Role of vitamin D in children with hepatosteatosis

The Association between Vitamin D Deficiency and Hepatosteatosis in Children and Adolescents with Obesity

INTRODUCTION

Increasingly, research groups have been studying the association of serum vitamin D and metabolic health indicators, especially in patients with obesity. We compared the serum 25-hydroxyvitamin D (25(OH)D) concentrations in children and adolescents who had obesity and hepatosteatosis with children and adolescents who had obesity without hepatosteatosis and investigated the relationship between serum 25(OH)D concentrations and severity of hepatosteatosis. We also aimed to assess the effect of vitamin D treatment after 6 months on hepatosteatosis and liver biochemistry.

METHODS

One hundred thirty-three patients with obesity (body mass index [BMI] >+2 standard deviations [SDs] for their age and gender) and vitamin D deficiency (serum 25(OH)D <12 ng/mL) were recruited. Anthropometric measurements, biochemical parameters (serum calcium, phosphate, alkaline phosphatase, parathyroid hormone, 25(OH)D, glucose and insulin concentrations), and ultrasonographic findings of hepatosteatosis were recorded before and 6 months after Vitamin D treatment. χ2, Student's t tests, and multivariate analysis were performed.

RESULTS

Grade 1, 2, and 3 hepatosteatosis at baseline was present in 51 (38.4%), 43 (32.3%), and 10 (7.5%) subjects, respectively. Mean (± SD) serum 25(OH)D concentrations were significantly lower in those with hepatosteatosis (8.4 ± 2.4 ng/mL) compared with those without hepatosteatosis (9.9 ± 2.4 ng/mL, p < 0.005). Multivariable logistic regression analysis showed serum 25(OH)D concentration was the independent predictor for hepatosteatosis (p < 0.005), whereas age, sex, weight SD, BMI SD, and homeostasis model of assessment (HOMA)-insulin resistance (IR) were not (p > 0.05). There was no significant difference in BMI SD, HOMA-IR, and liver enzymes between subjects with and without hepatosteatosis (p > 0.05). Despite improvement in serum 25(OH)D concentrations at 6 months post-treatment (34.7 ± 10.6 ng/mL vs. 8.7 ± 2.4 ng/mL; p < 0.0001), there was no significant difference in the proportion of patients with different severity of hepatosteatosis as compared to before treatment (p = 0.88).

CONCLUSION

Serum 25(OH)D concentrations were lower in children and adolescents with obesity and hepatic steatosis as compared to those without hepatic steatosis, with an inverse association between the severity of hepatosteatosis and serum 25(OH)D concentrations. Vitamin D treatment in children and adolescents with obesity and hypovitaminosis D did not improve severity of hepatic steatosis on ultrasonography at 6 months.

High parathyroid hormone level as a marker of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis: A systematic review and meta-analysis

BACKGROUND AND AIMS

Studies have suggested that high parathyroid hormone (PTH) was associated with non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH), although the results from existing studies are inconsistent. Using systematic review and meta-analysis, we aimed to determine the association of PTH with NAFLD and NASH.

METHODS

Potentially eligible studies were identified from Embase and Medline databases from using search strategy consisting of terms for "NAFLD/NASH", and "PTH". Eligible study must consist of one group of patients with NAFLD/NASH and another group without NAFLD/NASH. The study must provide mean ± SD PTH in both groups. We extracted such data to calculate mean difference (MD). Pooled MD was then calculated by combining MDs of each study using random-effects model. Funnel plot was used to assess for the presence of publication bias.

RESULTS

A total of 388 articles were identified. After systematic review, 12 studies fulfilled the eligibility criteria and were included into the meta-analysis. The meta-analysis of 10 studies revealed the significant association between high PTH and NAFLD, with the pooled MD of 5.479 (95%CI 0.947-10.011, I2 82.4%). The funnel plot was symmetric and did not suggest publication bias. The meta-analysis of 4 studies revealed the non-significant association between high PTH and NASH, with the pooled MD of 11.955 (95%CI -4.703 - 28.614, I2 81.0%).

CONCLUSIONS

High PTH level is significantly associated with NAFLD and can be used as a marker of NAFLD. However, high PTH level is non-significantly associated with NASH. Further studies are needed to increase the sample size and eliminate the confounding factors.

Vitamin D level, body mass index and fracture risk in children: vitamin D deficiency and fracture risk

The objective of this study was to determine the impacts of preventable causes of fracture, such as vitamin D deficiency, disturbed calcium homeostasis and obesity on fracture occurrence in minor traumas. In this way, the effects of relevant parameters on fracture may be further elucidated. A prospective case-control study in children aged 2-18 years children with and without fractures was performed. Participants with a pediatric trauma score higher than 10 presenting to minor trauma were included to exclude the significant impact of severe trauma on fracture. The effects of obesity, parameters associated with vitamin D and Ca homeostasis on fracture occurrence were evaluated. Univariate and multivariate analyses were used to test for associations between fracture status and the assessed variables. The relationships between the variables and the odds of fracture occurrence were examined using logistic regression models. The sample consisted of 76 patients and 50 controls. There were no significant differences between the patients and controls in terms of age, sex, trauma type and pubertal period. The patients had a significantly higher mean BMI percentile (61.2 ± 30.7, 36.7 ± 30.7; P < 0.001). Likewise, patients were more likely than controls to have a lower mean 25(OH)D level and mean phosphorus level (respectively, 13.4 ± 7.0, 17.3 ± 7.8; P = 0.004, and 4.6 ± 0.7, 5.1 ± 0.8; P < 0.001). Moreover, fractures were substantially more frequent in children with vitamin D deficiency (<20 ng/mL, χ2: 7.781, df: 1, P = 0.005). In the multivariate logistic model, BMI percentile and vitamin D levels remained significantly associated with increased odds of fracture [1.02 (1.01-1.04), P < 0.001 and 0.93 (0.89-0.98), P = 0.01]. The present study supports an association of high BMI and vitamin D deficiency with an increased odds of fracture occurrence in children. The findings may help physicians to reduce the risk factors of fracture by preventive efforts. Thus, unexpected health costs and morbidity may be minimized.

Τhe anthropometric and biochemical profile of pediatric non-alcoholic fatty liver disease: A systematic review and a meta-analysis

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in children and one of the leading indications for liver transplantation in adults. However, current screening methods are inadequate and are accompanied by several disadvantages. This meta-analysis aims to identify the anthropometrical and biochemical characteristics most commonly appearing in pediatric NAFLD that could contribute to the diagnosis of the disease in the every-day clinical setting.

METHODS

A systematic search was conducted in major electronic databases (MEDLINE, Scopus and Embase) up to 15th of August 2021. Primary outcome was the comparison of the anthropometric characteristics, whereas secondary outcomes were the comparisons of biochemical profile, lipid profile, and metabolic parameters in children with NAFLD compared with age-matched healthy controls. Quality assessment was performed with Newcastle-Ottawa Scale (NOS) and results were expressed as mean differences with 95% confidence intervals.

RESULTS

Sixty-four studies were included. Two different comparisons were designed regarding the body mass status. Statistically significant differences were demonstrated by comparing children with NAFLD vs lean/normal weighted controls in body weight (23.0 kg, 95% CI: 14.0-31.8, P < 0.00001), height (3.07 cm, 95% CI: 0.21-5.94, P = 0.04), ΒΜΙ (10 kg/m², 95% CI: 8.36-11.7, P < 0.00001) and waist circumference 25.8 cm (95% CI: 20.6-30.9, P < 0.00001) and by comparing children with NAFLD vs overweight/obese controls in weight (6.81 kg, 95% CI: 3.81-9.81), height (3.18 cm, 95% CI: 1.24 to 5.13, P = 0.001), BMI (2.19 kg/m², 95% CI: 1.76-2.62, P < 0.00001) and WC (7.35 cm, 95% CI: 6.20-8.49, P < 0.00001).

CONCLUSIONS

Anthropometrical and biochemical characteristics of children and adolescents with NAFLD are statistically significantly different compared to age-matched controls; these characteristics could be used to identify individuals at risk of developing NAFLD and related comorbidities.

Relationship of Vitamin D Deficiency and Fatty Liver in Children as Defined by Multiple Imaging and Histologic Endpoints

Objectives

The relationship between vitamin D deficiency (VDD) and pediatric nonalcoholic fatty liver disease (NAFLD) remains uncertain due to conflicting results and few studies with histologic endpoints. We therefore used multiple imaging and histologic NAFLD endpoints to more comprehensively assess the association between VDD and NAFLD in a large pediatric population.

Methods

Data were obtained from an ongoing pediatric NAFLD study in Bronx, NY. Briefly, overweight and obese children aged 2-18 years with alanine aminotransferase (ALT) levels ≥ 35 U/L were serially enrolled. Liver biopsy was obtained in accordance with clinical guidelines. All participants had liver imaging, namely, controlled attenuation parameter (CAP; Echosens, France) to assess steatosis and, to assess fibrosis, vibration controlled transient elastography (VCTE; FibroScan™, Echosens, France) and acoustic radiation force impulse (ARFI; Philips, Netherlands) imaging. Levels of 25-hydroxyvitamin D were measured serologically.

Results

N=276 (88%) of 315 participants had 25-OH vitamin D results, of whom 241 (87%) were Hispanic, 199 (72%) were male, and 92 (33%) underwent liver biopsy. VDD was univariately associated with high waist circumference (p=0.004), high-density lipoprotein level (p=0.01), season (p=0.009), and CAP score (p=0.01). In multivariate analysis, only waist circumference (p=0.0002) and biopsy inflammation grade (p=0.03) were associated with VDD, though the latter had not approximated statistical significance in univariate analysis (p=0.56). There was no association between VDD and hepatic steatosis, ballooning, NAFLD Activity Score, ARFI or VCTE elasticity scores.

Conclusions

VDD was not associated with NAFLD defined by imaging and histologic endpoints, except for a possible relation with histologic inflammation grade.

Cardiovascular Risk Factors in Children with Obesity, Preventive Diagnostics and Possible Interventions

The increasing burden of obesity plays an essential role in increased cardiovascular morbidity and mortality. The effects of obesity on the cardiovascular system have also been demonstrated in childhood, where prevention is even more important. Obesity is associated with hormonal changes and vascular dysfunction, which eventually lead to hypertension, hyperinsulinemia, chronic kidney disease, dyslipidemia and cardiac dysfunction—all associated with increased cardiovascular risk, leading to potential cardiovascular events in early adulthood. Several preventive strategies are being implemented to reduce the cardiovascular burden in children. This paper presents a comprehensive review of obesity-associated cardiovascular morbidity with the preventive diagnostic workup at our hospital and possible interventions in children.

Vitamin D Effect on Ultrasonography and Laboratory Indices and Biochemical Indicators in the Blood: an Interventional Study on 12 to 18-Year-Old Children with Fatty Liver

PURPOSE

The rising prevalence of childhood obesity in the past decades has caused non-alcoholic fatty liver disease (NAFLD) to become the most common cause of pediatric chronic liver disease worldwide. This study was aimed at determining the effect of vitamin D (Vit D) on ultrasonography and laboratory indices of NAFLD and some blood biochemical indicators in children.

METHODS

In this interventional study liver ultrasonography was performed in 200 children with overweight and obesity. A 108 had fatty liver among which 101 were randomly divided into two groups of study (n=51) and control (n=50). The study group was treated with Vit D, 50000 U once a week whereas the control group received placebo with the same dose and package, both for 12 weeks. At the end of the intervention lab tests and ultrasound study was performed once again to evaluate the response to treatment.

RESULTS

It was found out that Vit D supplementation improved the fatty liver grade in the study group. The mean changes in hemoglobin (Hb), uric acid, highdensity lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), insulin, albumin and alanine aminotransferase (ALT) was significantly higher in the study group compared to controls (p<0.05). After the intervention and means adjustment, a significant difference was obtained in HDL-C, insulin, LDL-C and homeostasis model assessment of insulin resistance (HOMA-IR) between the two groups.

CONCLUSION

Vit D supplementation in addition to improving the fatty liver grade in ultrasonography and increasing the blood Vit D level, increases the HDL and Hb level besides decreasing uric acid, LDL, HOMA-IR, insulin and ALT levels.

The association of lipid metabolism and non-alcoholic fatty liver disease in children with obesity

Aim:

Obesity, insulin resistance, and hyperlipidemia have been shown as risk factors for non-alcoholic fatty liver disease. In this study, the association between lipid and lipoprotein metabolism abnormalities and the presence of non-alcoholic fatty liver disease was investigated in patients with obesity.

Material and Methods:

In this study, the clinical, laboratory and imaging findings of 357 children and adolescent patients (199 girls and 158 boys) aged 2–18 years who were diagnosed as having obesity between 2013 and 2018 were retrospectively analyzed. The clinical and laboratory features of the patients who were diagnosed as having non-alcoholic fatty liver disease using ultrasonography were compared with patients who did not have non-alcoholic fatty liver disease. All lipid and lipoprotein levels were defined as hypo-, normo- and hyperlipidemic in comparison with the reference values according to age and sex.

Results:

The frequency of non-alcoholic fatty liver disease was 44.5% in the entire study group and was higher in males (p<0.05). The body weight, body mass index, alanine aminotransferase, glucose, insulin, non-high-density lipoprotein-cholesterol, and HOMA-IR scores were found to be higher in the patients with non-alcoholic fatty liver disease, whereas the high-density lipoprotein-cholesterol level was lower (p<0.05). There was no difference in the frequency of non-alcoholic fatty liver disease among the patients with low, normal, and high total cholesterol, triglyceride and low-density lipoprotein-cholesterol levels (p>0.05). The frequency of lipid metabolism disorder (hypolipidemia and/or hyperlipidemia) was found as 77.5% in all patients.

Conclusion:

Non-alcoholic liver disease and lipid metabolism disorders are common in children and adolescents with obesity. The frequency of non-alcoholic fatty liver disease in hypolipidemic, normolipidemic, and hyperlipidemic patients was not different. This finding indicated that the increase in the amount of body fatty tissue and insulin resistance were more important risk factors in the development of non-alcoholic fatty liver disease.

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.

The relationship between vitamin D level and hepatosteatosis in obese children

OBJECTIVE:

The increasing incidence of obesity in children is a significant risk factor for nonalcoholic fatty liver disease and obesity-associated morbidity. In the present study, we aimed to explore the correlation between Vitamin D level and hepatosteatosis in obese children.

METHODS:

A total of 110 children aged 10–16 years who presented to pediatric endocrinology outpatient clinic for obesity were enrolled. The study was completed in a single season between September and November. Hepatosteatosis was diagnosed by ultrasonography. The patients were grouped into two groups: Group 1 comprised patients with hepatosteatosis and Group 2 consisted of patients without hepatosteatosis. 25 hydroxy (25-OH) Vitamin D levels were compared between patients with and without hepatosteatosis.

RESULTS:

No statistically significant difference was observed between 25-OH Vitamin D levels of patients with and without hepatosteatosis. When the effects of age and sex were kept constant, there was no significant correlation between Vitamin D level and aspartate aminotransferase, alanine aminotransferase, and body mass index values.

CONCLUSION:

Unlike the results of the previous studies, we were unable to detect any significant difference between Vitamin D levels of obese patients with and without hepatosteatosis. We think that obesity, rather than Vitamin D status, that is, in fact, independently associated with nonalcoholic fatty liver disease. Larger studies are needed to investigate the impact of Vitamin D in children with obesity with hepatosteatosis.

Obesity and hypovitaminosis D: causality or casualty?

Epidemiological studies reported that vitamin D deficiency represents an increasingly widespread phenomenon in various populations. Vitamin D deficiency is considered a clinical syndrome determined by low circulating levels of 25-hydroxyvitamin D (25(OH)D), which is the biologically-inactive intermediate and represents the predominant circulating form. Different mechanisms have been hypothesized to explain the association between hypovitaminosis D and obesity, including lower dietary intake of vitamin D, lesser skin exposure to sunlight, due to less outdoor physical activity, decreased intestinal absorption, impaired hydroxylation in adipose tissue and 25(OH)D accumulation in fat. However, several studies speculated that vitamin D deficiency itself could cause obesity or prevent weight loss. The fat-solubility of vitamin D leads to the hypothesis that a sequestration process occurs in body fat depots, resulting in a lower bioavailability in the obese state. After investigating the clinical aspects of vitamin D deficiency and the proposed mechanisms for low 25(OH)D in obesity, in this manuscript we discuss the possible role of vitamin D replacement treatment, with different formulations, to restore normal levels in individuals affected by obesity, and evaluate potential positive effects on obesity itself and its metabolic consequences. Food-based prevention strategies for enhancement of vitamin D status and, therefore, lowering skeletal and extra-skeletal diseases risk have been widely proposed in the past decades; however pharmacological supplementation, namely cholecalciferol and calcifediol, is required in the treatment of vitamin D insufficiency and its comorbidities. In individuals affected by obesity, high doses of vitamin D are required to normalize serum vitamin D levels, but the different liposolubility of different supplements should be taken into account. Although the results are inconsistent, some studies reported that vitamin D supplementation may have some beneficial effects in people with obesity.

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.

Low 25-hydroxyvitamin D level is not an independent risk factor for hepatosteatosis in obese children

BACKGROUND

Obesity is an important risk factor for non-alcoholic fatty liver disease. Few studies have evaluated the association between vitamin D and non-alcoholic fatty liver disease in obese children. Therefore, we conducted a study to examine the relationship of vitamin D levels and hepatosteatosis in obese children.

METHODS

One hundred and eleven children with obesity participated in this study. Hepatosteatosis was diagnosed and graded using ultrasonography in all patients. Study participants were divided based on the presence of hepatosteatosis into two subgroups (hepatosteatosis and non-hepatosteatosis). Serum levels of 25-hydroxyvitamin D, calcium, phosphate, alkaline phosphatase, parathormone, and lipids were measured and compared.

RESULTS

Hepatosteatosis existed in 52% of obese children without chronic diseases. There was no statistically significant difference in the vitamin D level between the hepatosteatosis and non-hepatosteatosis groups. Alanine aminotransferase levels and the triglycerides-to-high density lipoprotein ratio were significantly higher, and the high density lipoprotein levels were significantly lower in the hepatosteatosis group compared to the non-hepatosteatosis group.

CONCLUSIONS

Vitamin D deficiency is not directly related with hepatosteatosis. A high ALT level and a high triglycerides-to-HDL ratio and low HDL levels are more significant in hepatic steatosis in obese children.