Vitamin D deficiency in non-alcoholic fatty liver disease: The chicken or the egg? Clin Nutr. 2015; Epub ahead of print. [PMID: 26615912 DOI: 10.1016/j.clnu.2015.10.017]

Metabolic Dysfunction-Associated Steatotic Liver Disease Increases the Risk of Severe Infection: A Population-Based Cohort Study

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD) is linked to various intrahepatic and extrahepatic diseases, but its association with severe infectious disease remains to be investigated.

METHODS

We analysed data from the Shanghai Suburban Adult Cohort and Biobank, encompassing participants enrolled in 2016 and 2017 with available abdominal ultrasonography data, and followed them up until December 2022 (median follow-up = 5.71 years). We categorised the participants into the MASLD group and those without steatotic liver disease (non-SLD). Multivariable-adjusted Cox regression was used to estimate hazard ratios (HR) for severe infections in patients with MASLD compared to the non-SLD group. Cumulative incidences were calculated while accounting for competing risks (non-infection-related deaths). Mediation analyses were performed to explore the roles of cardiometabolic risk factors in the association between MASLD and severe infections.

RESULTS

Among the 33 072 eligible participants (mean age 56.37 years; 38.20% male), 11 908 (36.01%) were diagnosed with MASLD at baseline. Severe infections occurred in 912 (7.66%) MASLD patients and 1258 (5.94%) non-SLD. The rate of severe infections per 1000 person-years was higher in MASLD patients (13.58) than in comparators (10.48) (fully adjusted HR 1.18, 95% CI 1.07-1.30). The most frequent infections in MASLD were respiratory (7.25/1000 person-years) and urinary tract infections (2.61/1000 person-years). The 5-year cumulative incidence of severe infections was 6.79% (95% CI 6.36-7.26) in MASLD and 5.08% (95% CI 4.79-5.38) in comparators. Cardiometabolic risk factors, including waist circumference, triglycerides and HbA1C, partially mediate the association between MASLD and severe infections.

CONCLUSIONS

Patients with MASLD were at significantly higher risk of incident severe infections compared to the non-SLD group. Future studies are needed to elucidate the mechanisms linking MASLD to severe infections.

The Triglyceride-Glucose Index is Associated with Vitamin D Status in Metabolic-Associated Fatty Liver Disease

Purpose

Vitamin D deficiency was thought to be associated with insulin resistance and metabolic-associated fatty liver disease (MAFLD). The aim of this study was to investigate the relationship between the triglyceride-glucose (TyG) index, a useful surrogate biomarker of insulin resistance, and vitamin D status in patients with MAFLD.

Patients and Methods

A total of 566 patients with MAFLD were included in this retrospective cross-sectional study. Clinical characteristics were compared between participants with and without vitamin D deficiency. The association between the TyG index and serum 25-hydroxyvitamin D [25(OH)D] levels was determined by Spearman correlation analysis and logistic regression analysis. The receiver operating characteristic curve (ROC) was used to assess the diagnostic efficacy of TyG index for vitamin D deficiency in MAFLD patients.

Results

The TyG index levels were higher in the vitamin D deficient group than in the non-vitamin D deficient group, and serum 25(OH)D was negatively correlated with the TyG index. The TyG index was an independent risk factor for vitamin D deficiency in patients with MAFLD. The area under the curve (AUC) of the TyG index for the identification of vitamin D deficiency in MAFLD patients was 0.744 (95% CI: 0.701-0.787, p<0.001).

Conclusion

The TyG index is negatively associated with vitamin D status in patients with MAFLD. In patients with MAFLD, a higher TyG index may be an indication of a higher prevalence of vitamin D deficiency.

Antibiotics and Liver Cirrhosis: What the Physicians Need to Know

The liver is the primary site of drug metabolism, which can be altered by a variety of diseases affecting the liver parenchyma, especially in patients with liver cirrhosis. The use of antibiotics in patients with cirrhosis is usually a matter of concern for physicians, given the lack of practical knowledge for drug choice and eventual dose adjustments in several clinical scenarios. The aim of the current narrative review is to report, as broadly as possible, basic, and practical knowledge that any physician should have when approaching a patient with liver cirrhosis and an ongoing infection to efficiently choose the best antibiotic therapy.

Association and interaction between vitamin D level and metabolic syndrome for non-alcoholic fatty liver disease

INTRODUCTION/OBJECTIVES

Previous studies have shown conflicting results regarding the association between hypovitaminosis D and non-alcoholic fatty liver disease (NAFLD). The aim of this study is to explore the individual and combined effect of hypovitaminosis D and metabolic syndrome (MS) on NAFLD.

MATERIALS AND METHODS

In this cross-sectional study, 874 subjects were enrolled. 25(OH)D was assessed by a sequential competitive immuno-fluoro-assay method. The Fatty Liver Index (FLI) was used for NAFLD screening. Binary logistic regression and additive interaction were performed to investigate the association between vitamin D status, MS and NAFLD.

RESULTS

Severe vitamin D deficiency was found to be positively related to NAFLD, with a higher risk in women than in men (OR = 6.4, 95% CI [2.8-15], p < 0.0001 vs. OR = 5.8, 95% CI [1.9-17.7], p = 0.002). In men, this association was partially masked by obesity. The additive interaction with MS was significant in women but not in men, the relative excess risk due to interaction was of 7.2, 95% CI [1.3-12.9], p = 0.02), the attributable proportion due to the combined effect was of 0.6, 95% CI [0.4-0.8], p < 0.0001. The interaction mechanism is synergistic; the synergy index: was of 2.9, 95% CI [1.6-5.3], p = 0.0006.

CONCLUSION

A positive association has been found between severe vitamin D deficiency and NAFLD. Moreover, an excess risk in women combining both MS and severe vitamin D deficiency was quantified.

The Role of Vitamin Deficiency in Liver Disease: To Supplement or Not Supplement?

Over the past few years, growing interest has been shown for the impact of dietary requirements and nutritional factors on chronic diseases. As a result, nutritional programs have been reinforced by public health policies. The precise role of micronutrients in chronic liver disease is currently receiving particular attention since abnormalities in vitamin levels are often detected. At present, treatment programs are focused on correcting vitamin deficiencies, which are frequently correlated to higher rates of comorbidities with poor outcomes. The literature reviewed here indicates that liver diseases are often related to vitamin disorders, due to both liver impairment and abnormal intake. More specific knowledge about the role of vitamins in liver disease is currently emerging from various results and recent evidence. The most significant benefits in this area may be observed when improved vitamin intake is combined with a pharmacological treatment that may also affect the progression of the liver disease, especially in the case of liver tumors. However, further studies are needed.

NAFLD and Infection, a Nuanced Relationship

The prevalence of nonalcoholic fatty liver disease (NAFLD) has increased significantly over the last few decades mirroring the increase in obesity and type II diabetes mellitus. NAFLD has become one of the most common indications for liver transplantation. The deleterious effects of NAFLD are not isolated to the liver only, for it has been recognized as a systemic disease affecting multiple organs through protracted low-grade inflammation mediated by the metabolic activity of excessive fat tissue. Extrahepatic manifestations of NAFLD such as cardiovascular disease, polycystic ovarian syndrome, chronic kidney disease, and hypothyroidism have been well described in the literature. In recent years, it has become evident that patients suffering from NAFLD might be at higher risk of developing various infections. The proposed mechanism for this association includes links through hyperglycemia, insulin resistance, alterations in innate immunity, obesity, and vitamin D deficiency. Additionally, a risk independent of these factors mediated by alterations in gut microbiota might contribute to a higher burden of infections in these individuals. In this narrative review, we synthetize current knowledge on several infections including urinary tract infection, pneumonia, Helicobacter pylori, coronavirus disease 2019, and Clostridioides difficile as they relate to NAFLD. Additionally, we explore NAFLD's association with hidradenitis suppurativa.

Vitamin D Level and Vitamin D Receptor Genetic Variation Were Involved in the Risk of Non-Alcoholic Fatty Liver Disease: A Case-Control Study

BACKGROUND

It has been demonstrated that vitamin D receptor (VDR), a key gene in the metabolism of vitamin D (VD), may affect the development of Non-alcoholic fatty liver disease (NAFLD) by regulating VD level and its biological effects.

OBJECTIVES

To investigate the effects of serum VD level, VDR variation, and a combination of VDR SNP and environmental behavior factor on the risk of NAFLD.

METHODS

A total of 3023 subjects from a community in Nanjing were enrolled, including 1120 NAFLD cases and 1903 controls. Serum 25(OH)D₃ levels were measured and eight single nucleotide polymorphisms (SNPs) in VDR gene were genotyped.

RESULTS

Logistic regression analyses indicated that VD sufficiency and VD insufficiency were significantly associated with a low risk of NAFLD (all P<0.05; all P_trend<0.05, in a locus-dosage manner). After adjusting for gender and age, VDR rs2228570-A and rs11168287-A alleles were all reduced the risk of NAFLD (all P_FDR=0.136, in dominant model; P_trend =0.039, combined effects in a locus-dosage manner). The protective effects of two favorable alleles were more evident among subjects ≤40 years, non-hypertension, non-hyperglycemia and non-low high density lipoprotein-cholesterol (all P<0.05). The area under the receiver operating curve of the combination of VDR SNP and exercise time for assessing NAFLD risk was slightly higher than that of only including exercise time or neither (all P<0.05).

CONCLUSION

High serum VD levels and VDR variants (rs2228570-A and rs11168287-A) might contribute to a low risk of NAFLD in Chinese Han population. The inclusion of VDR SNP and exercise time could improve the efficiency in assessment of NAFLD risk, which might provide a novel perspective for early screening and preventing NAFLD.

Effects of vitamin D supplements in patients with chronic hepatitis C: a randomized, multi-center, open label study

BACKGROUND/AIMS

We aimed to assess the role of vitamin D supplementation in the response to pegylated interferon-α (PEG-IFN-α) plus ribavirin (RBV) treatment in patients with chronic hepatitis C (CHC).

METHODS

Our study was a multi-center, randomized controlled trial in 11 hospitals. CHC patients were randomly assigned (1:1) to two groups namely, PEGIFN-α plus RBV (control group) or PEG-IFN-α plus RBV + vitamin D (800 IU daily) (vitamin D group). The primary end-point was the rate of sustained virologic response (SVR).

RESULTS

One hundred forty eight CHC patients were randomly assigned to two groups. Seventy-one patients received the PEG-IFN-α plus RBV and 77 patients received the PEG-IFN-α plus RBV + vitamin D. A total of 105 patients completed the study (control group, 47 vs. vitamin D group, 58). Baseline characteristics were mostly similar in both the groups. There was a modest but non-significant increase in SVR in the vitamin D group compared to the control group with the intention to treat analysis (64.0% vs. 49.3 %, p = 0.071) as well as in the per protocol analysis (control group vs. vitamin D group: 74.5% vs. 84.5%, p = 0.202). Fifty-two patients (73.2%) in the control group and 63 patients (81.8%) in the vitamin D group experienced at least one adverse event. The drop-out rate due to adverse effects was not different between both groups (control group vs. vitamin D group: 19.7% vs. 10.4%, p = 0.111).

CONCLUSION

Vitamin D supplement did not increase SVR in treatment naïve patients with CHC irrespective of genotype.

Association Between Index of Nutritional Quality and Nonalcoholic Fatty Liver Disease: The Role of Vitamin D and B Group

BACKGROUND

Numerous studies have revealed that diet has been considered as an important pathogenic factor for nonalcoholic fatty liver disease (NAFLD). The Index of Nutritional Quality (INQ) is a method of quantitative and qualitative evaluation of single foods and diets, which has special significance in recognizing clinical nutritional problems.

MATERIALS AND METHODS

This study included 295 patients with NAFLD and 704 controls. The dietary intake was assessed through a valid and reliable food frequency questionnaire. INQ was calculated from the questionnaire data and was compared between the 2 groups.

RESULTS

The controls had higher INQ of vitamin D, vitamin E, thiamin, riboflavin, niacin, vitamin B12; biotin, pantothenic acid, magnesium and zinc compared to the patients with NAFLD. After controlling for several covariates, positive associations were observed between NAFLD risk and INQs of riboflavin (OR_riboflavin = 0.49, 95% confidence interval [CI]: 0.28-0.78; OR_biotin = 0.35, 95% CI: 0.18-0.76; OR_pantothenic = 0.28, 95% CI: 0.12-0.64; OR_magnesium = 0.28, 95% CI: 0.11-0.75; OR_zinc = 0.15 95% CI: 0.05-0.42).

CONCLUSIONS

Findings of the present study suggest that subjects who follow a more healthy and nutrient-rich diet, especially in terms of vitamins D, B1, B2, B12, B3 and zinc, are at a lower risk of NAFLD compared to those who consume unhealthy and nutrient-poor diet.

Association of vitamin D levels and vitamin D-related gene polymorphisms with liver fibrosis in patients with biopsy-proven nonalcoholic fatty liver disease

BACKGROUND

Vitamin D has promising anti-proliferative and anti-fibrotic properties, but its clinical utility in nonalcoholic fatty liver disease (NAFLD) is unclear.

AIMS

This study aimed to clarify the association between vitamin D levels, single nucleotide polymorphisms (SNPs) in vitamin D-related genes, and the histopathological severity of disease in patients with biopsy-proven NAFLD.

METHODS

SNPs in CYP2R1, DHCR7, vitamin D binding protein (GC), CYP27B1, and vitamin D receptor (VDR) were determined for 229 consecutive patients with biopsy-proven NAFLD.

RESULTS

In this study, vitamin D deficiency defined as 25-hydroxyvitamin-D₃ levels of ≤20 ng/mL was found in 151 patients (65.9%). Multivariate analysis revealed that cold season, advanced fibrosis, and CYP2R1 rs1993116 genotype non-AA were independent factors significantly associated with vitamin D deficiency. Old age (p = 5.05 × 10^-8), high body mass index (p = 2.13 × 10^-2), low total-cholesterol (p = 1.46 × 10^-4), low serum vitamin D level (p = 7.34 × 10^-3), and VDR rs1544410 genotype CC (p = 9.15 × 10^-3) were independent factors associated with advanced liver fibrosis.

CONCLUSION

Serum 25-hydroxyvitamin-D₃ levels and the VDR gene SNP were significantly and independently associated with the severity of liver fibrosis in patients with biopsy-proven NAFLD.

Vitamin D and the Liver-Correlation or Cause?

Vitamin D is becoming increasingly accepted as an important physiological regulator outside of its classical role in skeletal homeostasis. A growing body of evidence connects vitamin D with hepatic disease. This review summarises the role of vitamin D in liver homeostasis and disease and discusses the therapeutic potential of vitamin D-based treatments to protect against hepatic disease progression and to improve response to treatment. While pre-clinical experimental data is promising, clinical trials around liver diseases have mostly been under-powered, and further studies will be required to clarify whether vitamin D or vitamin D analogues have beneficial effects on liver disease.

Attenuating the rate of total body fat accumulation and alleviating liver damage by oral administration of vitamin D-enriched edible mushrooms in a diet-induced obesity murine model is mediated by an anti-inflammatory paradigm shift

Background

Hypovitaminosis D is associated with many features of the metabolic syndrome, including non-alcoholic fatty liver disease. Vitamin D-enriched mushrooms extracts exert a synergistic anti-inflammatory effect. The aim of the present study is to determine the immunomodulatory effect of oral administration of vitamin D-enriched mushrooms extracts on high-fat diet (HFD) animal model of non-alcoholic steatohepatitis (NASH).

Methods

C57BL/6 mice on HFD were orally administered with vitamin D supplement, Lentinula edodes (LE) mushrooms extract, or vitamin D-enriched mushrooms extract for 25 weeks. Mice were studied for the effect of the treatment on the immune system, liver functions and histology, insulin resistance and lipid profile.

Results

Treatment with vitamin D-enriched LE extracts was associated with significant attenuation of the rate of total body fat accumulation, along with a decrease in hepatic fat content as measured by an EchoMRI. Significant alleviation of liver damage manifested by a marked decrease in ALT, and AST serum levels (from 900 and 1021 U/L in the control group to 313 and 340; 294 and 292; and 366 and 321 U/L for ALT and AST, in Vit D, LE and LE + Vit D treated groups, respectively). A corresponding effect on hepatocyte ballooning were also noted. A significant decrease in serum triglycerides (from 103 to 75, 69 and 72 mg/dL), total cholesterol (from 267 to 160, 157 and 184 mg/dL), and LDL cholesterol (from 193 mg/dL to 133, 115 and 124 mg/dL) along with an increase in the HDL/LDL ratio, and improved glucose levels were documented. These beneficial effects were associated with a systemic immunomodulatory effect associated with an increased CD4/CD8 lymphocyte ratio (from 1.38 in the control group to 1.69, 1.71 and 1.63), and a pro- to an anti-inflammatory cytokine shift.

Conclusions

Oral administration of vitamin-D enriched mushrooms extracts exerts an immune modulatory hepato-protective effect in NASH model.

Neglected features of lifestyle: Their relevance in non-alcoholic fatty liver disease

AIM

To investigated in non-alcoholic-fatty-liver-disease (NAFLD), with ultrasound (US)-detected fatty liver, and in a group of non-alcoholic and otherwise healthy subjects, relationship of neglected features of lifestyle with NAFLD and obesity.

METHODS

Five hundred and thirty-two NAFLD and 667 non-NAFLD healthy subjects, age 21-60 years were studied. Severity of liver steatosis was assessed by US bright liver score. The adherence to mediterranean diet score (AMDS) was assessed on the basis of a 1-wk recall computerized questionnaire which included a detailed physical activity reports (Baecke questionnaire). The western dietary profile score, as a simplified paradigm of unhealthy diet, a questionnaire quantifying sun exposure score and a sleep habits questionnaires provided a further comprehensive lifestyle assessment.

RESULTS

Body mass index (BMI), insulin resistance (HOMA), and triglycerides, poorer adherence to a mediterranean diet profile, sedentary habits, minor sun exposure and use of “western diet” foods are greater in NAFLD. Multiple linear regression analysis, weighted by years of age, displays BMI, HOMA and AMDS as the most powerful independent predictors of fatty liver severity; however, also the physical activity score, the western diet habit and the sun exposure score are acting inside the model with significant independent effects.

CONCLUSION

Articulated clinical intervention, according to our results, are justified in NAFLD and can be pursued addressing by focused intervention nutritional profile, physical exercise mainly in open-air subsets for enhancing sun exposure and healthier sleep duration and rhythm.

High levels of serum vitamin D are associated with a decreased risk of metabolic diseases in both men and women, but an increased risk for coronary artery calcification in Korean men

Background

There are conflicting results for relationships between serum vitamin D levels and metabolic diseases. The aim of this study was to investigate whether serum vitamin D levels were associated with various metabolic diseases including insulin resistance (IR), metabolic syndrome (MS), fatty liver (FL), and coronary artery calcification (CAC), along with assessing gender differences for these relationships in Korean adults.

Methods

A total of 180,918 subjects (98,412 men and 82,506 women) who participated in a comprehensive health examination in the 2012–2013 period at Kangbuk Samsung Hospital, College of Medicine, Sungkyunkwan University were included. Serum vitamin D and metabolic markers were analyzed and CAC was estimated. Subjects were divided according to quartile groups of serum vitamin D. To examine the relationships of serum vitamin D to metabolic diseases and metabolic factors, multivariate logistic analysis was conducted.

Results

High levels of serum vitamin D was associated with lower ORs for MS, IR and FL both in men and women (all p < 0.05). For men, ORs for CAC were significantly higher in third and the highest quartile groups for serum vitamin D in all the analyzed models (all p < 0.05). However, women showed no significant results between serum vitamin D and CAC.

Conclusions

High levels of serum vitamin D were associated with lower risk of MS, IR and FL in both Korean men and women, but were associated with higher risk of CAC only in men, and not in women.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0432-3) contains supplementary material, which is available to authorized users.