Prevalence and related factors of non-alcoholic fatty liver disease among the elderly in Taiwan

Screening strategy for non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, affecting approximately 25% of the general population worldwide, and is forecasted to increase global health burden in the 21st century. With the advancement of non-invasive tests for assessing and monitoring of steatosis and fibrosis, NAFLD screening is now feasible, and is increasingly highlighted in international guidelines related to hepatology, endocrinology, and pediatrics. Identifying high-risk populations (e.g., diabetes mellitus, obesity, metabolic syndrome) based on risk factors and metabolic characteristics for non-invasive screening is crucial and may aid in designing screening strategies to be more precise and effective. Many screening modalities are currently available, from serum-based methods to ultrasonography, transient elastography, and magnetic resonance imaging, although the diagnostic performance, cost, and accessibility of different methods may impact the actual implementation. A two-step assessment with serum-based fibrosis-4 index followed by imaging test vibration-controlled transient elastography can be an option to stratify the risk of liverrelated complications in NAFLD. There is a need for fibrosis surveillance, as well as investigating the cost-effectiveness of different screening algorithms and engaging primary care for first-stage triage screening.

The Association Between Different Obesity Phenotypes and Liver Fibrosis Scores in Elderly Individuals with Fatty Liver in Taiwan

PURPOSE

To examine the association between different phenotypes of obesity or metabolic syndromes and liver fibrosis score in a Taiwanese elderly population with fatty liver.

PATIENTS AND METHODS

This cross-sectional study included 1817 participants aged ≥65 years with fatty liver diagnosed by sonography. We used ethnicity-specific criteria for body mass index and metabolic syndrome, and to define obesity phenotypes as metabolically healthy non-obese (MHNO), metabolically unhealthy non-obese (MUNO), metabolically healthy obese (MHO), and metabolically unhealthy obese (MUO). Correlated fibrosis severity was calculated using the nonalcoholic fatty liver disease (NAFLD) fibrosis score (NFS) and Fibrosis-4 (FIB-4). Fibrosis severity was divided into two categories according to NFS (no-to-mild fibrosis and advanced fibrosis, defined as NFS ≤ 0.676 and >0.676, respectively) and FIB-4 score (no-to-mild fibrosis and advanced fibrosis, defined as FIB-4 score ≤2.67 and >2.67, respectively).

RESULTS

Compared with that in the MHNO group, the associated risk (odds ratio [OR], 95% confidence interval [CI]) of advanced fibrosis by NFS was 2.43 (1.50-3.93), 2.35 (1.25-4.41), and 6.11 (3.90-9.59), whereas that of advanced fibrosis by FIB-4 score was 1.34 (0.83-2.18), 2.37 (1.36-4.13), and 1.38 (0.82-2.31) in the MUNO, MHO, and MUO groups, respectively.

CONCLUSION

Both metabolic syndrome and obesity were positively associated with more advanced fibrosis according to NFS. The detrimental effect of obesity appears to be more than metabolic abnormalities per se in the elderly with more advanced fibrosis severity according to the FIB-4 score.

The Asian Pacific Association for the Study of the Liver clinical practice guidelines for the diagnosis and management of metabolic associated fatty liver disease

Metabolic associated fatty liver disease (MAFLD) is the principal worldwide cause of liver disease and affects nearly a quarter of the global population. The objective of this work was to present the clinical practice guidelines of the Asian Pacific Association for the Study of the Liver (APASL) on MAFLD. The guidelines cover various aspects of MAFLD including its epidemiology, diagnosis, screening, assessment, and treatment. The document is intended for practical use and for setting the stage for advancing clinical practice, knowledge, and research of MAFLD in adults, with specific reference to special groups as necessary. The guidelines also seek to improve patient care and awareness of the disease and assist stakeholders in the decision-making process by providing evidence-based data. The guidelines take into consideration the burden of clinical management for the healthcare sector.

Pathologic findings of patients with nonalcoholic fatty liver disease and the impact of concurrent hepatitis B virus infection in Taiwan

BACKGROUND & AIMS

Pathologic data of non-alcoholic fatty liver disease (NAFLD) was limited and the association between NAFLD and chronic hepatitis B remained unclear in Taiwan. This study aimed to determine the pathological manifestations of NAFLD and the impact of concurrent hepatitis B virus (HBV) infection in a medical center.

METHODS

Retrospective review of 104 consecutive random liver biopsies with the histologic diagnosis of NAFLD or cryptogenic cirrhosis from 2009 to 2018 was conducted. Clinical, biochemical and histological data were compared among various stages of NAFLD and between those with or without concurrent HBV infection.

RESULTS

Advanced fibrosis was documented in 39.42% of Taiwanese patients with NAFLD according to METAVIR scoring system and was associated with aging (odds ratio, 1.06; 95% CI, 1.03-1.10), hypertension (odds ratio, 2.97; 95% CI, 1.31-6.74), diabetes mellitus (odds ratio, 4.36; 95% CI, 1.78-10.70) and concurrent HBV infection (odds ratio, 3.55; 95% CI, 1.46-8.58) by multivariate analyses. Concurrent HBV was found in 28.57% of the NAFLD patients. Patients with concurrent HBV had lower platelet counts, longer prothrombin time/INR and higher fibrosis stage than those without CHB.

CONCLUSION

Advanced fibrosis in patients with NAFLD was common in the biopsy series, and was related to aging, hypertension, diabetes mellitus and concurrent HBV infection.

The changing epidemiology of liver diseases in the Asia-Pacific region

This Review presents current epidemiological trends of the most common liver diseases in Asia-Pacific countries. Hepatitis B virus (HBV) remains the primary cause of cirrhosis; despite declining prevalence in most Asian nations, this virus still poses a severe threat in some territories and regions. Mortality resulting from HBV infection is declining as a result of preventive measures and antiviral treatments. The epidemiological transition of hepatitis C virus (HCV) infection has varied in the region in the past few decades, but the medical burden of infection and the prevalence of its related cancers are increasing. The lack of licensed HCV vaccines highlights the need for novel treatment strategies. The prevalence of nonalcoholic fatty liver disease (NAFLD) has risen in the past decade, mostly owing to increasingly urbanized lifestyles and dietary changes. Alternative herbal medicine and dietary supplements are major causes of drug-induced liver injury (DILI) in some countries. Complications arising from these chronic liver diseases, including cirrhosis and liver cancer, are therefore emerging threats in the Asia-Pacific region. Key strategies to control these liver diseases include monitoring of at-risk populations, implementation of national guidelines and increasing public and physician awareness, in concert with improving access to health care.

Association between smoking and non-alcoholic fatty liver disease: A systematic review and meta-analysis

Background/aims

Non-alcoholic fatty liver disease is one of the most common chronic liver diseases. Some risk factors are known to influence the development of non-alcoholic fatty liver disease, but the effect of tobacco smoking on the progression of non-alcoholic fatty liver disease is controversial. The main goal of this systematic review and meta-analysis is to investigate the association between smoking and non-alcoholic fatty liver disease.

Method

Electronic databases (PubMed, Scopus, and ISI Web of Science) were searched to find published articles on non-alcoholic fatty liver disease and smoking until December 2016. All relevant studies were screened by inclusion and exclusion criteria and compatible studies were chosen. The Newcastle-Ottawa Scale was used to assess the methodological quality of eligible articles. Subsequently, information was gathered based on the following: author, publication year, keywords, country, inclusion and exclusion criteria, main results, study design, conclusion, and confounder variables (age, body mass index, gender, ethnicity, and diabetes). Finally, analyses were performed using Comprehensive Meta-Analysis Software.

Results

Data were extracted from 20 observational studies (9 cross-sectional, 6 case-control, 4 cohort studies, and 1 retrospective cohort study). A significant association was observed between smoking and non-alcoholic fatty liver disease with a pooled odds ratio of 1.110 (95% confidence interval, 1.028-1.199), p-value = 0.008. The statistical heterogeneity was medium with an I2 of 40.012%, p-heterogeneity = 0.074. Also there was a significant relation between non-alcoholic fatty liver disease and passive smoking with a pooled odds ratio of 1.380 (95% confidence interval, 1.199-1.588; p-value = 0.001; I2 = 59.41; p-heterogeneity = 0.117).

Conclusion

Our meta-analysis demonstrated that smoking is significantly associated with non-alcoholic fatty liver disease. Further prospective studies exploring the underlying mechanisms of this association should be pursued. Also passive smoking increases the risk of non-alcoholic fatty liver disease about 1.38-fold. The effects of smoking cigarettes on active smokers (current smoker, former smoker, and total smoker) are less than passive smokers. Further studies are needed to compare the of effects of passive and active smoking on non-alcoholic fatty liver disease.

Global burden of NAFLD and NASH: trends, predictions, risk factors and prevention

NAFLD is one of the most important causes of liver disease worldwide and will probably emerge as the leading cause of end-stage liver disease in the coming decades, with the disease affecting both adults and children. The epidemiology and demographic characteristics of NAFLD vary worldwide, usually parallel to the prevalence of obesity, but a substantial proportion of patients are lean. The large number of patients with NAFLD with potential for progressive liver disease creates challenges for screening, as the diagnosis of NASH necessitates invasive liver biopsy. Furthermore, individuals with NAFLD have a high frequency of metabolic comorbidities and could place a growing strain on health-care systems from their need for management. While awaiting the development effective therapies, this disease warrants the attention of primary care physicians, specialists and health policy makers.

Non-alcoholic fatty liver and advanced fibrosis in the elderly: Results from a community-based Polish survey

BACKGROUND & AIMS

Development of non-alcoholic fatty liver (NAFL) is dependent on metabolic factors occurring at an increased frequency with advancing age. Until now, few studies have explored the prevalence of NAFL in aged populations. Our study aimed to determine the prevalence of NAFL and advanced fibrosis in the elderly population participating in a national survey of a community-based elderly cohort.

METHODS

A total of 3003 participants (mean age 79.6 years, 46.8% male) were enrolled in the study, after applying the following exclusion criteria: individuals younger than 65 years old (n=829) and those with positive serological biomarkers of HBV or HCV infection (n=391), chronic alcohol ingestion (n=727) or incomplete data records (n=745). Based on the fatty liver index (FLI), the participants were classified into three categories: FLI<30 (no NAFL), 30≤FLI<60 (borderline) and FLI≥60 (NAFL). According to the non-alcoholic fatty liver disease (NAFLD) fibrosis score (NFS), the participants were divided into three advanced fibrosis risk categories: NFS<-1.455 (low risk), -1.455≤NFS≤0.676 (intermediate risk) and NFS>0.676 (high risk).

RESULTS

The prevalence of NAFL in the general population was 37.2%; the prevalence reached 51.4% in participants 65-70 years of age and decreased with advancing age (P<.0001). The prevalence of advanced fibrosis was 7.79% (14.8% in the NAFL population) and increased with advancing age (P<.005).

CONCLUSIONS

The prevalence of NAFL and metabolically driven advanced fibrosis are relatively common in the elderly population, and these hepatic conditions run in adverse directions with advancing age.

Nonalcoholic fatty liver disease in Asia: emerging perspectives

As in the West, nonalcoholic fatty liver disease (NAFLD) is the commonest chronic liver disease in Asia, with a prevalence higher than 40 % in some countries. The risk factors for NAFLD development are similar to those in Western countries, including increased body mass index, diabetes, insulin resistance, and metabolic syndrome. NAFLD in Asians is associated with different extrahepatic manifestations involving the cardiovascular, gastrointestinal, and renal systems. A considerable proportion of Asians with NAFLD are described as having "lean" NAFLD. Present in approximately 20 % of the Asian population, lean NAFLD is closely linked with insulin resistance, diabetes, and other metabolic complications, but its association with disease progression to nonalcoholic steatohepatitis and cirrhosis remains to be defined. There is emerging evidence of the interactions of NAFLD with hepatitis B virus and hepatitis C virus infection in Asia. Unlike in Western countries, NAFLD constitutes only a minority of cirrhosis and hepatocellular carcinoma cases in Asia. Possible explanations are the lower prevalence of obesity and the overwhelming problem of viral hepatitis in Asia. With aging of the obesity cohort in Asia, NAFLD-related liver complications are expected to increase.