expression paralleled steatosis degree: SOCS3, DUSP1, SIK1, and GADD45B. We propose these genes as key players in NAFLD progression. They could eventually constitute potential new targets for future therapies against liver steatosis.

Hepatic Steatosis and High-normal Fasting Glucose as Risk Factors for Incident Prediabetes

Context

The role of hepatic steatosis (HS) in the initial stages of developing type 2 diabetes remains unclear.

Objective

We aimed to clarify the impact of HS indexed by Fatty Liver Index (FLI) and high-normal fasting plasma glucose (FPG) as risk factors for incident prediabetes in a nonobese cohort.

Methods

Data from 1125 participants with ADA-defined normal glucose metabolism (median age 52 years; BMI 23.1 kg/m²) were used for retrospective analysis. In the entire population, correlation between normal FPG and FLI was evaluated by multiple regression adjusted for age and sex. Follow-up data from 599 participants in whom 75-g OGTT was repeated 3.7 years later showed that 169 developed prediabetes. This was analyzed by the multivariate Cox proportional hazards model.

Results

In the entire population, FLI was positively correlated with FPG (P < 0.01): mean FLI increased from 15.8 at FPG 4.2 mmol/L to 31.6 at FPG 5.5 mmol/L. Analysis of the 599 participants (2061 person-years) by Cox model, adjusted for sex, age, family history of diabetes, ISI_MATSUDA, and Stumvoll-1, clarified an increased risk of prediabetes with high-normal FPG and FLI. Risk was increased 2.2 times with FLI ≥ 16.5 vs FLI < 16.5, P < 0.001, and increased 2.1 times in participants with FPG ≥ 5.3 mmol/L, P < 0.001. Cutoff values (unadjusted) were obtained by ROC at the point of the largest Youden’s index using the entire range of the variables.

Conclusion

Even among nonobese individuals, HS indexed by FLI and a high-normal FPG (≥ 5.3 mmol/L) are risk factors for prediabetes, independently from insulin.