The importance of metabolic factors for the increasing prevalence of fatty liver in Shanghai factory workers

Impact of metabolic disorders on gallstone disease and perioperative recovery after laparoscopic cholecystectomy

BACKGROUND

Gallstone disease (GSD), nonalcoholic fatty liver disease (NAFLD), metabolic dysfunction-associated fatty liver disease (MAFLD), and metabolic syndrome (MetS) are common medical disorders worldwide. This study aimed to ascertain how NAFLD, MAFLD, MetS, and other factors affect the development of GSD, and how the GSD-associated factors influence patient recovery after laparoscopic cholecystectomy (LC).

METHODS

We included 200 patients who were diagnosed with GSD and underwent LC between January 2017 and February 2022. A total of 200 subjects without GSD and "non-calculous causes" during the same period were also included as controls. We compared the metabolic disorder differences between GSD patients and controls. Furthermore, we sub-grouped patients based on the comorbidities of preoperative NAFLD, MAFLD, and MetS, and compared the impacts of these comorbidities on short-term post-LC functional recovery of the patients.

RESULTS

The prevalence of NAFLD and MetS were higher in GSD patients (P < 0.05). Based on multivariate logistic regression analysis, hyperglycemia [odds ratio (OR) = 2.2, 95% confidence interval (CI): 1.4-3.4, P = 0.001] and low high-density lipoprotein cholesterol (HDL-C) level (OR = 1.8, 95% CI: 1.1-3.1, P = 0.048) were linked to GSD. NAFLD and MetS linked to liver enzymes after LC (P < 0.05). MetS also linked to the levels of inflammatory indicators after LC (P < 0.05). The obesity, hyperlipidemia, low HDL-C level, and hyperglycemia linked to liver enzymes after LC (P < 0.05). Hyperlipidemia, low HDL-C level, and hypertension linked to inflammation after LC (P < 0.05).

CONCLUSIONS

The prevalence of GSD may be linked to NAFLD and MetS. Hyperglycemia and low HDL-C level were independent risk factors of GSD.

Plasma Heparin Cofactor II Activity Is Inversely Associated with Hepatic Fibrosis of Non-Alcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Mellitus

AIMS

Thrombin exerts various pathophysiological functions by activating protease-activated receptors (PARs), and thrombin-induced activation of PARs promotes the development of non-alcoholic fatty liver disease (NAFLD). Since heparin cofactor II (HCII) specifically inactivates thrombin action, we hypothesized that plasma HCII activity correlates with the severity of NAFLD.

METHODS

A cross-sectional study was conducted. Plasma HCII activity and noninvasive clinical markers of hepatic fibrosis including fibrosis-4 (FIB-4) index, NAFLD fibrosis score (NFS) and aspartate aminotransferase-to-platelet ratio index (APRI) were determined in 305 Japanese patients with type 2 diabetes mellitus (T2DM). The relationships between plasma HCII activity and the clinical markers were statistically evaluated.

RESULTS

Multiple regression analysis including confounding factors showed that plasma HCII activity independently contributed to decreases in FIB-4 index (p＜0.001), NFS (p＜0.001) and APRI (p=0.004). In addition, logistic regression analysis for the prevalence of advanced hepatic fibrosis defined by the cutoff points of the clinical scores showed that plasma HCII activity was the sole and common negative factor for prevalence of advanced hepatic fibrosis (FIB-4 index: p=0.002, NFS: p=0.026 and APRI: p=0.012).

CONCLUSIONS

Plasma HCII activity was inversely associated with clinical hepatic fibrosis indices including FIB-4 index, NFS and APRI and with the prevalence of advanced hepatic fibrosis in patients with T2DM. The results suggest that HCII can serve as a novel biomarker for assessment of hepatic fibrosis of NAFLD in patients with T2DM.

Pin1 Plays Essential Roles in NASH Development by Modulating Multiple Target Proteins

Pin1 is one of the three known prolyl-isomerase types and its hepatic expression level is markedly enhanced in the obese state. Pin1 plays critical roles in favoring the exacerbation of both lipid accumulation and fibrotic change accompanying inflammation. Indeed, Pin1-deficient mice are highly resistant to non-alcoholic steatohepatitis (NASH) development by either a high-fat diet or methionine-choline-deficient diet feeding. The processes of NASH development can basically be separated into lipid accumulation and subsequent fibrotic change with inflammation. In this review, we outline the molecular mechanisms by which increased Pin1 promotes both of these phases of NASH. The target proteins of Pin1 involved in lipid accumulation include insulin receptor substrate 1 (IRS-1), AMP-activated protein kinase (AMPK) and acetyl CoA carboxylase 1 (ACC1), while the p60 of the NF-kB complex and transforming growth factor β (TGF-β) pathway appear to be involved in the fibrotic process accelerated by Pin1. Interestingly, Pin1 deficiency does not cause abnormalities in liver size, appearance or function. Therefore, we consider the inhibition of increased Pin1 to be a promising approach to treating NASH and preventing hepatic fibrosis.

Low muscle mass and low muscle strength associate with nonalcoholic fatty liver disease

BACKGROUND

It is unclear whether low muscle mass and low muscle strength are independently or jointly associated with nonalcoholic fatty liver disease (NAFLD). Hence, the aim of the present study was to investigate the associations of NAFLD with low muscle mass, low muscle strength, sarcopenia, and sarcopenic obesity.

METHODS

A total of 5132 participants aged 18-80 years were recruited in this cross-sectional study. NAFLD was diagnosed using ultrasound. Muscle mass was evaluated using skeletal muscle mass index and muscle strength was evaluated using weight-adjusted hand grip strength. Sarcopenia was defined as the presence of both low muscle mass and low muscle strength. Sarcopenic obesity was defined as the presence of both sarcopenia and obesity. Multivariate logistic regression models were used to explore the associations of NAFLD with low muscle mass, low muscle strength, sarcopenia, and sarcopenic obesity.

RESULTS

Low muscle mass and low muscle strength were positively and independently associated with NAFLD (mass: odds ratio [OR], 2.57; 95% confidence interval [CI], 2.03-3.25; strength: OR, 1.47; 95% CI, 1.21-1.80). Compared with low muscle mass or low muscle strength alone, sarcopenia was associated with a higher risk of NAFLD (OR, 3.91; 95% CI, 2.90-5.28). Whether obesity was defined by body mass index (BMI) or waist circumference (WC), sarcopenic obesity was associated with a higher risk of NAFLD (BMI: OR, 10.42; 95% CI, 7.14-15.22; WC: OR, 11.64; 95% CI, 8.22-16.48) than sarcopenia or obesity alone.

CONCLUSIONS

Low muscle mass and low muscle strength were positively and independently associated with NAFLD. When both were presented in the sarcopenic state, the risk of NAFLD was higher, and a concurrence of sarcopenia and obesity showed the highest risk of NAFLD.

Prevalence and risk factors of sonographically detected non alcoholic fatty liver disease in a screening centre in Klang Valley, Malaysia: an observational cross-sectional study

Objectives:

Nonalcoholic fatty liver disease (NAFLD) is a very common liver disorder in Western countries. As of late, it has been found to be prevalent in Asia as well. It is a benign disease unless it develops into necroinflammation and fibrosis. This study was proposed to determine the prevalence and risk factors of sonography-detected NAFLD among Malaysian adults in Klang Valley, West Malaysia.

Study design:

An observational cross-sectional study.

Methods:

The participants were aged between 45 and 75 years who participated in a screening program at the Golden Horses Health Sanctuary in Klang Valley. Lipid profile and anthropometric measurements were collected from the subjects’ medical records. Ultrasound machine and a structured self-administered questionnaire were used as instruments for recruiting data from the subjects. The subjects who consumed alcohol (>140 g/wk for men and >70 g/wk for females), had hepatitis B or C viruses, liver insults, and surgery, and taken lipid-lowering medications were excluded from the study.

Results:

A total of 628 subjects were analyzed, and 235 (37.4%) subjects were diagnosed with definite NAFLD. They comprised 518 (82.5%) Chinese, 92 (14.6%) Malays, and 18 (2.9%) Indians. Peak prevalence of NAFLD was found in 53 to 60 years age group. The higher prevalence of NAFLD was among men (48.3%) than women (27.3%) and among Indians (61.1%) and Malays (51.1%) than among Chinese (34.2%). NAFLD has been found to be strongly correlated with male sex, high body mass index (≥23.0 kg/m²), hypertriglyceridemia, low high-density lipoprotein cholesterol, diabetes mellitus, and hypertension.

Conclusion:

NAFLD is quite common among adults in Malaysian urban population. The prevalence of NAFLD was inordinately high among the 53 to 60 years age group, male sex, Indians, and Malays (as compared with Chinese). Age >60 years, male sex, high body mass index (≥23.0 kg/m²), hypertriglyceridemia, and diabetes mellitus were proven to be risk predictors for NAFLD.

Epidemiology and natural history of non-alcoholic fatty liver disease

Non-alcoholic steatohepatitis (NASH) is part of the spectrum of non-alcoholic fatty liver disease (NAFLD) that leads to progressive liver disease and presents a growing challenge to public health. Because of the increased prevalence of metabolic syndrome and obesity, NAFLD and NASH have expanded to a substantial extent. In NASH patients, advanced fibrosis is the major predictor of morbidity and liver-related mortality, and an accurate diagnosis of NASH is mandatory. Although there is currently no validated test of serum biomarkers available to diagnose NASH, and histologic evaluation with a liver biopsy remains the gold standard, screening for fibrosis is recommended in patients with suspicion of NASH. Clinical prediction models and serum biomarkers for advanced fibrosis have relatively good negative predictive value and can be useful for screening. Also, transient elastography is increasingly available to estimate fibrosis in NASH. Therefore, due to the lack of a reliable and accepted non-invasive diagnostic modality, screening for NASH in the general population is not currently recommended. Better understanding of the natural history of NASH is needed to evaluate the utility and cost-effectiveness of screening.

Sex hormone affects the severity of non-alcoholic steatohepatitis through the MyD88-dependent IL-6 signaling pathway

Recent research has shown that the occurrence of gender disparity in liver cancer associated with sex differences in MyD88-dependent IL-6 production, but the role of this signaling pathway in sex differences of non-alcoholic steatohepatitis (NASH) remains unknown. To investigate the effects of sex hormone-specific intervention on pathology and progression of NASH, and on the inflammatory TLR-MyD88-IL-6 signaling pathway NASH was modeled in C57/BL6 mice by feeding a methionine and choline-deficient (MCD) diet for 4 weeks. Male mice were subjected to sex hormone-related interventions such as orchidectomy, and orchidectomy combined with administration of either testosterone propionate or estradiol benzoate. Next, the degree of non-alcoholic fatty liver disease activity score (NAS), serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and the expression level of MyD88 and IL-6, were compared between these groups. Males developed more serious inflammatory problems and had a higher NAS than the females. Sex-specific intervention in male mice by orchidectomy reduced NAS, ALT, and AST, and the expression level of MyD88 and IL-6. But administration of exogenous androgen had no influence on either NAS or the expression of ALT, AST, MyD88, and IL-6. On the other hand, exogenous estrogen could alleviate the pathological damage caused by NASH, as well as reduce NAS, ALT and AST, and the expression of MyD88 and IL-6. The result show different sex hormone-related interventions affected the severity of NASH, possibly by modulating the level of sex hormones and regulating the TLR-MyD88-IL-6 signaling pathway.

The clinical investigation of disparity of nonalcoholic fatty liver disease in a Chinese occupational population in Taipei, Taiwan: experience at a teaching hospital

The authors sought to explore the prevalence and factors related to nonalcoholic fatty liver disease (NAFLD) among occupational population in Taipei, Taiwan. A total of 8347 healthy adults voluntarily admitted to annual physical check-up. Blood samples and ultrasound-proved fatty liver sonography results were collected. The results showed that the prevalence of NAFLD was 48.4% and revealed a statistically significant increase with increasing population age. Males exhibited a greater prevalence of NAFLD than did females (57.8% vs 32.4%, P < .001). Using multiple logistic regression analysis, in addition to male gender, older age, higher body mass index, higher aspartate aminotransferase level, higher alanine aminotransferase level, presence of hypertension, presence of hyperuricemia, presence of hypercholesterolemia, higher fasting plasma glucose, and presence of hypertriglyceridemia were the significant factors associated with NAFLD. The differences in occupational professions were revealed. In conclusion, occupational populations are asymptomatic, and the diagnosis of NAFLD should be considered with older age, hyperuricemia, higher aspartate aminotransferase level, higher alanine aminotransferase level, and metabolic risk factors.

A systematic review of the prevalence of mildly abnormal liver function tests and associated health outcomes

Liver function tests (LFTs) are commonly performed to investigate asymptomatic individuals or those with nonspecific symptoms. Understanding the prevalence of mildly abnormal LFTs in the general population and the prevalence of liver disease following abnormal LFTs has important implications for the planning of care pathways and the provision of healthcare services. A systematic review of the literature on the prevalence of abnormal LFTs in the general population and their respective health outcomes was conducted. A total of 37 studies reporting data on the prevalence of abnormal LFTs (published between 2000 and 2014) were identified from online database searches or were manually selected from article bibliographies. The prevalence of mildly abnormal LFTs, with one or more abnormal constituents in the LFT, was high at 10-21.7%. The prevalence of severe liver disease within cohorts with abnormal LFTs is relatively low (<5%), and a large proportion of abnormal LFTs remains unexplained. Among individuals with unexplained abnormal LFTs, risk factors include obesity and insulin resistance. Common aetiologies for abnormal LFTs were non-alcohol-related fatty liver disease (NAFLD), followed by alcohol use and viral infections. In addition, normal LFTs do not rule out liver disease. The prevalence of abnormal LFTs depends on the definition and population but is likely to be between 10 and 20% in the general population. Abnormal LFTs are associated with a range of health outcomes but are not necessarily strongly diagnostic of severe liver pathology. Important areas of future research include further studies on the prevalence and predictive ability of LFTs in large, population-representative samples.

Vitamin E has a beneficial effect on nonalcoholic fatty liver disease: a meta-analysis of randomized controlled trials

OBJECTIVES

Vitamin E is often used in the treatment of nonalcoholic fatty liver disease (NAFLD), including nonalcoholic steatohepatitis (NASH); however, the magnitude of treatment response associated with vitamin E in improving liver function and histology in NAFLD/NASH has not, to our knowledge, been quantified systematically. Thus, we conducted a meta-analysis of randomized controlled trials (RCTs) using vitamin E in the treatment of NAFLD/NASH.

METHODS

PubMed, Medline, and Cochrane Library Full Text Database, and Japan Medical-Literature Database (Igaku Chuo Zasshi) were searched until March 2014, and five RCTs were identified for meta-analysis.

RESULTS

According to a random effect model analysis of the five studies, vitamin E significantly reduced aspartate transaminase (AST) by -19.43 U/L, alanine aminotransferase (ALT) by -28.91 U/L, alkaline phosphatase (ALP) by -10.39 U/L, steatosis by -0.54 U/L, inflammation by -0.20 U/L, and hepatocellular ballooning by -0.34 U/L compared with the control group. Vitamin E treatment with NASH adult patients showed obvious reductions in not only AST of -13.91 U/L, ALT by -22.44 U/L, steatosis of -0.67 U/L, inflammation of -0.20 U/L, but also fibrosis of -0.30 U/L compared to the control treatment.

CONCLUSIONS

Vitamin E significantly improved liver function and histologic changes in patients with NAFLD/NASH.

Hemoglobin combined with triglyceride and ferritin in predicting non-alcoholic fatty liver

BACKGROUND AND AIM

The red blood cells (RBC) count is closely associated with insulin resistance (IR), which is origin of non-alcoholic fatty liver disease (NAFLD). This study aimed to investigate the correlation of RBC indices with NAFLD.

METHODS

A total of 977 cases including 446 NAFLD patients and 531 controls were enrolled and examined for biochemical and metabolic indices. RBC, hematocrit (HCT), hemoglobin (HGB), insulin, and ferritin were detected. The IR indicator latest homeostasis model assessment-insulin resistance and fatty liver index were calculated. The correlation analysis was assessed by Spearman's rank test. Receiver operating characteristic was used to evaluate diagnostic performance. After quartile classification of RBC indices, logistic regression analysis was conducted to evaluate the odds ratios (OR) of NAFLD.

RESULTS

RBC, HCT, and HGB levels were obviously higher in NAFLD group. RBC, HCT, and HGB showed significant positive correlation with homeostasis model assessment-insulin resistance and NAFLD. Multivariate analysis revealed HGB, ferritin, and triglyceride (TG) as independent parameters associated with NAFLD. The predictive value after combination of HGB with ferritin and TG was equal to fatty liver index. After adjustment for age,body mass index, systolic blood pressure, total cholesterol, TG, low-density lipoprotein, high-density lipoprotein and smoking, comparing the groups with the highest and lowest HGB, HCT, and RBC, the OR (95% confidence intervals) of NAFLD were 2.369 (1.279-4.368) (P < 0.05), 1.504 (0.819-2.713) (P > 0.05), and 2.332 (0.823-2.550) (P > 0.05) in men. In women, the OR were 2.541 (1.118-5.771), 3.578 (1.464-8.748), and 3.215 (1.387-7.455) (P < 0.05).

CONCLUSIONS

Our data suggest that HGB combined with TG and ferritin may serve as the indicator of predicting NAFLD.

Clinical predictors of incident gallstone disease in a Chinese population in Taipei, Taiwan

BACKGROUND

Gallstone disease (GSD) is a common gastrointestinal disorder throughout the world. The authors explored the incidence of GSD in Taiwan and its condition-associated predictive factors.

METHODS

The initial study cohort comprised 2386 healthy adult participants, who were voluntarily admitted to a teaching hospital for a physical check-up in 2002 in Taipei, Taiwan. After excluding 126 patients who exhibited prevalent GSD, 2260 non-GSD participants received annual follow-up screenings for GSD until 31 December, 2007. Of those, 1296 (57.3%) patients were re-examined to collect blood samples and conduct ultrasound sonography.

RESULTS

Among the 1296 participants who exhibited no GSD at the first screening, 23 patients developed GSD during 3640 person-years of follow-up. The incidence was 0.632% per year (95% CI: 0.292%-2.009%). After conducting a Cox regression, increased age (50-59 years versus < 40 years, RR = 2.16 [95% CI: 1.09-5.97], 60+ years versus < 40 years, RR = 3.81 [95% CI: 2.77-8.63]), high body mass index (≥27 kg/m2 versus < 24 kg/m2, RR = 1.64 [95% CI: 1.07-2.98]), high fasting plasma glucose levels (≥126 mg/dL versus < 110 mg/dL, RR = 1.68, 95% CI: 1.10-3.87), and nonalcoholic fatty liver disease (yes versus no, RR = 1.44, 95% CI: 1.21-1.90) appeared to be significantly related to developing GSD.

CONCLUSION

Increased age is a well-established risk factor for developing GSD. The current findings indicated that high body mass index, elevated fasting plasma glucose levels, and nonalcoholic fatty liver disease were also associated with GSD.

Association of adult weight gain and nonalcoholic fatty liver in a cross-sectional study in Wan Song Community, China

Our objective was to examine associations of adult weight gain and nonalcoholic fatty liver disease (NAFLD). Cross-sectional interview data from 844 residents in Wan Song Community from October 2009 to April 2010 were analyzed in multivariate logistic regression models to examine odds ratios (OR) and 95% confidence intervals (CI) between NAFLD and weight change from age 20. Questionnaires, physical examinations, laboratory examinations, and ultrasonographic examination of the liver were carried out. Maximum rate of weight gain, body mass index, waist circumference, waist-to-hip ratio, systolic blood pressure, diastolic blood pressure, fasting blood glucose, cholesterol, triglycerides, uric acid, and alanine transaminase were higher in the NAFLD group than in the control group. HDL-C in the NAFLD group was lower than in the control group. As weight gain increased (measured as the difference between current weight and weight at age 20 years), the OR of NAFLD increased in multivariate models. NAFLD OR rose with increasing weight gain as follows: OR (95%CI) for NAFLD associated with weight gain of 20+ kg compared to stable weight (change <5 kg) was 4.23 (2.49-7.09). Significantly increased NAFLD OR were observed even for weight gains of 5-9.9 kg. For the "age 20 to highest lifetime weight" metric, the OR of NAFLD also increased as weight gain increased. For the "age 20 to highest lifetime weight" metric and the "age 20 to current weight" metric, insulin resistance index (HOMA-IR) increased as weight gain increased (P<0.001). In a stepwise multivariate regression analysis, significant association was observed between adult weight gain and NAFLD (OR=1.027, 95%CI=1.002-1.055, P=0.025). We conclude that adult weight gain is strongly associated with NAFLD.

Prevalence and risk factors of fatty liver disease in young and middle-aged population: one center study in Southwestern China

BACKGROUND AND AIM

Fatty liver disease has become common hepatic disease not only in western countries but also in developing countries in Asia-Pacific area. Our aim was to determine the prevalence and risk factors of fatty liver disease as well as its correlation with metabolic syndrome in young and middle-aged population.

METHODS

Data were collected from check-up center at the 1st Affiliated Hospital of Chongqing Medical University in 2011. Relationships of fatty liver disease and age, body mass index, and metabolic syndrome were determined. Logistic regression was performed to identify the risk factors for fatty liver disease.

RESULTS

Data of 18 676 subjects (mean age 40.55 ± 9.94 ranging from 18 to 59) were analyzed. The prevalence of fatty liver disease was 22.0% and increased along with age, body mass index, and the presence and severity of metabolic syndrome. In logistic regression, living area was significantly associated with fatty liver in total population. Male, overweight and obese, waist-to-height ratio ≥ 0.5, hypertension, hypercholesterolemia, high triglyceride, low high-density lipoprotein cholesterol, and fasting plasma glucose ≥ 7.0 mmol/L were common independent risk factors for fatty liver disease in urban and rural areas. Older age and white blood cell over 5.5 ×10(9) /L were related to fatty liver disease in urban area. Obesity was the most important factors in both areas.

CONCLUSION

Fatty liver disease was prevalent in young and middle-aged population and mainly associated to multiple metabolic disorders.

Epidemiology and risk factors of nonalcoholic fatty liver disease (NAFLD)

The nonalcoholic fatty liver disease (NAFLD) is defined as the presence of hepatic steatosis, determined by either imaging or histology, in the absence of secondary causes of hepatic fat accumulation. Nonalcoholic fatty liver is defined as the presence of hepatic steatosis with no evidence of hepatocellular injury in the form of ballooning of the hepatocytes or fibrosis. NASH is defined as the presence of hepatic steatosis and inflammation with hepatocyte injury (ballooning) with or without fibrosis. Although initial epidemiological studies have focused on its prevalence in the Western countries, it is becoming increasingly clear that NAFLD is highly prevalent in the Asia Pacific region, and there may be important distinctions in its phenotype between Asia Pacific and Western countries. Of particular interest are "lean NAFLD" and the "urban-rural divide," which will be discussed in this review article. Obesity, dyslipidemia, type 2 diabetes and metabolic syndrome are established risk factors for developing NAFLD. Many other risk factors (e.g., hypothyroidism, polycystic ovary syndrome, obstructive sleep apnea, hypopituitarism and hypogonadism) for NAFLD have been described in the Western countries, but these associations are yet to be investigated adequately in the Asia Pacific region.

Epidemiology of alcoholic and nonalcoholic fatty liver disease in China

The prevalence of patients presenting with fatty liver disease (FLD) in China has approximately doubled over the past two decades. At present, FLD, which is typically diagnosed by imaging, is highly prevalent (≈ 27% urban population) in China and is mainly related to obesity and metabolic syndrome (MetS). However, the percentage of alcoholic liver disease (ALD) among patients with chronic liver diseases in clinic is increasing as well, and a synergetic effect exists between heavy alcohol drinking and obesity in ALD. Prevalence figures reveal regional variations, with a median prevalence of ALD and nonalcoholic FLD (NAFLD) of 4.5% and 15.0%, respectively. The prevalence of NAFLD in children is 2.1%, although the prevalence increases to 68.2% among obese children. With the increasing pandemic of obesity and MetS in the general population, China is likely to harbor an increasing reservoir of patients with FLD. The risk factors for FLD resemble to those of Caucasian counterparts, but the ethnic-specific definitions of obesity and MetS are more useful in assessment of Chinese people. Therefore, FLD/NAFLD has become a most common chronic liver disease in China. Public health interventions are needed to halt the worldwide trend of obesity and alcohol abuse to ameliorate liver injury and to improve metabolic health.

The future liver of the Asia pacific: fatter and firmer from more fructose and fortune?

The Asia Pacific region is the most diverse and the most populous region in the world. Recent socioeconomic changes have resulted in an emerging epidemic of non-communicable diseases such as type 2 diabetes and nonalcoholic fatty liver disease. The prevalence of nonalcoholic fatty liver disease in Asian Pacific countries now approximates that seen in Western countries. This increase is fueled by rising obesity, partly due to adoption of Western style diets and exposure to compounds such as high fructose corn syrup that are not included in traditional diets. Furthermore, South Asian populations may be more genetically susceptible via the inheritance of polymorphisms in apolipoprotein 3 that increase insulin resistance and nonalcoholic fatty liver disease. Importantly, there remains a substantial lack of data on the incidence and natural history of nonalcoholic steatohepatitis and subsequent complications such as hepatocellular carcinoma in Asian Pacific populations. This information gap prevents estimation of current and future disease burden and impedes efforts to lobby health policymakers to improve public health measures, as given the size of Asian Pacific populations, prevention rather than treatment of non-communicable diseases remains key. This review article addresses these issues and highlights research priorities for nonalcoholic fatty liver disease within the Asia Pacific region.

Obesity as the common soil of non-alcoholic fatty liver disease and diabetes: Role of adipokines

Non‐alcoholic fatty liver disease (NAFLD) describes a spectrum of liver conditions from simple steatosis, steatohepatitis to end‐stage liver disease. The prevalence of NAFLD has been on the rise in many parts of the world, including Asia, and NAFLD is now the liver disease associated with the highest mortality, consequent to the increased risk of cardiovascular diseases and hepatocellular carcinoma. Whereas NAFLD is an independent risk factor for type 2 diabetes, increased hepatic and peripheral insulin resistance contribute to the pathogenesis of both NAFLD and diabetes, which are associated with enhanced cardiovascular risk. Studies in humans and animal models have suggested obesity as the common link of these two diseases, likely mediated by adipose tissue inflammation and dysregulated adipokine production in obesity. In the present review, we discuss recent advances in our understanding of the role of several novel adipokines (adiponectin, adipocyte fatty acid binding protein and fibroblast growth factor‐21) in the pathophysiology of NAFLD and diabetes, as well as their use as potential biomarkers and therapeutic targets for dysglycemia in NAFLD patients.

Epidemiology of a fast emerging disease in the Asia-Pacific region: non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is rapidly increasing in the Asia-Pacific and affects up to 30 % of the general population. In younger children, prevalence has been reported to be between 2.1 and 4.5 %. The prevalence of NAFLD increases with increasing age. NAFLD is more prevalent in men than women, but this trend fades in older age group. NAFLD is one of the most common causes of raised serum ALT levels and the latter is closely related to the presence of features of metabolic syndrome. NAFLD may contribute to metabolic syndrome in a similar way as visceral adiposity and can be an early predictor of metabolic disorders. NAFLD increases the risk of developing diabetes mellitus and is closely related to degree of glucose intolerance. A significant proportion of patients with NAFLD have impaired glucose tolerance or diabetes mellitus but with normal fasting blood glucose, highlighting the importance of oral glucose tolerance test in NAFLD patients with normal fasting blood glucose. Besides liver-related complications, NAFLD has been associated with cardiovascular complications, hyperuricemia, gout, chronic kidney disease, gallstone disease, colorectal adenomatous polyp, and polycystic ovarian syndrome. NAFLD seems to be related to host metabolic factors rather than viral factors and does not seem to affect severity of the liver disease in patients with chronic hepatitis B. On the other hand, hepatic steatosis may be related to both host metabolic and viral factors in patients with chronic hepatitis C and seems to adversely impact on the severity of liver disease and possibly response to antiviral therapy.

Non-alcoholic Fatty Liver Disease: East Versus West

Non-alcoholic fatty liver disease (NAFLD) is an important cause of liver disease worldwide with prevalence ranging from 10% to 30% in various countries. It has become an important cause of unexplained rise in transaminases, cryptogenic cirrhosis, and cryptogenic hepatocellular carcinoma. Pathogenesis is related to obesity, insulin resistance, oxidative stress, lipotoxicity, and resultant inflammation in the liver progressing to fibrosis. Pharmacological treatment in patients with NAFLD is still evolving and the treatment of these patients rests upon lifestyle modification with diet and exercise being the cornerstones of therapy. While there are many similarities between patients with NAFLD from Asia and the West, there are certain features which make the patients with NAFLD from Asia stand apart. This review highlights the data on NAFLD from Asia comparing it with the data from the West.

Non-alcoholic fatty liver disease in a rural, physically active, low income population in Sri Lanka

Background

Non-alcoholic fatty liver disease (NAFLD) is recognized as a metabolic disorder largely seen in urbanized populations. The purpose of this study was to assess prevalence and risk factors for NAFLD in a rural, physically active, economically deprived population in Sri Lanka.

Methods

By visiting individual households in the community, 35-64 year old adults resident in two selected estates in the Nuwara Eliya District of Sri Lanka, were invited to participate in the study. Blood pressure and anthropometric measurements were made on all participants. Blood samples were obtained for the assay of fasting glucose, serum lipids, serum insulin and alanine aminotransferase. NAFLD was diagnosed on established ultrasound criteria for fatty liver in the absence of hepatitis B and C markers and high alcohol consumption.

Results

Of those invited, 403 (65%) participated in the study. Almost all participants were either Indian or Sri Lankan Tamils and 53% were females. Prevalence of NAFLD was 18% in this population. Twice as many males were diagnosed as having NAFLD compared to females. Male sex, high BMI, high waist circumference, high diastolic blood pressure and high plasma glucose levels were significant predictors of NAFLD.

Conclusion

Nearly one in five people in this predominantly Indian Tamil, rural, physically active, economically deprived population had NAFLD. The condition was associated with constituent features of the metabolic syndrome. These results support studies reporting ethnic variations in disease susceptibility and suggest that genetic factors may also play a role in determining disease risk.

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.

Clinical correlation of nonalcoholic fatty liver disease in a Chinese taxi drivers population in Taiwan: Experience at a teaching hospital

BACKGROUND

To explore any gender-related differences in the prevalence of conditions-associated with non-alcoholic fatty liver disease (NAFLD) among Taiwanese taxi drivers in Taipei, Taiwan.

METHODS

We studied 1635 healthy taxi drivers (1541 males and 94 females) who volunteered for physical check-ups in 2006. Blood samples and ultrasound fatty liver sonography results were collected.

RESULTS

The prevalence of NAFLD was 66.4% and revealed no statistically significant decrease with increasing age (p = 0.58). Males exhibited a greater prevalence of NAFLD than did females (67.5% vs 47.9%, p < 0.0001). Gender-related differences for associated factors were found. For males, hypertension, hyperuricemia, higher AST, higher ALT, hypertriglyceridemia, and higher fasting plasma glucose were significantly related to NAFLD. These conditions were not sigfinicantly related to NAFLD in females.

CONCLUSION

Several gender-related differences were noted for NAFLD among Taiwanese taxi drivers.

Is there any progress in the treatment of non-alcoholic fatty liver disease?

Despite the fact that non-alcoholic fatty liver disease (NAFLD) and its severe clinical form, non-alcoholic steatohepatitis, are becoming increasingly prevalent in the industrialised countries, there are no licensed pharmacological treatments for them. Weight loss and life modifications, antioxidant therapies and insulin-sensitising agents are the current treatment strategies and have all been tested with inconclusive results. Low sample numbers, inadequate treatment duration and invalid surrogate markers for treatment response might all account for these results. As NAFLD is a systemic rather than a liver disease, future trials should address the patient as a whole and also address cardiovascular risk factors.

Epidemiology and natural history of non-alcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver condition in many parts of the world. This article describes the epidemiology and natural history of this disorder. It also describes current diagnostic and treatment methods and describes future implications NAFLD may have.

Epidemiology of non-alcoholic fatty liver disease in China

Fatty liver (steatosis) is highly prevalent in China and is more often linked to obesity than to alcoholism. Among more affluent regions of China, the community prevalence of non-alcoholic fatty liver disease (NAFLD) is approximately 15%. With the increasing pandemic of obesity, the prevalence of NAFLD has approximately doubled in the past decade. The risk factors resemble those in other ethnic populations, but it is important to note that ethnic-specific definitions of central obesity, obesity and metabolic syndrome are more useful in assessment of Chinese people. The full range of histological manifestations of NAFLD has been demonstrated in Chinese patients, but to date hepatic severity is generally mild. In contrast to chronic hepatitis C, steatosis is less common in patients with chronic hepatitis B; it is associated with metabolic, and not viral factors and does not appear to affect disease severity. Although long-term outcomes of NAFLD in Chinese populations remain unclear, it may be a predictor of metabolic disorders, diabetes and cardiovascular disease. Public health interventions are therefore indicated to halt or reverse the national trend of obesity in China so as to improve liver as well as metabolic health.

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.

Alcohol consumption and metabolic syndrome among Shanghai adults: a randomized multistage stratified cluster sampling investigation

AIM

To examine the relations of alcohol consumption to the prevalence of metabolic syndrome in Shanghai adults.

METHODS

We performed a cross-sectional analysis of data from the randomized multistage stratified cluster sampling of Shanghai adults, who were evaluated for alcohol consumption and each component of metabolic syndrome, using the adapted U.S. National Cholesterol Education Program criteria. Current alcohol consumption was defined as more than once of alcohol drinking per month.

RESULTS

The study population consisted of 3953 participants (1524 men) with a mean age of 54.3 +/- 12.1 years. Among them, 448 subjects (11.3%) were current alcohol drinkers, including 405 males and 43 females. After adjustment for age and sex, the prevalence of current alcohol drinking and metabolic syndrome in the general population of Shanghai was 13.0% and 15.3%, respectively. Compared with nondrinkers, the prevalence of hypertriglyceridemia and hypertension was higher while the prevalence of abdominal obesity, low serum high-density-lipoprotein cholesterol (HDL-C) and diabetes mellitus was lower in subjects who consumed alcohol twice or more per month, with a trend toward reducing the prevalence of metabolic syndrome. Among the current alcohol drinkers, systolic blood pressure, HDL-C, fasting plasma glucose, and prevalence of hypertriglyceridemia tended to increase with increased alcohol consumption. However, low-density-lipoprotein cholesterol concentration, prevalence of abdominal obesity, low serum HDL-C and metabolic syndrome showed the tendency to decrease. Moreover, these statistically significant differences were independent of gender and age.

CONCLUSION

Current alcohol consumption is associated with a lower prevalence of metabolic syndrome irrespective of alcohol intake (g/d), and has a favorable influence on HDL-C, waist circumference, and possible diabetes mellitus. However, alcohol intake increases the likelihood of hypertension, hypertriglyceridemia and hyperglycemia. The clinical significance of these findings needs further investigation.

How common is non-alcoholic fatty liver disease in the Asia-Pacific region and are there local differences?

Risk factors for development of non-alcoholic steatohepatitis include obesity, especially central adiposity, glucose intolerance or type 2 diabetes mellitus (T2DM), and dyslipidemia. Non-alcoholic fatty liver disease (NAFLD) is now considered a manifestation of metabolic syndrome. During the last two decades, NAFLD has become the most common chronic liver disease in North America and Europe, but until recently was thought to be uncommon (perhaps due to the lack of study) in Asia. Fatty liver can be identified on imaging modalities (ultrasonography, computed tomography scans, and magnetic resonance imaging) with high sensitivity, but steatohepatitis and fibrosis cannot be distinguished. Thus, an inherent drawback in studying the epidemiology of NAFLD is the lack of definitive laboratory tests, no uniform definition-with different studies using cut-off values of alcohol consumption from <20 g/week to 210 g/week, and case selections where biopsy was used for definition. In studies outside the region, the prevalence of NAFLD varies from 16% to 42% by imaging, and 15-39% of liver biopsies. The major risk factors for NAFLD, central obesity, T2DM, dyslipidemia, and metabolic syndrome, are now widely prevalent and are increasing geometrically in the Asia-Pacific region. It is therefore not surprising that NAFLD is common in this region. Estimates of current prevalence range from 5% to 30%, depending on the population studied. Central obesity, diabetes, and metabolic syndrome are the major risk factors. To date, however, data on the natural history and impact of NAFLD causing serious significant chronic liver disease are lacking and there is a need for prospective, cooperative studies.