Prevalence of non-alcoholic fatty liver disease in children and relationship to metabolic syndrome, insulin resistance, and waist circumference

Nonalcoholic fatty liver disease and insulin resistance in children

Nonalcoholic fatty liver disease (NAFLD), a spectrum of liver diseases characterized by excessive fat accumulation, is the leading cause of chronic liver disease. The global prevalence of NAFLD is increasing in both adults and children. In Korea, the prevalence of pediatric NAFLD increased from 8.2% in 2009 to 12.1% in 2018 according to a national surveillance study. For early screening of pediatric NAFLD, laboratory tests including aspartate aminotransferase and alanine aminotransferase; biomarkers including hepatic steatosis index, triglyceride glucose index, and fibrosis-4 index; and imaging studies including ultrasonography and magnetic resonance imaging are required. Insulin resistance plays a major role in the pathogenesis of NAFLD, which promotes insulin resistance. Thus, the association between NAFLD and insulin resistance, diabetes mellitus, and metabolic syndrome has been reported in many studies. This review addresses issues related to the epidemiology and investigation of NAFLD as well as the association between NAFLD and insulin resistance and metabolic syndrome with focus on pediatric NAFLD.

Parental metabolic syndrome and elevated liver transaminases are risk factors for offspring, even in children and adolescents with a normal body mass index

Introduction

The parent-child correlation in metabolic syndrome (MetS) and elevated transaminases is sparsely researched. We assessed the correlation of parental MetS and elevated transaminase status with these conditions in their children.

Methods

Data of 4,167 youths aged 10-18 years were analyzed in a population-based survey, and the parental characteristics were stratified by the presence or absence of MetS or alanine aminotransferase (ALT) elevation in their children. The prevalence of these conditions in children was analyzed according to their parents' status. Logistic regression analyses were performed with MetS and ALT elevation in youth as the dependent variables.

Results

The proportions of MetS and ALT elevation were higher in parents of children with MetS and ALT elevation than in those without, even among youths without obesity. In logistic regression analyses, age, body mass index-standard deviation score (BMI-SDS), and ALT elevation were positively associated with MetS, whereas age, male sex, BMI-SDS, protein intake, and MetS were positively associated with ALT elevation. Higher protein intake was related to ALT elevation, whereas metabolic components and nutritional factors were closely related in parents and their children. Odds ratios (OR) of ALT elevation for MetS was 8.96 even after adjusting nutritional factors in the children. The OR was higher for ALT elevation in the children of parents with MetS and ALT elevation compared to those without. ORs for MetS and ALT elevation in the children of parents with MetS were higher than those of children of parents without MetS, even after adjusting for nutritional intake. ORs for ALT elevation were higher in the children of parents with ALT elevation than those without, even after adjusting for nutritional intake and BMI of parents as well as the nutritional intake, age, sex, and BMI-SDS of the children.

Conclusion

MetS and elevated liver transaminase statuses in children were associated with those of their parents even after adjusting for nutritional factors, and the relationships were more prominent in the youth without obesity.

Skeptical Look at the Clinical Implication of Metabolic Syndrome in Childhood Obesity

Metabolic syndrome (MetS) is defined by a cluster of several cardio-metabolic risk factors, specifically visceral obesity, hypertension, dyslipidemia, and impaired glucose metabolism, which together increase risks of developing future cardiovascular disease (CVD) and type 2 diabetes mellitus (T2D). This article is a narrative review of the literature and a summary of the main observations, conclusions, and perspectives raised in the literature and the study projects of the Working Group of Childhood Obesity (WGChO) of the Italian Society of Paediatric Endocrinology and Diabetology (ISPED) on MetS in childhood obesity. Although there is an agreement on the distinctive features of MetS, no international diagnostic criteria in a pediatric population exist. Moreover, to date, the prevalence of MetS in childhood is not certain and thus the true value of diagnosis of MetS in youth as well as its clinical implications, is unclear. The aim of this narrative review is to summarize the pathogenesis and current role of MetS in children and adolescents with particular reference to applicability in clinical practice in childhood obesity.

American Indian Alaska Native (AIAN) adolescents and obesity: the influence of social determinants of health, mental health, and substance use

OBJECTIVE

To explore the prevalence of obesity among American Indian and Alaska Native (AIAN) adolescents aged 12-19 years in association with social determinants of health (SDOH), and mental health and substance use disorders.

METHODS

Guided by the World Health Organization's Social Determinants of Health Framework, we examined data from the Indian Health Service (IHS) Improving Health Care Delivery Data Project from Fiscal Year 2013, supplemented by county-level data from the U.S. Census and USDA. Our sample included 26,226 AIAN adolescents ages 12-19 years. We described obesity prevalence in relationship to SDOH and adolescents' mental health and substance use disorder status. We then fit a multivariable logit generalized linear mixed model to estimate the relationships after adjusting for other individual and county level characteristics.

RESULTS

We observed a prevalence of 32.5% for obesity, 13.8% for mental health disorders, and 5.5% for substance use disorders. Females had lower odds of obesity than males (OR = 0.76, p < 0.001), which decreased with age. Having Medicaid coverage (OR = 1.09, p < 0.01), residing in a county with lower education attainment (OR = 1.17, p < 0.05), and residing in a county with higher rates of poverty (OR = 1.51, p < 0.001) were each associated with higher odds of obesity. Residing in a county with high access to a grocery store (OR = 0.73, p < 0.001) and residing in a county with a higher proportion of AIANs (OR = 0.83, p < 0.01) were each associated with lower odds of obesity. Those with mental health disorders had higher odds of obesity (OR = 1.26, p < 0.001); substance use disorders were associated with decreased odds of obesity (OR = 0.73, p < 0.001).

CONCLUSIONS

Our findings inform future obesity prevention and treatment programs among AIAN youth; in particular, the need to consider mental health, substance use, and SDOH.

Prevalence of non-alcoholic fatty liver disease in overweight and obese children seeking ambulatory healthcare in Nairobi, Kenya

BACKGROUND

While linked to obesity and associated with an increased cardiovascular morbidity, non-alcoholic fatty liver disease (NAFLD) is an often-asymptomatic cause of chronic liver disease in children. Early detection provides opportunity for interventions to curb progression. Childhood obesity is on the rise in low/middle-income countries, but cause-specific mortality data associated with liver disease are scanty. Establishing the prevalence of NAFLD in overweight and obese Kenyan children would guide in public health policies aimed at early screening and intervention.

OBJECTIVES

To investigate prevalence of NAFLD in overweight and obese children aged 6-18 years using liver ultrasonography.

METHODOLOGY

This was a cross-sectional survey. After obtaining informed consent, a questionnaire was administered, and blood pressure (BP) measured. Liver ultrasonography was performed to assess fatty changes. Categorical variables were analysed using frequency and percentages. χ² test and multiple logistic regression model were used to determine relationship between exposure and outcome variables.

RESULTS

Prevalence of NAFLD was 26.2% (27/103, 95% CI=18.0% to 35.8%). There was no association between sex and NAFLD (OR1.13, p=0.82; 95% CI=0.4 to 3.2). Obese children were four times more likely to have NAFLD compared with overweight children (OR=4.52, p=0.02; 95% CI=1.4 to 19.0). About 40.8% (n=41) had elevated BP, but there was no association with NAFLD (OR=2.06; p=0.27; 95% CI=0.6 to 7.6). Older children (13-18 years) were more likely to have NAFLD (OR 4.42; p=0.03; 95% CI=1.2 to 17.9).

CONCLUSION

Prevalence of NAFLD was high in overweight and obese school children in Nairobi. Further studies are needed to identify modifiable risk factors to arrest progression and prevent sequelae.

Macronutrient composition and its effect on body composition changes during weight loss therapy in patients with non-alcoholic fatty liver disease: Secondary analysis of a randomized controlled trial

OBJECTIVES

Dietary composition may affect body composition during weight loss therapy. We tested the hypothesis of whether dietary macronutrient composition influences the reduction of total abdominal adipose tissue, subcutaneous adipose tissue (SAT), or visceral adipose tissue (VAT) during weight loss.

METHODS

Dietary macronutrient composition and body composition were analyzed as a secondary outcome of a randomized controlled trial of 62 participants with non-alcoholic fatty liver disease. Patients were randomly assigned to a calorie-restricted intermittent fasting (5:2), calorie-restricted low-carbohydrate high-fat (LCHF), or healthy lifestyle advice (standard-of-care) diet in a 12-wk intervention phase. Dietary intake was assessed by self-reported 3-d food diaries and by characterization of total plasma fatty acid profile. Percentage of energy intake (E%) from different macronutrients was calculated. Body composition was assessed by magnetic resonance imaging and anthropometric measurements.

RESULTS

The macronutrient composition differed significantly between the 5:2 (fat 36 E% and carbohydrates 43 E%) and the LCHF (fat 69 E% and carbohydrates 9 E%) groups (P < 0.001). Weight loss was similar in the 5:2 and LCHF groups (-7.2 [SD = 3.4] kg versus 8.0 [SD = 4.8] kg; P = 0.44) and significantly larger than for standard of care (-2.5 kg [SD = 2.3]; P < 0.001). The volume of total abdominal fat, adjusted for height, decreased on average by 4.7% (standard of care), 14.3% (5:2), and 17.7% (LCHF), with no significant differences between the 5:2 and LHCF groups (P = 0.32). VAT and SAT, adjusted for height, decreased on average by 17.1% and 12.7% for 5:2, respectively, and by 21.2% and 17.9% for LCHF, with no significant group differences (VAT [P = 0.16] and SAT [P = 0.10]). VAT was mobilized to a greater extent than SAT in all diets.

CONCLUSIONS

The 5:2 and LCHF diets had similar effects on changes in intraabdominal fat mass and anthropometrics during weight loss. This might indicate that overall weight loss is more important than diet composition to achieve changes in total abdominal adipose tissue, VAT, or SAT. The results of the present study suggest that there is a need for further studies on the effect of diet composition on body composition changes during weight loss therapy.

Comparison of the Triglyceride Glucose Index and Modified Triglyceride Glucose Indices to Predict Nonalcoholic Fatty Liver Disease in Youths

OBJECTIVE

To assess the associations between the triglyceride glucose (TyG) index and modified TyG indices with nonalcoholic fatty liver disease (NAFLD) and evaluate their ability as predictors of NAFLD in youths.

STUDY DESIGN

We analyzed the cross-sectional data of 3728 individuals aged 10-19 years using the Korea National Health and Nutrition Examination Survey, a nationally representative survey. Logistic regression analysis was performed, and ORs and 95% CIs of tertiles 2 and 3 for each variable for predicting NAFLD were calculated and compared with those of tertile 1 as the reference. Receiver operating characteristic (ROC) curves were plotted to evaluate the ability of each variable for NAFLD prediction.

RESULTS

All TyG and modified TyG indices exhibited progressively increased ORs and 95% CIs for NAFLD across all tertiles (all P < .001). In addition, all TyG and modified TyG indices significantly predicted NAFLD through ROC curves. All modified TyG indices were superior to the TyG index for predicting NAFLD in all subjects and in males. Among females, the TyG-waist-to-height ratio was superior to the TyG index, TyG-body mass index (BMI), and TyG-waist circumference (WC), and the TyG-BMI SDS and TyG-WC were superior to the TyG index.

CONCLUSIONS

The TyG and modified TyG indices are markers for NAFLD prediction in youths, and the modified TyG indices are superior to the TyG index. Modified TyG indices have the potential to be simple and cost-effective markers in screening for NAFLD in youths.

Prevalence of non-Alcoholic Fatty Liver Disease and Associated Factors in Patients with Moderate or Severe Hemophilia: A Multicenter-Based Study

Introduction

Liver health is essential for persons with hemophilia (PWH) in order to maintain access to new therapies, such as gene therapy. Non-alcoholic fatty liver disease (NAFLD) is seldom reported in the hemophilia population. The study aimed to investigate the prevalence of NAFLD and associated factors in PWH.

Methods

Data of this cross-sectional study were obtained from a multicenter collaborative registry database.

Results

A total of 163 moderate or severe PWH with a complete data of liver examination were analyzed. There were 77 (47.2%) PWH diagnosed with NAFLD. The multivariate analysis showed that overweight/obesity was associated with NAFLD (OR, 4.31, P < .001). In comparison with hemophilia B patients, hemophilia A patients showed a weaker correlation with NAFLD, (OR, 0.30, P = .009). A total of 17 (25.8%) PWH with NAFLD had an elevated level of alanine transaminase (ALT). Both overweight/obesity and presence of inhibitor to clotting factor were independently associated with elevated ALT in PWH with NAFLD.

Conclusions

The study indicated that a high prevalence of NAFLD existed in the hemophilia population. Overweight/obesity was an independent factor for NAFLD and elevated ALT.

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.

Prevalence and predictors of non-alcoholic fatty liver disease in tertiary care hospital of Taif, Saudi Arabia: A retrospective study

Background

The prevalence of nonalcoholic fatty liver disease (NAFLD) in Saudi Arabia is predicted to exceed 30% by 2030. NAFLD leads to liver fibrosis, thus increasing morbidity and health care burden. Obesity and diabetes have been strongly associated with NAFLD in different cities in Saudi Arabia.

Objectives

Therefore, we aim to determine the prevalence rate of NAFLD and specific risk factors for NAFLD among patients of tertiary care hospital of Taif city.

Material and methods

We retrospectively analyzed the medical records of patients for two years, between Feb 2017 and Feb 2019, (n = 100) referred to the hepatology clinic at King Abdulaziz Specialist Hospital in Taif. The diagnosis of NAFLD was based on the radiology report for patients who were aged >20 years old. Other parameters including fasting blood glucose (FBG), platelets count, alanine transaminase (ALT), aspartate transaminase (AST) and total bilirubin were statistically analyzed.

Results

We found that 40% (P < 0.05) of all patients had NAFLD. The results revealed that a significantly high number of patients with NAFLD have high FBG levels (75%, P < 0.0001) and total bilirubin (P < 0.05). Meanwhile, platelet count was significantly reduced in patients with NAFLD (P < 0.05).

Conclusion

NAFLD can be a serious health problem in the Taif region. In addition, high FBG is a significant specific risk factor for NAFLD. Health care providers should pay more attention to limiting the prevalence of NAFLD and its risk factors.

Clinical characteristics and risk factors of nonalcoholic fatty liver disease in children with obesity

BACKGROUND

With the increasing number of children with obesity worldwide, nonalcoholic fatty liver disease (NAFLD) has become the most common liver disease among children. It is necessary to recognize the risk factors of NAFLD for prevention in childhood since NAFLD is asymptomatic in the early stage.

OBJECTIVES

The objective of this study was to investigate possible risk factors of NAFLD in children with obesity, providing evidence for monitoring and prevention strategies at an early stage for obese children with NAFLD.

METHODS

Data were collected from 428 children and adolescents aged 6-16 years recruited from the Children's Hospital at Nanjing Medical University from September 2015 to April 2018 and analyzed. Based on a combination of ultrasound results and alanine transaminase levels, subjects were divided into three groups: simple obesity (SOB), simple steatosis (SS), and nonalcoholic fatty hepatitis (NASH). Blood biochemical examination included glucose, insulin, uric acid, lipid profile and liver enzymes.

RESULTS

Among 428 children with obesity, 235 (54.9%) had SS and 45 (10.5%) had NASH. Body mass index, body mass index standard deviation score (BMI-SDS), waist circumference, body fat, liver enzymes, uric acid and HOMA-IR level were significantly higher in the NASH group than in the SS and SOB groups (p < 0.001). 53.3% of the SS group and 49.8% of the NASH group had metabolic syndrome, significantly more than in the SOB group (19.6%, p < 0.001). After adjustment for confounding factors, logistic regression models revealed that NASH was associated with BMI-SDS ≥ 3, gender, hyperuricemia and insulin resistance.

CONCLUSIONS

The prevalence of NASH in children with obesity is closely related to high BMI-SDS, gender, insulin resistance and hyperuricemia. These findings provide evidence that monitoring risk factors of childhood obesity can assist in developing prevention strategies for liver disease at an early stage.

Advances in the Epidemiology, Diagnosis, and Management of Pediatric Fatty Liver Disease

PURPOSE

Nonalcoholic fatty liver (NAFL) is a major contributor to pediatric liver disease. This review evaluated the current literature on prevalence, screening, diagnosis, and management of NAFL in children and explored recent advances in the field of pediatric NAFL.

METHODS

A PubMed search was performed for manuscripts describing disease burden, diagnosis, and management strategies in pediatric NAFL published within the past 15 years. Systematic reviews, clinical practice guidelines, randomized controlled trials, and cohort and case-control studies were reviewed for the purpose of this article.

FINDINGS

The prevalence of NAFL in children is increasing. It is a leading cause of liver-related morbidity and mortality in children. Screening and diagnosis of NAFL in children are a challenge. Lifestyle changes and exercise are the cornerstones of the management of NAFL.

IMPLICATIONS

Further research is needed to develop better screening and diagnostic tools for pediatric NAFL, including noninvasive diagnostics. NAFL therapeutics is another area of much-needed, ongoing research.

Caffeoylquinic Acid Derivatives of Purple Sweet Potato as Modulators of Mitochondrial Function in Mouse Primary Hepatocytes

Owing to their antioxidant properties, caffeoylquinic acid (CQA)-derivatives could potentially improve the impaired metabolism in hepatic cells, however, their effect on mitochondrial function has not been demonstrated yet. Here, we evaluated the impact of three CQA-derivatives extracted from purple sweet potato, namely 5-CQA, 3,4- and 4,5-diCQA, on mitochondrial activity in primary hepatocytes using an extracellular flux analyzer. Notably, an increase of maximal respiration and spare respiratory capacity were observed when 5-CQA and 3,4-diCQA were added to the system indicating the improved mitochondrial function. Moreover, 3,4-diCQA was shown to considerably increase glycolytic reserve which is a measure of cell capability to respond to an energy demand through glycolysis. Conversely, 4,5-diCQA did not modify mitochondrial activity but increased glycolysis at low concentration in primary hepatocytes. All compounds tested improved cellular capacity to oxidize fatty acids. Overall, our results demonstrated the potential of test CQA-derivatives to modify mitochondrial function in hepatic cells. It is especially relevant in case of dysfunctional mitochondria in hepatocytes linked to hepatic steatosis during obesity, diabetes, and metabolic syndrome.

The effect of adiponectin in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) and the potential role of polyphenols in the modulation of adiponectin signaling

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide, as it affects up to 30 % of adults in Western countries. Moreover, NAFLD is also considered an independent risk factor for cardiovascular diseases. Insulin resistance and inflammation have been identified as key factors in the pathophysiology of NAFLD. Although the mechanisms associated with the development of NAFLD remain to be fully elucidated, a complex interaction between adipokines and cytokines appear to play a crucial role in the development of this condition. Adiponectin is the most common adipokine known to be inversely linked with insulin resistance, lipid accumulation, inflammation and NAFLD. Consequently, the focus has been on the use of new therapies that may enhance hepatic expression of adiponectin downstream targets or increase the serum levels of adiponectin in the treatment NAFLD. While currently used therapies show limited efficacy in this aspect, accumulating evidence suggest that various dietary polyphenols may stimulate adiponectin levels, offering potential protection against the development of insulin resistance, inflammation and NAFLD as well as associated conditions of metabolic syndrome. As such, this review provides a better understanding of the role polyphenols play in modulating adiponectin signaling to protect against NAFLD. A brief discussion on the regulation of adiponectin during disease pathophysiology is also covered to underscore the potential protective effects of polyphenols against NAFLD. Some of the prominent polyphenols described in the manuscript include aspalathin, berberine, catechins, chlorogenic acid, curcumin, genistein, piperine, quercetin, and resveratrol.

Metabolic Syndrome in Children and Adolescents: Is There a Universally Accepted Definition? Does it Matter?

The concept of metabolic syndrome (MetS) as a cluster of cardiovascular risk factors (obesity, altered glucose metabolism, dyslipidemia, and hypertension) has been around for more than 30 years. It is considered to be the result of complex interactions between centrally located fat, insulin resistance, subclinical inflammation, and other factors in genetically predisposed individuals. MetS diagnosis in adults has been linked to increased risk for cardiovascular disease (CVD) and type 2 diabetes mellitus (T2D). However, MetS in children and adolescents remains a controversial issue despite the extensive research in the field. It is still uncertain which definition should be used for its diagnosis in this age group, what is the clinical significance of such a diagnosis, and how reliably it can predict the future risk of developing CVD and T2D. Even if a child is diagnosed with MetS, management includes addressing each of the syndrome's components individually with weight loss and lifestyle modifications as the basic approach. Co-morbid conditions, such as nonalcoholic fatty liver disease, obstructive sleep apnea, and polycystic ovary syndrome should also be considered. It seems that MetS in children and adolescents should be used clinically as a conceptual framework for the identification of risk factors clustered around obesity and insulin resistance rather than a syndrome that needs to be diagnosed by measuring absolute "all-or-none" criteria.

Liver Fat and Cardiometabolic Risk Factors Among School-Age Children

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease is a major risk factor for cardiometabolic disease in adults. The burden of liver fat and associated cardiometabolic risk factors in healthy children is unknown. In a population-based prospective cohort study among 3,170 10-year-old children, we assessed whether both liver fat accumulation across the full range and nonalcoholic fatty liver disease are associated with cardiometabolic risk factors already in childhood.

APPROACH AND RESULTS

Liver fat fraction was measured by magnetic resonance imaging, and nonalcoholic fatty liver disease was defined as liver fat fraction ≥5.0%. We measured body mass index, blood pressure, and insulin, glucose, lipids, and C-reactive protein concentrations. Cardiometabolic clustering was defined as having three or more risk factors out of high visceral fat mass, high blood pressure, low high-density-lipoprotein cholesterol or high triglycerides, and high insulin concentrations. Nonalcoholic fatty liver disease prevalences were 1.0%, 9.1%, and 25.0% among children who were normal weight, overweight, and obese, respectively. Both higher liver fat within the normal range (<5.0% liver fat) and nonalcoholic fatty liver disease were associated with higher blood pressure, insulin resistance, total cholesterol, triglycerides, and C-reactive protein concentrations (P values < 0.05). As compared with children with <2.0% liver fat, children with ≥5.0% liver fat had the highest odds of cardiometabolic clustering (odds ratio 24.43 [95% confidence interval 12.25, 48.60]). The associations remained similar after adjustment for body mass index and tended to be stronger in children who were overweight and obese.

CONCLUSIONS

Higher liver fat is, across the full range and independently of body mass index, associated with an adverse cardiometabolic risk profile already in childhood. Future preventive strategies focused on improving cardiometabolic outcomes in later life may need to target liver fat development in childhood.

Predictors of non-alcoholic fatty liver disease (NAFLD) among children with obesity

Background The prevalence of childhood obesity and its related comorbidities in Malaysia are alarming. Malaysia ranked second in childhood obesity among South-east Asian countries with a prevalence of 12.7%. This study was conducted to investigate the prevalence of non-alcoholic fatty liver disease (NAFLD) among obese children and to ascertain the predictors associated with NAFLD. Methods NAFLD was diagnosed via ultrasonographic evidence of fatty liver in obese and overweight children who presented to the Paediatric Obesity Clinic of University Malaya Medical Centre (UMMC), Malaysia. Demographic, anthropometric, clinical and biochemical parameters were analysed and compared between the NAFLD and non-NAFLD groups. Statistical analyses were carried out. Results Twenty-one out of 33 obese and overweight children (63.6%) were found to have NAFLD. We found that 62% of our study population in the NAFLD group had metabolic syndrome based on the definition by the International Diabetes Federation (IDF). Mean body mass index (BMI), waist circumference (WC), triglyceride (TG) and alanine aminotransferase (ALT) were found to be significantly greater in the NAFLD group compared to the non-NAFLD group (35.2 [6.1] vs. 29.3 [4.7] kg/m2 [p-value 0.007]; 104.1 [11.4] vs. 94.1 [12] cm [p-value 0.034]; 1.5 [0.9] vs. 0.9 [0.3] mmol/L [p-value 0.002]; 60.7 [53.8] vs. 27.3 [13] U/L [p-value 0.007]). Multivariate regression analysis revealed TG as the independent predictor for NAFLD, with an odds ratio of 41.7 (95% confidence interval [CI] 0.001, 0.819) (p-value 0.04). Conclusions Prevalence of NAFLD among children who are obese and overweight is alarming with 62% having metabolic syndrome. TG was found to be a strong predictor for NAFLD.

Non-alcoholic fatty liver infiltration in children: an underdiagnosed evolving disease

Non-alcoholic fatty liver disease (NAFLD) constitutes the most common liver disease, one that is still underdiagnosed in pediatric populations (as well as in the general population), this due to the progressive increase in childhood obesity observed both in developed and developing countries during the last few decades. The pathophysiology of the disease has not been thoroughly clarified yet. The condition displays common pathways in adults and children; however, there are age-related differences. Unlike adults, children with NAFLD require extensive laboratory analysis, because underlying pathologies other than obesity may contribute to the evolution of the disease. Despite the presence of several serum markers and imaging techniques that contribute to NAFLD diagnosis, liver biopsy remains the gold standard diagnostic procedure. Early intervention and obesity prevention are mandatory, as NAFLD is reversible at an early stage. If left undiagnosed and untreated, NAFLD can progress to steatohepatitis (NASH) and subsequent liver failure, a potentially lethal complication. Of note, there are no treatment options when advanced liver fibrosis occurs. This review summarizes literature data on NAFLD in childhood indicating that this is an evolving disease and a significant component of the metabolic syndrome. Pediatricians should be aware of this entity, screening children at high risk and providing appropriate early management, in collaboration with pediatric subspecialists.

Obesity, adipocyte hypertrophy, fasting glucose, and resistin are potential contributors to nonalcoholic fatty liver disease in South Asian women

Purpose: Nonalcoholic fatty liver disease (NAFLD) is often referred to as the hepatic manifestation of the metabolic syndrome. The relationship between body weight, NAFLD, and insulin resistance is not well characterized in humans. Additionally, it is unclear why South Asians develop these complications at lower levels of obesity compared to their Western counterparts. Patients and methods: To address this question, we performed a cross-sectional study using a convenience sample of Sri Lankan adult females (n=34) and collected anthropometric data, adipose tissue specimens (for histology), and fasted serum samples (for metabolic and inflammatory markers). Hepatic steatosis was assessed by ultrasound scanning and used to classify participants as NAFL 0, NAFL 1, and NAFL 2. Results: Waist circumference significantly increased with increasing NAFL grade. Participants with NAFL had significantly higher body mass index, hip circumference, and fasting plasma glucose, as well as a higher mean adipocyte area in both abdominal subcutaneous and visceral areas, indicating a higher degree of adipocyte hypertrophy associated with fatty liver. There were, however, no differences in measures of dyslipidemia. Of the multiple adipokines measured, resistin was the only proinflammatory adipokine significantly elevated in NAFL 2. Conclusion: These findings indicate that measures of adiposity, fasting serum glucose, and resistin may be important indicators of NAFLD in South Asian women.

Metabolic and genetic markers' associations with elevated levels of alanine aminotransferase in adolescents

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), the most common chronic liver disease in adolescents, is a feature of metabolic syndrome (MetS). Obesity and insulin resistance (IR) are risk factors for NAFLD, as well as inflammation-related genetic markers. The relationship between metabolic or inflammation-related genetic markers and alanine aminotransferase (ALT) is not fully understood. We examined the relationship of MetS, metabolic and inflammation-related genetic markers with elevated ALT in adolescents.

METHODS

A total of 674 adolescents participated in a cross-sectional study in Guadalajara, Mexico. Elevated ALT (>40 IU/L), a surrogate marker of NAFLD, and MetS (International Diabetes Federation definition) were evaluated. Obesity, IR, lipids, C-reactive protein (CRP) and genetic markers (TNFA-308G>A, CRP+1444C>T, IL1RN and IL6-597/-572/-174 haplotype) were evaluated. Multivariate logistic regression was performed.

RESULTS

Elevated ALT was observed in 3% and 14.1% (total and obese, respectively) of the adolescents. Obesity (odds ratio [OR], 5.86; 95% confidence interval [95% CI], 1.16-25.89), insulin (OR, 8.51; 95% CI, 2.61-27.71), IR (OR, 9.10; 95% CI, 2.82-29.38), total cholesterol (TC) (OR, 3.67; 95% CI, 1.25-10.72), low-density lipoprotein-cholesterol (LDL-C) (OR, 3.06; 95% CI, 1.06-8.33), non-high-density lipoprotein-cholesterol (HDL-C) (OR, 3.88; 95% CI, 1.27-11.90) and IL1RN (OR, 4.64; 95% CI, 1.10-19.53) were associated with elevated ALT. Among males, ≥2 MetS criteria were associated with elevated ALT (OR, 4.22; 95% CI, 1.14-15.71).

CONCLUSIONS

Obesity, insulin, IR, high TC, high LDL-C, high non-HDL-C and IL1RN polymorphism were associated with elevated ALT. Among males, ≥2 MetS criteria were associated with elevated ALT. There is an urgent need to reduce obesity and IR in adolescents to prevent NAFLD.

Non-alcoholic fatty liver disease and its associations among adolescents in an urban, Sri Lankan community

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a common problem across the world. We aimed to determine the prevalence of NAFLD and its associations in Sri Lankan adolescents living in an urban Sri Lankan community.

METHOD

The study population consisted of the birth cohort of the year 2000, residing in the Ragama Medical Officer of Health area. Socio-demographic and anthropometric data [anthropometric measurements, blood pressure and total body fat distribution] of these adolescents were collected by trained data collectors. Fasting blood sugar, serum insulin, fasting serum lipids and serum alanine aminotransferase (ALT) levels were measured and an abdominal ultrasound was performed. NAFLD was diagnosed on established ultrasound criteria for fatty liver and absent alcohol consumption.

RESULTS

The study sample consisted of 499 adolescents [263 (51.8%) girls]. Forty two (8.4%) had NAFLD. NAFLD was significantly associated with being breast fed for less than 4 months (33.3% vs. 17.1 in controls, p = 0.02), higher waist circumference (prevalence risk ratio 83.3/20.3, 4.1, p < 0.0001), higher body mass index (prevalence risk ratio 40.5/4.8, 8.4, p < 0/0001),higher HOMA-IR (3.7 vs. 1.9, p < 0.0001) and high triglycerides (prevalence risk ratio 14.3/5.8, 2.5, p = 0.033). Adolescents with NAFLD also had a higher amount of total body fat (p < 0.001) and subcutaneous fat (p < 0.001) than those without NAFLD. The number of children with metabolic derangements was higher among adolescents with NAFLD than those without (85.8 vs 26.3 in controls, p < 0.0001), but a family history of hypertension, diabetes, myocardial infarction or dyslipidaemia were not.

CONCLUSION

Prevalence of NAFLD was high in Sri Lankan adolescents, and was associated with metabolic derangements, especially obesity, insulin resistance and early cessation of breast feeding.

Evaluation of Biomarkers in Egyptian Patients with Different Grades of Nonalcoholic Fatty Liver Disease

Background and Aims: Nonalcoholic fatty liver disease (NAFLD) is a silent disease; its spectrum includes simple steatosis, nonalcoholic steatohepatitis and fibrosis. Pro- and anti-inflammatory cytokines play roles in the pathogenesis of NAFLD and insulin resistance (IR). Moreover, plasma cell antigen-1 (PC-1) is related to IR and associated with NAFLD progression. Therefore, we aimed to detect biomarkers, ultrasonographic and anthropometric findings capable of differentiating NAFLD grades, since most previous investigators were concerned more with NAFLD patients without classifying them into grades. Methods: A total of 87 NAFLD patients (31 with grade 1 (mild NAFLD), 26 with grade 2 (moderate NAFLD) and 30 with grade 3 (severe NAFLD) were included in the study, in addition to 47 controls (grade 0). All subjects underwent ultrasonographic examination for NAFLD diagnosis. Serum interleukin-10 (IL-10), plasma interleukin-18 (IL-18) and plasma PC-1 levels were determined using enzyme-linked immunosorbent assay. Results: Homoeostasis model assessment (HOMA)-IR was higher in different NAFLD grades than in controls. Ultrasonographic and anthropometric findings and lipid profile indices (except for high-density lipoprotein cholesterol, which was decreased) were increased with NAFLD progression. Grade 3 patients showed significant increase in levels of IL-18 and significant decrease in IL-10 and PC-1 levels when compared to grade 1 patients. Conclusion: Anthropometric and ultrasonographic findings were valuable in differentiating NAFLD grades. IR is very important in NAFLD pathogenesis. IL-18, HOMA-index and PC-1 levels could be used to differentiate between NAFLD grades, together with other measurements.

Global Epidemiology of Nonalcoholic Fatty Liver Disease and Perspectives on US Minority Populations

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a clinical syndrome predicted to be the next global epidemic affecting millions of people worldwide. The natural course of this disease including its subtype, non-alcoholic steatohepatitis (NASH), is not clearly defined especially in the African-American segment of the US population.

AIMS

To conduct a review of the global epidemiology of NAFLD with emphasis on US minority populations.

METHODS

A thorough search of evidence-based literature was conducted using the Pubmed database and commercial web sources such as Medscape and Google Scholar.

RESULTS

NAFLD and its subtype NASH are becoming the principal cause of chronic liver disease across the world. In the US, Hispanics are the most disproportionately affected ethnic group with hepatic steatosis, and elevated aminotransferase levels, whereas African-Americans are the least affected. Genetic disparities involved in lipid metabolism seem to be the leading explanation for the lowest incidence and prevalence of both NAFLD and NASH in African-Americans.

CONCLUSIONS

The unprecedented rise in the prevalence of NAFLD globally requires an initiation of population cohort studies with long-term follow-up to determine the incidence and natural history of NAFLD and its underrepresentation in African-Americans. Future studies should also focus on the delineation of the interplay between genetic and environmental factors that trigger the development of NAFLD and NASH.

Relationship between Neck Circumference and Non-Alcoholic Fatty Liver Disease in Childhood Obesity

OBJECTIVE

The aim of this study was to establish the association between anthropometric parameters and non-alcoholic fatty liver disease (NAFLD) and to determine the most reliable measurement as a parameter in predicting NAFLD.

METHODS

Two-hundred fifty-three obese children of ages 10 to 18 years were enrolled in this study. Anthropometric data and metabolic parameters such as fasting blood glucose, insulin and lipid levels, were measured. Liver function tests were assessed. NAFLD was determined by ultrasound.

RESULTS

Most metabolic parameters and anthropometric indices were significantly higher in children with NAFLD. A univariate logistic regression analysis was performed, taking NAFLD status as the dependent variable and anthropometric parameters as the independent variables. NAFLD was affected significantly by the anthropometric values. The multiple logistic regression analysis showed that neck circumference (NC) was the only parameter which determined the risk in both genders. Each 1 cm increase in the NC increased the risk of NAFLD 1.544-fold (p<0.001, 95% confidence interval (CI): 1.357-2.214) in the boys and 1.733-fold (p=0.001, 95% CI: 1.185-2.012) in the girls. Receiver operating characteristic analysis was performed to compare the reliability of anthropometric measurements. NC was observed to be a better indicator.

CONCLUSION

Measurement of the NC was shown to be associated with NAFLD in children. We suggest the use of NC as a novel, simple, practical, and reliable anthropometric index in predicting children at risk for NAFLD.

Comparison between a pediatric health promotion center and a pediatric obesity clinic in detecting metabolic syndrome and non-alcoholic fatty liver disease in children

This study was done to evaluate the efficacy of health check-ups in children in detecting metabolic syndrome and non-alcoholic fatty liver disease (NAFLD) by comparing the pediatric health promotion center with the pediatric obesity clinic. Children who visited a pediatric health promotion center (n=218) or a pediatric obesity clinic (n=178) were included. Anthropometric data, blood pressure, laboratory tests, and abdominal ultrasonography were evaluated. Two different criteria were applied to diagnose metabolic syndrome. The prevalence of metabolic syndrome in the 2 units was 3.2%-3.7% in a pediatric health promotion center and 23%-33.2% in a pediatric obesity clinic. Significant differences were observed in the prevalence of each component of metabolic syndrome between the 2 units including abdominal adiposity, blood pressure, serum triglycerides, and fasting blood glucose (P<0.05). The prevalence of NAFLD was 8.7% and 71.9% in the 2 units according to liver enzymes and 5.9% and 61.8% according to ultrasonography (P<0.05). The prevalence of metabolic syndrome and NAFLD was higher among patients visiting the obesity clinic targeting obese children than that among patients visiting the health promotion center offering routine check-ups. An obesity-oriented approach is required to prevent obesity-related health problems in children.

Improvement in nonalcoholic fatty liver disease and metabolic syndrome in adolescents undergoing bariatric surgery

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children. It is linked to obesity and the metabolic syndrome (MS), predisposing to future cirrhosis. The objective of this study was to demonstrate the effects that weight loss achieved with laparoscopic adjustable gastric band (LAGB) has on the metabolic parameters and NAFLD scores of obese adolescents with evidence of fatty liver disease.

METHODS

Adolescents undergoing LAGB were evaluated for NAFLD with evidence of fatty liver on preoperative sonogram, serum biochemistry, or both between 2005 and 2011. Primary endpoint was change in NAFLD scores after LAGB and secondary endpoint change in MS criteria.

RESULTS

Fifty-six out of 155 adolescents had evidence of fatty liver disease at presentation. The group consisted of 17 (30%) male and 39 (70%) females, mean age 16.1 years (range 14-17.8 yr). Preoperative body mass index (BMI) was 48.8 kg/m(2) (±7) dropping to 37.9 kg/m(2) (±8.3) at 12 months and 36.8 kg/m(2) (±8.2) at 24 months. Fifteen (27%) patients met the criteria for MS. When comparing 1-year postsurgery to presurgery, the NAFLD score decreased by an average of .68 (SD = 1.03, P<.01). The 2-year NAFLD score decreased by a mean of .38 (SD = .99, P = .01). The reoperation rate for band/port related complications was 10.7% at 2 years with no mortality. MS rates improved from 27% to 2% at 2 years (P< .01).

CONCLUSIONS

LAGB is a safe and effective operation for obese adolescents with NAFLD. There was significant improvement in NAFLD scores and resolution of MS.

Prevalence, risk factors, and predictors of nonalcoholic fatty liver disease among schoolchildren: a hospital-based study in Alexandria, Egypt

BACKGROUND AND STUDY AIMS

Nonalcoholic fatty liver disease (NAFLD) is an emerging problem in children and adolescents worldwide. This study was done to investigate the prevalence of NAFLD in children and adolescents as well as to determine the associated risk factors of fatty liver and to explore the ability of some obesity indices to predict and consequently be used as a screening method of fatty liver disease at certain cutoff points in schoolchildren.

PATIENTS AND METHODS

A cross-sectional, nested case-control study was carried out. Cases and controls were randomly selected from outpatient schoolchildren aged 6-18years attending the radiology clinic at Sporting Health Insurance Paediatric Hospital in Alexandria. They were subjected to ultrasonic examination as well as complete anthropometric and laboratory measurements including fasting plasma glucose (FPG) level, fasting insulin, alanine aminotransferase (ALT) level, and lipid profile.

RESULTS

Fatty liver was prevalent in schoolchildren (15.8%) and increased significantly with age (p=0.004). Positive family history of diabetes mellitus (DM), hypertension (HTN), obesity, and liver disease were all statistically significant risk factors for fatty liver. Waist circumference (WC), body mass index (BMI) and its Z-score were significantly sensitive predictors. BMI was considered the best predictor of paediatric NAFLD at a cutoff=22.9. NAFLD was significantly associated with high triglycerides (TGs), low high-density lipoprotein cholesterol (HDL), homoeostatic model assessment (HOMA) percentile, and the number of metabolic syndrome (MS) components.

CONCLUSION

Paediatric NAFLD is a substantial problem in schoolchildren and has a close relationship with obesity, dyslipidaemia, insulin resistance (IR), and consequently MS. BMI and WC can be used as useful predictors and screening tools for NAFLD in schoolchildren.

Relationship between viseral fat thickness measured by ultrasonography and nonalcoholic fatty liver disease

AIM: To investigate relationship between visceral fat thickness measured by ultrasonography and nonalcoholic fatty liver disease (NAFLD).

METHODS: One hundred and seventy subjects were enrolled and divided into two groups: a NAFLD group (n = 110) and a healthy control group (n = 60). Blood pressure (BP), height, weight, waist circumference (WC), hip circumference, body mass index (BMI), waist-hip ratio (WHR), triglycerides (TG), total cholesterol (TC), fasting blood glucose, liver function and fasting insulin were measured in each subject, and the homeostasis model assessment of insulin resistance (HOMA-IR) was calculated according to the typical HOMA model. Visceral fat thickness was measured by ultrasonography.

RESULTS: The visceral fat thickness, BMI, WHR and HOMA-IR were significantly higher in the NAFLD group than in the normal control group (P < 0.05 for all). The visceral fat thickness had significant statistical difference between the mild, moderate and severe NAFLD groups. Correlation analysis showed that there were significantly positive correlations between visceral fat thickness and BMI, WHR and HOMA-IR (r = 0.62, 0.509, 0.596, P < 0.05 for all).

CONCLUSION: Visceral fat thickness measured by ultrasonography may be an important index for diagnosing nonalcoholic fatty liver disease.

Current role of fenofibrate in the prevention and management of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a common health problem with a high mortality burden due to its liver- and vascular-specific complications. It is associated with obesity, high-fat diet as well as with type 2 diabetes mellitus (T2DM) and metabolic syndrome (MetS). Impaired hepatic fatty acid (FA) turnover together with insulin resistance are key players in NAFLD pathogenesis. Peroxisome proliferator-activated receptors (PPARs) are involved in lipid and glucose metabolic pathways. The novel concept is that the activation of the PPARα subunit may protect from liver steatosis. Fenofibrate, by activating PPARα, effectively improves the atherogenic lipid profile associated with T2DM and MetS. Experimental evidence suggested various protective effects of the drug against liver steatosis. Namely, fenofibrate-related PPARα activation may enhance the expression of genes promoting hepatic FA β-oxidation. Furthermore, fenofibrate reduces hepatic insulin resistance. It also inhibits the expression of inflammatory mediators involved in non-alcoholic steatohepatitis pathogenesis. These include tumor necrosis factor-α, intercellular cell adhesion molecule-1, vascular cell adhesion molecule-1 and monocyte chemoattractant protein-1. Consequently, fenofibrate can limit hepatic macrophage infiltration. Other liver-protective effects include decreased oxidative stress and improved liver microvasculature function. Experimental studies showed that fenofibrate can limit liver steatosis associated with high-fat diet, T2DM and obesity-related insulin resistance. Few studies showed that these benefits are also relevant even in the clinical setting. However, these have certain limitations. Namely, these were uncontrolled, their sample size was small, fenofibrate was used as a part of multifactorial approach, while histological data were absent. In this context, there is a need for large prospective studies, including proper control groups and full assessment of liver histology.

Intra-abdominal fat is related to metabolic syndrome and non-alcoholic fat liver disease in obese youth

BACKGROUND

Previous studies have shown an association between adiposity, especially intra-abdominal adipose tissue, and hemodynamic/metabolic comorbidities in adults, however it is not clear in pediatric population. The aim of the study was to analyze the relationship between non-alcoholic fatty liver disease (NAFLD) and components of metabolic syndrome (MS) with values of intra-abdominal (IAAT) and subcutaneous (SCAT) adipose tissue in obese children and adolescents.

METHODS

Cross-sectional study.

SUBJECTS

182 obese sedentary children and adolescents (aged 6 to 16 y), identified by the body mass index (BMI).

MEASUREMENTS

Body composition and trunk fat by dual-energy X-ray absorptiometry- DXA; lipid profile, blood pressure and pubertal stage were also assessed. NAFLD was classified as absent (0), mild (1), moderate (2) and severe (3), and intra-abdominal and subcutaneous abdominal fat thickness were identified by ultrasound. The MS was identified according to the cut offs proposed by World Health Organization adapted for children and adolescents. The chi-square test was used to compare categorical variables, and the binary logistic regression indicated the magnitude of the associations adjusted by potential cofounders (sex, age, maturation, NAFLD and HOMA-IR).

RESULTS

Higher quartile of SCAT was associated with elevated blood pressure (p = 0.015), but not associated with NAFLD (p = 0.665). Higher IAAT was positively associated with increased dyslipidemia (p = 0.001), MS (p = 0.013) and NAFLD (p = 0.005). Intermediate (p = 0.007) and highest (p = 0.001) quartile of IAAT were also associated with dyslipidemia, independently of age, sex, maturation, NAFLD and HOMA-IR (homeostatic model assessment-insulin resistance).

CONCLUSION

Obese children and adolescents, with higher IAAT are more prone to develop MS and NAFLD than those with higher values of SCAT, independent of possible confounding variables.

Liver steatosis in Polish children assessed by medicolegal autopsies

BACKGROUND

Cases of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are increasing in the pediatric population. Their growing prevalence coincides with the obesity epidemic. Assessment of the incidence requires liver biopsies on a representative population sample, which are hampered by the absence of indications for invasive examination on children without clinical symptoms. The aim of the current study was to assess the incidence of liver steatosis in the population of children up to 18 years old from Lower Silesia.

METHODS

We retrospectively reviewed 342 medico-legal autopsy reports from 2000 to 2009. We separated a group of 256 children whose death was caused by trauma. Liver steatosis was diagnosed according to the results of histopathological examinations and typical macroscopic imaging.

RESULTS

In the 265 children who died from trauma, liver steatosis was reported in 11 (4.2%) children (6 boys) aged between 6 months and 18 years old. Six of the 11 children (54.5%) were found to be overweight. In all 342 children, steatosis was found in 18 (5.3%) children (13 boys), while NASH was diagnosed in 1 (0.3%). Excess body weight was observed in 55.6% (10/18) of children with steatosis.

CONCLUSIONS

Liver steatosis can occur at any age, even in infancy. Being overweight is a very important risk factor. Gross examination of the liver is insufficient for the diagnosis of steatosis because of its lower sensitivity and specificity. Verification of liver steatosis requires reference histopathological examination.

[Non-alcoholic fatty liver disease and its association with clinical and biochemical variables in obese children and adolescents: effect of a one-year intervention on lifestyle]

OBJECTIVE

To study the frequency of non-alcoholic fatty liver disease (NAFLD), its relationship to clinical and biochemical variables, and the effect 12-month's lifestyle intervention in obese children and adolescents.

METHODS

Thirty-six obese patients aged 7 to 18 years, 42% female and 58% male, 72.2% prepubertal and 27.8% pubertal, were selected. Anthropometric measurements and glucose, insulin (baseline and after a glucose load), lipid profile, C-reactive protein, and aminotransferase tests were performed before and 12 months after dietary and physical activity intervention. Liver ultrasound was performed to determine the presence of NAFLD.

RESULTS

NAFLD was found in 66.7% (n=24), and was mild in 30.6%, moderate in 27.8%, and severe in 8.3%. Subjects with NAFLD had higher body mass index (BMI, p=0.007), waist (p=0.005), fat area (p=0.002), basal insulin (p=0.01), and HOMA-IR (p=0.008) values and lower QUICKI (p=0.02) values than those with no NAFLD. After intervention, physical activity increased (p=0.0001) and calorie intake remained unchanged. NAFLD disappeared in 9 patients (37.5%, p=0.02) and disease severity decreased in 3 patients (12.5%). In addition, BMI Z-score (p=0.005), fat area (p=0.0001), basal insulin (p<0.05), insulin resistance (p<0.005), lipid profile (p<0.03), and transaminases decreased. Weight loss was the main variable accounting for NAFLD improvement.

CONCLUSION

This group of obese children and adolescents showed a high frequency of NAFLD. The lifestyle intervention with weight reduction is effective for the treatment of NAFLD.

Can we modify the intrauterine environment to halt the intergenerational cycle of obesity?

Child obesity is a global epidemic whose development is rooted in complex and multi-factorial interactions. Once established, obesity is difficult to reverse and epidemiological, animal model, and experimental studies have provided strong evidence implicating the intrauterine environment in downstream obesity. This review focuses on the interplay between maternal obesity, gestational weight gain and lifestyle behaviours, which may act independently or in combination, to perpetuate the intergenerational cycle of obesity. The gestational period, is a crucial time of growth, development and physiological change in mother and child. This provides a window of opportunity for intervention via maternal nutrition and/or physical activity that may induce beneficial physiological alternations in the fetus that are mediated through favourable adaptations to in utero environmental stimuli. Evidence in the emerging field of epigenetics suggests that chronic, sub-clinical perturbations during pregnancy may affect fetal phenotype and long-term human data from ongoing randomized controlled trials will further aid in establishing the science behind ones predisposition to positive energy balance.

Association between Insulin Resistance, Metabolic Syndrome and Nonalcoholic Fatty Liver Disease in Chinese Adults

BACKGROUND

The aim of this study was to assess the association between insulin resistance, metabolic syndrome and nonalcoholic fatty liver disease (NAFLD) in Chinese adults.

METHODS

Fifty five subjects with NAFLD and 55 controls were enrolled for the study. Waist circumference, blood pressure, plasma triglyceride, high density lipoprotein cholesterol and fasting plasma glucose concentrations and homeostasis model assessment of insulin resistance (HOMA-IR) values as an index used to quantify insulin resistance were measured and analyzed. Logistic regression was analyzed to predict independent risk factors of NAFLD.

RESULTS

The prevalence of metabolic syndrome in NAFLD group was obviously higher than in controls group (47.3% VS 3.6%, P<0.001). There were all significant differences of each component of metabolic syndrome and HOMA-IR values in comparison of nonalcoholic fatty liver disease (NAFLD) and controls group. In a logistic regression analysis, age, diastolic blood pressure, waist circumference and HOMA-IR were the covariates independently associated with the presence of NAFLD (Odds Ratio=1.107, 1.083, 1.218 and 16.836; 95% CI: 1.011∼1.211, 1.001∼1.173, 1.083∼1.370 and 3.626∼78.168, respectively; P<0.05)

CONCLUSION

NAFLD was closely associated with metabolic syndrome and insulin resistance was a very strong predictor of NAFLD.

The role of innate cells is coupled to a Th1-polarized immune response in pediatric nonalcoholic steatohepatitis

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is a chronic inflammatory liver disease influenced by risk factors for the metabolic syndrome. In adult patients, NASH is associated with an altered phenotype and functionality of peripheral immune cells, the recruitment of leukocytes and intrahepatic activation, and an exacerbated production of reactive oxygen species (ROS) and cytokines. It remains unclear if the previously described differences between pediatric and adult nonalcoholic fatty liver diseases also reflect differences in their pathogenesis.

AIMS

We aimed to investigate the phenotype and functionality of circulating immune cells and the potential contribution of liver infiltrating leukocytes to the immunological imbalance in pediatric NASH.

RESULTS

By a real-time PCR-based analysis of cytokines and immunohistochemical staining of liver biopsies, we demonstrated that the hepatic microenvironment is dominated by interferon-gamma (IFN-γ) but not interleukin-4 and is infiltrated by a higher number of CD8(+) cells in pediatric NASH. The number of infiltrating neutrophils positively correlated with ROS generation by peripheral polymorphonuclear cells. By a flow cytometric analysis of peripheral blood lymphocytes, a distinctive increase in CD8(+) CD45RO and CD8(+) CD45RA subpopulations and an increased production of IFN-γ by CD4(+) and CD8(+) cells were shown. The production of ROS following PMA stimulation was augmented in circulating neutrophils but not in monocytes.

CONCLUSION

In sum, the distinctive phenotype and functionality of infiltrating and circulating cells suggest that the role of innate cells is coupled to a Th1-polarized immune response in pediatric NASH.

Mechanisms and implications of age-related changes in the liver: nonalcoholic Fatty liver disease in the elderly

Nonalcoholic fatty liver disease (NAFLD) is hepatic steatosis associated with metabolic abnormalities such as overweight/central obesity, insulin resistance, type 2 diabetes (T2D), and dyslipidemia. NAFLD is becoming the most common liver disease in contemporary society, with the highest prevalence in those over 60 years. NAFLD pathology ranges from simple steatosis to a necroinflammatory fibrosing disorder called steatohepatitis (SH), the latter associated with high risk of developing cirrhosis, often occuring in the seventh to ninth decades of life. While the main health implications of NAFLD are increased risk of developing T2D, cardiovascular diseases, and common cancers, there is substantantially increased standardized mortality, and deaths from decompensated cirrhosis and hepatocellular carcinoma (HCC). Little is known about the interactive effects of ageing and NAFLD, with most studies focusing on the younger population. This paper summarises the epidemiology, pathogenesis, and clinical course of NAFLD, with particular attention to persons over age 60 years. An approach to the management of NASH and its complications in the elderly, will also be presented here.

Systematic review: association of polycystic ovary syndrome with metabolic syndrome and non-alcoholic fatty liver disease

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common disorder for women of child-bearing age and is associated with metabolic syndrome (MS).

AIM

To assess the literature for associations between polycystic ovary syndrome and non-alcoholic fatty liver disease (NAFLD).

METHODS

We performed a systematic review using PubMed-search for peer-reviewed articles related to polycystic ovary syndrome and NAFLD. Articles were summarised and grouped according to different sections defining interactions of polycystic ovary syndrome with metabolic syndrome and non-alcoholic fatty liver disease as well as risk factors, pathogenic pathways and treatment options.

RESULTS

Obesity is a common factor involved in both polycystic ovary syndrome and non-alcoholic fatty liver disease. Obesity causes non-alcoholic fatty liver disease and aggravates hirsutism and menstrual disorders in polycystic ovary syndrome. Insulin resistance, a hallmark of metabolic syndrome is observed in 50-80% of women with polycystic ovary syndrome and patients with non-alcoholic fatty liver disease. Recent findings suggest that women with polycystic ovary syndrome may be at risk for developing non-alcoholic fatty liver disease and conversely, non-alcoholic fatty liver disease may be a risk for polycystic ovary syndrome. Based on the association of polycystic ovary syndrome and other metabolic abnormalities, such as insulin resistance, hyperandrogenism, obesity and non-alcoholic fatty liver disease, the candidate genes have been speculated for polycystic ovary syndrome. Closer scrutiny of these genes placed most of their proteins at the crossroads of three highly inter-related conditions: metabolic syndrome, obesity and non-alcoholic fatty liver disease. In most studies, the prevalence of both polycystic ovary syndrome and non-alcoholic fatty liver disease rises proportionally to the degree of insulin resistance and increases in the mass of adipose tissue.

CONCLUSIONS

Non-alcoholic fatty liver disease is considered as the hepatic manifestation of metabolic syndrome. Similarly, it seems appropriate to consider polycystic ovary syndrome as the ovarian manifestation of metabolic syndrome. Both these conditions can co-exist and may respond to similar therapeutic strategies.

The changing face of hepatitis in boys with haemophilia associated with increased prevalence of obesity

Hepatitis in children with haemophilia was historically most often associated with transfusion-transmitted infections. However, with the use of recombinant clotting factor concentrates, acquisition of such infections has now become rare. We studied the profile of hepatitis in North-American children with haemophilia in the modern era of safe blood products and excess childhood obesity. A total of 173 boys (<18 years) registered in the Pediatric Comprehensive Care Haemophilia Program were included in this retrospective study. Hospital records were reviewed for baseline data, serial height and weight measurements and serial alanine aminotransferase (ALT) levels. A body mass index (BMI) ranking was available for 170 boys, of whom 25 (14.7%, 95% CI 9.7-20.9%) were obese. The rate of obesity was higher in severe haemophilic boys. Compared with the general childhood population, the rate of obesity trended towards being higher in young haemophilic boys (2-5 years), but was similar in other age groups. A persistently high ALT (≥80 U L(-1) ) was documented in 5 boys and was associated with obesity. Three boys had clinical and imaging studies compatible with non-alcoholic fatty liver disease (NAFLD). Overweight and obesity are common among haemophilic boys, especially those who are younger and with severe disease. In this large group of haemophilic boys, chronic viral hepatitis was rare and NAFLD was a more common cause of liver disease. Overweight and obese haemophilic boys should be evaluated for NAFLD and interventional programmes should be designed to reduce the potential complications associated with obesity.

Iron load and liver enzymes in 10- and 13-year-olds

OBJECTIVES

Iron plays a pivotal role in adult steatosis, but its role in child and adolescent steatosis is unclear. We investigated the effect of dietary iron, serum iron, and ferritin on serum transaminases and γ-glutamyltransferase in 10- and 13-year-olds.

PATIENTS AND METHODS

The study included 4894 fifth and eighth graders enrolled between 2006 and 2009 in all schools in Shunan City, Japan. Multiple regression analyses were performed with adjustments for grade, sex, z score of the body mass index, serum lipids, plasma glucose, frequency of sports activities, having a single parent, number of siblings, tobacco smoking behavior, passive smoking at home, resident areas, and schools, using linear mixed models. In addition, we analyzed ferritin and insulin resistance in randomly selected subset of participants.

RESULTS

Dietary iron intake was positively associated with serum alanine aminotransferase levels (standardized coefficient β = 2.35, P = 0.019). Serum iron concentrations were associated with transaminase and γ-glutamyltransferase levels (β = 3.22, and 4.05, respectively, P < 0.01). In the subset of 421 subjects with further serum analysis, serum ferritin levels were significantly associated with serum enzyme levels (β = 2.43-3.35; P < 0.05) and showed significant odds ratio for the elevated alanine aminotransferase levels (1.05 for 1 SD with 95% confidence intervals 1.02-1.08). However, iron load did not show a positive association with insulin resistance.

CONCLUSIONS

Although an effect size for iron is small in regression analyses, iron is implicated in increased transaminase levels in prepubertal and pubertal children.

Nonalcoholic fatty liver disease in adolescents receiving valproic acid

OBJECTIVE

The aim of this study was to investigate the association between the metabolic derangements induced by valproic acid (VPA) and ultrasound-diagnosed nonalcoholic fatty liver disease (NAFLD) in adolescents.

METHODS

Using a cross-sectional design, we evaluated 86 adolescents with epilepsy who had received VPA monotherapy. Subjects for comparison were 67 normal-weight and 43 weight-matched adolescents. Participants underwent hepatic ultrasound, anthropometric evaluations, and biochemical tests.

RESULTS

Although the occurrence of ultrasound-diagnosed NAFLD was higher in VPA-treated patients than in normal-weight controls (36.0% vs 7.5%, P<0.001), it was similar in VPA-treated patients and weight-matched controls (36.0% vs 34.9%, P>0.05). The identified predictors of NAFLD in VPA-treated patients were abdominal obesity (OR=3.2, 95% CI=2.1-6.8), insulin resistance (OR=2.8, 95% CI=1.7-5.2), metabolic syndrome (OR=2.6, 95% CI=1.4-4.8), and generalized obesity (OR=1.9, 95% CI=1.2-3.7).

CONCLUSION

Valproic acid monotherapy is associated with NAFLD in a high percentage of adolescents with epilepsy who have typical VPA-related metabolic disturbances.

Mechanisms and implications of age-related changes in the liver: nonalcoholic Fatty liver disease in the elderly

Nonalcoholic fatty liver disease (NAFLD) is hepatic steatosis associated with metabolic abnormalities such as overweight/central obesity, insulin resistance, type 2 diabetes (T2D), and dyslipidemia. NAFLD is becoming the most common liver disease in contemporary society, with the highest prevalence in those over 60 years. NAFLD pathology ranges from simple steatosis to a necroinflammatory fibrosing disorder called steatohepatitis (SH), the latter associated with high risk of developing cirrhosis, often occuring in the seventh to ninth decades of life. While the main health implications of NAFLD are increased risk of developing T2D, cardiovascular diseases, and common cancers, there is substantantially increased standardized mortality, and deaths from decompensated cirrhosis and hepatocellular carcinoma (HCC). Little is known about the interactive effects of ageing and NAFLD, with most studies focusing on the younger population. This paper summarises the epidemiology, pathogenesis, and clinical course of NAFLD, with particular attention to persons over age 60 years. An approach to the management of NASH and its complications in the elderly, will also be presented here.

Nonalcoholic fatty liver disease and nonalcoholic steatohepatitis in Japan

During the past 20 to 30 years, the frequency of patients presenting with nonalcoholic fatty liver diseases (NAFLD) has increased gradually in Japan in proportion to the increase in the population with life-style related diseases. We describe here the current status of the clinical and basic aspects of research into NAFLD in Japan. The increase in the incidence of life-style-related diseases has resulted in an increase in NAFLD throughout the past 20 to 30 years. The rate of obesity in the population is not high compared to western countries but the incidence of NAFLD is similar to those countries. In 2008 we started a nationwide study of NAFLD which has been supported by the Ministry of Labor and Welfare Japan. In this project, we planned to investigate the epidemiology, genetic backgrounds and biochemical markers, and liver injury in patients with diabetes mellitus (DM) and hepatocellular carcinoma in NASH, and treatment of NASH. Approximately 20 to 25% of DM patients showed NAFLD in which the prevalence of NASH might be more than 30 to 40%. Fortunately, we have been able to obtain very interesting results from our group studies, including single necleotide polymorphisms (SNPs) which will be published in the near future.

Pediatric nonalcoholic fatty liver disease: A clinical and laboratory challenge

The true prevalence of pediatric nonalcoholic fatty liver disease (NAFLD) is unknown. Challenges in determining the population prevalence of NAFLD include the type of test (and the reference intervals used to define normal and abnormal), the type of population (general population, hospital series), the demographic characteristics of the population sampled, and the nature of the study design. The natural history of pediatric NAFLD remains uncertain. The issue of when to perform a liver biopsy in children with suspected NAFLD remains controversial. Children with NAFLD but normal alanine aminotransferase are rarely investigated. However, evidence of alterations in glucose metabolism parameters should prompt a better understanding of the natural history of pediatric NAFLD not only in terms of the progression of liver disease but also regarding its potential relationship with other health outcomes such as type 2 diabetes mellitus and cardiovascular disease. This evidence could make liver biopsy mandatory in the majority of cases at risk of progressive and severe hepatic and extrahepatic disease. This conclusion, however, raises the question of the feasibility of liver biopsy assessment in an extremely large at risk population, and of the cost/effectiveness of this policy. There is a considerable, continuous interest in reliable, noninvasive alternatives that will allow the prognosis of pediatric NAFLD to be followed in large community or population-based studies.

Nonalcoholic fatty liver disease in Japanese junior high school students: its prevalence and relationship to lifestyle habits

BACKGROUND

Despite the increase in nonalcoholic fatty liver disease (NAFLD) in Japanese adults, its prevalence in adolescents remains unclear. This prompted us to evaluate the incidence and clinical characteristics of NAFLD among junior high school students.

METHODS

A population-based cross-sectional study was conducted among students in a single junior high school in Nagano prefecture. Serum alanine aminotransferase (ALT) and gamma-glutamyltransferase (gammaGT) measurements and abdominal ultrasonography were performed in 249 and 288 students in 2004 and 2007, respectively. In the latter survey, student lifestyle habits were also assessed, using questionnaires.

RESULTS

The prevalence of NAFLD was 4.4% and 4.5% in 2004 and 2007, respectively, which was lower than that of obesity (10.0% and 5.9%). Body mass index and ALT and gammaGT levels increased significantly with hepatic steatosis severity. Multivariate logistic regression analysis demonstrated that the presence of obesity and an ALT level of 30 U/L or more were independent predictors of NAFLD (odds ratio 16.9, P<0.001 and odds ratio 16.6, P=0.001, respectively). The ratios of students commuting to and from school by car and not doing sports outside of school were higher in NAFLD students compared with non-NAFLD ones. Such tendencies were observed independently of the presence of obesity. Additionally, one obese student with severe steatosis and liver dysfunction was diagnosed as having nonalcoholic steatohepatitis (NASH).

CONCLUSIONS

Approximately 4% of junior high school students had NAFLD that was primarily associated with obesity and reduced daily physical activity. Serum ALT measurement during school check-ups is recommended for the early detection of young adolescent NAFLD/NASH.