Risk factors for hepatic steatosis in adults with cystic fibrosis: Similarities to non-alcoholic fatty liver disease

AIM To investigate the clinical, biochemical and imaging characteristics of adult cystic fibrosis(CF) patients with hepatic steatosis as compared to normal CF controls.METHODS We performed a retrospective review of adult CF patients in an academic outpatient setting during 2016. Baseline characteristics, genetic mutation analysis as well as laboratory values were collected. Abdominal imaging(ultrasound, computed tomography, magnetic resonance) was used to determine presence of hepatic steatosis. We compare patients with hepatic steatosis to normal controls.RESULTS Data was collected on 114 patients meeting inclusion criteria. Seventeen patients(14.9%) were found to have hepatic steatosis on imaging. Being overweight(BMI 25)(P = 0.019) and having a higher pp FEV1(75 vs 53, P = 0.037) were significantly associated with hepatic steatosis. Patients with hepatic steatosis had a significantly higher median alanine aminotransferase level(27 vs 19, P = 0.048). None of the hepatic steatosis patients had frank CF liver disease, cirrhosis or portal hypertension. We found no significant association with pancreatic insufficiency or CF related diabetes.CONCLUSION Hepatic steatosis appears to be a clinically and phenotypically distinct entity from CF liver disease. The lack of association with malnourishment and the significant association with higher BMI and higher pp FEV1 demonstrate similarities with non-alcoholic fatty liver disease. Long term prospective studies are needed to ascertain whether CF hepatic steatosis progresses to fibrosis and cirrhosis.     

2型糖尿病患者合并非酒精性脂肪肝及脂肪肝纤维化的危险因素分析

目的：探讨2型糖尿病（T2DM）患者合并非酒精性脂肪肝（NAFLD）及脂肪肝纤维化的危险因素。方法采集2008年5月至2009年12月期间,上海交通大学附属第六人民医院内分泌科住院的1109例T2DM患者的病史资料、生化指标、肝脏超声检查结果,根据B超检查结果将患者分为T2DM组和T2DM合并NAFLD组,采用非酒精性脂肪肝纤维化评分（NAFLDFS）的高诊断阈值（＞0.676）、低诊断阈值（＜-1.455）将T2DM合并NAFLD组分为纤维化亚组、不确定亚组、无纤维化亚组进行分析。结果（1）T2DM合并NAFLD患者体质量指数（BMI）、腰围（WC）、臀围（HC）、腰臀比（WHR）、舒张压（DBP）、丙氨酸转氨酶（ALT）、天冬氨酸转氨酶（AST）、谷氨酰转肽酶（GGT）、总胆红素（TBIL）、总胆固醇（TC）、甘油三酯（TG）、低密度脂蛋白胆固醇（LDL-C）、尿酸（UA）、空腹血糖（FPG）、餐后2h血糖（2hPBG）、空腹C肽（FCP）、FCP代替胰岛素改良稳态模型指数（HOMA-C肽）均更高（P＜0.01或P＜0.05）,而年龄、糖尿病病程、高密度脂蛋白胆固醇（HDL-C）则显著低于T2DM患者（P＜0.01,表1）。（2）逐步logistic回归提示BMI[比值比（OR）＝1.325,95%CI 1.249～1.406]、ALT（OR＝1.025,95%CI 1.013～1.038）、TG（OR＝1.283,95%CI 1.105～1.490）是T2DM合并NAFLD的危险因素,HDL（OR＝0.532,95%CI 0.286～0.989）则是保护因素。（3） T2DM合并NAFLD患者中,纤维化亚组占13.4%。与无纤维化及不确定两亚组比较,年龄、病程、BMI、WC、HC、收缩压（SBP）、AST/ALT、GGT、糖化血红蛋白（HbA1c）显著增加（P＜0.01）,然而ALT、白蛋白（ALB）、TG、血小板（Plt）显著减少（P＜0.01或P＜0.05）,差异具有统计学意义。（4）有序多因素logistic回归提示,年龄、BMI、ALB、AST/ALT、Plt是T2DM合并NAFLD肝纤维化的危险因素。结论住院T2DM合并NAFLD患者比例较大,与BMI     

The association between steatosis and liver damage in transfusion-dependent beta thalassaemia patients

Non-alcoholic fatty liver disease (NAFLD) is a global health problem. Iron is the leading cause of liver damage in patients with transfusion-dependent thalassaemia (TDT), and data on the contribution of NAFLD to liver damage in TDT is lacking. Forty-five heavily transfused TDT patients who did not have biochemical or ultrasonic evidence of liver cirrhosis were evaluated for effects of iron overload, including the presence of diabetes mellitus, hypogonadism, serum ferritin, R2-MRI-liver, and liver enzymes alanine aminotransferase and aspartate aminotransferase. Liver fibrosis and steatosis were estimated using transient elastography (TE). Nine (20%) patients had significant steatosis (S1), and their body mass index (BMI) and liver fibrosis scores were higher than in patients without significant steatosis (S0) (p = 0.03 and p = 0.004, respectively). On regression analysis, the controlled attenuation parameter (CAP) score (i.e., degree of liver steatosis) was associated only with increasing BMI. The TE score (i.e., degree of liver fibrosis) was associated with increasing age, CAP score, male gender, and presence of diabetes. Neither liver steatosis nor fibrosis showed significant association with the liver iron concentration or iron-related organ damage (hypogonadism). In this cohort of TDT patients, steatosis of the liver, which is associated with increasing BMI, appeared to increase the risk of liver fibrosis.     

Steatosis in chronic hepatitis C: relationship to the virus and host risk factors

Background: Steatosis occurs frequently in hepatitis C. However, the mechanisms leading to this lesion are still unknown, and the role of steatosis in the progression of the disease remains controversial. The aim of the present paper was to determine the prevalence of steatosis in hepatitis C and its association with hepatitis C virus (HCV) genotype, viral load and the presence of risk factors for steatosis, and to analyze the association between steatosis and the intensity of liver disease. Methods: Patients infected with HCV who underwent liver biopsy were included. Patients coinfected with hepatitis B virus and/or human immunodeficiency virus and those previously treated for hepatitis C were excluded. The following risk factors for steatosis were investigated: obesity (body mass index [BMI] > 25 kg/m²), diabetes mellitus, hyperlipidemia, alcoholism, and use of potential steatosis‐inducing drugs. Histological analysis evaluated the presence of steatosis, the degree of periportal activity and staging. Patients with and without steatosis were compared regarding demographic, epidemiological, laboratory and histological characteristics. Logistic regression analysis was applied to identify variables that were independently associated with the presence of steatosis. Results: Ninety patients (55 men, 35 women) with a mean age of 45 ± 13 years were included. The prevalence of steatosis was 67%. Variables that remained independently associated with steatosis were age, female gender, obesity and genotype 3. Conclusions: The prevalence of steatosis in hepatitis C was high. Risk factors usually related to steatosis such as age, female gender and obesity, as well as genotype 3, were independently associated with the presence of steatosis. Steatosis was not independently associated with the intensity of histological liver disease.     

Prevalence and risk factors of hepatic steatosis and its impact on liver injury in Chinese patients with chronic hepatitis B infection

Background and Aims:  The clinical significance of hepatic steatosis in chronic hepatitis B infection (CHB) is unclear. The aims of this study were thus to investigate the prevalence and risk factors for hepatic steatosis in patients with CHB and its relationship with liver injury.
Methods:  Consecutive patients with biopsy-proven CHB at Hangzhou Sixth People's Hospital between January 2005 and June 2007 were included. Patients co-infected with other viruses or suffering from liver disease of any other cause were excluded. Liver steatosis, necroinflammation and fibrosis were assessed by both Brunt and Scheuer classifications.
Results:  A total of 1915 patients (1497 men) with a mean age of 31 ± 9.5 years were analyzed. Hepatic steatosis was present in 260 (14%) patients. The steatosis involved < 33% of hepatocytes in 90% of cases, and was more frequent among men than women (15% vs 8%, P  < 0.001). Two-thirds (178 of 260) of patients with steatosis were hepatitis B e antigen (HBeAg)-positive, but there was no correlation with either serum HBeAg status or hepatitis B virus DNA titer. Degree of inflammation and fibrosis were more mild among those with steatosis than those without. Multivariate analysis showed that steatosis was independently associated with body mass index, serum triglyceride, apolipoprotein B, uric acid, and fasting blood glucose. However, fibrosis was only independently associated with age and inflammatory grade, and the latter associated with viral load and fibrosis stage.
Conclusions:  Hepatic steatosis is common in CHB, it is associated with metabolic factors not viral ones, and does not appear to affect the severity of liver disease.     

Non-alcoholic fatty liver disease in Malaysia: a demographic, anthropometric, metabolic and histological study

BACKGROUND AND OBJECTIVES: Nonalcoholic fatty liver disease (NAFLD) is increasing rapidly in the Asia–Pacific region. There has been a paucity of studies from the region. The aims of this study were to define the demographic, anthropometric, metabolic and histological characteristics of patients with NAFLD in our local population and to determine independent predictors of severe liver fibrosis. METHODS: Patients with persistently raised liver enzymes and/or fatty liver detected on ultrasonography with exclusion of other liver disorders were prospectively recruited. Their insulin resistance was assessed using the homeostasis model assessment of insulin resistance score. A liver biopsy was performed in all cases for grading (for steatohepatitis) and staging (for fibrosis) of NAFLD. Independent risk factors for fibrosis were determined using multiple logistic regression analysis. RESULTS: Seventy‐five patients were recruited: 39 men (52%) and 36 women (48%). The mean age of the patients was 47.0 ± 12.2 years. Of these, 58 patients (77.3%) were centrally obese, 29 patients (38.7%) were diabetic and 15 patients (20.0%) had impaired glucose tolerance. Insulin resistance was diagnosed in 62 out of 64 (96.9%) patients. Benign steatosis, nonalcoholic steatohepatitis and cirrhosis were diagnosed in three (4.3%), 59 (84.3%) and eight (11.4%) of 70 patients, respectively. Significant independent predictors of liver fibrosis were; male sex (P = 0.019, OR = 5.55, CI = 1.33–23.18) and Indian race (P = 0.013, OR = 8.21, CI = 1.56–43.16). CONCLUSIONS: The full histological spectrum of NAFLD was seen in our patients. The majority of patients were insulin resistant, centrally obese and either diabetic or had impaired glucose tolerance. The predictors of severe liver fibrosis were male sex and Indian race.     

Clinicopathological study of nonalcoholic fatty liver disease in Japan: the risk factors for fibrosis

Background/Aims: We evaluated patients with nonalcoholic fatty liver disease (NAFLD) and compared the clinical and pathological features to identify the risk factors for NAFLD with severe fibrosis. Methods: One hundred and eighty‐two patients with biopsy‐confirmed NAFLD from various medical centres were recruited into this study. Results: The variables that were significantly associated with severe steatosis were male gender (mild:severe=36%:53%, P=0.02), younger age (mild:severe=57%:82%, P>0.001) and absence of type 2 diabetes (mild:severe=43%:71%, P>0.001). There was no significant difference in the degree of inflammation among the clinical groups. The variables that were significantly associated with severe fibrosis were female gender (mild:severe=54%:84%, P=0.002), older age (≥60 years old) (mild:severe=29%:53%, P=0.020), type 2 diabetes (mild:severe=42%:71%, P=0.020) and hypertension (mild:severe=24%:53%, P=0.002). Although there were more obese patients in the group with severe fibrosis, the association was not statistically significant (mild:severe=67%:78%, P=0.229). The prevalence of high serum triglyceride levels was similar between the two groups. The N (Nippon) score (total number of risk factor) could significantly predict severe fibrosis in NAFLD patients (1.48 ± 1.14 vs. 2.66 ± 0.94, P<0.001). Conclusions: The N score can be used to predict severe fibrosis in cases of NAFLD.     

Liver function and morphology during long-term fatty acid supplementation in cystic fibrosis

Abstract: Liver function tests and liver morphology were studied in 18 patients with cystic fibrosis (CF) for a period of 3 years. The patients were 5–19 years of age at the start of the study. Nine patients received regular supplementation of essential fatty acids (Intralipid®) and nine sex- and age-matched patients, with as similar clinical status as possible but without fat emulsion treatment, were followed as controls. There were no significant differences between the two groups with regard to the parameters of liver function, including determinations of bile acids in serum and urine. Histological examinations of liver biopsies suggested less progression of liver disease in the fatty acid supplemented group, including fatty infiltration of the hepatocytes, evaluated morphometrically. The results show that regular supplementation of fat emulsions has no negative effects in the liver of patients with CF, and the lessening of progression of liver damage suggests that essential fatty acid deficiency might contribute to the liver damage in this disease.     

老年人群非酒精性脂肪性肝病的危险因素分析

目的探讨老年患者非酒精性脂肪性肝病(NAFLD)的危险因素。方法选择2013年1月至11月在上海交通大学医学院附属新华医院行颅脑磁共振和腹部超声检查的481例住院患者,其中年龄≥65岁250例,NAFLD患者225例,≥65岁NAFLD患者108例。通过生化指标、颈部血管超声等检测,分析老年NAFLD患者的危险因素。结果老年人群2型糖尿病、高血压病、心房颤动、急性脑梗死和既往脑梗死的患病率以及颈动脉斑块、颈动脉狭窄的阳性率显著升高,而NAFLD患病率则显著降低(P0.05)。≥65岁NAFLD组急性脑梗死、2型糖尿病、心房颤动患病率以及存在颈动脉斑块和有既往脑梗死史的患者比例较年龄65岁组显著升高(P0.05);≥65岁NAFLD组BMI、24 h平均收缩压和舒张压、HbA1c、三酰甘油、空腹及餐后两小时血糖水平较对照组显著升高(P0.05);多因素Logistic回归分析显示急性脑梗死与老年人群NAFLD关系密切(OR=3.055,95%CI1.132-8.24)。结论≥65岁组NAFLD患病率较年龄65岁组显著下降;急性脑梗死与老年人群NAFLD独立相关。     

Melatonin and circadian rhythms in liver diseases: Functional roles and potential therapies

Circadian rhythms and clock gene expressions are regulated by the suprachiasmatic nucleus in the hypothalamus, and melatonin is produced in the pineal gland. Although the brain detects the light through retinas and regulates rhythms and melatonin secretion throughout the body, the liver has independent circadian rhythms and expressions as well as melatonin production. Previous studies indicate the association between circadian rhythms with various liver diseases, and disruption of rhythms or clock gene expression may promote liver steatosis, inflammation, or cancer development. It is well known that melatonin has strong antioxidant effects. Alcohol drinking or excess fatty acid accumulation produces reactive oxygen species and oxidative stress in the liver leading to liver injuries. Melatonin administration protects these oxidative stress-induced liver damage and improves liver conditions. Recent studies have demonstrated that melatonin administration is not limited to antioxidant effects and it has various other effects contributing to the management of liver conditions. Accumulating evidence suggests that restoring circadian rhythms or expressions as well as melatonin supplementation may be promising therapeutic strategies for liver diseases. This review summarizes recent findings for the functional roles and therapeutic potentials of circadian rhythms and melatonin in liver diseases.     

Histopathological evaluation of fatty and alcoholic liver diseases

Fatty liver disease (FLD) represents a common form of hepatic dysfunction among adults and children. Recognition of steatosis is usually straightforward but the differential diagnosis is broad. Macrovesicular steatosis may occur due to alcohol use or metabolic factors including obesity and hyperinsulinemia. Steatosis is, in some patients, accompanied by varying degrees of inflammation, ballooning hepatocyte degeneration or fibrosis, or both. The pathologist's recognition and interpretation of these features, when present, is critical for the classification and prognostication of the disease. Recent advances in the study of FLD have yielded new information for the surgical pathologist to guide the interpretation of steatosis in children and adults, and in patients with other forms of liver disease such as chronic viral hepatitis. This article details the current terminology for various forms of FLD, highlights the key histological features and reviews recent advances in the field.     

多囊卵巢综合征患者非酒精性脂肪性肝病的发病情况及特点分析

目的探讨多囊卵巢综合征（PCOS）患者非酒精性脂肪性肝病（NAFLD）的发生情况和临床特点。方法对306例PCOS患者行基础内分泌、口服糖耐量试验及胰岛素释放试验、肝功、血脂、肝脏超声等检查。分析NAFLD的发病情况及特点。结果 NAFLD发生率为30.7%（94/306）;NAFLD发病率随体质量指数（BMI）和年龄的增加而升高。PCOS合并NAFLD者空腹血糖、空腹胰岛素、口服葡萄糖2h后血糖及胰岛素水平、稳态模型评估（HOMA-IR）、谷丙转氨酶（ALT）、谷草转氨酶（AST）、TC、TG、LDL-C、BMI、腰围、腰臀比,均显著高于不合并NAFLD者（P均〈0.05）;而量化胰岛素敏感指数（QUICK）、HDL-C则显著低于不合并NAFLD者（P均〈0.05）。PCOS合并NAFLD者胰岛素抵抗、腹型肥胖、糖耐量异常、糖尿病、肝功异常、血脂异常、高血压病及代谢综合征的患病率显著高于不合并NAFLD者（P〈0.05）。结论 PCOS伴NAFLD发病率较高;其发病率与BMI和年龄呈正相关;PCOS伴NAFLD多存在胰岛素抵抗、代谢异常;超重及腹型肥胖是PCOS患者NAFLD的主要危险因素。     

Genetic variants in the MTHFR are not associated with fatty liver disease

The common missense sequence variants of methylenetetrahydrofolate reductase (MTHFR), rs1801131 (c.A1298C) and rs1801133 (c.C677T), favour the development of hyperhomocysteinemia and diminished DNA methylation. Previous studies, carried out in small series and with suboptimal characterization of the hepatic phenotype, tested the association of these genetic variants with fatty liver disease (FLD), with conflicting results. Here, we assessed the association of rs1801131 and rs1801133 with hepatic phenotype in the Liver Biopsy Cross‐Sectional Cohort, a large cohort (n=1375 from Italy and 411 from Finland) of European individuals with suspect FLD associated with dysmetabolism. A total of 1786 subjects were analysed by ordinal regression analyses. The rs1801131 and the rs1801133 variants were not associated with steatosis, inflammation, ballooning or fibrosis. The present study suggests that changes in folate and methionine metabolism resulting from these 2 variants are not associated with a clinically significant impact on FLD in Europeans.     

Nonalcoholic Fatty Liver Disease: Noninvasive Methods of Diagnosing Hepatic Steatosis

Hepatic steatosis is the buildup of lipids within hepatocytes. It is the simplest stage in nonalcoholic fatty liver disease (NAFLD). It occurs in approximately 30% of the general population and as much as 90% of the obese population in the United States. It may progress to nonalcoholic steatohepatitis, which is a state of hepatocellular inflammation and damage in response to the accumulated fat. Liver biopsy remains the gold standard tool to diagnose and stage NAFLD. However, it comes with the risk of complications ranging from simple pain to life-threatening bleeding. It is also associated with sampling error. For these reasons, a variety of noninvasive radiological markers, including ultrasound, computed tomography, magnetic resonance spectroscopy, and the controlled attenuation parameter using transient elastography and Xenon-133 scan have been proposed to increase our ability to diagnose NAFLD, hence avoiding liver biopsy. The aim of this review is to discuss the utility and accuracy of using available noninvasive diagnostic modalities for fatty liver in NAFLD.     

Hepatic steatosis in hepatitis B virus infected patients: meta-analysis of risk factors and comparison with hepatitis C infected patients

Background and Aims: Although hepatic steatosis (HS) has an association with hepatitis C virus (HCV) infection, an association with hepatitis B virus (HBV) is controversial. We performed a meta‐analysis to evaluate HS prevalence and risk factors, in HBV infection. Methods: Standard guidelines for performance of meta‐analyses were followed. Studies with HS assessed by histology were included. Pooled odd ratios (OR) and standardized mean differences (SMD) were obtained with the random‐effects model and DerSimonian‐Laid method. Results: Seventeen out of 21 studies were included, comprising 4100 HBV infected patients. Overall HS prevalence was 29.6%. Eight studies also included 945 HCV infected patients, showing decreased risk of HS in HBV versus HCV patients (OR 0.55, 95%CI [0.45–0.67], P < 0.001). In HBV, HS positively associated with male gender (OR 1.74, 95%CI [1.28–2.38], P < 0.001), body mass index (SMD 2.17, 95%CI [1.23, 3.11], P < 0.001), obesity (OR 6.59, 95%CI [3.51–12.257], P = 0.003), diabetes (OR 2.62, 95%CI [1.37–4.00], P = 0.004), glycemia (SMD 0.84, 95%CI [0.00, 1.67], P = 0.049), triglycerides (SMD 1.18, 95%CI [0.48, 1.89], P = 0.001), cholesterol (SMD 0.88, 95%CI [0.31, 1.45], P = 0.003), moderate alcohol consumption (OR 1.54, 95%CI [1.10–2.15], P = 0.011) and negatively with HBV DNA (SMD ?74.12, 95%CI [?82.93, ?65.31], P < 0.001). HS had no association with aminotransferases, HBeAg, genotype or hepatic histology, necroinflammation or fibrosis. Conclusion: HS in HBV seems to be as frequent as in the general population, and lower than in HCV infected patients, relating to metabolic factors but not with hepatic histology severity. A puzzling strong negative association between viral load and HS, may even suggest a protective effect of the virus on HS.     

Acetaminophen‐induced liver injury in obesity and nonalcoholic fatty liver disease

Although acetaminophen (APAP) is usually considered as a safe drug, this painkiller can lead to acute liver failure after overdoses. Moreover, there is evidence that the maximum recommended dosage can induce hepatic cytolysis in some individuals. Several predisposing factors appear to enhance the risk and severity of APAP‐induced liver injury including chronic alcoholic liver disease and nonalcoholic fatty liver disease (NAFLD), which refers to a large spectrum of hepatic lesions linked to obesity. In contrast, obesity by itself does not seem to be associated with a higher risk of APAP‐induced liver injury. Since 1987, seven studies dealt with APAP‐induced hepatotoxicity in rodent models of NAFLD and five of them found that this liver disease was associated with higher APAP toxicity. Unfortunately, these studies did not unequivocally established the mechanism(s) whereby NAFLD could favour APAP hepatotoxicity, although some investigations suggested that pre‐existent induction of hepatic cytochrome P450 2E1 (CYP2E1) could play a significant role by increasing the generation of N‐acetyl‐p‐benzoquinone imine (NAPQI), the toxic metabolite of APAP. Moreover, pre‐existent mitochondrial dysfunction associated with NAFLD could also be involved. In contrast, some investigations suggested that factors that could reduce the risk and severity of APAP hepatotoxicity in obesity and NAFLD include higher hepatic APAP glucuronidation, reduced CYP3A4 activity and increased volume of body distribution. Thus, the occurrence and the outcome of APAP‐induced liver injury in an obese individual with NAFLD might depend on a delicate balance between metabolic factors that can be protective and others that favour large hepatic levels of NAPQI.     

Validation of the Fatty Liver Index for identifying non-alcoholic fatty liver disease in a Kenyan population

Background and Aim

Fatty Liver Index (FLI) is a simple clinical scoring system estimating non-alcoholic fatty liver disease (NAFLD). It is validated in European-descent and Asian populations, but not in sub-Saharan Africans. The aim of this study is to evaluate the validity of the FLI for predicting NAFLD in a population from Kenya.

Methods

Participants were recruited from a community-based study conducted in Kenya. NAFLD was diagnosed using hepatic ultrasonography. Clinical, anthropometrical, biochemical and lifestyle data were obtained. The accuracy and cut-off point of the FLI to detect NAFLD were evaluated by area under the receiver operator characteristic curve and the maximum Youden index analysis.

Results

A total of 640 participants (94 with NAFLD) were included. Mean age was 37.4 ± 0.4 years and 58.7% were women. Mean body mass index (BMI) was 22.3 ± 0.2 kg/m² and waist circumference (WC) 79.1 ± 0.4 cm. A total of 15 (2.3%) participants were diagnosed with type 2 diabetes and 65 (10.2%) with obesity (BMI ≥ 30 kg/m²). AUROC of FLI for predicting NAFLD was 0.80 (95% CI 0.74–0.85), which was significantly higher compared to individual components gamma-glutamyl transferase and triglycerides (p < 0.05), but not compared to anthropometric parameters BMI (AUROC of 0.83, 95% CI 0.79–0.88) and WC (AUROC of 0.81, 95% CI 0.76–0.87).

Conclusions

FLI is a simple valid scoring system to use in rural and urban Kenyan adults. However, this index might not be superior to BMI or WC to predict NAFLD, and those measurements might therefore be more appropriate in limited settings.