Association of non-alcoholic fatty liver disease with microvascular complications of type 2 diabetes

Retinopathy in Metabolic Dysfunction-Associated Steatotic Liver Disease

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a multisystemic disease, i.e., influencing various organ systems beyond the liver and, thus, contributing to comorbidities. Characterized by excessive fat accumulation in the hepatocytes, MASLD is frequently linked to metabolic syndrome components, such as obesity, insulin resistance, dyslipidemia, and hypertension. Therefore, exploring the intricate connection between MASLD and other organ systems, including the eyes, seems to be essential. In this context, retinopathy has been investigated for its potential association with MASLD, since both conditions share common pathogenetic pathways. Chronic low-grade inflammation, oxidative stress, insulin resistance, and endothelial dysfunction are only some of those mechanisms contributing to disease progression and, possibly, determining the bidirectional interplay between the liver and retinal pathology. This narrative review aims to summarize data concerning the multisystemicity of MASLD, primarily focusing on its potential association with the eyes and, particularly, retinopathy. Identifying this possible association may emphasize the need for early screening and integrated management approaches that address the liver and eyes as interconnected components within the framework of a systemic disease. Further research is necessary to delineate the precise mechanisms and develop targeted interventions to mitigate the bidirectional impact between the liver and eyes, aiming to reduce the overall burden of disease and improve patient outcomes.

Metabolic syndrome traits differentially and cumulatively influence micro- and macrovascular disease risk in patients with MASLD

INTRODUCTION

The cumulative impact of metabolic syndrome (MetS) components on micro- and macrovascular disease in metabolic dysfunction-associated steatotic liver disease (MASLD) is unclear. We aimed to determine whether the number of the MetS components increases the risk of micro- and macrovascular disease in patients with MASLD.

METHODS

We performed a retrospective cohort study of electronic medical records using the TriNetX network, a global federated database. The exposure arm was patients with hepatic steatosis (defined via International Classification of Diseases, 10th Revision coding, or modified hepatic steatosis index), and ≥1 MetS components (obesity/central adiposity, insulin resistance, hypertension, or dyslipidaemia), compared with a reference arm of adults without any MetS components or hepatic steatosis. Our propensity score matched (1:1) for confounders with 5 years of follow-up. Primary outcomes included microvascular (peripheral neuropathy, retinopathy, and nephropathy) and macrovascular (cardiovascular events, cerebrovascular accidents, and peripheral vascular disease) disease. Secondary analyses assessed the impact of additional MetS components on these outcomes, as well as the impact of sex.

RESULTS

MASLD, defined by hepatic steatosis and insulin resistance (n = 15 937), carried the highest risk of microvascular disease (HR 13.93 (95% CI 8.55-22.68)), whilst MASLD, defined by hepatic steatosis and hypertension (n = 53 028), carried the highest risk of macrovascular disease (7.23 (6.45-8.13)). MASLD with all MetS components carried greatest risk of both micro- (31.20 (28.88-33.70) (n = 462 789)) and macrovascular (8.04 (7.33-8.82) (n = 336 010)) disease.

CONCLUSION

We demonstrate a differential effect of MetS components on micro- and macrovascular disease risk in patients with MASLD, with a cumulative impact of multiple MetS on overall risk. The impact of MetS components was most pronounced in women. Aggressive metabolic risk factor management is critical for prevention of micro- and macrovascular complications.

Noninvasive Liver Fibrosis Indices as Indicators of Microvascular and Macrovascular Complications in Type 2 Diabetes

Objective: Nonalcoholic fatty liver disease (NAFLD) is more prevalent in patients with obesity, diabetes, and metabolic syndrome, which are risk factors for nonalcoholic steatohepatitis and liver fibrosis. NAFLD is related to cardiovascular outcomes in diabetes. We aimed to investigate the relationship between diabetic complications and NAFLD fibrosis score (NFS) and Fibrosis-4 score (FIB-4). Methods: Three hundred patients with type 2 diabetes mellitus (T2DM) were retrospectively evaluated according to NAFLD diagnosis on ultrasound in outpatient clinic. Risk of advanced fibrosis was estimated using FIB-4 and NFS. Diabetic complications of the patients were noted. Results: Presence of diabetic retinopathy is related to FIB-4 (P = 0.001) and NFS (P < 0.001) scores. NFS score (P = 0.037), not FIB-4 (P = 0.517), is related to diabetic nephropathy. Among macrovascular complications, only coronary artery disease is related to NFS and FIB-4 scores (P = 0.037 and P = 0.004, respectively). Although we cannot establish any association between fasting blood glucose, glycosylated hemoglobin (HbA1c) values and noninvasive liver fibrosis scores (P > 0.05), diabetes duration, and age positively correlated with the FIB-4 score (P = 0.033, P = 0.001). In logistic regression analysis, NFS > 0.676 values are associated with increased rates of diabetic retinopathy, independent of age, sex, HbA1c, and duration diabetes (odds ratio: 1.155, P = 0.030). FIB-4 has no relation with microvascular complications according to logistic regression analysis (P > 0.05 for all). Neither FIB-4 nor NFS has an effect on the presence of macrovascular complications (P > 0.05 for all). Conclusion: Our findings suggest that increase in NFS score is associated with the presence of diabetic retinopathy, independent of confounding factors. Further studies are needed on the applicability of noninvasive fibrosis scores in monitoring the presence of diabetic microvascular and macrovascular complications.

Evidence for the Hepato-Retinal Axis: A Systematic Review

BACKGROUND AND OBJECTIVE

Liver health has been reported to be associated with retinal pathology in various ways. These include deposition of retino-toxins, neovascular drive, and disruption of the blood-retina barrier. Extrahepatic synthesis of implicated molecules and hemodynamic changes in liver dysfunction are also considered. The objective was to review the current evidence for and against a hepato-retinal axis that may guide further areas of preclinical and clinical investigation.

METHODS

This was a systematic review. PubMed and Cochrane were queried for English language studies examining the connection between hepatic dysfunction and retinal pathology.

RESULTS

Fourteen studies were included and examined out of 604 candidate publications. The studies selected include preclinical studies as well as clinical case series and studies.

CONCLUSIONS

Several liver pathologies may be linked to retinal pathology as mediated by hepatically synthesized molecules. The hepato-retinal axis may be present and further, targeted studies of the axis are warranted. [Ophthalmic Surg Lasers Imaging Retina 2024;55:587-596.].

Clinical Evidence of the Relationship Between Alanine Aminotransferase and Diabetic Kidney Disease

Aim

Multiple studies have investigated the association between alanine aminotransferase (ALT) and diabetes mellitus (DM); however, only a few studies have specifically examined the relationship between ALT and diabetic kidney disease (DKD). This study aimed to investigate the relationship between ALT and DKD using clinical data.

Methods

A cross-sectional study was conducted on 668 individuals that included non-DM (N=281), DM without DKD (N=160), and DKD (N=227) patients. A generalized additive model (GAM) was used to examine the dose-response relationship between ALT and DKD risk. We also analyzed the data from the US National Health and Nutrition Examination Survey (NHANES) 2015-2018 using the same statistical methods; 4481, 1110, and 671 individuals were included in the non-DM, DM without DKD, and DKD groups, respectively.

Results

The changes in ALT activity among the non-DM, DM without DKD, and DKD groups showed a similar pattern in both our clinical data and the NHANES dataset. ALT activity increases with the onset of DM, whereas ALT activity decreases when DM progresses to DKD. The GAM revealed a nonlinear U-shaped relationship between ALT and DKD risk in the two datasets, and the lowest range of ALT was 40-50 IU/L. Both lower (<40 IU/L) and higher (>50 IU/L) ALT activity were found to be positively associated with DKD risk.

Conclusion

A U-shaped nonlinear association between ALT and DKD was found in our clinical data and NHANES data. DKD risk was increased by both lower or higher ALT activity. To confirm the causality of nonlinear relationship, larger prospective studies or Mendelian randomization analysis are required.

Causal associations between liver enzymes and diabetic microvascular complications: A univariable and multivariable Mendelian randomization

BACKGROUND

Observational studies show that liver enzymes are diabetes risk factors. However, previous observational investigations on the relationship between liver enzymes and diabetic microvascular complications produced contradictory results. The purpose of this research is to examine the independent causal effects of liver enzymes on diabetic microvascular complications.

METHODS

Univariable Mendelian randomization (UVMR) and multivariable Mendelian randomization (MVMR) were utilized to disentangle the causal effects. The genome-wide association study (GWAS) summary-level statistics were collected from the UK biobank and the FinnGen consortium. Single nucleotide polymorphisms (SNPs) were selected as genetic instruments with genome-wide significance (p < 5 ×10-8). Five UVMR approaches, including inverse variance weighted (IVW), Bayesian weighted Mendelian randomization, MR-Pleiotropy Residual Sum and Outlier (MR-PRESSO), weighted median, and MR-Egger, and three MVMR approaches, including the extended versions of IVW, MR-Egger, and the Q-minimization methods, were performed to evaluate the causal effects. The robustness of the MR results was further confirmed using several sensitivity analyses.

RESULTS

UVMR revealed that a genetically predisposed per standard deviation increase in serum alanine aminotransferase (ALT) level increased the risk of diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM) (IVW OR = 1.489, 95% CI = 1.206-1.772, p = 0.006). Likewise, serum aspartate aminotransferase (AST) levels showed similar results (IVW OR = 1.376, 95% CI = 1.115-1.638, p = 0.017). Furthermore, these effects were consistent after controlling for glycemia and blood pressure using MVMR analysis. Additionally, sensitivity analyses further strengthened the causality. However, no significant associations were found between alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), and diabetic microvascular complications.

CONCLUSIONS

Robust evidence was demonstrated for an independent causal effect of serum ALT or AST concentration on the risk of DR in T2DM. Further investigations are necessary to elucidate the potential biological mechanisms and confirm their clinical significance for early prevention and intervention.

Association of HbA1c Variability with Vibrating Perception Threshold in Middle-Aged and Elderly Patients with Type 2 Diabetes Mellitus: A Retrospective Cohort Study

Purpose

To investigate the relationship between HbA1c variability and vibrating perception threshold (VPT) in middle-aged and elderly patients with type 2 diabetes mellitus (T2DM).

Patients and Methods

A total of 367 middle-aged and elderly patients with T2DM were enrolled. All patients were categorized into the control and vibration sensation deficiency group (VSD) based on VPT. Clinical data were collected. The coefficient of variation of glycated hemoglobin A1c (HbA1c-CV) and the mean glycated hemoglobin A1c(HbA1c-Mean) are considered as indexes of HbA1c variability. Multivariate logistic regression analysis, the generalized linear model and ROC curve correlation analysis were used to analyze the correlation of various factors and VPT.

Results

The multivariate logistic regression analysis revealed that age, systolic blood pressure (SBP), and HbA1c-CV were identified as risk factors for vibration sensation deficiency in middle-aged and elderly patients with T2DM, while estimated glomerular filtration rate (eGFR), triiodothyronine (T3), and alanine aminotransferase (ALT) were considered as protective factors. In the unadjusted generalized linear model, a significant association was observed between HbA1c-CV and VPT values. After adjusting for age, diabetic duration, SBP, homeostatic model assessment for beta-cell function (HOMA-β), ALT, eGFR, T3, 24-hour urinary protein excretion levels, and HbA1c-Mean, HbA1c-CV remained significantly correlated with VPT values on both sides. (left side, B=2.560, 95% CI 1.298~3.823; P<0.001; right side, B=2.608, 95% CI 1.498~3.718, P<0.001). The area under the curve (AUC) for HbA1c-CV and VSD prevalence was 0.723, with a sensitivity of 79.85%, specificity of 56.22%.

Conclusion

The risk of developing VSD increases proportionally with higher HbA1c-CV levels in middle-aged and elderly patients with T2DM. Reaching and maintaining blood glucose stability is essential to the mitigation of diabetes peripheral neuropathy occurrence.

Retinal Vascular Lesions in Patients with Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

Background: This systematic review and meta-analysis aimed to summarize and compare data on retinal vascular lesions between patients with nonalcoholic fatty liver disease (NAFLD) and individuals without the disease. Methods: Search was performed in PubMed, Scopus and Cochrane Library, complemented by handsearching (PROSPERO ID: CRD42022345558). Thirty-six studies comprising 24,985 individuals (12,387 NAFLD patients and 12,598 controls) were selected for the meta-analysis. Results: Apart from retinopathy, no study with a different type of retinal vascular lesion was retrieved. Overall, there was no significant difference in the presence of retinopathy in NAFLD patients compared to controls (Odds Ratio (OR) = 1.20; 95% Confidence Interval (CI): 0.91-1.59). Heterogeneity among studies was high (I² = 93%; p < 0.00001), while Egger's test revealed no publication bias (p = 0.60). However, subgroup analysis showed positive association between retinopathy and NAFLD in type 1 diabetes mellitus (T1DM) (OR = 2.35; 95% CI: 1.53-3.60), but not in type 2 diabetes mellitus patients. Meta-regression analysis exploring potential confounders revealed no significant association. Conclusions: The presence of retinopathy was not overall different between individuals with and without NAFLD; however, T1DM patients with NAFLD had higher rates of retinopathy compared to T1DM patients without NAFLD, a finding warranting further research to show whether NAFLD may predict retinopathy in T1DM patients.

Non-alcoholic fatty liver disease and incidence of microvascular complications of diabetes in patients with type 2 diabetes: a prospective cohort study

Objective

To investigate the association between non-alcoholic fatty liver disease (NAFLD) and liver enzymes with the incidence of microvascular complications (neuropathy, retinopathy, and nephropathy) in a cohort of Iranian patients with type 2 diabetes.

Methods

For a total population of 3123 patients with type 2 diabetes, a prospective study was designed for 1215 patients with NAFLD and 1908 gender and age-matched control patients without NAFLD. The two groups were followed for a median duration of 5 years for the incidence of microvascular complications. The association between having NAFLD, the level of liver enzymes, aspartate aminotransferase to platelet ratio index (APRI), Fibrosis-4 (FIB-4) value, and the incidence risk of diabetic retinopathy, neuropathy, and nephropathy were assessed through logistic regression analysis.

Results

NAFLD was found to be associated with incidence of diabetic neuropathy and nephropathy (Odds ratio: 1.338 (95% confidence interval: 1.091-1.640) and 1.333 (1.007-1.764), respectively). Alkaline-phosphatase enzyme was found to be associated with higher risks of diabetic neuropathy and nephropathy ((Risk estimate: 1.002 (95% CI: 1.001-1.003) and 1.002 (1.001-1.004), respectively)). Moreover, gamma-glutamyl transferase was associated with a higher risk of diabetic nephropathy (1.006 (1.002-1.009). Aspartate aminotransferase and alanine aminotransferase were inversely associated with the risk of diabetic retinopathy (0.989 (0.979-0.998) and 0.990 (0.983-0.996), respectively). Furthermore, ARPI_T (1), ARPI_T (2), and ARPI_T (3) were shown to be associated with NAFLD (1.440 (1.061-1.954), 1.589 (1.163-2.171), and 2.673 (1.925, 3.710), respectively). However, FIB-4 score was not significantly associated with risk of microvascular complications.

Conclusion

Despite the benign nature of NAFLD, patients with type 2 diabetes should be always assessed for NAFLD to ensure early diagnosis and entry into proper medical care. Regular screenings of microvascular complications of diabetes is also suggested for these patients.

Association between nonalcoholic fatty liver disease and peripheral neuropathy in US population, a cross-sectional study

Nonalcoholic fatty liver disease (NAFLD) has become an important risk of type 2 diabetes mellitus (T2DM). Peripheral neuropathy (PN) is regarded as one of the main microvascular complications of diabetes. But the association of NAFLD with PN is still unclear. We aimed to investigate the association between NAFLD and PN in US population by conducting a cross-sectional study. We enrolled 3029 participants aged 40-85 years from National Health and Nutrition Examination Survey (NHANES) 1999-2004. NAFLD was defined as a US Fatty Liver Index (FLI) score ≥ 30, and PN was defined as having one or more insensate areas on either foot. Participants were divided into two groups (with or without PN). We performed multivariate logistic regression models to evaluate the association between NAFLD and PN. Subgroup analyses were used to find out whether the association was stable in different stratified groups. Sensitivity analyses were conducted to assess the robustness of the results. All the analyses were weighted. Among the individuals, 524 (17.3%) had PN and 1250 (41.27%) had NAFLD. In the multivariate logistic regression models, NAFLD was associated with an increased risk of PN (OR 1.44 [1.03 ~ 2.02]) after fully adjusting for covariates. In the subgroup analyses, NAFLD was significantly associated with PN in the age group (40-64 years), compared with those in the age group (65-85 years), (P for interaction: 0.004). The results of association of NAFLD with PN were stable in sensitivity analyses. In this cross-sectional study among US adults aged 40-85 years old, NAFLD was associated with an increased likelihood of prevalent PN.

Non-alcoholic fatty liver disease and complications in type 1 and type 2 diabetes: A Mendelian randomization study

AIM

To investigate the potential causal relationship between non-alcoholic fatty liver disease (NAFLD) and complications in type 1 diabetes (T1D) and type 2 diabetes (T2D).

MATERIALS AND METHODS

Two-sample Mendelian randomization (MR) analysis was conducted to appraise after controlling for the confounding factors. Genetic instrument variables for NAFLD surrogated by chronically elevated serum alanine transferase were derived from a recent genome-wide association study. Diabetes-related complications, including diabetic ketoacidosis, nephropathy and retinopathy, were included as outcomes. Four complementary MR methods were used to test reliability.

RESULTS

Genetically instrumented NAFLD showed a suggestive causal association with ketoacidosis in T1D (odds ratio [OR]: 1.574; 95% confidence interval [CI]: 1.076, 2.302; P = .019; false discovery rate [FDR] = 0.096) and a significant causal association with early-stage kidney disease in T1D (OR: 1.249; 95% CI: 1.089, 1.432; P = 1.457 × 10^-3 , FDR = 0.015). Sensitivity analysis indicated low heterogeneity, low pleiotropy and high reliability of the causal estimates. However, the MR analyses failed to show a causal association between NAFLD and T1D retinopathy, T2D ketoacidosis, nephropathy and retinopathy.

CONCLUSIONS

This study supports a causal effect of genetically driven chronic serum alanine aminotransferase-associated NAFLD on early-stage kidney disease in T1D and a suggestive causal effect on ketoacidosis in T1D. However, MR studies did not provide enough evidence to suggest that NAFLD independently increases the risk of retinopathy in T1D and of ketoacidosis, nephropathy and retinopathy in T2D.

The association of alanine aminotransferase and diabetic microvascular complications: A Mendelian randomization study

AIMS

Alanine aminotransferase (ALT) is positively related to diabetes risk in observational studies, whereas Mendelian randomization supports a linear causal association. In contrast, the relationship between ALT and diabetic nephropathy, and diabetic retinopathy is counter-intuitive in observational studies. Furthermore, no MR study has examined their causal association. The study aimed to investigate whether genetically determined ALT has a causal effect on diabetic nephropathy and diabetic retinopathy.

METHODS

Genetic instruments associated with ALT (P < 5×10^-8) were obtained from a recent genome-wide association study (GWAS) that included 437,267 individuals of European ancestry. Summary data of diabetic microvascular complications were derived from the FinnGen study (3,283 cases and 181,704 controls for diabetic nephropathy, and 14,584 cases and 176,010 controls for diabetic retinopathy, both were of European ancestry). Effect estimation and pleiotropy testing were performed using inverse variance weighted (IVW), MR-Egger regression, weighted median, and mode-based estimator methods. We additionally performed sensitivity analysis excluding proxy single nucleotide polymorphisms (SNPs) or lowering the GWAS significance threshold (P < 5×10^-7) to test the robustness of the results.

RESULTS

Based on IVW, a 2-fold increase in genetically determined ALT level was positively associated with diabetic nephropathy (odd ratio, [95% confidence interval], 1.73 [1.26-2.37], P = 0.001) and diabetic retinopathy (1.29 [1.08-1.54], P = 0.005), but a null causal association in three pleiotropy robust methods, namely, MR-Egger, weighted median and mode-based estimator. We obtained similar results in the sensitivity analysis of excluding proxy SNPs or lowering the GWAS significance threshold.

CONCLUSIONS

With caution, we concluded that ALT plays no linear causal role in developing both diabetic nephropathy and diabetic retinopathy. Further investigations are required to test the hypothesis of a non-linear causal association.

The presence of diabetic retinopathy closely associated with the progression of non-alcoholic fatty liver disease: A meta-analysis of observational studies

Background and Objective: Although growing evidence indicates that non-alcoholic fatty liver disease is related to diabetic retinopathy (DR), research results significantly vary. Therefore, we conducted a meta-analysis to assess the association between the progression of non-alcoholic fatty liver disease and the onset of DR. Methods: PubMed, Embase, and Cochrane databases were searched until 7 November 2021. Combined odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the association. Results: We identified 18 studies involving 12,757 patients. The pooled effect assessment showed that liver fibrosis was positively correlated with DR (OR = 1.69, 95%CI 1.30-2.20; p < 0.0001); non-alcoholic fatty liver disease was not associated with the risk of DR (OR = 1.15, 95%CI 0.75-1.76; p = 0.51); non-alcoholic fatty liver disease was positively correlated with DR in patients with type 1 diabetes (OR = 2.96, 95%CI 1.48-5.94; p = 0.002). In patients with type 2 diabetes, there was no association between non-alcoholic fatty liver disease and DR (OR = 0.92, 95%CI 0.59-1.43; p = 0.70). Subgroup analysis showed no correlation in both Asian and Caucasian races. Conclusion: There is a significant correlation between liver fibrosis and DR. This suggests that the ocular examination of DR could be helpful in predicting whether patients with non-alcoholic fatty liver disease would progress to liver fibrosis.

Beyond the Liver: Liver-Eye Communication in Clinical and Experimental Aspects

The communication between organs participates in the regulation of body homeostasis under physiological conditions and the progression and adaptation of diseases under pathological conditions. The communication between the liver and the eyes has been received more and more attention. In this review, we summarized some molecular mediators that can reflect the relationship between the liver and the eye, and then extended the metabolic relationship between the liver and the eye. We also summarized some typical diseases and phenotypes that have been able to reflect the liver-eye connection in the clinic, especially non-alcoholic fatty liver disease (NAFLD) and diabetic retinopathy (DR). The close connection between the liver and the eye is reflected through multiple pathways such as metabolism, oxidative stress, and inflammation. In addition, we presented the connection between the liver and the eye in traditional Chinese medicine, and introduced the fact that artificial intelligence may use the close connection between the liver and the eye to help us solve some practical clinical problems. Paying attention to liver-eye communication will help us have a deeper and more comprehensive understanding of certain communication between liver diseases and eyes, and provide new ideas for their potential therapeutic strategy.

Association Between the Risk of Non-Alcoholic Fatty Liver Disease in Patients with Type 2 Diabetes and Chronic Kidney Disease

OBJECTIVE

To explore the relationship between non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 1168 patients with T2DM were divided into the non-CKD and CKD groups, and the difference in the prevalence of NAFLD was compared. The differences in serum creatinine (SCr) and urine albumin-to-creatinine ratio (UACR) levels were compared between the non-NAFLD and NAFLD groups. Patients with T2DM were divided into three groups according to their UACR levels (UACR < 30 mg/g [U1 group]; UACR ≤ 30 mg/g to < 300 mg/g [U2 group]; and UACR ≥ 300 mg/g [U3 group]) or estimated glomerular filtration rate (eGFR) levels (≥ 90 mL/min [G1 group]; eGFR ≤ 60 mL/min to < 90 mL/min [G2 group]; and eGFR < 60 mL/min (G3 group]). The difference in the prevalence and risks of NAFLD in the different UACR or eGFR level groups was analyzed.

RESULTS

The prevalence of NAFLD in the CKD group was higher than that in the non-CKD group (63.5% vs 50.5%, p < 0.001). The SCr and UACR levels in the NAFLD group were higher than those in the non-NAFLD group (both p<0.05). The prevalence of NAFLD in the U3 group (75.6%) was higher than that in the U1 (50.5%, p < 0.05) and U2 (60.1%, p < 0.05) groups, and the prevalence of NAFLD in the U2 group (60.1%) was higher than that in the U1 group (50.5%, p < 0.05). The risk of NAFLD in the U3 group was higher than that in the U2 group (odds ratio [OR] = 3.032 and 1.473). Despite adjusting the parameters further, the NAFLD risk in the U3 group remained higher than that in the U2 group (OR = 1.660 and 2.342).

CONCLUSION

The risk of NAFLD in patients with T2DM is closely related to CKD.

Metabolic-Associated Fatty Liver Disease (MAFLD), Diabetes, and Cardiovascular Disease: Associations with Fructose Metabolism and Gut Microbiota

Non-alcoholic fatty liver disease (NAFLD) is an increasingly common condition associated with type 2 diabetes (T2DM) and cardiovascular disease (CVD). Since systemic metabolic dysfunction underlies NAFLD, the current nomenclature has been revised, and the term metabolic-associated fatty liver disease (MAFLD) has been proposed. The new definition emphasizes the bidirectional relationships and increases awareness in looking for fatty liver disease among patients with T2DM and CVD or its risk factors, as well as looking for these diseases among patients with NAFLD. The most recommended treatment method of NAFLD is lifestyle changes, including dietary fructose limitation, although other treatment methods of NAFLD have recently emerged and are being studied. Given the focus on the liver-gut axis targeting, bacteria may also be a future aim of NAFLD treatment given the microbiome signatures discriminating healthy individuals from those with NAFLD. In this review article, we will provide an overview of the associations of fructose consumption, gut microbiota, diabetes, and CVD in patients with NAFLD.

Association of Nonalcoholic Fatty Liver Disease (NAFLD) with Peripheral Diabetic Polyneuropathy: A Systematic Review and Meta-Analysis

AIMS

The relationship between nonalcoholic fatty liver disease (NAFLD) and diabetic polyneuropathy (DPN) has been demonstrated in many studies, although results were conflicting. This meta-analysis aims to summarize available data and to estimate the DPN risk among NAFLD patients.

MATERIALS AND METHODS

We performed a comprehensive literature review until 4 June 2021. Clinical trials analyzing the association between NAFLD and DPN were included.

RESULTS

Thirteen studies (9614 participants) were included. DPN prevalence was significantly higher in patients with NALFD, compared to patients without NAFLD (OR (95%CI) 2.48 (1.42-4.34), p = 0.001; I2 96%). This finding was confirmed in type 2 diabetes (OR (95%CI) 2.51 (1.33-4.74), p = 0.005; I2 97%), but not in type 1 diabetes (OR (95%CI) 2.44 (0.85-6.99), p = 0.100; I2 77%). Also, body mass index and diabetes duration were higher in NAFLD subjects compared to those without NAFLD (p < 0.001), considering both type 2 and type 1 diabetes.

CONCLUSION

Despite a high heterogeneity among studies, a significantly increased DPN prevalence among type 2 diabetes subjects with NAFLD was observed. This result was not found in type 1 diabetes, probably due to the longer duration of disease. Physicians should pay more attention to the early detection of DPN, especially in patients with NAFLD.

Importance of non-invasive liver fibrosis scores for mortality and complications development in individuals with type 2 diabetes

AIMS

To evaluate the non-alcoholic fatty liver disease (NAFLD) fibrosis score (NFS) and Fibrosis-4 score (FIB4) as predictors of complications development and mortality in a cohort of type 2 diabetes.

METHODS

554 type 2 diabetic subjects had NFS and FIB4 calculated at baseline. Multivariate Cox and Poisson analyses evaluated the associations between fibrosis scores and the occurrence of microvascular and cardiovascular complications, and all-cause mortality.

RESULTS

According to recommended cut-offs of NFS, 12.8% had advanced fibrosis and 45.9% had absence of advanced fibrosis and of FIB4, 3.8% and 86.1%, respectively. During a median follow-up of 11 years, 217subjects died, 172 had cardiovascular events (CVEs), 184 had renal events, and 139 had retinopathy and 185 neuropathy events. As continuous variables, both scores predicted all-cause mortality: NFS, HR: 1.30 (p = 0.032) and FIB4, HR: 1.24 (p = 0.021); an increased NFS implied in a significant 90% excess risk of mortality, whereas a higher FIB4 in a borderline 69% higher risk. The scores were mainly predictors of mortality in women and for non-cardiovascular deaths. The NFS was a predictor of renal events, mainly for renal function deterioration.

CONCLUSIONS

The NFS and FIB4 predicted all-cause mortality, particularly in women and for non-cardiovascular causes. The NFS predicted adverse renal outcomes. These liver fibrosis scores may improve stratification risk in individuals with diabetes and NAFLD.

Association of non-alcoholic fatty liver disease with diabetic retinopathy in type 2 diabetic patients: A meta-analysis of observational studies

Aims/Introduction

Non‐alcoholic fatty liver disease (NAFLD) is becoming more and more prevalent in type 2 diabetes mellitus. Evidence connecting NAFLD to diabetic retinopathy (DR) is increasing, but the results vary. Thus, we undertook a meta‐analysis to explore the effect of NAFLD on diabetic retinopathy in patients with type 2 diabetes mellitus.

Materials and Methods

PubMed, Embase, Cochrane and Scopus database were searched for until September 30, 2019. Original studies analyzing the association between NAFLD and diabetic retinopathy in the type 2 diabetic population were included. This meta‐analysis was processed by RevMan 5.3 software. Subgroup analyses based on countries were carried out. The pooled odds ratios and 95% confidence intervals were used to evaluate the association between NAFLD and diabetic retinopathy incidence. The I² test was used to assess heterogeneity of studies.

Results

We retrieved 414 articles, and nine studies involving 7,170 patients were included in the final analysis. The pooled effects estimate suggested that NAFLD was not associated with the risk of diabetic retinopathy in patients with type 2 diabetes mellitus. Subgroup analysis suggested that in China, Korea and Iran, patients with type 2 diabetes mellitus with NAFLD had a decreased risk for diabetic retinopathy compared with the non‐NAFLD individuals. However, in Italy and India, patients with type 2 diabetes mellitus with NAFLD had an increased risk for diabetic retinopathy compared with the non‐NAFLD individuals. In addition, no relevance between NAFLD and diabetic retinopathy was found in America.

Conclusions

On the whole, there was no association between NAFLD and diabetic retinopathy in individuals with type 2 diabetes mellitus. However, subgroup analysis showed that a difference of country may have an influence on the result.

Association between hemoglobin levels and non-alcoholic fatty liver disease in patients with young-onset type 2 diabetes mellitus

This retrospective study aimed to investigate the relationship between hemoglobin (Hb) levels and non-alcoholic fatty liver disease (NAFLD) in patients with young-onset type 2 diabetes mellitus (T2DM). Data were collected for 296 patients with young-onset T2DM admitted to the first Affiliated Hospital of Guangxi Medical University from May 2017 to January 2020. Subjects were divided into NAFLD (n = 186) and non-NAFLD groups (n = 110). Patients with NAFLD had significantly higher Hb levels (p = 0.001). According to logistic regression analysis, Hb levels were significantly correlated with NAFLD after adjusting for confounding factors [odds ratio (OR) = 1.024, 95% confidence interval = 1.003-1.046, p = 0.028]. Subjects were also grouped according to Hb quartiles. After adjusting for sex and body mass index (BMI), the OR (95%CI) for NAFLD significantly increased with increasing Hb levels (p for trend = 0.009). Patients were also divided into lean (BMI <25 kg/m², n = 139) and overweight/obese groups (BMI ≥25 kg/m², n = 157), with adjusted ORs (95%CI) for the highest quartiles of 1.797 (0.559-5.776) and 6.009 (1.328-27.181), respectively. Further quartile classification of Hb according to sex showed adjusted OR (95%CI) for the highest compared with the lowest quartile of 2.796 (1.148-6.814) for males and 2.945 (0.482-17.997) for females. In conclusion, high Hb levels were associated with the presence of NAFLD in patients with young-onset T2DM, especially in males and overweight/obese patients.