Upper limits of normal for alanine aminotransferase activity in the United States population

ALT Levels for Asians With Metabolic Diseases: A Meta-analysis of 86 Studies With Individual Patient Data Validation

The current alanine aminotransferase (ALT) upper limit of normal was defined using selected healthy Caucasian blood donors. Given the global rise in obesity and different body habitus in Asians, we aimed to perform a systematic review and meta-analysis combined with bootstrap modeling and individual patient data validation to estimate the ALT upper threshold for Asians, including the overweight and diabetics. We included studies from PubMed, Embase, and Cochrane database searches that identified individuals without known liver diseases (i.e., viral hepatitis, alcohol, and ultrasound-detected nonalcoholic fatty liver disease). The mean ALT (U/L) was estimated using a random-effects mixed model and upper threshold (95th-percentile value, U/L) via a bootstrap model with 10,000 resamples. We screened 4,995 studies and identified 86 studies that reported ALT values for 526,641 individuals without excessive alcohol intake or known liver diseases, yielding a mean ALT of 19 and ALT upper threshold of 32. The ALT upper threshold was 37 in males versus 31 in females, 39 in overweight versus 28 in normal-weight individuals, and 36 for diabetics versus 33 for nondiabetics. We validated our study level data with individual patient level data in 6,058 individuals from five study centers in Japan. Consistent with our study-level data, we found that the ALT upper threshold in our individual patient data analysis was indeed higher in overweight versus normal-weight individuals (39 vs. 32) and in diabetics versus nondiabetics (42 vs. 33). Conclusion: We provide validated reference ranges for ALT upper threshold derived from Asians without known liver disease, including individuals with ultrasound-detected nonalcoholic fatty liver disease who are normal weight, overweight, nondiabetic, and diabetic, to inform practice.

Combined Effect of PNPLA3, TM6SF2, and HSD17B13 Variants on Risk of Cirrhosis and Hepatocellular Carcinoma in the General Population

BACKGROUND AND AIMS

We hypothesized that a genetic risk score (GRS) for fatty liver disease influences the risk of cirrhosis and hepatocellular carcinoma (HCC). Three genetic variants (patatin-like phospholipase domain-containing protein 3 [PNPLA3] p.I148M; transmembrane 6, superfamily member 2 [TM6SF2] p.E167K; and hydroxysteroid 17-beta dehydrogenase 13 [HSD17B13] rs72613567) were combined into a risk score, ranging from 0 to 6 for risk-increasing alleles.

APPROACH AND RESULTS

We examined the association of the risk score with plasma markers of liver disease and with cirrhosis and HCC in 110,761 individuals from Copenhagen, Denmark, and 334,691 individuals from the UK Biobank. The frequencies of risk scores of 0, 1, 2, 3, 4, and 5 or 6 were 5%, 25%, 41%, 23%, 5.5%, and 0.5%, respectively. A higher GRS was associated with an increase in plasma alanine aminotransferase (ALT) level of 26% in those with score 5 or 6 versus 0. In meta-analysis of the Copenhagen studies and the UK Biobank, individuals with scores 1, 2, 3, 4, and 5 or 6 had odds ratios (ORs) for cirrhosis of 1.6 (95% confidence interval [CI], 1.3, 1.9), 2.0 (95% CI, 1.8, 2.2), 3.1 (95% CI, 2.7, 3.5), 5.2 (95% CI, 4.2, 6.4), and 12 (95% CI, 7.7, 19), respectively, as compared with those with a score of 0. The corresponding ORs for HCC were 1.2 (95% CI, 0.9, 1.7), 1.0 (95% CI, 0.7, 1.3), 2.4 (95% CI, 1.9, 3.0), 3.3 (95% CI, 2.2, 5.0), and 29 (95% CI, 17, 51).

CONCLUSION

A GRS for fatty liver disease confers up to a 12-fold higher risk of cirrhosis and up to a 29-fold higher risk of HCC in individuals from the general population.

Risk of metabolic syndrome in participants within the normal range of alanine aminotransferase: A population-based nationwide study

This study aimed to investigate the risk of metabolic syndrome (MS) in participants whose alanine aminotransferase (ALT) levels were within the normal range in the general population. A cross-sectional study was conducted using nationally representative samples from the Korea National Health and Nutrition Examination Survey 2007-2015. A total of 43,402 adults (men, 17,535; women, 25,867) with ALT ≤40 U/L without a history of hepatitis B and C, liver cirrhosis, or liver cancer were analyzed. The risk of MS was evaluated according to the ALT level. The prevalence of MS significantly increased as the ALT levels increased. The proportions of MS in men were 12.6%, 25.2%, and 39.7% in the ALT levels of <15, 15~30, and 30~40 U/L, respectively (p < 0.001), and those of women were 7.2%, 23.3%, and 44.7% in the ALT levels of <10, 10~20, and 20~40 U/L, respectively (p < 0.001). There was an ALT-dependent relationship in the risk of MS in participants with normal ALT level after adjustment for age, alcohol intake, and body mass index. The adjusted odds ratio (aOR) of MS in men was 2.48 (95% confidence interval [CI], 2.16-2.85) in an ALT level of 30~40 U/L compared with that in ALT <15 U/L (p < 0.001), and the aOR of MS in women was 2.67 (95% CI, 2.26-3.15) in an ALT level of 20~40 U/L compared with that in ALT <10 U/L (p < 0.001). Although within the normal range of ALT, the risk of MS increases as the ALT levels increase. The ALT level in the general population without a history of chronic liver disease may be a useful marker to evaluate for MS.

Burden of Disease due to Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is rapidly becoming the most common liver disease in both Western populations and other parts of the world. This review discusses the prevalence and incidence of NAFLD in various regions around the world. The methodology used to identify the epidemiology and classify the stages of the disease is described. The impact of the disease on individuals, looking at both liver-related and extrahepatic consequences of the disease, is then discussed. Finally, the economic and societal impact of the disease is discussed.

Unresolved issues of immune tolerance in chronic hepatitis B

During the natural course of chronic hepatitis B virus infection, immune-tolerant phase is characterized by high viral replication, the presence of HBV e antigen (HBeAg), and normal or minimally elevated serum alanine aminotransferase. Immune-tolerant phase is usually regarded as a benign course of the disease. International guidelines recommend observation rather than treatment during immune-tolerant phase. In this article, we review unresolved issues related to the definition of true immune-tolerant phase and the benefit of antiviral treatment. Defining true immune-tolerant phase requires a careful approach and long-term follow-up. In previous studies, many patients were misclassified as being immune-tolerant phase. Noninvasive methods of assessing fibrosis are warranted for patients in the immune-tolerant phase. Yet, there has been controversy over the benefit and harm of antiviral treatment for immune-tolerant phase patients. Thus, further larger scale studies are needed to investigate the prognosis of patients in true immune-tolerant phase and their need for antiviral therapy.

Upper Normal Limit of Serum Alanine Aminotransferase and Its Association with Metabolic Risk Factors in Pars Cohort Study

BACKGROUND

The range of serum alanine aminotransferase (ALT) varies in different sub-populations or countries. Its population-specific cut-off points may provide a more effective screening tool for non-alcoholic fatty liver disease (NAFLD). Objectives To investigate the upper normal level (UNL) of ALT and its association with metabolic syndrome (MS) in a semi-urban population in southern Iran.

METHODS

The baseline data of Pars Cohort Study was used. A total of 9264 subjects aged 40-75 years were enrolled. UNL of ALT was estimated based on 95 percentile of ALT in participants who had body mass index (BMI) < 25. Multivariable logistic regression was applied and adjusted odds ratio (OR) and its 95% confidence interval (CI) were estimated.

RESULTS

95 percentile of ALT was 41.71 U/L and 32.9 U/L in men and women, respectively. Abnormal waist circumference (OR: 1.72, 95%CI: 1.34, 2.21), triglyceride (OR: 1.63, 95%CI: 1.25, 2.13), fasting blood sugar (OR: 1.69, 95%CI: 1.32, 2.16), cholesterol level (OR: 1.06, 95%CI: 1.03, 1.09) and systolic blood pressure (OR: 1.08, 95%CI: 1.01, 1.16) were independently associated with ALT.

CONCLUSION

UNL of ALT in southern Iranian women is lower than the current recommended level, while these are almost the same for men. MS components are highly common in southern Iran and are associated with elevated serum ALT. Further studies are recommended to estimate the UNL of serum ALT among the Iranian population with NAFLD.

Towards Genotype-Specific Care for Chronic Hepatitis B: The First 6 Years Follow Up From the CHARM Cohort Study

Objective

There is increasing evidence to suggest that, among those with chronic hepatitis B virus infection, the natural history and rate of progression to cirrhosis and hepatocellular carcinoma is influenced by hepatitis B virus genotype. The unique hepatitis B virus genotype C4 circulates among Indigenous Australians. The aim of this work is to describe the process of establishing this cohort and review the first 6 years of available data in an effort to understand the real-world clinical care and natural history of this subgenotype.

Method

We followed a longitudinal cohort of Indigenous Australians from the Northern Territory of Australia with established subgenotype C4 infections. We assigned phases of disease according to Gastroenterological Society of Australia and Asian Pacific Association for the Study of the Liver criteria using clinical and laboratory information that had been collected for clinical management.

Results

Of 193 patients followed over a median of 38 months, 58 (30%) individuals transitioned from 1 disease phase to another, 10 (5%) cleared hepatitis B e antigen, and 6 cleared hepatitis B surface antigen (3%). In this relatively young cohort (median age 40.3 years), 26 (13%) had cirrhosis by the end of the follow up period, with the majority of these being in the immune control phase of disease.

Conclusions

In this cohort of hepatitis B subgenotype C4 patients, we report an aggressive and dynamic clinical phenotype. High rates of cirrhosis at a young age appear to occur in the early phases of disease.

Low Alanine Aminotransferase Cut-Off for Predicting Liver Outcomes; A Nationwide Population-Based Longitudinal Cohort Study

BACKGROUND AND AIM

Recent practice guidelines suggest healthy normal alanine aminotransferase (ALT) levels should be less than 30 U/L for males and 19 U/L for females. We tried to validate the prediction power of the "low cut off" for liver related outcomes in the general population.

METHODS

A total of 426,013 subjects were followed up for 10 years using the National Health Screening Cohort database. Prediction ability of long term mortality and liver related outcomes between conventional (<40 U/L in men and women) and low (<30 U/L in men and <19 U/L in women) ALT cut-off values were compared.

RESULTS

Both conventional and low ALT cut-offs predicted liver related unfavorable outcomes in Kaplan-Meier analysis. Following adjustment for age, body mass index, smoking, exercise, alcohol consumption, fasting blood glucose, and cholesterol via multivariate Cox regression, abnormal ALT using new 'low ALT cut off' was a significant independent predictor for liver-related mortality, HCC, and decompensated liver events. When the low cut-off criteria were added to the prediction model, the ability to predetect liver-related hard outcomes significantly increased in both men and women (p-values < 0.0001). The C-index values for predicting liver-related adverse events were the same in both ALT cut-offs, after adjusting confounding factors (C index value: 0.73~0.88).

CONCLUSIONS

New low ALT cut-off showed good prediction power for liver related unfavorable outcomes.

Effect of viral load on pregnancy outcomes in chronic hepatitis B infection

AIM

This study aimed to evaluate perinatal and neonatal outcomes in pregnant women with chronic hepatitis B virus infection based on infection status and to identify cut-off values based on hepatitis B virus DNA viral load to predict composite adverse perinatal/neonatal outcomes.

METHODS

Pregnant women with chronic hepatitis B virus who delivered at Hacettepe University between 2010 and 2018 were evaluated retrospectively. We included 95 patients. The patients were classified into two groups based on laboratory findings and viral load: group 1 (n = 63), immune inactive; and group 2 (n = 32), immune active. Maternal age, gravidity, parity, gestational week at birth, birth weight, 5th minute APGAR scores and composite perinatal and neonatal outcomes were compared between groups.

RESULTS

Gestational week at birth, birth weight and 5th minute APGAR score in group 2 were lower than those in group 1 (P < 0.001, P < 0.005 and P < 0.001, respectively). The rates of composite adverse perinatal/neonatal outcome, preterm birth, fetal growth restriction, oligohydramnios, pre-eclampsia, admission to the neonatal intensive care unit, small for gestational age and 5th minute APGAR score less than 7 were significantly higher in group 2 (P < 0.001). Hepatitis B virus DNA viral load of 17 515 IU/mL (72.7% sensitivity, 78.1% specificity) and 17 515 IU/mL (81.8% sensitivity, 80.8% specificity) were determined to be cut-off values for composite adverse perinatal and neonatal outcomes, respectively.

CONCLUSION

Care should be taken in patients with a viral load of greater than 17 515 IU/mL, and pregnancy should be postponed until the inactive phase of the disease for optimal results.

Clinical significance of elevated liver transaminases in HIV-infected patients

: Elevation of liver transaminases is common in patients infected with the HIV. Although this is usually an incidental finding during regular work-up, HIV-infected patients with transaminase elevations require additional visits for laboratory studies and clinical assessments, and often undergo interruptions and changes in antiretroviral therapy (ART). Alanine aminotransferase is present primarily in the liver, thus being a surrogate marker of hepatocellular injury. Aspartate aminotransferase is present in the liver and other organs, namely cardiac and skeletal muscle, kidney and brain. Serum levels of both liver transaminases predict liver-related mortality. Moreover, serum fibrosis biomarkers based on alanine aminotransferase and aspartate aminotransferase predict all-cause mortality. In a busy clinical setting, a diagnostic approach to elevated liver transaminases could be complicated given the frequency and nonspecificity of this finding. Indeed, HIV-infected individuals present multiple risk factors for liver damage and chronic elevation of transaminases, including coinfection with hepatitis B and C viruses, alcohol abuse, hepatotoxicity due to ART, HIV itself and frequent metabolic comorbidities leading to nonalcoholic fatty liver disease. This review provides an update on epidemiology of elevated liver transaminases, summarizes the main etiologic contributors and discusses the prognostic significance and a pragmatic approach to this frequent finding in the clinical practice of HIV medicine. With the aging of the HIV-infected population following the successful implementation of ART in Western countries, liver-related conditions are now a major comorbidity in this setting. As such, clinicians should be aware of the frequency, clinical significance and diagnostic approach to elevated liver transaminases.

A Review of Non-Alcoholic Fatty Liver Disease in HIV-Infected Patients: The Next Big Thing?

The burden of liver-related morbidity remains high among HIV-infected patients, despite advances in the treatment of HIV and viral hepatitis. Especially, the impact of non-alcoholic fatty liver disease (NAFLD) is significant with a prevalence of up to 50%. The pathogenesis of NAFLD and the reasons for progression to non-alcoholic steatohepatitis (NASH) are still not fully elucidated, but insulin resistance, mitochondrial dysfunction and dyslipidemia seem to be the main drivers. Both HIV-infection itself and combination antiretroviral therapy (cART) can contribute to the development of NAFLD/NASH in various ways. As ongoing HIV-related immune activation is associated with insulin resistance, early initiation of cART is needed to limit its duration. In addition, the use of early-generation nucleoside reverse transcriptase inhibitors and protease inhibitors is also associated with the development of NAFLD/NASH. Patients at risk should therefore receive antiretroviral drugs with a more favorable metabolic profile. Only weight reduction is considered to be an effective therapy for all patients with NAFLD/NASH, although certain drugs are available for specific subgroups. Since patients with NASH are at risk of developing liver cirrhosis and hepatocellular carcinoma, several non-antifibrotic and antifibrotic drugs are under investigation in clinical trials to broaden the therapeutic options. The epidemiology and etiology of NAFLD/NASH in HIV-positive patients is likely to change in the near future. Current guidelines recommend early initiation of cART that is less likely to induce insulin resistance, mitochondrial dysfunction and dyslipidemia. In contrast, as a result of increasing life expectancy in good health, this population will adopt the more traditional risk factors for NAFLD/NASH. HIV-treating physicians should be aware of the etiology, pathogenesis and treatment of NAFLD/NASH in order to identify and treat the patients at risk.

Association between urinary thiodiglycolic acid level and hepatic function or fibrosis index in school-aged children living near a petrochemical complex

The effect of exposure to vinyl chloride monomer (VCM) on susceptibility to hepatotoxicity in children is unknown, although experimental studies have demonstrated a significantly increased risk of hepatocellular carcinoma in rodents exposed to VCM in early life. Epidemiological studies have revealed a high prevalence of liver fibrosis and abnormal liver function in workers exposed to high VCM levels. We aimed to assess the association among urinary thiodiglycolic acid (TDGA) level, abnormal liver function, and hepatic fibrosis in school-aged children living near a petrochemical complex. A total of 303 school-aged (6-13 years) children within 10 km nearly a petrochemical complex was recruited in central Taiwan. First-morning urine and blood samples were collected from each subject, and urinary TDGA level was analyzed through liquid chromatography-tandem mass spectrometry. Liver function was determined by serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. Hepatic fibrosis was assessed using the AST to platelet ratio index (APRI) and fibrosis-4 score (FIB-4). Risk of hepatotoxicity induced by TDGA exposure was estimated using multivariate logistic regression. The median (range, subclinically abnormal %) AST and ALT levels of all subjects were 26.0 (17.0-99.0, 25.7%) and 15.0 (7.0-211.0, 5.9%) IU/L, respectively. Children in the highest urinary TDGA quartile (≥160.0 μg/g creatinine) exhibited significantly elevated median AST levels compared with those in the lowest quartiles (<35.4 μg/g creatinine, p = 0.033). After adjustment for potential confounding factors, children in the highest quartiles (Q₄) of TDGA level had significantly increased odds ratio (OR) of subclinically abnormal AST (OR = 3.86; 95% confidence interval: 1.54-9.67) compared with those in the lowest quartile. A dose-response trend (p = 0.004) was observed. Our findings support the hypothesis that elevated urinary TDGA level in children living near petrochemical complex is associated with susceptibility to hepatotoxicity.

Necessity of lowering the upper limit of normal of alanine aminotransferase in patients with chronic hepatitis B

AIM

To explore the necessity of lowering the upper limit of normal of alanine aminotransferase (ALT) in patients with chronic hepatitis B (CHB).

METHODS

A total of 715 CHB patients with undetectable HBV DNA were studied. Of them, 57 were inactive HBsAg carriers (carrier group), 455 were those who previously met antiviral criterion and achieved viral and biochemical response (hepatitis group), and 203 underwent liver biopsy due to their baseline ALT less than 2 times the upper limit of normal (ULN) and accepted antiviral treatment (including 133 cases with ALT < 1 x ULN and 70 cases with ALT 1-2 x ULN) (biopsy group). Clinical data including age, gender, weight, liver function, blood glucose, blood lipids, routine blood parameters, HBV markers, HBV DNA, alpha fetoprotein, and ultrasound findings were collected. Inflammation grade, fibrosis stage and liver function data were also collected for patients in the biopsy group after one year of antiviral therapy.

RESULTS

ALT median value was 19 IU/L and the 95% percentile was 31.2 IU/L (95%CI: 30-34 IU/L) in all patients (n = 715). The 95% percentile was 34 IU/L in males (95%CI: 31-35 IU/L), and 26.2 IU/L in females (95%CI: 25-30 IU/L). ALT value decreased significantly in the biopsy group after antiviral treatment, and median ALT decreased from 37 IU/L to 23 IU/L, which showed a significant difference (F = 111.497, P = 0.000). Based on four different ALT ULN, the detection rates of significant inflammation (≥G2) were 0, 38.78%, 63.27% and 84.69%, respectively, in the biopsy group. When ROC was used to analyze ALT and significant histological inflammation, the AUC value was 0.751. Logistic regression analysis showed that ALT was not associated with significant histological inflammation (P = 0.331).

CONCLUSION

The current ALT ULN is relatively high for assessment of liver inflammation in patients with CHB, and there may be a necessity to lower the threshold.

A liver health hui: hepatitis C knowledge and associated risk factors in New Zealand gang members and their families

Hepatitis C virus (HCV) and B virus (HBV) infections are highly prevalent, with a high percentage of undiagnosed cases. Knowledge of HCV and its modes of transmission are essential for disease prevention and management. We studied a high-risk New Zealand gang population on viral hepatitis prevalence, their level of knowledge and the liver health risk factors in a community setting. Participants completed demographic, risk factor and knowledge questionnaires in three health meetings in New Zealand. Participants' blood samples were tested for HBV, HCV, biochemical indicators of liver disease. Liver fibrosis levels were assessed using a Fibroscan® device. We studied 52 adult Mongrel Mob members, affiliates and whānau (extended family) throughout New Zealand. We identified no HCV and two HBV cases, confirmed high-risk factor levels and poor associated knowledge, with a significant association between lack of knowledge and presence of specific risk factors. We successfully conducted a community-focused, high-risk, hard-to-reach gang population study, and found a link between lack of knowledge and risk factors for HCV infection. This study provided first-of-its-kind data on viral hepatitis in a gang population and demonstrated the need for educational screening programmes to aid early HCV detection, prevention and treatment.

Nonalcoholic Fatty Liver Disease and Risk of Diabetes: A Prospective Study in China

OBJECTIVE

We aimed to investigate whether liver steatosis severity affects the risk of developing diabetes in a large cohort study.

METHODS

We prospectively examined the association in 41,650 Chinese adults with negative hepatitis-B surface antigen who were free of alcohol consumption, diabetes, and liver cirrhosis at baseline. Cox proportional models were used to estimate the risk of diabetes after a mean of 3.6 years of follow-up. Nonalcoholic fatty liver disease (NAFLD) was assessed with hepatic ultrasonography. Elevated alanine transaminase (ALT) was defined as ALT concentrations >19 and >30 U/L in females and males, respectively. Diabetes was defined as a fasting glucose ³7.0 mmol/L or treatment with hypoglycemic medication.

RESULTS

Liver steatosis severity was significantly associated with higher risks of developing diabetes (adjusted hazard ratio [HR] for severe vs. without NAFLD = 2.66, 95% confidence interval [CI]: 2.17-3.25, P-trend<.001) and impaired fasting glucose (fasting glucose between 5.6 and 6.9 mmol/L, adjusted HR = 1.36, 95% CI: 1.16-1.59, P-trend<.001), as well as a faster increase rate of fasting glucose concentrations ( P-trend<.001), during 3.6 years of follow-up. Elevated ALT was also associated with incident diabetes (HR = 1.12, 95% CI: 1.02-1.22), adjusting for NAFLD and other covariates.

CONCLUSION

We observed a dose-response relationship between liver steatosis severity and increased diabetes risk, and ALT may predict incident diabetes independently of NAFLD.

ABBREVIATIONS

ALT = alanine transaminase; BP = blood pressure; CI = confidence interval; HCV = hepatitis C virus; HR = hazard ratio; IFG = impaired fasting glucose; NAFLD = nonalcoholic fatty liver disease; ULN = upper limit of normal.

Long-Term Outcomes After Drug-Induced Liver Injury

Purpose of the review

This review serves to update the reader on emerging data regarding a spectrum of drug-induced liver injury (DILI) outcomes that lie between complete resolution and acute liver failure. Such outcomes can range from mild chronic injury to late liver failure and mortality.

Recent findings

Several large registries are maturing with large numbers of DILI cases thus shedding light on outcomes including chronic injury and late fatality. We cover definitions commonly used to describe resolution versus chronic injury and mortality due to DILI. We look at rates of occurrence for these different outcomes in major registries. Three specific types of chronic DILI that are illustrative but also easily missed by clinicians are also described.

Summary

A small but important proportion of DILI cases do not resolve, going on to develop chronic injury and even liver failure. Defining and recognizing these cases is a challenge because DILI is rare, and chronic injury rarer still. Large registries are beginning to define these previously overlooked long term outcomes.

Nonalcoholic fatty liver disease with elevated alanine aminotransferase levels is negatively associated with bone mineral density: Cross-sectional study in U.S. adults

Background

Nonalcoholic fatty liver disease (NAFLD) has been reported to have a negative effect on bone mineral density (BMD) in Asian populations. Whether such an association exists in Western populations is less clear.

Methods

This cross-sectional analysis of data from NHANES III, a United States national health survey conducted from 1988 to 1994, included 6089 participants aged 40–75 years, selected after excluding people with hepatitis virus serology, elevated alcohol consumption, decreased renal function, or steroid use, and pregnant females. The main outcome, BMD at the femoral neck, was measured using dual-energy X-ray absorptiometry. The primary exposure, NAFLD, was defined as moderate or severe hepatic steatosis diagnosed using abdominal ultrasonography.

Result

After controlling for gender and menopausal status, race/ethnicity, age and body mass index, NAFLD was not significantly associated with BMD (beta coefficient: −0.006, 95%CI: −0.016, 0.003). A secondary analysis categorized participants with NAFLD according to their serum alanine aminotransferase (ALT) levels into high and normal ALT NAFLD groups, and compared these with the non-NAFLD group. NAFLD with higher levels of ALT was associated with lower levels of BMD (beta coefficient: −0.023, 95% CI: −0.044, −0.002).

Conclusion

This study showed a relationship between NAFLD with high ALT and lower BMD in the general U.S. population.

Where should the safe limits of alcohol consumption stand in light of liver enzyme abnormalities in alcohol consumers?

Objectives

To estimate the prevalence and risk factors for abnormal liver enzymes in a large age- and gender stratified population-based sample of apparently healthy individuals with or without alcohol consumption and other health-related risk factors (adiposity, physical inactivity, smoking).

Methods

Data on alcohol use, smoking, diet and physical activity were recorded using structured questionnaires from 13,976 subjects (6513 men, 7463 women, aged 25–74 years) in the national FINRISK studies. Alcohol data was used to categorize the participants into abstainers, light drinkers, moderate drinkers and heavy drinkers. Serum gamma-glutamyltransferase (GGT) and alanine aminotransferase (ALT) activities were measured using standard kinetic methods.

Results

Male light drinkers, moderate drinkers and heavy drinkers showed significantly higher relative risks of abnormal GGT than abstainers: 1.37 (95% confidence interval 1.11 to 1.71, p < 0.01), 2.72 (2.08 to 3.56, p < 0.0005), and 6.10 (4.55 to 7.17, p < 0.0005), respectively. Corresponding values for women were 1.22 (0.99 to 1.51, p = 0.065), 1.90 (1.44 to 2.51, p < 0.0005), and 5.91 (3.80 to 9.17, p < 0.0005). Estimated threshold doses for a significant GGT elevation was 14 standard weekly alcohol doses for men and 7 for women. Excess body weight and age over 40 years modulated the thresholds towards smaller quantities of alcohol. The risk of abnormal GGT was also significantly influenced by physical inactivity and smoking. The relative risks of abnormal ALT activities were increased in male heavy drinkers, especially in those presenting with adiposity and sedentary lifestyle.

Conclusions

Alcohol use markedly increases the risk for abnormal liver enzyme activities in those presenting with age over 40 years, obesity, smoking or sedentary lifestyle. The data should be considered in public health recommendations and in the definitions of safe limits of alcohol use.

An assessment of racial differences in the upper limits of normal ALT levels in children and the effect of obesity on elevated values

OBJECTIVES

Childhood obesity is a risk factor for non-alcoholic fatty liver disease and poses important public health issues for children. Racial differences in alanine aminotransferase (ALT) levels among children have not been described. This study aimed to identify racial differences in upper limit normal (ULN) ALT levels and evaluate the effect of obesity on elevated levels in children without other metabolic risk factors.

METHODS

National Health and Nutrition Examination Surveys and clinical data from the Loyola University Health System were used to determine ULN ALT by race and gender. Quantile regression was used to evaluate the impact of obesity on elevated ALT and to identify potential risk factors for ALT above the ULN.

RESULTS

Upper limit normal (ULN) ALT was approximately 28.0 and 21.0-24.0 U/L for boys and girls, respectively. No significant difference in ULN ALT across race was observed. Obesity was significantly associated with elevated ALT; obese children with elevated ALT had values 10 U/L higher than normal-weight children.

CONCLUSIONS

Racial differences in ALT levels among adults are not evident in children. Obesity, in the absence of metabolic risk factors and other causes of liver disease, is associated with elevated ALT, providing evidence against the concept of healthy obesity in children.

A decade of HIV care in rural Tanzania: Trends in clinical outcomes and impact of clinic optimisation in an open, prospective cohort

Objectives

Our objectives were to describe trends in enrolment and clinical outcomes in the open, prospective Kilombero and Ulanga Antiretroviral Cohort (KIULARCO) in the Morogoro region of southern Tanzania, and identify strengths and areas for improvement in the care of HIV-positive individuals in rural Tanzania.

Methods

We included adults (≥15 years) and children (<15 years) enrolled in the cohort in 2005–2014. The cohort underwent significant changes from autumn 2012 to optimise care. We evaluated mortality and loss to follow-up (LTFU) using competing risks methods, ART usage, opportunistic infections (OI), co-infections and laboratory abnormalities.

Results

Overall, 7010 adults and 680 children were enrolled; enrolment peaked in 2008 but has increased steadily since 2011. Among adults (65% female; median age 37 [interquartile range 31–45] years), the proportion referred from hospital wards quadrupled in 2013–14 versus earlier years. 653 (9%) adults died and 2648 (38%) were LTFU; the five-year cumulative probabilities of death and LTFU were 10.3% and 44.0%, respectively. Among children, 69 (10%) died and 225 (33%) were LTFU. The corresponding five-year probabilities were 12.1% and 39.6%. Adult ART use (regardless of eligibility) increased from 5% in 2005 to 89% in 2014 (similarly among children), with 9% on second-line therapy in 2014 (17% of children). OI diagnoses increased over time; tuberculosis prevalence at enrolment quadrupled from 6% in 2011 to 26% in 2014. The proportion of newly-enrolled participants assessed for laboratory abnormalities peaked at nearly 100% in 2014 (from a minimum of 24%), yet abnormality prevalences remained fairly constant.

Conclusions

In this cohort, ART usage improved dramatically and is approaching targets of 90%. Improved screening led to increases in detection of OIs and laboratory abnormalities, suggesting that a large number of these co-morbidities previously went undetected and untreated. Further work will address the high LTFU rates and implications for mortality estimates, and the management and outcomes of co-morbidities.

National Survey of Adult and Pediatric Reference Intervals in Clinical Laboratories across Canada: A Report of the CSCC Working Group on Reference Interval Harmonization

OBJECTIVE

Reference intervals are widely used decision-making tools in laboratory medicine, serving as health-associated standards to interpret laboratory test results. Numerous studies have shown wide variation in reference intervals, even between laboratories using assays from the same manufacturer. Lack of consistency in either sample measurement or reference intervals across laboratories challenges the expectation of standardized patient care regardless of testing location. Here, we present data from a national survey conducted by the Canadian Society of Clinical Chemists (CSCC) Reference Interval Harmonization (hRI) Working Group that examines variation in laboratory reference sample measurements, as well as pediatric and adult reference intervals currently used in clinical practice across Canada.

DESIGN AND METHODS

Data on reference intervals currently used by 37 laboratories were collected through a national survey to examine the variation in reference intervals for seven common laboratory tests. Additionally, 40 clinical laboratories participated in a baseline assessment by measuring six analytes in a reference sample.

RESULTS

Of the seven analytes examined, alanine aminotransferase (ALT), alkaline phosphatase (ALP), and creatinine reference intervals were most variable. As expected, reference interval variation was more substantial in the pediatric population and varied between laboratories using the same instrumentation. Reference sample results differed between laboratories, particularly for ALT and free thyroxine (FT4). Reference interval variation was greater than test result variation for the majority of analytes.

CONCLUSION

It is evident that there is a critical lack of harmonization in laboratory reference intervals, particularly for the pediatric population. Furthermore, the observed variation in reference intervals across instruments cannot be explained by the bias between the results obtained on instruments by different manufacturers.

Features of nonalcoholic steatohepatitis in severely obese children and adolescents undergoing sleeve gastrectomy

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is an underrecognized co-morbidity of obesity. The characteristic features and severity of NAFLD in severe childhood obesity remain unknown.

OBJECTIVES

To investigate features of NAFLD in obese children and identify predictors of significant disease.

SETTING

Academic center with a standardized pathway for pediatric bariatric surgery and a dedicated multidisciplinary team.

DESIGN

This is a baseline cross-sectional analysis for a data set obtained from a prospective clinical outcome study that included severely obese children (≤14 yr of age) and adolescents (14-21 yr of age) who underwent laparoscopic sleeve gastrectomy between March 2008 and March 2015. Patients with syndromic obesity, history of alcohol intake, parenteral nutrition, liver disease, intake of medications that may affect NAFLD and weight, and insufficient tissue biopsy were excluded. Prevalence and features of nonalcoholic steatohepatitis (NASH) and clinically significant liver fibrosis in different pediatric age groups and noninvasive predictors in severe childhood obesity were evaluated.

RESULTS

The 296 patients in the study group (1:1 sex distribution) had a mean body mass index and age of 48.4±9.8 kg/m² and 14.5±3.6 years, respectively. According to histopathology assessment, 225 (76%) patients had NAFLD, of whom 118 patients (39.9% of the total cohort) had NASH. Additionally, 110 (37.2%) had clinically significant (stage 2+) fibrosis and 256 (86.5%) had portal inflammation. Those with NASH were younger than those without NASH (P = .02; prevalence of NASH in children aged≤10 yr = 64.9%) and were more likely to be male (P = .003). Of children aged≤10 years, 60% had clinically significant fibrosis compared with 32% of older patients (P = .03). High-density lipoproteins, triglycerides, glycated hemoglobin, alanine transaminase, and systolic and diastolic blood pressure levels were most predictive of fibrosis. For NASH, triglycerides, homeostatic model assessment of insulin resistance, glycated hemoglobin, alkaline phosphatase, aspartate transaminase, and alanine transaminase were most predictive.

CONCLUSIONS

In our setting, 65% of severely obese young children had NASH, and 60% had clinically significant liver fibrosis. Young age, male sex, and features of metabolic syndrome were significantly associated with NASH and liver fibrosis in severely obese pediatric patients.

Safety of Biologic and Nonbiologic Disease-modifying Antirheumatic Drug Therapy in Veterans with Rheumatoid Arthritis and Hepatitis C Virus Infection

Objective.

To examine the effect of disease-modifying antirheumatic drug (DMARD) therapy on hepatotoxicity among patients with rheumatoid arthritis (RA) and hepatitis C virus (HCV) infection.

Methods.

We identified biologic and nonbiologic treatment episodes of patients with RA using the 1997–2011 national data from the US Veterans Health Administration. Eligible episodes had HCV infection (defined by detectable HCV RNA) and subsequently initiated a new biologic or nonbiologic DMARD. Cohort entry required a baseline alanine aminotransferase (ALT) < 66 IU/l and quantifiable HCV RNA within 90 days prior to starting biologic/DMARD therapy. The primary outcome of interest was hepatotoxicity, defined as ALT elevation ≥ 100 IU/l or increase in HCV RNA of 1 log or more, and was examined within the first year of biologic/DMARD use. Results were reported as the cumulative incidence of treatment episodes achieving predefined hepatotoxicity at 3, 6, and 12 months after biologic/DMARD initiation.

Results.

RA patients with HCV (n = 748) were identified and contributed 1097 biologic/DMARD treatment episodes. Overall, ALT elevations were uncommon, with 37 (3.4%) hepatotoxicity events occurring within 12 months. Treatment episodes with biologic DMARD demonstrated more frequency of hepatotoxicity than did nonbiologic DMARD (4.8% vs 2.3%, p = 0.03). Among treatment episodes involving hepatotoxicity events, the majority occurred within 6 months of DMARD initiation (29/37, 78%).

Conclusion.

In US veterans with HCV and RA receiving biologic and nonbiologic DMARD, the frequency of hepatotoxicity (ALT ≥ 100 IU/l) was low, with a higher frequency observed in treatment episodes with current biologic use.

Prevalence of elevated alanine transaminase in Australia and its relationship to metabolic risk factors: A cross-sectional study of 9,447 people

BACKGROUND AND AIM

Elevated alanine transaminase (ALT) is a strong predictor of metabolic syndrome, but there are few data from the Australian population. We aimed to determine the prevalence of elevated ALT and association with metabolic risk factors.

METHODS

In this cross-sectional study including adult participants (N = 9,447) from a nationwide, population-based survey, we assessed the prevalence of elevated ALT [defined as ≥ 40 IU/L (men) and ≥ 30 IU/L (women) as baseline, and ALT as ≥ 30 IU/L (men) and ≥ 19 IU/L (women) as lower threshold], distribution of metabolic risk factors, and independent predictors of elevated ALT in logistic regression models. Analyses were weighted to the population with population weights.

RESULTS

Elevated ALT levels were found in 11.2% of the Australian population. People with elevated ALT were younger (43 vs 46 yrs) with more truncal adiposity (100 vs 91 cm), higher pro-atherogenic lipids and glucose and exercised less (120 vs 160 min per week, P < 0.05 for all analyses). Regression analyses indicated that younger age, male sex, diabetes, triglycerides, apolipoprotein B, and waist circumference were independent predictors of elevated ALT. The population attributable fraction of elevated ALT due to truncal obesity was estimated at 47%.

CONCLUSION

These data demonstrate a high prevalence of elevated ALT in the general population that is closely associated with metabolic risk factors. Individuals with elevated ALT should be evaluated for co-existent metabolic disorders.

Shorter Leukocyte Telomere Length in Relation to Presumed Nonalcoholic Fatty Liver Disease in Mexican-American Men in NHANES 1999-2002

Leukocyte telomere length is shorter in response to chronic disease processes associated with inflammation such as diabetes mellitus and coronary artery disease. Data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2002 was used to explore the relationship between leukocyte telomere length and presumed NAFLD, as indicated by elevated serum alanine aminotransferase (ALT) levels, obesity, or abdominal obesity. Logistic regression models were used to evaluate the relationship between telomere length and presumed markers of NAFLD adjusting for possible confounders. There was no relationship between elevated ALT levels, abdominal obesity, or obesity and telomere length in adjusted models in NHANES (OR 1.13, 95% CI 0.48-2.65; OR 1.17, 95% CI 0.52-2.62, resp.). Mexican-American men had shorter telomere length in relation to presumed NAFLD (OR 0.07, 95% CI 0.006-0.79) and using different indicators of NAFLD (OR 0.012, 95% CI 0.0006-0.24). Mexican origin with presumed NAFLD had shorter telomere length than men in other population groups. Longitudinal studies are necessary to evaluate the role of telomere length as a potential predictor to assess pathogenesis of NALFD in Mexicans.

ACG Clinical Guideline: Evaluation of Abnormal Liver Chemistries

Clinicians are required to assess abnormal liver chemistries on a daily basis. The most common liver chemistries ordered are serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase and bilirubin. These tests should be termed liver chemistries or liver tests. Hepatocellular injury is defined as disproportionate elevation of AST and ALT levels compared with alkaline phosphatase levels. Cholestatic injury is defined as disproportionate elevation of alkaline phosphatase level as compared with AST and ALT levels. The majority of bilirubin circulates as unconjugated bilirubin and an elevated conjugated bilirubin implies hepatocellular disease or cholestasis. Multiple studies have demonstrated that the presence of an elevated ALT has been associated with increased liver-related mortality. A true healthy normal ALT level ranges from 29 to 33 IU/l for males, 19 to 25 IU/l for females and levels above this should be assessed. The degree of elevation of ALT and or AST in the clinical setting helps guide the evaluation. The evaluation of hepatocellular injury includes testing for viral hepatitis A, B, and C, assessment for nonalcoholic fatty liver disease and alcoholic liver disease, screening for hereditary hemochromatosis, autoimmune hepatitis, Wilson's disease, and alpha-1 antitrypsin deficiency. In addition, a history of prescribed and over-the-counter medicines should be sought. For the evaluation of an alkaline phosphatase elevation determined to be of hepatic origin, testing for primary biliary cholangitis and primary sclerosing cholangitis should be undertaken. Total bilirubin elevation can occur in either cholestatic or hepatocellular diseases. Elevated total serum bilirubin levels should be fractionated to direct and indirect bilirubin fractions and an elevated serum conjugated bilirubin implies hepatocellular disease or biliary obstruction in most settings. A liver biopsy may be considered when serologic testing and imaging fails to elucidate a diagnosis, to stage a condition, or when multiple diagnoses are possible.

Increased risk of nonalcoholic fatty liver disease with occupational stress in Chinese policemen: A 4-year cohort study

Nonalcoholic fatty liver disease (NAFLD) and occupational stress have been recognized as major public health concerns. We aimed to explore whether occupational stress was associated with NAFLD in a police population.A total of 6559 male police officers were recruited for this prospective study in April 2007. Among them, 2367 eligible subjects participated in follow-up from 2008 to 2011. NAFLD was diagnosed based on standard criteria. Occupational stress was evaluated by Occupational Stress Inventory-Revised scores.The incidence of NAFLD was 31.2% in the entire police. After adjusting for traditional risk factors, moderate occupational stress (MOS), high occupational stress (HOS), and high personal strain (HPS) were risk factors (MOS: hazard ratio [HR] = 1.237, 95% confidence interval [CI] = 1.049-1.460; HOS: HR = 1.727, 95% CI = 1.405-2.124; HPS: HR = 3.602, 95% CI = 1.912-6.787); and low occupational stress (LOS) and low personal strain (LPS) were protective factors (LOS: HR = 0.366, 95% CI = 0.173-0.776; LPS: HR = 0.490, 95% CI = 0.262-0.919) for NAFLD in the entire police cohort. HOS and HPS remained robust among traffic police.HOS and HPS were independent predictors for the development of NAFLD in a Chinese police population. Additional future prospective investigations are warranted to validate our findings.

Trends in the Burden of Nonalcoholic Fatty Liver Disease in a United States Cohort of Veterans

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in the United States. However, few data are available on recent trends in the incidence and prevalence of NAFLD in the U.S.

METHODS

We analyzed the national Veterans Administration databases from 2003 to 2011 and calculated the age-adjusted prevalence and incidence of NAFLD for the overall sample of patients and by demographic subgroups. We used a previously validated algorithm to define NAFLD, which was based on persistent increases in levels of liver enzymes in the absence of positive results from tests for hepatitis C or hepatitis B or evidence of excessive alcohol use.

RESULTS

Of the 9,784,541 patients with at least 1 visit to the Veterans Administration between 2003 and 2011, 1,330,600 patients (13.6%) had NAFLD. The annual incidence rates of NAFLD remained stable (from 2.2% to 3.2%) during the study duration. The prevalence of NAFLD increased from 6.3% in 2003 (95% confidence interval, 6.26%-6.3%) to 17.6% in 2011 (95% confidence interval, 17.58%-17.65%), a 2.8-fold increase. The incidence and prevalence increased at significantly greater rates in patients younger than 45 years vs older patients.

CONCLUSIONS

In a U.S. population, the annual incidence of NAFLD ranges from 2% to 3%. The prevalence of NAFLD more than doubled from 2003 through 2011; it is likely to continue to increase because of a steady overall incidence coupled with a rising incidence in younger individuals.

Trends in the Burden of Nonalcoholic Fatty Liver Disease in a United States Cohort of Veterans

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in the United States. However, few data are available on recent trends in the incidence and prevalence of NAFLD in the U.S.

METHODS

We analyzed the national Veterans Administration databases from 2003 to 2011 and calculated the age-adjusted prevalence and incidence of NAFLD for the overall sample of patients and by demographic subgroups. We used a previously validated algorithm to define NAFLD, which was based on persistent increases in levels of liver enzymes in the absence of positive results from tests for hepatitis C or hepatitis B or evidence of excessive alcohol use.

RESULTS

Of the 9,784,541 patients with at least 1 visit to the Veterans Administration between 2003 and 2011, 1,330,600 patients (13.6%) had NAFLD. The annual incidence rates of NAFLD remained stable (from 2.2% to 3.2%) during the study duration. The prevalence of NAFLD increased from 6.3% in 2003 (95% confidence interval, 6.26%-6.3%) to 17.6% in 2011 (95% confidence interval, 17.58%-17.65%), a 2.8-fold increase. The incidence and prevalence increased at significantly greater rates in patients younger than 45 years vs older patients.

CONCLUSIONS

In a U.S. population, the annual incidence of NAFLD ranges from 2% to 3%. The prevalence of NAFLD more than doubled from 2003 through 2011; it is likely to continue to increase because of a steady overall incidence coupled with a rising incidence in younger individuals.

Biomarker-Based Approaches for Assessing Alcohol Use Disorders

Although alcohol use disorders rank among the leading public health problems worldwide, hazardous drinking practices and associated morbidity continue to remain underdiagnosed. It is postulated here that a more systematic use of biomarkers improves the detection of the specific role of alcohol abuse behind poor health. Interventions should be initiated by obtaining information on the actual amounts of recent alcohol consumption through questionnaires and measurements of ethanol and its specific metabolites, such as ethyl glucuronide. Carbohydrate-deficient transferrin is a valuable tool for assessing chronic heavy drinking. Activities of common liver enzymes can be used for screening ethanol-induced liver dysfunction and to provide information on the risk of co-morbidities including insulin resistance, metabolic syndrome and vascular diseases. Conventional biomarkers supplemented with indices of immune activation and fibrogenesis can help to assess the severity and prognosis of ethanol-induced tissue damage. Many ethanol-sensitive biomarkers respond to the status of oxidative stress, and their levels are modulated by factors of life style, including weight gain, physical exercise or coffee consumption in an age- and gender-dependent manner. Therefore, further attention should be paid to defining safe limits of ethanol intake in various demographic categories and establishing common reference intervals for biomarkers of alcohol use disorders.

Factors affecting awareness of non-alcoholic fatty liver disease among the general public and health care providers

Because of the indolent asymptomatic nature of non-alcoholic fatty liver disease (NAFLD), it is often neglected. However, more and more evidence has suggested that NAFLD is not a benign disease and it can progress to liver cirrhosis and hepatocellular carcinoma. Patients with NAFLD have higher mortality, mainly due to liver and cardiovascular diseases, compared with the overall population. Earlier recognition of NAFLD can slow its progression, prevent complications and reduce cardiovascular-related outcomes. However, current estimates of NAFLD awareness indicate that the level of awareness of NAFLD among both the general public and health care providers remains unacceptably low. Understanding the awareness of NAFLD and identifying the related factors could help guide the implementation of awareness efforts and result in more optimized disease prevention and management.

Obesity and the extent of liver damage among adult New Zealanders: findings from a national survey

Objective

Non‐alcoholic fatty liver disease (NAFLD), defined as excessive fat accumulation in hepatocytes when no other pathologic causes are present, is an increasingly common obesity‐related disorder. We sought to describe the prevalence of elevated liver enzymes, a marker of liver damage, among New Zealand adults, and high‐risk subgroups including those with an elevated body mass index and those with pre‐diabetes or diabetes, to gain a better understanding of the burden of liver disease.

Methods

A total of 4,721 New Zealanders aged 15+ years participated in a nationally representative nutrition survey. Liver enzymes, alanine transaminase (ALT) and gamma glutamyl transpeptidase (GGT) were measured in serum. Results were available for 3,035 participants, of whom 10.8% were Māori and 4.5% Pacific.

Results

Overall, the prevalence of elevated ALT and elevated GGT was 13.1% (95% confidence interval [CI]: 11.2 – 15.0) and 13.7% (95% CI: 12.0 – 15.4), respectively. Odds ratios for an elevated ALT or GGT markedly increased with increasing body mass index. Men with obesity had the highest elevated ALT prevalence (28.5%; 95% CI: 21.7–35.4), and women with diabetes had the highest elevated GGT prevalence (36.5%; 95% CI: 26.0–47.0). Adding alcohol consumption categories to each of the adjusted models did not meaningfully change any results, although for women, heavy alcohol consumption was associated with an elevated GGT (overall p = 0.03).

Conclusions

Obesity‐related liver disease is likely to increasingly burden the New Zealand health sector and contribute to health disparities unless effective obesity treatment and prevention measures are given high priority. © 2015 The Authors. Obesity Science & Practice published by John Wiley & Sons Ltd, World Obesity and The Obesity Society.

Alanine aminotransferase and mortality in patients with type 2 diabetes (ZODIAC-38)

INTRODUCTION

Combined data suggest a bimodal association of alanine aminotransferase (ALT) with mortality in the general population. Little is known about the association of ALT with mortality in patients with type 2 diabetes. We therefore investigated the association of ALT with all-cause, cardiovascular and noncardiovascular mortality in patients with type 2 diabetes.

DESIGN

A prospective study was performed in patients with type 2 diabetes, treated in primary care, participating in the Zwolle Outpatient Diabetes project Integrating Available Care (ZODIAC) study. Cox regression analyses were performed to determine the associations of log2 -transformed baseline ALT with all-cause, cardiovascular and noncardiovascular mortality.

RESULTS

In 1187 patients with type 2 diabetes (67 ± 12 years, 45% female), ALT levels were 11 (8-16) U/L. During median follow-up for 11.1 (6.1-14.0) years, 553 (47%) patients died, with 238 (20%) attributable to cardiovascular causes. Overall, ALT was inversely associated with all-cause mortality (hazard ratio [HR] 0.81; 95% confidence interval [CI] 0.72-0.92), independently of potential confounders. This was less attributable to cardiovascular mortality (HR 0.87; 95% CI 0.72-1.05), than to noncardiovascular mortality (HR 0.77; 95% CI 0.65-0.90). Despite the overall inverse association of ALT with mortality, it appeared that a bimodal association with all-cause mortality was present with increasing risk for levels of ALT above normal (P = 0.003).

DISCUSSION

In patients with type 2 diabetes, low levels of ALT are associated with an increased risk of all-cause mortality, in particular noncardiovascular mortality, compared to normal levels of ALT, while risk again starts to increase when levels are above normal.

Elevated liver enzymes following polytraumatic injury

This retrospective cohort study examined the prevalence and potential risk factors for elevated liver enzymes in patients following traumatic brain injury (TBI). The participants were servicemembers with TBI admitted to the Polytrauma Rehabilitation Center (PRC) at the Hunter Holmes McGuire Department of Veterans Affairs Medical Center in Richmond, Virginia, from January 2008 through December 2011. The PRC had 207 patients during this time period, 121 of whom had a liver panel within 30 d of injury. Patients were retrospectively analyzed and placed into one of two categories based on alanine aminotransferase (ALT) values. Of the 121 subjects, 59 (49%) had an ALT of 44 IU/L or greater on their initial set of laboratories. These subjects were compared with those with an ALT of 43 IU/L or less using chi square analysis. There were no significant differences between the two groups with regards to sex, military status, race, theater, TBI mechanism, severity of TBI, or concomitant injuries. Regardless of demographics, mechanism of injury, or extent of trauma, elevated liver enzymes are common in patients admitted to the rehabilitation unit following TBI. For the majority of these patients, enzymes returned to normal with conservative management. In most cases, no specific etiology was ever defined. Further analysis will be performed to determine the most efficient way to monitor these patients so that unnecessary test are avoided and medical expenses are minimized.

Shenfu decoction as adjuvant therapy for improving quality of life and hepatic dysfunction in patients with symptomatic chronic heart failure

ETHNOPHARMACOLOGICAL RELEVANCE

Shenfu decoction (SFD) is a water extract of the dried root or root stalk of Panax ginseng C. A. Mey (Asian ginseng) and the lateral root of Aconitum carmichaeli Debx (prepared by Fuzi, Heishunpian in Chinese). It has been used to treat heart failure for over a thousand years. The main active components of SFD, ginsenosides and higenamine, enhance heart contractility, increase the coronary blood supply, improve ischemic myocardial metabolism, scavenge free radicals and protect myocardial ultrastructure.

AIM OF THE STUDY

To investigate the effect of SFD on quality of life (QOL) and hepatic function in symptomatic chronic heart failure (CHF) patients.

MATERIALS AND METHODS

Forty patients enrolled in the study were randomized into two groups: an SFD group (18 cases) and a control group (22 cases). All the patients received standard heart failure therapy, and the SFD group patients were also treated with Shenfu granules for 14 days as an adjunctive therapy. The effects of SFD on QOL, plasma alanine aminotransferase (ALT) level, cardiac function, left ventricular ejection fraction (LVEF) and tumor necrosis factor-α (TNF-α) level were studied. ALT threshold in hepatic injury are 21U/L for men and 17U/L for women.

RESULTS

Minnesota Living with Heart Failure Questionnaire (MLHFQ) scores were improved by 35.27±10.72 vs. 23.87±11.96 in the SFD and control groups respectively (p<0.01). Subgroup analysis of the MLHFQ results demonstrated that both physical and emotional scores were significantly higher in the SFD group (21.00±5.66 vs. 16.75±6.25, p<0.05; 4.64±4.84 vs. 1.13±2.85, p<0.05). Circulating ALT was significantly decreased by SFD (13.3IU/L vs. 0.6IU/L, p<0.01). The grading of cardiac function and LVEF were increased by 1.6±0.5 vs. 1.1±0.3 and 18%±13% vs. 8%±8% in the SFD and control groups respectively (p<0.05 and p<0.05). The level of TNF-α declined more in SFD than control group (64.8±5.0 to 57.6±4.1, p<0.05; vs. 61.6±5.9 vs. 57.7±3.2. p>0.05).

CONCLUSION

Compared with standard heart failure treatment, oral SFD as an adjuvant therapy significantly improved QOL and hepatic injury in CHF patients.

Increased liver markers are associated with higher risk of type 2 diabetes

AIM: To investigate the association between liver markers and the risk of type 2 diabetes (T2DM) and impaired fasting glucose (IFG).

METHODS: A total of 8863 participants (3408 men and 5455 women) over 30 years of age were analyzed from the fifth Korean National Health and Nutrition Examination Survey (2010-2011). The associations of serum liver markers such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), AST/ALT, and gamma-glutamyltransferase (GGT) with T2DM and IFG were analyzed using logistic regression models. Participants were divided into sex-specific quartiles on the basis of liver markers.

RESULTS: The prevalence of T2DM and IFG were 11.3% and 18.3%. Increasing quartiles of ALT and GGT were positively and AST/ALT were negatively correlated with T2DM and IFG. Analysis of the liver marker combinations showed that if any two or more markers were in the highest risk quartile, the risks of both T2DM and IFG increased significantly. The risk was greatest when the highest ALT and GGT and lowest AST/ALT quartile were combined, with the risk of T2DM at 3.21 (95%CI: 1.829-5.622, P < 0.001) in men and 4.60 (95%CI: 3.217-6.582, P < 0.001) in women. Men and women with the highest AST and ALT and lowest AST/ALT quartile had a 1.99 and 2.40 times increased risk of IFG.

CONCLUSION: Higher levels of GGT and ALT and lower AST/ALT within the physiological range are independent, additive risk factors of T2DM and IFG.

Liver enzyme levels and hepatic iron content in Fatty liver: a noninvasive assessment in general population by T2* mapping

RATIONALE AND OBJECTIVES

Existing evidence suggests potential contribution of iron in pathogenesis of nonalcoholic fatty liver disease (NAFLD). We aimed to investigate whether hepatic iron content correlates with liver enzyme levels in NAFLD using a noninvasive magnetic resonance imaging (MRI) technique.

MATERIALS AND METHODS

Subjects from Golestan Cohort Study were randomly selected. Diagnosis of NAFLD was made by combination of ultrasound and MRI. Subjects with NAFLD were divided into two groups with high (H-NAFLD) and low (L-NAFLD) enzyme level according to 95th percentile of alanine aminotransferase (ALT) value in normal population. Quantitative T2* maps of entire cross-sectional area of liver were calculated on pixel-by-pixel basis using a semiautomated software.

RESULTS

A total of 207 subjects were enrolled. Mean T2* values were significantly lower in NAFLD group than controls (P < .001) indicating higher iron content. Male subjects with H-NAFLD had statistically lower T2* values than those with L-NAFLD in multivariate analysis (odds ratio, 0.74; 95% confidence interval [CI], 0.58-0.95), whereas this was not observed in women. Unlike women, there was significant negative correlation between ALT levels and T2* values in men with H-NAFLD (r = -0.66, P = .01). Every 1-millisecond decrement in T2* value was associated with 6.37 IU/L increase in ALT level (95% CI, 1.8-10.9, P = .01) in men with H-NAFLD.

CONCLUSIONS

Higher hepatic iron in men with H-NAFLD, estimated by T2* mapping, may support the role of iron in possible progression of simple steatosis to nonalcoholic steatohepatitis. Lack of such correlation in women could be attributed to relatively lower iron storage or other mechanisms rather than iron.

Safety of biologic and nonbiologic disease-modifying antirheumatic drug therapy in veterans with rheumatoid arthritis and hepatitis B virus infection: a retrospective cohort study

Introduction

We evaluated the safety of current treatment regimens for patients with RA and HBV in a large US cohort.

Methods

We identified biologic and nonbiologic treatment episodes of RA patients using 1997 to 2011 national data from the US Veterans Health Administration. Eligible episodes had evidence of HBV infection (HBV surface antigen, HBV core antibody, HBV e-antibody and/or HBV DNA) and had a baseline alanine aminotransferase (ALT) <1.5 times the upper limit of laboratory normal within 90 days prior to initiation of a new biologic or nonbiologic DMARD. The main outcome of interest was hepatotoxicity, defined as ALT elevation >100 IU/mL. Results were reported as the cumulative incidence of treatment episodes achieving hepatotoxicity at 3, 6 and 12 months post biologic exposure.

Results

Five hundred sixty-six unique RA patients with HBV contributed 959 treatment episodes. Mean age was 62.1 ± 10.3 years; 91.8% were male. Hepatotoxicity was uncommon, with 26 events identified among 959 episodes (2.7%) within 12 months. Hepatotoxicity was comparable between biologic and nonbiologic DMARDs (2.6% vs. 2.8%, P = 0.87). The median time between HBV screening and starting a new RA drug was 504 days (IQR 144, 1,163). Follow-up HBV testing occurred among 14 hepatotoxicity episodes (53.8%) at a median of 202 days (IQR 82, 716) from the date of ALT elevation. A total of 146 (15.2%) treatment episodes received at least one test for HBV DNA at any point in the observation period.

Conclusions

Among US veterans with RA and HBV the risk of hepatotoxicity is low (2.7%), and comparable between biologic and nonbiologic DMARDS (2.8% vs. 2.6%, P = 0.87). HBV testing associated with DMARD initiation or hepatotoxicity was infrequent.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0628-z) contains supplementary material, which is available to authorized users.

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.

Liver function parameters in hip fracture patients: relations to age, adipokines, comorbidities and outcomes

AIM

To asses liver markers in older patients with hip fracture (HF) in relation to age, comorbidities, metabolic characteristics and short-term outcomes.

METHODS

In 294 patients with HF (mean age 82.0±7.9 years, 72.1% women) serum alanine aminotransferase (ALT), gammaglutamyltransferase (GGT), alkaline phosphatase (ALP), albumin, bilirubin, 25(OH)vitaminD, PTH, calcium, phosphate, magnesium, adiponectin, leptin, resistin, thyroid function and cardiac troponin I were measured.

RESULTS

Elevated ALT, GGT, ALP or bilirubin levels on admission were observed in 1.7%-9.9% of patients. With age GGT, ALT and leptin decrease, while PTH and adiponectin concentrations increase. Higher GGT (>30 U/L, median level) was associated with coronary artery disease (CAD), diabetes mellitus (DM), and alcohol overuse; lower ALT (≤20 U/L, median level) with dementia; total bilirubin>20 μmol/L with CAD and alcohol overuse; and albumin>33 g/L with CAD. Multivariate adjusted regression analyses revealed ALT, ALP, adiponectin, alcohol overuse and DM as independent and significant determinants of GGT (as continuous or categorical variable); GGT for each other liver marker; and PTH for adiponectin. The risk of prolonged hospital stay (>20 days) was about two times higher in patients with GGT>30 U/L or adiponectin>17.14 ng/L (median level) and 4.7 times higher if both conditions coexisted. The risk of in-hospital death was 3 times higher if albumin was <33 g/L.

CONCLUSIONS

In older HF patients liver markers even within the normal range are associated with age-related disorders and outcomes. Adiponectin (but not 25(OH)vitaminD, PTH, leptin or resistin) is an independent contributor to higher GGT. Serum GGT and albumin predict prolonged hospital stay and in-hospital death, respectively. A unifying hypothesis of the findings presented.

Upper limit of normal serum alanine aminotransferase levels in Japanese subjects

AIM

Serum alanine aminotransferase (ALT) is important for screening, diagnosis and management of chronic liver diseases. The incidence of non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH), which is considered a hepatic manifestation of lifestyle-related diseases, is increasing worldwide. However, the upper limit of the normal ALT level has not yet been established because of not excluding many lifestyle-related diseases. The aim of this study was to evaluate the upper limit of normal serum ALT levels in Japanese subjects.

METHODS

We analyzed the serum ALT levels of 11 404 Japanese subjects negative for hepatitis B surface antigen and hepatitis C virus antibody, and who received health check-ups. Lifestyle factors related to ALT levels were determined by multivariate analysis. Subjects with all factors identified by multivariate analysis within the normal range were defined as "healthy" subjects. The 90th percentile of ALT levels in healthy subjects was defined as the upper limit of normal ALT.

RESULTS

Whereas alcohol intake was not a significant factor, the following were independently associated with ALT concentration by multivariate analysis: sex; age; body mass index; waist circumference; concentrations of total cholesterol, high-density lipoprotein cholesterol, triglycerides and fasting blood glucose; and fatty liver on ultrasonography. Healthy subjects consisted of 1462 (21.2%) men and 2046 (45.4%) women, and the 90th percentiles of the ALT levels in the two groups were 29 and 23 IU/L, respectively.

CONCLUSION

The upper limits of normal ALT when considering lifestyle factors in Japanese subjects were 29 IU/L in men and 23 IU/L in women.

Impacts of common factors of life style on serum liver enzymes

AIM: To investigate the impacts of gender, age and factors of life style (alcohol, overweight, coffee and smoking) on serum liver enzymes.

METHODS: Serum alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) were measured from 6269 apparently healthy individuals (2851 men, 3418 women, mean age 45 ± 12 years, range 25-74 years) in a national cross-sectional health survey. All subjects underwent detailed clinical examinations and interviews including the amount and pattern of alcohol use, coffee consumption and smoking habits.

RESULTS: In this population with a mean ± SD alcohol consumption of 65 ± 105 g/wk and body mass index (BMI) of 26.1 ± 4.3 kg/m², both ALT and GGT were significantly influenced by alcohol use (P < 0.001) and BMI (P < 0.001), whereas smoking increased only GGT (P < 0.001). A significant effect of age on ALT was seen in men (P < 0.001) whereas not in women. Significant two-factor interactions of alcohol use in men were observed with age (ALT: P < 0.01; GGT: P < 0.001) and BMI (GGT: P < 0.05). For ALT, a significant interaction also occurred between BMI and age (P < 0.005). In contrast, women showed significant interactions of alcohol use with BMI (GGT: P < 0.05), smoking (GGT: P < 0.001), and coffee consumption (GGT: P < 0.001).

CONCLUSION: Life-style associated changes in liver enzymes may reflect health risks, which should be considered in the definition of normal limits for liver enzymes.

Comparison of hepatitis C virus testing strategies: birth cohort versus elevated alanine aminotransferase levels

BACKGROUND

Hepatitis C virus (HCV) infection is unidentified in an estimated 40%-85% of infected adults. Surveillance and modeling data have found significant increases in HCV-associated morbidity and mortality.

PURPOSE

To compare two HCV antibody (anti-HCV) testing strategies based on (1) elevated alanine aminotransferase levels (ALT) and (2) a birth cohort approach for people born during 1945-1965.

METHODS

Data from 19,055 adults aged 20-70 years who completed the National Health and Nutrition Examination Survey in 1999-2008 were analyzed in 2013. Two independent models were evaluated, based on membership in the 1945-1965 birth cohort or elevated ALT, to compare the number of identified anti-HCV-positive (anti-HCV+) individuals; proportion of total identified cases; and the number of people that would be tested using either strategy.

RESULTS

The prevalence of anti-HCV among adults aged 20-70 years was estimated at 2.0% (95% CI=1.8%, 2.3%), representing about 3.6 million people. The birth cohort strategy would result in testing about 85.4 million people and identifying nearly 2.8 million anti-HCV+ people with a sensitivity of 76.6%. The ALT strategy would test about 21.5 million adults and identify approximately 1.8 million anti-HCV+ people with a sensitivity of 50.0%. Implementing both strategies concurrently would identify 87.3% of anti-HCV+ adults.

CONCLUSIONS

The birth cohort strategy, which is recommended by both the CDC and the U.S. Preventive Services Task Force, would identify 1 million more anti-HCV+ people than the elevated ALT approach. Concurrent implementation would identify an even larger number of individuals ever infected.

Complex association between alanine aminotransferase activity and mortality in general population: a systematic review and meta-analysis of prospective studies

Objective

Controversy exists in using alanine aminotransferase (ALT) activity for predicting long-term survival. Therefore, this research study investigated the association between ALT activity and mortality through a systematic review and meta-analysis of previous prospective studies.

Methods

Electronic literature databases, including PubMed, Embase, and the Institute for Scientific Information (ISI), were searched for relevant prospective observational studies (published before Dec 30, 2013) on the association between baseline ALT activity and ensuing all-cause/disease-specific mortality. Information on nationality, sample size, participant characteristics, follow-up duration, comparison, outcome assessment, hazard ratios (HRs) and adjusted covariates was extracted. Pooled HRs and corresponding 95% confidence intervals (CIs) were separately calculated for categorical risk estimates (highest vs. lowest ALT categories) and continuous risk estimates (per 5 U/l of ALT increment) in subgroups separated by age (<70/≥70 years).

Results

A total of twelve prospective cohort studies, totaling 206,678 participants and 16,249 deaths, were identified and analyzed. In the younger age group, the pooled HR for mortality related to liver-disease was about 1.24 (95% CI: 1.23–1.25) per 5 U/l of ALT increment. The dose-response HRs of all-cause mortality, cardiovascular (CV) disease-related mortality, and cancer-related mortality were 0.91 (0.88–0.94), 0.91 (0.85–0.96), 0.92 (0.86–0.98) respectively per 5 U/l of ALT elevation, with insignificant heterogeneity in the older population. There was an approximate decrease of 4‰ observed on HRs of all-cause, CV-related, and cancer-related mortality followed with one year's increment through meta-regression (all P<0.05).

Conclusions

The ALT-mortality association was inconsistent and seems particularly susceptible to age after synthesizing the previous prospective studies. In terms of the age, ALT activity was more valuable in predicting mortality in the older population; extremely low ALT levels indicated a higher all-cause, CV-related, and cancer-related mortality. ALT activity may therefore be a useful biomarker when predicting the long-term survival of elderly patients.