Hepatic steatosis index: a simple screening tool reflecting nonalcoholic fatty liver disease

BACKGROUND/AIMS

To optimize management of nonalcoholic fatty liver disease (NAFLD), a simple screening tool is necessary. In this study, we aimed to devise a simple index of NAFLD.

STUDY

A cross-sectional study with 10,724 health check-up subjects (5362 cases with NAFLD versus age- and sex-matched controls) was conducted. Study subjects were randomly assigned to a derivation cohort or a validation cohort.

RESULTS

Multivariate analysis indicated that high serum alanine aminotransferase (ALT) to serum aspartate aminotransferase (AST) ratio, high body mass index (BMI), and diabetes mellitus were independent risk factors of NAFLD (all P<0.001). Using these variables, a formula was derived by a logistic regression model: hepatic steatosis index (HSI)= 8 x(ALT/AST ratio)+BMI (+2, if female; +2, if diabetes mellitus). HSI had an area under receiver-operating curve of 0.812 (95% confidence interval, 0.801-0.824). At values of <30.0 or >36.0, HSI ruled out NAFLD with a sensitivity of 93.1%, or detected NAFLD with a specificity of 92.4%, respectively. Of 2692 subjects with HSI <30.0 or >36.0 in the derivation cohort, 2305 (85.6%) were correctly classified. HSI was validated in the subsequent validation cohort.

CONCLUSION

HSI is a simple, efficient screening tool for NAFLD that may be utilized for selecting individuals for liver ultrasonography and for determining the need for lifestyle modifications.

Association between noninvasive fibrosis markers and mortality among adults with nonalcoholic fatty liver disease in the United States

The clinical and public health significance of nonalcoholic fatty liver disease (NAFLD) is not well established. We investigated the long-term effect of NAFLD on mortality. This analysis utilized the National Health and Nutrition Examination Survey conducted in 1988-1994 and subsequent follow-up data for mortality through December 31, 2006. NAFLD was defined by ultrasonographic detection of hepatic steatosis in the absence of other known liver diseases. The presence and severity of hepatic fibrosis in subjects with NAFLD was determined by the NAFLD fibrosis score (NFS), the aspartate aminotransferase to platelet ratio index (APRI), and FIB-4 score. Of 11,154 participants, 34.0% had NAFLD--the majority (71.7%) had NFS consistent with lack of significant fibrosis (NFS <-1.455), whereas 3.2% had a score indicative of advanced fibrosis (NFS >0.676). After a median follow-up of 14.5 years, NAFLD was not associated with higher mortality (age- and sex-adjusted hazard ratio [HR]: 1.05; 95% confidence interval [CI]: 0.93-1.19). In contrast, there was a progressive increase in mortality with advancing fibrosis scores. Compared to subjects without fibrosis, those with a high probability of advanced fibrosis had a 69% increase in mortality (for NFS: HR, 1.69, 95% CI: 1.09-2.63; for APRI: HR, 1.85, 95% CI: 1.02-3.37; for FIB-4: HR, 1.66, 95% CI: 0.98-2.82) after adjustment for other known predictors of mortality. These increases in mortality were almost entirely from cardiovascular causes (for NFS: HR, 3.46, 95% CI: 1.91-6.25; for APRI: HR, 2.53, 95% CI: 1.33-4.83; for FIB-4: HR, 2.68, 95% CI: 1.44-4.99).

CONCLUSIONS

Ultrasonography-diagnosed NAFLD is not associated with increased mortality. However, advanced fibrosis, as determined by noninvasive fibrosis marker panels, is a significant predictor of mortality, mainly from cardiovascular causes, independent of other known factors.

Clinical epidemiology and disease burden of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is defined as the presence of hepatic fat accumulation after the exclusion of other causes of hepatic steatosis, including other causes of liver disease, excessive alcohol consumption, and other conditions that may lead to hepatic steatosis. NAFLD encompasses a broad clinical spectrum ranging from nonalcoholic fatty liver to nonalcoholic steatohepatitis (NASH), advanced fibrosis, cirrhosis, and finally hepatocellular carcinoma (HCC). NAFLD is the most common liver disease in the world and NASH may soon become the most common indication for liver transplantation. Ongoing persistence of obesity with increasing rate of diabetes will increase the prevalence of NAFLD, and as this population ages, many will develop cirrhosis and end-stage liver disease. There has been a general increase in the prevalence of NAFLD, with Asia leading the rise, yet the United States is following closely behind with a rising prevalence from 15% in 2005 to 25% within 5 years. NAFLD is commonly associated with metabolic comorbidities, including obesity, type II diabetes, dyslipidemia, and metabolic syndrome. Our understanding of the pathophysiology of NAFLD is constantly evolving. Based on NAFLD subtypes, it has the potential to progress into advanced fibrosis, end-stage liver disease and HCC. The increasing prevalence of NAFLD with advanced fibrosis, is concerning because patients appear to experience higher liver-related and non-liver-related mortality than the general population. The increased morbidity and mortality, healthcare costs and declining health related quality of life associated with NAFLD makes it a formidable disease, and one that requires more in-depth analysis.

Sarcopenia is an independent risk factor for non-alcoholic steatohepatitis and significant fibrosis

BACKGROUND & AIMS

We explored whether sarcopenia is associated with the histological severity of non-alcoholic fatty liver disease (NAFLD), especially non-alcoholic steatohepatitis (NASH) and significant fibrosis.

METHODS

In a biopsy-proven NAFLD cohort, the appendicular skeletal muscle mass (ASM) was measured. Sarcopenia was defined as a ASM/body weight (ASM%) value beyond two standard deviations below the mean for healthy young adults.

RESULTS

Among the entire set of 309 subjects, the prevalence of sarcopenia in subjects without NAFLD, with non-alcoholic fatty liver (NAFL), and with NASH were 8.7%, 17.9%, and 35.0%, respectively (p<0.001). ASM% was inversely correlated with the severity of fibrosis (p<0.001), and the prevalence of significant fibrosis (⩾F2) was higher in subjects with sarcopenia than in those without (45.7% vs. 24.7%; p<0.001). A crude analysis revealed that sarcopenia was associated with NAFLD (odds ratio [OR], 3.82; 95% confidence interval [CI], 1.58-9.25), which became insignificant after adjustment for body mass index (BMI), diabetes, and hypertension. Among NAFLD subjects, subjects with sarcopenia were more likely to have NASH than those without sarcopenia through a multivariate analysis adjusted for age, gender, BMI, hypertension, diabetes, and smoking status (OR, 2.28; 95% CI, 1.21-4.30), and this finding was obtained even after adjustment for insulin resistance (OR, 2.30; 95% CI, 1.08-4.93). Sarcopenia was also associated with significant fibrosis independent of BMI and insulin resistance (OR, 2.05; 95% CI, 1.01-4.16).

CONCLUSIONS

In this large biopsy-proven NAFLD cohort, sarcopenia was significantly associated with NASH and significant fibrosis.

LAY SUMMARY

Low muscle mass was found to be associated with histological severity in non-alcoholic fatty liver disease, and sarcopenia was significantly associated with non-alcoholic steatohepatitis and significant fibrosis, independent of obesity, inflammation, and insulin resistance. Clinical trial number: NCT 02206841.

Metabolic dysfunction-associated fatty liver disease is associated with increased all-cause mortality in the United States

BACKGROUND & AIMS

Recently, international experts proposed redefining non-alcoholic fatty liver disease (NAFLD) as metabolic dysfunction-associated fatty liver disease (MAFLD), based on modified criteria. It is suspected that outcomes such as mortality may differ for these clinical entities. We studied the impact of MAFLD and NAFLD on all-cause and cause-specific mortality in US adults.

METHODS

We analyzed data from 7,761 participants in the Third National Health and Nutrition Examination Survey and their linked mortality through 2015. NAFLD was diagnosed by ultrasonographic evidence of hepatic steatosis without other known liver diseases. MAFLD was defined based on the criteria proposed by an international expert panel. The Cox proportional hazard model was used to study all-cause mortality and cause-specific mortality between MAFLD and NAFLD, with adjustments for known risk factors.

RESULTS

During a median follow-up of 23 years, individuals with MAFLD had a 17% higher risk of all-cause mortality (hazard ratio [HR] 1.17; 95% CI 1.04-1.32). Furthermore, MAFLD was associated with a higher risk of cardiovascular mortality. NAFLD per se did not increase the risk of all-cause mortality. Individuals who met both definitions had a higher risk of all-cause mortality (HR 1.13, 95% CI 1.00-1.26), while individuals who met the definition for MAFLD but not NAFLD had a 1.7-fold higher risk of all-cause mortality (HR 1.66, 95% CI 1.19-2.32). Estimates for all-cause mortality were higher for those with advanced fibrosis and MAFLD than for those with advanced fibrosis and NAFLD.

CONCLUSIONS

In this US population-based study, MAFLD was associated with an increased risk of all-cause mortality, while NAFLD demonstrated no association with all-cause mortality after adjusting for metabolic risk factors.

LAY SUMMARY

Our findings provide further support for the idea that non-alcoholic fatty liver disease (NAFLD) is a part of a broader multi-system disease that also includes obesity, diabetes, high blood pressure, and high cholesterol. Therefore, re-defining NAFLD as metabolic dysfunction-associated fatty liver disease (MAFLD) may help improve our understanding of predictors that increase the risk of death.

Nonalcoholic fatty liver disease is associated with coronary artery calcification

Nonalcoholic fatty liver disease (NAFLD) is related to risk factors of coronary artery disease, such as dyslipidemia, diabetes, and metabolic syndrome, which are closely linked with visceral adiposity. The aim of this study was to investigate whether NAFLD was associated with coronary artery calcification (CAC), which is used as a surrogate marker for coronary atherosclerosis independent of computed tomography (CT)-measured visceral adiposity. Out of 5,648 subjects who visited one of our health screening centers between 2003 and 2008, we enrolled 4,023 subjects (mean age, 56.9 ± 9.4 years; 60.7% males) without known liver disease or a history of ischemic heart disease. CAC score was evaluated using the Agatston method. On univariate analysis, the presence of CAC (score >0) was significantly associated with age, sex, body mass index, aspartate aminotransferase, alanine aminotransferase, high-density lipoprotein cholesterol, triglycerides, and increased risk of diabetes, hypertension, smoking, and NAFLD. Increasing CAC scores (0, <10, 10-100, ≥ 100) were associated with higher prevalence of NAFLD (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.61-2.10; P<0.001). Multivariable ordinal regression analysis was adjusted for traditional risk factors, and CT-measured visceral adipose tissue area in a subgroup of subjects showed that the increased CAC scores were significantly associated with the presence of NAFLD (OR, 1.28, 95% CI, 1.04-1.59; P = 0.023) independent of visceral adiposity.

CONCLUSION

Patients with NAFLD are at increased risk for coronary atherosclerosis independent of classical coronary risk factors, including visceral adiposity. These data suggest that NAFLD might be an independent risk factor for coronary artery disease.

Nonobese Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) refers to a group of conditions characterized by hepatic steatosis in the absence of significant alcohol consumption. NAFLD is seen commonly in patients with metabolic abnormalities associated with obesity, such as type II diabetes, dyslipidemia, and metabolic syndrome. Evidently, however, not all obese subjects develop NAFLD and, more importantly, NAFLD can be found in nonobese individuals. Although NAFLD occurring in nonobese subjects has been reported in children and adults of all ethnicities, it appears to be recognized more frequently in Asians, even when strict ethnicity-specific body mass index criteria are used to define obesity. Studies based on liver biopsies suggest that the prevalence of nonalcoholic steatohepatitis and fibrosis does not differ significantly between nonobese NAFLD and NAFLD in obese patients. Visceral obesity as opposed to general obesity, high fructose and cholesterol intake, and genetic risk factors (eg, palatin-like phospholipase domain-containing 3) may be associated with nonobese NAFLD. In general, nonalcoholic steatohepatitis is associated with increased mortality, primarily from cardiovascular causes, independent of other metabolic factors. Although data regarding the mortality impact of nonobese NAFLD are not as mature, it may be important to identify high-risk nonobese NAFLD patients and manage their metabolic profile. Currently, lifestyle modification to reduce visceral adiposity, including dietary changes and physical activity, remains the standard of care in patients with nonobese NAFLD.

Non-alcoholic fatty liver disease across the spectrum of hypothyroidism

BACKGROUND & AIMS

The aim of this study was to characterize the relationship between the broad spectrum of hypothyroidism and NAFLD.

METHODS

A cross-sectional study with 4648 health check-up subjects (2324 cases with hypothyroidism vs. age- and sex-matched controls) was conducted. The subjects were categorized as having either subclinical [thyroid-stimulating hormone (TSH) ≥4.1 mIU/L and normal free thyroixine (T(4)) level (0.7-1.8 ng/dl)] or overt hypothyroidism [free T(4)<0.7 ng/dl]. NAFLD was diagnosed on the basis of typical ultrasonographic findings, and alcohol consumption of less than 20 g/day in the absence of other causes of liver disease.

RESULTS

The mean age of the subjects was 48.6±11.8 years and 62.4% were female. NAFLD was significantly associated with hypothyroidism (30.2% patients vs. 19.5% control, p<0.001). The prevalence of NAFLD and abnormal liver enzyme levels (ALT>33/25 IU/L) increased steadily with increasing grades of hypothyroidism (for NAFLD, subclinical: 29.9% and overt: 36.3%; for abnormal ALT, 20.1% and 25.9%, p<0.001, respectively). Multivariate regression analysis showed that NAFLD was statistically significantly associated with hypothyroidism (odds ratio (OR) 1.38, 95% confidence interval (CI), 1.17-1.62) and the grade of hypothyroidism in a dose-dependent manner (OR 1.36, 95% CI, 1.16-1.61 in subclinical hypothyroidism and OR 1.71, 95% CI, 1.10-2.66 in overt hypothyroidism).

CONCLUSIONS

Subclinical hypothyroidism, even in the range of upper normal TSH levels, was found to be related to NAFLD in a dose-dependent manner. Hypothyroidism is closely associated with NAFLD independently of known metabolic risk factors, confirming a relevant clinical relationship between these two diseases.

Advanced fibrosis in nonalcoholic fatty liver disease: noninvasive assessment with MR elastography

PURPOSE

To evaluate the diagnostic accuracy of magnetic resonance (MR) elastography as a method to help diagnose clinically substantial fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) and, by using MR elastography as a reference standard, to compare various laboratory marker panels in the identification of patients with NAFLD and advanced fibrosis.

MATERIALS AND METHODS

This retrospective study was institutional review board approved and HIPAA complaint. Informed consent was waived. This study was conducted in patients with NAFLD, who were identified by imaging characteristics consistent with steatosis in a prospective database that tracks all MR elastographic examinations. Six laboratory-based models of fibrosis were compared with MR elastographic results as well as fibrosis stage from liver biopsy results. The area under the receiver operating characteristic curve (AUROC), sensitivity, specificity, positive predictive value, and negative predictive value of each data set were compared.

RESULTS

Among 325 patients with NAFLD with MR elastographic data, there were 142 patients who underwent liver biopsy within 1 year of MR elastography. When comparing MR elastography results with liver biopsy results, the best cutoff for advanced fibrosis (stage F3-F4, 46 [32.4%] of 142) was 4.15 kPa (AUROC = 0.954, sensitivity = 0.85, specificity = 0.929). This cutoff value identified 104 patients with advanced fibrosis (32.0% of 325 patients). The FIB-4 score (AUROC = 0.827) and NAFLD fibrosis score (AUROC = 0.821) had the best diagnostic accuracy for advanced fibrosis, with high negative predictive values (NAFLD fibrosis score = 0.90 and FIB-4 score = 0.899).

CONCLUSION

MR elastography is a useful diagnostic tool for detecting advanced fibrosis in NAFLD. Of the laboratory-based methods, the NAFLD fibrosis and FIB-4 scores can most reliably detect advanced fibrosis.

Predictors of Outcomes of COVID-19 in Patients With Chronic Liver Disease: US Multi-center Study

BACKGROUND & AIMS

Chronic liver disease (CLD) represents a major global health burden. We undertook this study to identify the factors associated with adverse outcomes in patients with CLD who acquire the novel coronavirus-2019 (COVID-19).

METHODS

We conducted a multi-center, observational cohort study across 21 institutions in the United States (US) of adult patients with CLD and laboratory-confirmed diagnosis of COVID-19 between March 1, 2020 and May 30, 2020. We performed survival analysis to identify independent predictors of all-cause mortality and COVID-19 related mortality, and multivariate logistic regression to determine the risk of severe COVID-19 in patients with CLD.

RESULTS

Of the 978 patients in our cohort, 867 patients (mean age 56.9 ± 14.5 years, 55% male) met inclusion criteria. The overall all-cause mortality was 14.0% (n = 121), and 61.7% (n = 535) had severe COVID-19. Patients presenting with diarrhea or nausea/vomiting were more likely to have severe COVID-19. The liver-specific factors associated with independent risk of higher overall mortality were alcohol-related liver disease (ALD) (hazard ratio [HR] 2.42, 95% confidence interval [CI] 1.29-4.55), decompensated cirrhosis (HR 2.91 [1.70-5.00]) and hepatocellular carcinoma (HCC) (HR 3.31 [1.53-7.16]). Other factors were increasing age, diabetes, hypertension, chronic obstructive pulmonary disease and current smoker. Hispanic ethnicity (odds ratio [OR] 2.33 [1.47-3.70]) and decompensated cirrhosis (OR 2.50 [1.20-5.21]) were independently associated with risk for severe COVID-19.

CONCLUSIONS

The risk factors which predict higher overall mortality among patients with CLD and COVID-19 are ALD, decompensated cirrhosis and HCC. Hispanic ethnicity and decompensated cirrhosis are associated with severe COVID-19. Our results will enable risk stratification and personalization of the management of patients with CLD and COVID-19. Clinicaltrials.gov number NCT04439084.

Metabolic syndrome and visceral obesity as risk factors for reflux oesophagitis: a cross-sectional case-control study of 7078 Koreans undergoing health check-ups

BACKGROUND

Obesity has been associated with reflux oesophagitis. However, the relationship between metabolic syndrome characterised by visceral obesity and reflux oesophagitis is unclear.

AIM

To investigate whether metabolic syndrome or visceral obesity is a risk factor for reflux oesophagitis.

METHODS

A cross-sectional study of 7078 subjects undergoing upper endoscopy during health check-ups was conducted (3539 patients with reflux oesophagitis vs age- and sex-matched controls). We further analysed according to categories of visceral adipose tissue and subcutaneous adipose tissue area with 750 cases and age-, sex- and waist circumference-matched controls who underwent abdominal CT scan.

RESULTS

The prevalence of metabolic syndrome was higher in cases than controls (26.9% vs 18.5%, p<0.001). Multivariate analysis demonstrated that metabolic syndrome is associated with reflux oesophagitis (odds ratio (OR) = 1.42; 95% confidence interval (CI), 1.26 to 1.60). Among the individual components of metabolic syndrome, waist circumference (OR = 1.47; 95% CI, 1.30 to 1.65) and triglyceride (OR = 1.20; 95% CI, 1.05 to 1.36) independently increased the risk for reflux oesophagitis. On sub-analysis, cases showed higher mean visceral adipose tissue area (cm(2)) (136.1 (SD 57.8) vs 124.0 (SD 54.7), p<0.001) and subcutaneous adipose tissue area (cm(2)) (145.9 (SD 56.8) vs 133.5 (SD 50.7), p<0.001). However, only visceral adipose tissue area was an independent risk factor for reflux oesophagitis after adjusting for multiple confounders including smoking, alcohol, body mass index (BMI) and subcutaneous adipose tissue area (OR = 1.60; 95% CI, 1.03 to 2.48, lowest quartile vs highest quartile).

CONCLUSIONS

Metabolic syndrome was associated with reflux oesophagitis. Abdominal obesity, especially visceral obesity, was an important risk factor for reflux oesophagitis.

Changing Trends in Etiology-Based Annual Mortality From Chronic Liver Disease, From 2007 Through 2016

BACKGROUND & AIMS

Although treatment of hepatitis C virus (HCV) infection has improved, the prevalence of alcoholic liver disease (ALD) has been increasing, so we need an updated estimate of the burden and etiology-specific mortality of chronic liver diseases. We studied trends in age-standardized mortality of chronic liver diseases in adults at least 20 years old in the United States from 2007 through 2016.

METHODS

We collected data from the US Census and National Center for Health Statistics mortality records and identified individuals with HCV infection, ALD, nonalcoholic fatty liver disease, or hepatitis B virus infection using ICD-10 codes. We obtained temporal mortality rate patterns using joinpoint trend analysis with estimates of annual percentage change (APC).

RESULTS

Age-standardized HCV-related mortality increased from 7.17 per 100,000 persons in 2007 to 8.14 per 100,000 persons in 2013, followed by a marked decrease in the time period at which patients began receiving treatment with direct-acting antiviral agents (from 8.09 per 100,000 persons in 2014 to 7.15 per 100,000 persons in 2016). The APC in HCV mortality increased 2.0%/year from 2007 through 2014 but decreased 6.4%/year from 2014 through 2016. In contrast, age-standardized mortality increased for ALD (APC 2.3% from 2007 through 2013 and APC 5.5% from 2013 through 2016) and nonalcoholic fatty liver disease (APC 6.1% from 2007 through 2013 and APC 11.3% from 2013 through 2016). Mortality related to hepatitis B virus decreased steadily from 2007 through 2016, with an average APC of -2.1% (95% CI -3.0 to -1.2). Etiology-based mortality in minority populations was higher. HCV-related mortality (per 100,000 persons) was highest in non-Hispanic blacks (10.28) and whites (6.92), followed by Hispanics (5.94), and lowest in non-Hispanic Asians (2.33). Non-Hispanic Asians had higher mortality for hepatitis B virus infection (2.82 per 100,000 vs 1.02 for non-Hispanic blacks and 0.47 for non-Hispanic whites).

CONCLUSION

In our population-based analysis of chronic liver disease mortality in the United States, the decrease in HCV-related mortality coincided with the introduction of direct-acting antiviral therapies, whereas mortality from ALD and nonalcoholic fatty liver disease increased during the same period. Minorities in the United States have disproportionately higher mortality related to chronic liver disease.

Current epidemiology in hepatocellular carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third-leading cause of cancer-related mortality in the world.

AREAS COVERED

This review will discuss risk factors, demographic differences, global trends, and the economic burden of HCC. Viral hepatitis, particularly hepatitis B virus (HBV) infection, is the most common underlying liver disease leading to HCC in those with cirrhosis. Other important risk factors include alcoholic liver disease, nonalcoholic fatty liver disease, metabolic syndrome, etc. With the introduction of direct-acting antiviral agents for hepatitis C virus infection, routine vaccination against HBV, and increasing support for robust public screening programs, the incidence rates for HCC due to viral hepatitis is falling in many countries. Meanwhile, the prevalence of obesity and metabolic syndrome are on the rise, as is NAFLD-related HCC incidence. Asia and Africa have the highest incidence rates of HCC. In multiethnic countries, racial and ethnic minorities experience disparities in HCC incidence as well as mortality, representing an essential area for improvement in terms of healthcare inequity.

EXPERT OPINION

Interventions to minimize the global burden of HCC aim to reduce rates of the most common risk factors and implement effective treatment of underlying etiology and comprehensive screening programs for HCC.

Changing Trends in Etiology-Based and Ethnicity-Based Annual Mortality Rates of Cirrhosis and Hepatocellular Carcinoma in the United States

With recent improvements in the treatment of end-stage liver disease (ESLD), a better understanding of the burden of cirrhosis and hepatocellular carcinoma (HCC) is needed in the United States. A population-based study using the US Census and national mortality database was performed. We identified the age-standardized etiology-specific mortality rates for cirrhosis and HCC among US adults ages 20 years or older from 2007 to 2016. We determined temporal mortality rate patterns by joinpoint analysis with estimates of annual percentage change (APC). Age-standardized cirrhosis-related mortality rates increased from 19.77/100,000 persons in 2007 to 23.67 in 2016 with an annual increase of 2.3% (95% confidence interval [CI] 2.0-2.7). The APC in mortality rates for hepatitis C virus (HCV)-cirrhosis shifted from a 2.9% increase per year during 2007 to 2014 to a 6.5% decline per year during 2014 to 2016. Meanwhile, mortality for cirrhosis from alcoholic liver disease (ALD, APC 4.5%) and NAFLD (APC 15.4%) increased over the same period, whereas mortality for hepatitis B virus (HBV)-cirrhosis decreased with an average APC of -1.1%. HCC-related mortality increased from 3.48/100,000 persons in 2007 to 4.41 in 2016 at an annual rate of 2.0% (95% CI 1.3-2.6). Etiology-specific mortality rates of HCC were largely consistent with cirrhosis-related mortality. Minority populations had a higher burden of HCC-related mortality. Conclusion: Cirrhosis-related and HCC-related mortality rates increased between 2007 and 2016 in the United States. However, mortality rates in HCV-cirrhosis demonstrated a significant decline from 2014 to 2016, during the direct-acting antiviral era. Mortality rates for ALD/NAFLD-cirrhosis and HCC have continued to increase, whereas HBV-cirrhosis-related mortality declined during the 10-year period. Importantly, minorities had a disproportionately higher burden of ESLD-related mortality.

Nonalcoholic Fatty Liver Disease and Metabolic Syndrome

Nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome (MS) are highly prevalent, affecting approximately one-third of the US population. The relationship between NAFLD and MS is complex and may be bidirectionally associated. NAFLD is strongly associated with MS, the components of which include abdominal obesity, hyperglycemia, hypertension, and dyslipidemia. NAFLD associated with certain genetic factors such as the PNPLA3 G allele variant is not accompanied by insulin resistance and MS. Lifestyle modification, including diet and physical activity targeting visceral adiposity, remains the standard of care for patients with NAFLD and MS.

Five-year risk for advanced colorectal neoplasia after initial colonoscopy according to the baseline risk stratification: a prospective study in 2452 asymptomatic Koreans

OBJECTIVE

Postpolypectomy surveillance guidelines for colorectal cancer introduced the concept of 'risk stratification'; however, few studies have been conducted for validation of its usefulness. The aim of this study was to assess the 5-year incidence of advanced neoplasia recurrence based on the risk stratification scheme of the guidelines and to identify its risk factors.

METHODS

A prospective study of surveillance colonoscopy after screening colonoscopy was carried out at the Seoul National University Hospital Healthcare System Gangnam Center. 3803 asymptomatic Koreans aged 50-69 were enrolled prospectively and 5-year cumulative adenoma rates were analysed according to three risk groups: normal (no baseline adenoma), low-risk (1-2 adenomas <10 mm) and high-risk (an advanced adenoma or ≥ 3 adenomas) groups. The RR was computed by HR using Cox proportional regression after multivariate adjustments. The primary outcome was the 5-year cumulative rate of recurrent advanced adenoma in each risk category and the secondary outcome was its predictive factors.

RESULTS

Among 3803 subjects enrolled between 2003 and 2005, 2452 were followed-up within 5 years: 1242, 671 and 539 in the normal, low-risk and high-risk groups, respectively. Compared with the normal group, the low-risk group had a sufficiently low 5-year incidence and did not show an increased risk for subsequent advanced adenoma (2.4% vs 2.0%, HR=1.14, 95% CI 0.61 to 2.17). Conversely, a significantly higher 5-year rate (12.2%) and early recurrence (4.6, 7.4 and 9.6% at 1, 2 and 3 years) of advanced adenoma were revealed in the high-risk group. Among various patients and adenoma characteristics, only high-risk adenoma (HR=5.95, 95% CI 3.66 to 9.68) along with a number of ≥ 3 (HR=3.06, 95% CI 1.51 to 6.57) and size ≥ 10 mm (HR=3.02, 95% CI 1.80 to 5.06) were independent predictors.

CONCLUSIONS

The surveillance interval for low-risk patients could be extended beyond 5 years. Colonoscopic surveillance should be targeted to high-risk patients, and 3-year follow-up after initial polypectomy may be appropriate.

Subclinical Hypothyroidism and Low-Normal Thyroid Function Are Associated With Nonalcoholic Steatohepatitis and Fibrosis

BACKGROUND & AIMS

Variations in level of thyroid-stimulating hormone (TSH) within the reference range of thyroid hormone could have negative health effects. We evaluated the effect of plasma TSH levels within the euthyroid range on the severity of histological damage associated with nonalcoholic fatty liver disease (NAFLD).

METHODS

We performed a cross-sectional study of 425 subjects with biopsy-proven NAFLD (mean age, 53 years; 52% male) who participated in the Boramae NAFLD study from January 2013 to January 2017. Each subject underwent an anthropometric assessment and laboratory and clinical evaluations. Of the subjects, 282 were assigned to a strict-normal thyroid function group (plasma level of TSH, 0.4 to 2.5 mIU/L). Patients with low thyroid function were assigned to groups of subclinical hypothyroidism (plasma level of TSH above 4.5 mIU/L with a normal thyroid hormone level; n = 59) or low-normal thyroid function (higher plasma TSH level [2.5 to 4.5 mIU/L] with a normal thyroid hormone level; n = 84). Multivariate logistic regression analysis was used to identify factors independently associated with nonalcoholic steatohepatitis (NASH) and advanced fibrosis.

RESULTS

NASH and advanced fibrosis were found in higher percentages of subjects with low thyroid function vs strict-normal thyroid function (52.4% vs 37.2% for NASH and 21.0% vs 10.6% for advanced fibrosis; P < .01). Among subjects with low thyroid function, a higher proportion of patients with subclinical hypothyroidism had NASH and associated advanced fibrosis vs patients with low-normal thyroid function (57.6% vs 48.8% for NASH and 25.4% vs 17.9% for advanced fibrosis; P < .01). Subjects with low thyroid function had more extensive hepatic steatosis with greater severity of balloon degeneration and fibrosis. In multivariate analyses, low thyroid function was significantly associated with NASH (odds ratio, 1.61; 95% CI, 1.04-2.50; P = .035) and advanced fibrosis (odds ratio, 2.23; 95% CI, 1.18-4.23; P = .014). Risks of NASH and advanced fibrosis increased significantly with plasma concentration of TSH (Ptrend <.05 for each).

CONCLUSIONS

Subclinical hypothyroidism and low-normal thyroid function are independent predictors of NASH and advanced fibrosis, confirming the relationship between these diseases. ClinicalTrials.gov, Number: NCT02206841.

Body Fat Distribution and the Risk of Incident Metabolic Syndrome: A Longitudinal Cohort Study

The effect of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) area on metabolic syndrome (MS) has been debated. We aimed to evaluate the effects of VAT and SAT on the incidence of MS and its components in a large and apparently healthy Asian population. We performed a longitudinal cohort study of 1,964 subjects who received health screenings over a 5-year follow-up period; 317 incidents of MS (16.1%) were observed during a median follow-up of 4.5 years. The VAT area was significantly associated with a higher incidence of MS; the adjusted HR for incident MS per 1 SD of VAT was 1.50 (95% CI 1.29-1.74), and the adjusted HR of the 5th VAT quintile compared with the 1st quintile was 3.73 (95% CI 2.22-6.28). However, the SAT area was not associated with incident MS. Although the VAT area was longitudinally associated with the incidence of each component of MS, the SAT area was inversely associated with the risk of high blood pressure, fasting blood sugar, and triglycerides, with marginal significance. In conclusion, the VAT area is longitudinally associated with an increased risk of incident MS, while SAT may have a protective effect against the incidence of individual MS components.

Visceral adipose tissue area is an independent risk factor for hepatic steatosis

BACKGROUND AND AIM

Recent data indicate that hepatic steatosis is associated with insulin resistance, dyslipidemia and obesity (especially central body fat distribution). There have been few studies on the correlation between biopsy-proven hepatic steatosis and the above factors in a disease-free population. The aim of the present study was to evaluate the relation between hepatic steatosis assessed by biopsy and clinical characteristics including regional fat distribution measured by computed tomography (CT) in living liver donors.

METHODS

Laboratory data, liver/spleen Hounsfield ratio (L/S ratio), regional fat distribution by CT and liver status by biopsy were evaluated retrospectively in a total of 177 living liver donors without a history of alcohol intake.

RESULTS

The unpaired t-test showed that age, triglycerides (TG), high density lipoprotein, total cholesterol, alanine aminotransferase, body mass index, L/S ratio, visceral adipose tissue area (VAT) and subcutaneous adipose tissue area (SAT) were associated with hepatic steatosis. In the multiple logistic regression analysis, VAT (odds ratio 1.031, 95% CI 1.013-1.048, P < 0.01) and TG (odds ratio 1.012, 95% CI 1.004-1.020, P < 0.01) were independent risk factors of hepatic steatosis. Subgroup analysis also showed that VAT was an independent risk factor in men (odds ratio 1.022, 95% CI 1.003-1.041, P < 0.05) and women (odds ratio 1.086, 95% CI 1.010-1.168, P < 0.05).

CONCLUSION

Our results suggest that visceral abdominal adiposity is correlated with hepatic steatosis in healthy living liver donors.

A low level of serum total testosterone is independently associated with nonalcoholic fatty liver disease

BACKGROUND

The association between low serum testosterone levels, visceral adipose tissue (VAT), and metabolic syndrome is now well known. However, the relationship between hepatic steatosis and serum testosterone levels has not been extensively studied. Our aim was to investigate the association of serum total testosterone levels with nonalcoholic fatty liver disease (NAFLD), adjusting for the influence of VAT and insulin resistance.

METHODS

This study is a retrospective observational cross-sectional one of healthy Korean men and was conducted at the Seoul National University Hospital Healthcare System Gangnam Center. We used data obtained from 495 men who were at least 20 years of age and who had undergone blood testing, abdominal computed tomography, and ultrasonography. Multiple logistic regression analysis was used to explore the association of serum total testosterone levels with NAFLD.

RESULTS

Men in the low serum testosterone quintile were at a higher risk for NAFLD than men in the highest serum testosterone quintile. After adjusting for age, smoking, diabetes, exercise, BMI, triglycerides, and high-density-lipoprotein cholesterol, subjects with serum testosterone levels in the lowest quintile had an odds ratio (OR) (95% confidence interval (CI)) of 5.12 (2.43-10.77) for NAFLD (p value, 0.0004). The inverse association between serum testosterone and NAFLD was attenuated by further adjustment for variables including VAT; however, it remained statistically significant (OR (95% CI): 4.52 (2.09-9.80) in the lowest quintile; p value=0.004).

CONCLUSIONS

A low serum total testosterone level was independently associated with NAFLD. This report is the first one suggesting the association remains unchanged even after controlling for VAT and insulin resistance.

Visceral obesity and insulin resistance as risk factors for colorectal adenoma: a cross-sectional, case-control study

OBJECTIVES

Colorectal adenoma is known to be associated with obesity, but the association between colorectal adenoma and visceral adipose tissue (VAT) area measured by abdominal computed tomography (CT) has not been documented clearly. In addition, the relationship between insulin resistance and colorectal adenomas, which underlies the mechanism that links obesity and colorectal adenoma, has not been studied extensively. The aim of this study was to examine VAT area and insulin resistance as risk factors of colorectal adenoma.

METHODS

A cross-sectional, case-control study was conducted in Koreans that presented for health check-ups. Subjects underwent various laboratory tests, abdominal CT, and colonoscopy. VAT, subcutaneous adipose tissue (SAT), and homeostatic metabolic assessment (HOMA) index were evaluated as potential risk factors of colorectal adenoma in 2,244 age- and sex-matched subjects.

RESULTS

According to univariate analysis, the prevalences of smoking, hypertension, metabolic syndrome, and family history of colorectal cancer were higher in the adenoma group than in the normal control group. In addition, body mass index, waist circumference, triglyceride, high-density lipoprotein cholesterol, and VAT and SAT areas were significantly different in the two groups. According to the multivariate analysis adjusted for multiple confounders, VAT area was independently associated with the risk of colorectal adenoma (odds ratio (OR)=3.09, 95% confidence interval (CI): 2.19-4.36, highest quintile vs. lowest quintile). Mean HOMA index was higher in the adenoma group than in the control group (OR=1.99, 95% CI: 1.35-2.92, highest vs. lowest quintile).

CONCLUSIONS

Visceral obesity was found to be an independent risk factor of colorectal adenoma, and insulin resistance was associated with the presence of colorectal adenoma.

Inadequate Physical Activity and Sedentary Behavior Are Independent Predictors of Nonalcoholic Fatty Liver Disease

BACKGROUND AND AIMS

In general, physical activity (PA) and nonalcoholic fatty liver disease (NAFLD) have an inverse association. However, studies assessing the impact of the widely accepted Physical Activity Guidelines for Americans (PA Guidelines) on NAFLD are lacking.

APPROACH AND RESULTS

We performed a serial, cross-sectional analysis among adults by using the 2007-2016 US National Health and Nutrition Examination Survey. NAFLD and advanced fibrosis were defined by using various noninvasive panels. A PA questionnaire assessed the leisure-time PA, occupation-related PA, transportation-related PA, and total sitting time as sedentary behavior. PA was categorized according to the PA Guidelines. Of the 24,588 individuals (mean age, 47.4 years; 47.9% males), leisure-time PA (≥150 minutes per week) demonstrated 40% lower odds of NAFLD, whereas transportation-related PA was associated with a 33% risk reduction in NAFLD. Analysis of total PA and sitting times simultaneously showed a dose-response association between sitting time and NAFLD (P for trend < 0.001). Compliance with the PA Guidelines was lower in individuals with NAFLD versus those without NAFLD. The trends in compliance with the PA Guidelines for any type of PA remained stable in individuals with NAFLD except for a downtrend in transportation-related PA. In contrast, an improvement in compliance with the PA Guidelines for leisure time was noted in the cohort without NAFLD. Although PA demonstrated a 10% stronger association with risk reduction of NAFLD in women, women showed a lower tendency of meeting the PA Guidelines. Trends in total sitting time increased significantly regardless of NAFLD status.

CONCLUSIONS

Sedentary behavior emerged as an independent predictor of NAFLD. Overall compliance with the PA Guidelines was lower in the cohort with NAFLD, with sex- and ethnicity-based differences. Implementation of these observations in clinical practice may improve our understanding as well as clinical outcomes.

The relation between non-alcoholic fatty liver disease and the risk of coronary heart disease in Koreans

OBJECTIVES

Non-alcoholic fatty liver disease (NAFLD) is known to be related to factors that predict the development of coronary heart disease (CHD), such as dyslipidemia, central obesity, and metabolic syndrome (MS). The aim of this study was to determine whether individuals with NAFLD have an elevated risk of CHD, as estimated using the Framingham risk score (FRS).

METHODS

A total of 21,130 individuals who underwent a voluntary general health examination were recruited. NAFLD was diagnosed among these individuals on the basis of typical sonographic findings and a level of alcohol consumption of <20 g/day. Of the 21,130 individuals, 3,780 were excluded because they had known causes of liver disease (1,690 were alcoholics, 975 had hepatitis B virus, 242 had hepatitis C virus, 91 had other hepatitis history, and 593 were taking medication known to produce fatty liver) or a history of heart disease (189).

RESULTS

NAFLD was diagnosed in 5,769 of the 17,350 individuals (33.3%). The 11,581 normal individuals constituted the control group. The 5,769 individuals with NAFLD were split into two groups on the basis of ultrasonographic findings, that is, into a mild NAFLD group (n=3,278) and a moderate-severe NAFLD group (n=2,491). Individuals with NAFLD had an elevated risk of CHD, as estimated using FRS. Multivariable regression analysis, adjusted for confounding factors, showed a strong association between a higher FRS and NAFLD.

CONCLUSIONS

Individuals with ultrasonographically detected NAFLD have an elevated 10-year risk of developing CHD as estimated using FRS. Furthermore, NAFLD was found to be independently related to the risk of developing CHD, regardless of classical risk factors and other components of MS.

Body Fat Distribution and Risk of Incident and Regressed Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Some studies have examined correlations between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) with nonalcoholic fatty liver disease (NAFLD) or between VAT and NAFLD. We investigated the longitudinal association between body fat distribution (VAT vs SAT) and incidence and regression of NAFLD, adjusting for risk factors, in a large population-based cohort.

METHODS

We collected data from adults who underwent abdominal ultrasonography (to identify liver fat), abdominal fat computed tomography scan, and blood tests from March 2007 through December 2008. Each patient underwent an anthropometric assessment and completed a questionnaire about their medical history, physical activity, and diet. Our final analysis involved 2017 subjects from the initial cohort who participated in a voluntary follow-up health screen performed in 2011 and 2013. The median follow-up time was 4.43 years.

RESULTS

We found 288 incident cases of NAFLD; 159 patients had NAFLD regression during the follow-up period. An increasing area of VAT was associated with higher incidence of NAFLD in the multivariable analysis (highest quintile vs lowest quintile of VAT hazard ratio [HR], 2.23; 95% confidence interval [CI], 1.28-3.89; P for trend = .002; HR, 1.36 [per 1 standard deviation]; 95% CI, 1.16-1.59). An increased area of SAT was significantly associated with regression of NAFLD (highest quintile vs lowest quintile of SAT HR, 2.30; 95% CI, 1.28-4.12; P for trend = .002; HR, 1.36 [per 1 standard deviation]; 95% CI, 1.08-1.72).

CONCLUSIONS

In a large cohort study, larger areas of VAT were longitudinally associated with higher risk of incident NAFLD (during a period of approximately 4 years). In contrast, larger areas of SAT were longitudinally associated with regression of NAFLD. These data indicate that certain types of body fat are risk factors for NAFLD, whereas other types could reduce risk for NAFLD.