Serum vitamin D levels are inversely related with non-alcoholic fatty liver disease independent of visceral obesity in Chinese postmenopausal women

Vitamin D levels and lipid profiles in patients with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women. Dyslipidemia is a prevalent metabolic abnormality in individuals with PCOS. Moreover, vitamin D deficiency is widespread across all societal strata, with a particularly heightened prevalence observed in patients afflicted with PCOS. The present study aimed to investigate the level of vitamin D and its correlation with lipid profiles in Iranian women diagnosed with PCOS.

METHODS

This cross-sectional study was carried out at the PCOS and infertility clinic of Arash Women's Hospital in Tehran. The study encompassed the medical records of PCOS patients who attended the clinic from March 2021 to December 2023. All patients underwent blood tests, which included assessments of fasting blood sugar levels, lipid profiles, and 25-hydroxyvitamin D (25(OH)D) levels. The investigation focused on evaluating the relationship between vitamin D levels and lipid profiles. Statistical analyses, including the chi-square test and Spearman's correlation coefficient, were employed to analyze the data.

RESULTS

A total of 1004 women diagnosed with PCOS were included in the study. The age range of the participants was 14 to 46 years. The majority of the participants had a body mass index (BMI) within the normal range (n = 555, 55.3%). The median vitamin D level among the participants was 26.00 (IQR: 19.00-34.00). The relationship between vitamin D levels and lipid profile parameters was assessed, revealing no significant correlation between vitamin D levels and low-density lipoprotein (LDL) (r = 0.021, p = 0.505), high-density lipoprotein (HDL) (r = 0.011, p = 0.719), or triglyceride (TG) (r = -0.026, p = 0.417) levels, both in non-adjusted and age-adjusted analyses.

CONCLUSION

According to the present study, there was no significant correlation between serum 25(OH)D deficiency and elevated TG or LDL levels or decreased HDL levels in PCOS patients. Nevertheless, further prospective studies are needed to determine whether there is a causal relationship between vitamin D deficiency and lipid profile alterations, specifically among PCOS patients.

Association between vitamin D deficiency and lipid profiles in overweight and obese adults: a systematic review and meta-analysis

OBJECTIVE

The association between vitamin D deficiency and lipid profiles in adults with overweight or obesity remains unclear and inconsistent. The aim of our study was to determine the relationship between lipid profiles and vitamin D deficiency in the overweight and obese adults.

METHODS

Four databases, including PubMed, the Web of Science, EMBASE and the Cochrane Library, were used to identify all studies on vitamin D status and lipid levels, including the serum levels of triglycerides (TGs), total cholesterol (TC), low-density lipoprotein cholesterol (LDL), and high-density lipoprotein cholesterol (HDL). The Weighted mean difference (WMD) with 95% confidence intervals (CIs) using random-effects models was used to assess the association between the lipid profile and vitamin D deficiency.

RESULTS

Twenty-one articles that included a total of 7952 adults with overweight or obesity (BMI ≥ 25 kg/m2) were included. The overall results revealed that compared with the controls, individuals with vitamin D deficiency showed higher levels of TG (WMD = 15.01; 95%CI, 2.51-27.52) and TC (WMD = 8.61; 95%CI, 1.31-15.92). Moreover, vitamin D deficiency was related to an increased level of LDL (WMD = 6.12; 95%CI, 0.02-12.23). HDL level was inversely associated with the vitamin D deficiency status (WMD = -2.57; 95%CI, -4.26, -0.88).

CONCLUSIONS

Among the adults with overweight or obesity, the vitamin D deficient group displayed impaired lipid profiles, including increased TG, TC and LDL levels and reduced HDL level.

Serum 25-hydroxyvitamin D levels and the risk of non-alcoholic fatty liver: A two-sample Mendelian randomization study

BACKGROUND

Accumulated studies have shown that low expression of 25-hydroxyvitamin D [25(OH)D] was significantly associated with the risk of non-alcoholic fatty liver disease (NAFLD). However, the exact causality is still unknown. The aim of this study was to investigate whether levels of 25(OH)D are associated with risk of NAFLD, using a two-sample Mendelian randomization (MR).

METHODS

Data from a recent large vitamin D genome-wide association study (GWAS) on 417,580 Europeans were utilized, and the largest published histology-based NAFLD GWAS study (1,483 cases and 17,781 healthy controls) for genetic variants predicted to cause NAFLD were searched. All genetic datasets for the MR analyses were obtained using publicly available summary statistics based on individuals of European ancestry from the MR-Base and NHGRI-EBI GWAS Catalog database. Inverse-variance weighted (IVW) MR approach was used to estimate causal effects in the main analysis, complemented by 4 additional methods to control for pleiotropy. Sensitivity analyses were conducted to verify whether heterogeneity and pleiotropy can bias the MR results.

RESULTS

The MR analysis did not provide strong evidence for the causal association of circulating 25(OH)D with NAFLD by IVW method (OR = 0.746, 95%CI 0.517-1.078; P = 0.119). The results were consistent using four other MR methods. Sensitivity analysis using all different analytical approaches yielded similar results. There was no evidence for pleiotropy (MR-Egger intercept: -0.0003758, P = 0.970). The replication process also showed consistent results using IVW method (P = 0.710).

CONCLUSION

This study indicates that serum 25(OH)D levels did not possess an obvious effect on the risk of NAFLD. The associations in previous studies may be due to residual confounding or reverse causation.

Serum 25-hydroxyvitamin D3 Levels and Diabetes in a Japanese Population: The DOSANCO Health Study

BACKGROUND

Both decreased insulin sensitivity and impaired insulin secretion are common in Asian populations with diabetes, in contrast to Western populations. There is limited evidence regarding the association between insulin response in diabetes in Asian populations and serum 25-hydroxyvitamin D₃ (25[OH]D₃) insufficiency.

METHODS

The present cross-sectional study compared the prevalence of diabetes, defined as a fasting plasma glucose level ≥126 mg/dL and/or a HbA1c level ≥6.5%, among 480 participants aged 35-79 years not taking anti-diabetes medications, based on serum 25(OH)D₃ levels. A logistic regression model was used to calculate the odds ratios for diabetes in each serum 25(OH)D₃ group. Furthermore, this study examined the association between serum 25(OH)D₃ levels and the index of homeostasis model assessment of insulin resistance (HOMA-IR) using a linear regression model.

RESULTS

The prevalence of diabetes was 7.29% in the study population, and was higher in lower serum 25(OH)D₃ quartile groups. The odds ratios for diabetes in the first, second, and third serum 25(OH)D₃ quartile groups (25[OH]D₃: ≤18.10, 18.11-22.90, and 22.91-28.17 ng/mL) were 4.02 (95% confidence interval [CI], 1.25-12.92), 2.50 (95% CI, 0.77-8.10), and 1.91 (95% CI, 0.60-6.09), respectively, with the fourth quartile group (⩾28.18 ng/mL) serving as the reference group, after adjusting for sociodemographic, lifestyle, physical and environmental factors. Serum 25(OH)D₃ levels showed an inverse association with log-transformed HOMA-IR after adjusting for similar factors (standardized β = -0.08; 95% CI, -0.14 to -0.02).

CONCLUSION

Serum 25(OH)D₃ levels were inversely associated with diabetes prevalence in a general Japanese population, with a slight inverse association between serum 25(OH)D₃ levels and HOMA-IR.

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.

Development and validation of a laboratory risk score for the early prediction of COVID-19 severity and in-hospital mortality

BACKGROUND AND AIMS

Coronavirus Disease 2019 is characterized by a spectrum of clinical severity. This study aimed to develop a laboratory score system to identify high-risk individuals, to validate this score in a separate cohort, and to test its accuracy in the prediction of in-hospital mortality.

METHODS

In this cohort study, biological data from 330 SARS-CoV-2 infected patients were used to develop a risk score to predict progression toward severity. In a second stage, data from 240 additional COVID-19 patients were used to validate this score. Accuracy of the score was measured by the area under the receiver operating characteristic curve (AUC).

RESULTS

In the development cohort, a step-wise decrease in the average survival duration was noted with the increment of the risk score (pANOVA < 0.0001). A similar trend was confirmed when analyzing this association in the validation cohort (p < 0.0001). The AUC was 0.74 [0.66-0.82] and 0.90 [0.87-0.94], p < 0.0001, respectively for severity and mortality prediction.

CONCLUSION

This study provides a useful risk score based on biological routine parameters assessed at the time of admission, which has proven its effectiveness in predicting both severity and short-term mortality of COVID-19. Improved predictive scores may be generated by including other clinical and radiological features.

Correlational study on the levels of 25-hydroxyvitamin D and non-alcoholic fatty liver disease in type 2 diabetic patients

BACKGROUND

It is widely acknowledged that nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus(T2DM) are all chronic metabolic diseases. The objective of this study is to retrospectively probe the association between the 25-hydroxyvitamin D (25-(OH)D) and NAFLD in type 2 diabetic patients.

METHODS

Three hundred thirty-nine T2DM patients participated in this research and from November 2018 to September 2019 and were divided into simple T2DM group (108 cases) and T2DM with NAFLD group (231 cases) in conformity with abdominal ultrasound diagnosis. The NAFLD fibrosis score (NFS) ≥0.676 was defined as progressive liver fibrosis.231 T2DM with NAFLD patients were categorized into two subgroups: progressive liver fibrosis subgroup (48 cases) and without progressive liver fibrosis subgroup (183 cases).

RESULTS

The prevalence of NAFLD by Abdominal ultrasonography was 68%.The results indicated that the levels of 25-(OH) D were significantly lower in T2DM with NAFLD group than that in simple T2DM group(P < 0.01). The levels of 25-(OH) D were significantly lower in progressive liver fibrosis subgroup than that in patients without progressive liver fibrosis and simple T2DM,and 25-(OH) D levels were lower in without progressive liver fibrosis subgroup than that in simple T2DM group(p < 0.01 or p < 0.05). Multivariate logistic regression analysis showed that levels of 25-(OH) D were negative correlation with risk of NAFLD and progressive liver fibrosis(p = 0.011、p = 0.044,respectively).

CONCLUSIONS

we could come to a conclusion that low levels of 25-(OH) D was a risk factor for NAFLD and progressive liver fibrosis in T2DM patients.

Efficacy of vitamin D supplement in children with nonalcoholic fatty liver disease: A protocol for systematic review and meta-analysis

BACKGROUND

The number of children with nonalcoholic fatty liver disease (NAFLD) is proliferating. However, currently, there are no drugs approved for the management of NAFLD. There have been some studies on vitamin D and NAFLD in children. However, the effectiveness of vitamin D in children with NAFLD has not been systematically evaluated. The objective of this systematic review will be to evaluate the effectiveness of vitamin D in children with NAFLD.

METHODS

We will search through PubMed, Google Scholar, Cochrane Library, Web of Science, and the ClinicalTrials.gov website without restriction on publishing status. To supplement our search strategy, we will scan the reference lists of the identified studies for detailed evaluation for additional possible eligible studies, and we will also search conference proceedings related to this topic. All databases were searched from inception to present. Any clinical randomized controlled trials related to vitamin D supplement for treating NAFLD (simple steatosis/NAFL and NASH) in children will be included. NAFLD had to be diagnosed by liver histology, imaging (ultrasound, computer tomography, magnetic resonance imaging). The primary outcomes will be changes in liver fibrosis and liver enzymes. The variations in serum vitamin D level, BMI, insulin levels, lipid profiles, liver fat content will also be assessed. All statistical analyses will be carried out using RevMan, version 5.3, Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014.

RESULTS

This study will provide a comprehensive high-quality synthesis to evaluate the effectiveness of vitamin D supplementation in children with NAFLD.

CONCLUSION

This systematic review and meta-analysis will provide evidence to judge whether vitamin D supplementation is an effective intervention for children with NAFLD.

REGISTRATION NUMBER

INPLASY202050049.

Serum 25-hydroxyvitamin-D and nonalcoholic fatty liver disease: Does race/ethnicity matter? Findings from the MESA cohort

BACKGROUND AND AIMS

Low serum 25-hydroxyvitamin D (25(OH)D) is associated with higher nonalcoholic fatty liver disease (NAFLD) risk in studies of mainly white participants. Significant racial/ethnic differences exist in serum 25(OH)D and NAFLD prevalence questioning extending this association to other racial/ethnic groups. We tested whether the association between serum 25(OH)D and NAFLD vary by race/ethnicity.

METHODS AND RESULTS

This was a cross-sectional analysis from the Multi-Ethnic Study of Atherosclerosis (MESA) that included 3484 participants (44% male; 38.4% Whites, 27.8% African-Americans, 23.5% Hispanics, and 10.3% Chinese-Americans) who had serum 25(OH)D and upper abdominal CT images available at baseline. Serum 25(OH)D was measured by high-performance liquid chromatography-tandem mass spectrometry. NAFLD was identified if liver-to-spleen Hounsfield-Unit ratio was <1. Whites had the highest 25(OH)D level and African-Americans had the lowest level (mean ± SD: 29.5 ± 10.4 vs.19.9 ± 9.1, respectively). Six hundred and eleven (17.5%) participants had NAFLD; Hispanics had the highest prevalence (26.2%) followed by Chinese-Americans (19.8%), Whites (15.8%) and African-Americans (11.7%), P < 0.0001. In adjusted model, the association of 25(OH)D with NAFLD differed by race/ethnicity (P < 0.0001). Negative association was only evident in Causations (OR (95% CI):1.23 (1.03, 1.47) per 1 SD lower serum 25(OH)D). For other racial/ethnic groups, BMI, triglycerides, diabetic status and/or smoking, but not serum 25(OH)D, were common independent risk factors for NAFLD.

CONCLUSIONS

The negative association between serum 25(OH)D and NAFLD in Whites may not be broadly generalizable to other racial/ethnic groups. Modifiable risk factors including BMI, triglycerides, diabetic status and/or smoking associate with NAFLD risk in non-white racial/ethnic groups beyond 25(OH)D.

The Level of Vitamin D in Children and Adolescents with Nonalcoholic Fatty Liver Disease: A Meta-Analysis

Background

The relationship between vitamin D level and NAFLD has not been investigated in children and adolescents. We performed a meta-analysis of published observational studies to assess this association between vitamin D levels (measured as serum 25-hydroxy vitamin D [25(OH)D]) and NAFLD in this age group.

Methods

Relevant studies conducted before May 20, 2018, were identified from the following electronic databases: PubMed, the Cochrane Library, Embase, and the Chinese CNKI databases. The quality of the included studies was evaluated using the Newcastle Ottawa Scale, and associations between vitamin D levels and NAFLD were estimated using standardised mean differences (SMD) and 95% confidence interval (CI). Subgroup and sensitivity analysis were used to identify sources of heterogeneity, and publication bias was evaluated using funnel plots.

Results

Eight articles were included in this meta-analysis. A significant difference was observed between low 25(OH)D levels and NAFLD in children and adolescents (SMD = -0.59, 95%CI = -0.98, -0.20, P <  0.01). Subgroup analysis revealed no differences in the study type, geographic location, BMI, and age subgroups.

Conclusions

Low vitamin D levels were associated with NAFLD in children and adolescents.

Association between Vitamin D Levels and Nonalcoholic Fatty Liver Disease: Potential Confounding Variables

Nonalcoholic fatty liver disease (NAFLD), historically considered to be the hepatic component of the metabolic syndrome, is a spectrum of fat-associated liver conditions, in the absence of secondary causes, that may progress to nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. Disease progression is closely associated with body weight or fatness, dyslipidemia, insulin resistance, oxidative stress, and inflammation. Recently, vitamin D deficiency has been linked to the pathogenesis and severity of NAFLD because of vitamin D "pleiotropic" functions, with roles in immune modulation, cell differentiation and proliferation, and regulation of inflammation. Indeed, several studies have reported an association between vitamin D and NAFLD/NASH. However, other studies have failed to find an association. Therefore, we sought to critically review the current evidence on the association between vitamin D deficiency and NAFLD/NASH, and to analyze and discuss some key variables that may interfere with this evaluation, such as host-, environment-, and heritability-related factors regulating vitamin D synthesis and metabolism; definitions of deficient or optimal vitamin D status with respect to skeletal and nonskeletal outcomes including NAFLD/NASH; methods of measuring 25(OH)D; and methods of diagnosing NAFLD as well as quantifying adiposity, the cardinal link between vitamin D deficiency and NAFLD.

The association of serum FGF23 and non-alcoholic fatty liver disease is independent of vitamin D in type 2 diabetes patients

Recent studies have shown that circulating fibroblast growth factor (FGF) 23 and vitamin D levels are closely correlated with insulin resistance. The aim of this study was to investigate the relationship among serum FGF 23 levels, serum 25-hydroxyvitamin D [25(OH)D] levels, and non-alcoholic fatty liver disease (NAFLD) in Chinese patients with type 2 diabetes mellitus (T2DM). This study enrolled 331 hospitalized T2DM patients (209 patients with NAFLD and 122 patients without NAFLD). Serum FGF23 levels were measured using a sandwich enzyme-linked immunosorbent assay. Serum 25(OH)D levels were determined by an electrochemiluminescence immunoassay. NAFLD was diagnosed by hepatic ultrasound, and the fatty liver index (FLI) was calculated to quantify hepatic steatosis. Results showed that T2DM patients with NAFLD had significantly higher serum FGF23 levels (44.17 [37.92-51.30] pg/mL vs 40.21 [34.07-48.33] pg/mL, P = .002), but lower serum 25(OH)D levels (16.43 [12.70-21.37] ng/mL vs 19.59 [13.78-26.26] ng/mL, P = .002) than those without NAFLD. Moreover, the incidence rate of NAFLD increased with increasing serum FGF23 levels and decreased with increasing 25(OH)D levels (both P < .05). Logistic regression analysis showed that both serum FGF23 and 25(OH)D levels were independent factors for NAFLD (both P < .05). Furthermore, a multiple stepwise regression analysis also revealed that both serum FGF23 and 25(OH)D levels were independently correlated with FLI (both P < .01). In conclusion, both high FGF23 and low vitamin D levels showed an independent relationship with NAFLD in Chinese T2DM patients, indicating that FGF23 and vitamin D function via different regulatory pathways in the liver.

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.

Is Vitamin D an Independent Risk Factor of Nonalcoholic Fatty Liver Disease?: a Cross-Sectional Study of the Healthy Population

The association between vitamin D levels and nonalcoholic fatty liver disease (NAFLD) has been recognized. However, few studies showed independent associations between vitamin D deficiency and NAFLD after a sex-related adjustment for metabolic factors. We aimed to study whether vitamin D deficiency is an independent risk factor of NAFLD even after controlling for metabolic syndrome and visceral fat in both sexes. In this cross-sectional study, 7,514 Korean adults (5,278 men, 2,236 women) participated in a health check-up program. They underwent blood tests, abdominal computed tomography (CT) of the visceral fat area, and ultrasonography for NAFLD screening. Multiple logistic regression analysis was used to investigate the association of vitamin D deficiency with NAFLD according to the sex differences. Vitamin D deficiency is associated with NAFLD. The adjusted odds ratio (aOR) for NAFLD increased sequentially with decreasing vitamin D level, even after adjusting for metabolic syndrome and visceral fat. The subjects in the vitamin D sufficiency group (20-30 ng/mL) had an aOR for NAFLD of 1.18 (95% CI, 1.00-1.39), whereas the deficiency group (< 20 ng/mL) had an aOR of 1.29 (95% CI, 1.10-1.52). However, we have detected a significant sex-related interaction when analyzing the results. A significant relationship between vitamin D deficiency and NAFLD was found in men (aOR, 1.33; 95% CI, 1.11-1.60) but not in women.

The Effect of Serum Vitamin D on Serum ALT Levels in Healthy Individuals

BACKGROUND

Several studies have examined the relationship between vitamin D (VD) and liver disease but none have explored this relationship in adults with normal liver enzymes. Our aim was to explore an independent association of VD with alanine aminotransferase (ALT) in a large sample of the US adults with liver enzymes in normal range (≤39 U/L).

METHODS

We used the continuous National Health and Nutrition Examination Survey from 2001 to 2006. We excluded individuals with serum ALT>39 U/L. We built linear regression models to estimate unadjusted and adjusted (age, sex, race, diabetes, hypertension, alcohol use, smoking, and body mass index) effect sizes, taking into account the complex probability survey design.

RESULTS

Of the 12,155 participants, 6635 (54.6%) were women, mean±SD age was 49.9±19.4 years, VD was 21.9±9.2 ng/mL, and ALT was 20.9±6.9 U/L. In unadjusted analysis, VD was significantly associated with serum ALT (0.02 U/L/ng/mL of VD, P=0.007). After adjustment for confounders, VD remained statistically significantly associated with serum ALT levels (0.04 U/L, P<0.001). Similarly, individuals in the highest quartile of VD had significantly higher serum levels of ALT than those in the lowest quartile (unadjusted difference=0.98 U/L, P<0.001; adjusted difference=1.21 U/L, P<0.001).

CONCLUSIONS

We found a positive association between VD and ALT after excluding individuals with suspected active liver injury (ALT>39 U/L). The underlying mechanisms for this association are not known and needs further study.

Low vitamin D levels and non-alcoholic fatty liver disease, evidence for their independent association in men in East China: a cross-sectional study (Survey on Prevalence in East China for Metabolic Diseases and Risk Factors (SPECT-China))

Recent studies have suggested an association between vitamin D and non-alcoholic fatty liver disease (NAFLD); however, some results are subject to debate. This study was carried out to evaluate the correlation between NAFLD and vitamin D in men and women in East China. The data were obtained from a cross-sectional study that focused on the health and metabolic status of adults in sixteen areas of East China. According to ultrasonic assessments, the patients were divided into normal and NAFLD groups. Demographic characteristics and biochemical measurements were obtained. Binary logistic regression analysis was used to explore the association. In total, 5066 subjects were enrolled, and 2193 (43·3 %) were diagnosed with NAFLD; 84·56 % of the subjects showed vitamin D deficiency. Subjects with high vitamin D levels had a lower prevalence of NAFLD, particularly male subjects. Within the highest quartile of vitamin D levels, the prevalence of NAFLD was 40·8 %, whereas the lowest quartile of vitamin D levels showed a prevalence of 62·2 %, which was unchanged in women across the vitamin D levels. Binary logistic analysis showed that decreased vitamin D levels were associated with an increased risk of NAFLD (OR 1·54; 95 % CI 1·26, 1·88). This study suggests that vitamin D levels are significantly associated with NAFLD and that vitamin D acts as an independent factor for NAFLD prevalence, particularly in males in East China. Vitamin D interventional treatment might be a new target for controlling NAFLD; elucidating the mechanism requires further research.