Re-evaluation of serum alanine aminotransferase upper normal limit and its modulating factors in a large-scale population study

The association between frailty biomarkers and 20-year all-cause and cardiovascular mortality among community-dwelling older adults

OBJECTIVES

While several biomarkers were previously associated with frailty and mortality, data are still contradicting. We aimed to evaluate the association between novel biomarkers and frailty among community-dwelling older adults to enhance understanding of the pathophysiology of frailty.

METHODS

Nine hundred and sixty-three older adults were screened during the third phase (1999-2008) of the Israel study on Glucose Intolerance, Obesity, and Hypertension (GOH). Frailty was defined as sedentary individuals, past 10 years hospitalizations, or at least one of the following: body mass index (BMI) <21 kg/m2; albumin <3.2 g/dl; ≥2 major baseline diseases. Biomarkers were evaluated for their association with frailty, all-cause, and cardiovascular mortality.

RESULTS

Mean baseline age was 72 ± 7 years, 471 (49%) were women, and 195 (20%) were classified as frail. Median follow-up for cardiovascular and all-cause mortality was 11 and 13 years, with 179 (18.6%) and 466 (48.4%) deaths recorded, respectively. Multivariable logistic regression showed greater odds for frailty with lower quartile of alanine aminotransferase (ALT) (OR = 1.8, 95%CI: 1.2-2.8, p = 0.01), and for each 5 µmol/L increment in homocysteine levels (OR = 1.3, 95%CI: 1.1-1.5, p = 0.001). Multivariate Cox regression showed greater all-cause and cardiovascular mortality risk for individuals with low ALT (HR = 1.6, 95%CI: 1.3-2.0, p < 0.001 and HR = 1.5, 95% CI: 1.0-2.2, p = 0.03, respectively), and high homocysteine (HR = 1.1, 95%CI: 1.1-1.3, p = 0.003 and HR = 1.2, 95%CI: 1.0-1.3, p = 0.04, respectively). Homocysteine association with mortality was more pronounced in those with baseline ischemic heart disease (IHD) compared with subjects free of IHD (P for interaction = 0.01).

CONCLUSIONS

Lower ALT and higher homocysteine were associated with frailty, all-cause and cardiovascular mortality. These available and low-cost biomarkers underscore the nutritional and metabolic aspects of frailty when screening high-risk older adults, especially those with IHD, and may be considered as preferable screening biomarkers to be tested among these individuals for frailty and mortality risk.

Editorial: Redefining liver health-Personalised approach to assessment of serum ALT in clinical practice

This article is linked to Tan et al paper. To view this article, visit https://doi.org/10.1111/apt.17914

Updated Reference Intervals for Alanine Aminotransferase in a Metabolically and Histologically Normal Population

BACKGROUND & AIMS

This study aims to reevaluate upper reference limit (URL) for alanine aminotransferase (ALT) by considering the changing epidemiology of major liver diseases. We employed histological and metabolic parameters in Asian living liver donors.

METHODS

We performed a retrospective analysis of 5455 potential living liver donors from 2005 to 2019. Participants were screened for hepatitis B, C, HIV, and alcohol use. Histologically and metabolically healthy participants were assessed using the Prati criteria (body mass index <23 kg/m2, triglyceride ≤200 mg/dL, fasting glucose ≤105 mg/dL, total cholesterol ≤220 mg/dL). The updated ALT-URL was determined as the 95th percentile among participants without hepatic steatosis and who met the Prati criteria.

RESULTS

The median age was 30 years, with a male predominance (66.2%). Among 5455 participants, 3162 (58.0%) showed no hepatic steatosis, with 1553 (49.1%) meeting both the criteria for no steatosis and the Prati criteria for metabolic health. The updated URL for ALT in these participants was 34 U/L for males and 22 U/L for females, which was significantly lower than conventionally accepted values. Using this revised ALT-URL, 72.8% of males with ALT levels ≥34 U/L and 55.0% of females with ALT levels ≥22 U/L showed signs of steatosis, whereas 32.7% of males and 22.2% of females met the criteria for metabolic syndrome.

CONCLUSIONS

Our study provided the newly established reference intervals for ALT levels in a metabolically and histologically verified Asian population. The proposed URL for ALT are 34 U/L and 22 U/L for males and females, respectively.

Diagnostic significance of alanine aminotransferase isoenzymes in alcoholic and non-alcoholic fatty liver cancers

OBJECTIVES

Alanine aminotransferase (ALT) expression is highly elevated in the serum of patients with hepatocellular carcinoma. However, the role of ALT isoenzymes in the total ALT activity remains unclear. In the present study, we systematically investigated the role of ALT isoenzymes in alcoholic and non-alcoholic fatty liver cancer.

MATERIALS AND METHODS

The expression of ALT1 and ALT2 at the mRNA and protein levels in 25 paired primary liver cancer tissues was detected by reverse transcription quantitative PCR (RT-qPCR), Western blotting, and immunohistochemistry. Serum ALT activity was determined using an automated biochemical analyzer.

RESULTS

The mRNA and protein expression levels of ALT1 and ALT2 were lower in the tissues of alcoholic and non-alcoholic fatty liver cancers than in the paracancerous tissues. Notably, ALT2 was highly expressed in non-alcoholic fatty liver cancer tissues compared with alcoholic fatty liver cancer tissues. Total serum ALT activity was mainly contributed by ALT1 in alcoholic fatty liver cancer, whereas ALT1 contributed only marginally more to the total ALT activity than ALT2 in non-alcoholic fatty liver cancer. ALT2/ALT1 ratio can well discriminate normal control group, alcoholic liver cancer and non-alcoholic liver cancer.

CONCLUSION

ALT1 contributed more to the total ALT activity than ALT2 in both alcoholic and non-alcoholic fatty liver cancer. Serum ALT2 to ALT activity was higher in non-alcoholic fatty liver cancer than that in alcoholic fatty liver cancer. ALT2/ALT1 ratio has some diagnostic significance for alcoholic and non-alcoholic liver cancer.

Association of De Ritis Ratio with Prognosis in Patients with Coronary Artery Disease and Aminotransferase Activity within and outside the Healthy Values of Reference Range

BACKGROUND

The aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio (De Ritis ratio), obtained from AST and ALT activities in the healthy range, has not been studied in association with mortality.

METHODS

This study included 3392 patients with stable coronary heart disease and aminotransferase activity in the reference range. Patients are categorized into two groups: a group with AST and ALT activity in the healthy range (n = 1697), and a group with AST and/or ALT activity outside the healthy range but in the reference range (n = 1695). The primary endpoint was all-cause mortality at three years.

RESULTS

The De Ritis ratio (median 5th-95th percentile] was 0.94 [0.61-1.41] in patients with AST and ALT in the healthy range and 0.93 [0.45-1.96] in patients with AST and/or ALT outside the healthy range (p = 0.700). At three years, there were 86 deaths in patients with AST and ALT in the healthy range: 27 deaths (3.9%) in patients with a De Ritis ratio ≤median, and 59 deaths (8.2%) in patients with the De Ritis ratio >median (adjusted hazard ratio [HR] = 1.16, 95% confidence interval [CI] 0.94 to 1.42; p = 0.159); in patients with AST and/or ALT outside the healthy range, there were 148 deaths: 49 deaths (6.6%) in patients with a De Ritis ratio ≤median, and 99 deaths (14.1%) in patients with De Ritis ratio >median (adjusted HR = 1.27 [1.09-1.48], p = 0.002), with both HRs calculated per unit higher values of the De Ritis ratio.

CONCLUSIONS

The De Ritis ratio obtained from AST and ALT activity in the healthy range was not independently associated with higher risk of mortality. The De Ritis ratio obtained from aminotransferase activity outside the healthy range (but still in the reference range) was independently associated with the risk of mortality.

Observed Impact of Long-Term Consumption of Oral Cannabidiol on Liver Function in Healthy Adults

Introduction: Previous studies have suggested that prescribed cannabidiol (CBD) products may cause elevations in liver tests (LT). This study compared the prevalence of elevated LT in an adult population self-administering CBD with the normal and general adult population prevalences. Materials and Methods: Adults 18-75 years of age across the United States taking CBD orally for a minimum of 30 days were recruited from 12 individual CBD product companies in this decentralized, observational study and sent their standard CBD regimen from the company of their choice. An app-based, 21CFR Part 11 decentralized clinical study platform (ValidCare Study) was used to securely automate consent inclusion/exclusion criteria and collect all the data for this study, including: demographic information, medical history, reasons for taking, dosage, current medications dosage, adverse effects, and efficacy. At the end of 30 days, LTs were obtained. Follow-up LTs were offered to all individuals with elevated alanine transaminase (ALT) values. Results: A total of 28,121 individuals were invited to participate in this study, 1475 enrolled, and 839 (female: 65.3%, male: 34.7%) completed the study. Full-spectrum hemp oil was used by 55.7%, CBD-isolate by 40.5%, and broad spectrum by 3.8%. The mean±SD daily dose of CBD was 50.3+40.7 mg. The prevalence of elevated ALT was 9.1%, aspartate aminotransferase (AST) 4.0%, alkaline phosphatase 1.9%, total bilirubin 1.7%, with 85.5% of the ALT elevations <2×the upper limit of normal (ULN) with only 0.3% having ALT levels >3× ULN. The prevalence of ALT and AST elevations (9.1% and 4.0%) were not significantly different from known adult general population prevalences (8.9% and 4.9%). There was no significant association between CBD dosage and LT values. Thirty-three individuals with elevated ALT levels had follow-up LT performed with 21 having normal LT, 8 having the same severity of ALT elevation, and 4 having an increase in severity, 1 of which ultimately became normal. Conclusions: Self-medication of CBD does not appear to be associated with an increased prevalence of LT elevation and most of the LT elevations are likely due to the conditions/medications for which the individuals are taking CBD.

Updated upper limit of normal for serum alanine aminotransferase value in Vietnamese population

BACKGROUND

Alanine aminotransferase (ALT) is a marker of hepatic damage and its range can be affected by viral hepatitis, alcoholic hepatitis and non-alcoholic fatty liver diseases. We aimed to study the factors associated with higher ALT level and update the upper limit of normal (ULN) in the Vietnamese population.

METHODS

This cross-sectional study enrolled 8383 adults, aged 18 years and older who visited the Medical Center at Ho Chi Minh City for a health check-up. Following the exclusion criteria, 6677 subjects were included in the analysis.

RESULTS

Age ≤40 years, male gender, body mass index >23 kg/m2, diastolic blood pressure >85 mm Hg, cholesterol >5.2 mmol/L, triglyceride >1.7 mmol/L, positivity, anti-hepatitis C virus positivity and fatty liver (p<0.05) were associated with higher ALT level (>40 U/L). Without considering age and gender, healthy group is defined after exclusion of participants with one of the mentioned contributing factors. The median ALT level in the healthy group was 18 in men and 13 in women. The ULN at the 95th percentile of the healthy group was 40 U/L in men and 28 U/L in women.

CONCLUSION

The ULN for ALT in healthy women was lower than in healthy men. Updated ULN for ALT level can promote the identification of unhealthy subjects. More studies that involve ethnicity and lifestyle factors are needed to confirm the new ULN in the Vietnamese population.

Age Dependence of Liver Enzymes: An Analysis of Over 1,300,000 Consecutive Blood Samples

BACKGROUND & AIMS

Upper levels of normal for alanine aminotransferase (ALT), aspartate aminotransferase (AST), and γ-glutamyltransferase (GGT) generally take sex into account, but not age. This simplification may lead to misclassification and burden the patient and health system unnecessarily.

METHODS

Consecutive blood samples were analyzed from a German laboratory. Subcohorts included samples from a prescribed routine check-up and a healthy cohort, defined as patients without increased GGT, triglyceride, cholesterol, glycated hemoglobin, or glucose levels, and without known hepatitis B.

RESULTS

A total of 1,369,180 blood samples were analyzed from 601,779 participants (50.8% female; mean age, 58.5 y; SD, 18.0 y). There is an extreme age dependence in ALT values for men: increased values were seen in 20.0% (95% CI, 19.5%-20.4%) of patients in the age group of 25 to 34 years, but only 6.7% (95% CI, 6.4%-7.0%) for the ages of 65 to 74 years. The 95th percentile reaches values greater than 80 U/L instead of 50 U/L at the age of 35, and decrease to less than 50 U/L by the age of 75. Similar qualitative results were found in the healthy and prescribed routine check-up subcohorts. The age dependence is much weaker for ALT in women. The proportion of women with an increased AST level increases from approximately 6% to 12% at approximately age 50. The 95th percentile for GGT increases up to the age of 60 in men, and throughout life in women.

CONCLUSIONS

Current guidelines and reference values for ALT imply that subsequent diagnostics are needed for a large proportion of young men. Our data strongly suggest that age adaptation should be considered.

Incidental findings in UK healthy volunteers screened for a COVID-19 vaccine trial

The safety of novel therapeutics and vaccines are typically assessed in early phase clinical trials involving "healthy volunteers." Abnormalities in such individuals can be difficult to interpret and may indicate previously unrecognized medical conditions. The frequency of incidental findings (IFs) in healthy volunteers who attend for clinical trial screening is unclear. To assess this, we retrospectively analyzed data for 1838 "healthy volunteers" screened for enrolment in a UK multicenter, phase I/II severe acute respiratory syndrome-coronavirus 2 (SARS-COV-2) vaccine trial. Participants were predominantly White (89.7%, 1640/1828) with a median age of 34 years (interquartile range [IQR] = 27-44). There were 27.7% of participants (510/1838) who had at least one IF detected. The likelihood of identifying evidence of a potential, new blood-borne virus infection was low (1 in 238 participants) compared with identification of an elevated alanine transaminase (ALT; 1 in 17 participants). A large proportion of participants described social habits that could impact negatively on their health; 21% consumed alcohol in excess, 10% were current smokers, 11% described recreational drug use, and only 48% had body weight in the ideal range. Our data demonstrate that screening prior to enrollment in early phase clinical trials identifies a range of IFs, which should inform discussion during the consent process. Greater clarity is needed to ensure an appropriate balance is struck between early identification of medical problems and avoidance of exclusion of volunteers due to spurious or physiological abnormalities. Debate should inform the role of the trial physician in highlighting and advising about unhealthy social habits.

The liver in COVID-19: prevalence, patterns, predictors, and impact on outcomes of liver test abnormalities

BACKGROUND

Coronavirus disease 2019 (COVID-19) has caused a global pandemic unprecedented in over a century, with ≈35 million cases, and more than 1 million deaths globally. Though predominantly a lower respiratory illness, other organ injuries are well-recognized. Among these, liver injury is of major interest.

OBJECTIVE

To define prevalence, pattern, predictors, and impact of liver injury among patients hospitalized with COVID-19.

METHODS

Demographic, clinical, and biochemical data were collected retrospectively among patients admitted to St. Luke's University Hospital with COVID-19 between 1 March and 18 April 2020. Association of liver tests (LTs) with mortality and need for mechanical ventilation, adjusted for demographic, clinical and biochemical predictors, was examined.

RESULTS

Data were available on 551 patients. Prevalence of any or ≥3 × upper limit of normal transaminase elevation on was 61.2 and 9.4% on admission, and 72.1 and 22.4% at peak. Bilirubin and alkaline phosphatase elevations were less common on admission (11.4 and 12.6%, respectively), and at peak (17.7 and 22%, respectively). All liver test (LT) elevations were consistently predicted by inflammatory markers. Hyperbilirubinemia predicted mortality on admission and at peak. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) had opposite impact on mortality with AST positively, and ALT negatively associated with mortality. Hence, besides hyperbilirubinemia, AST:ALT ratio emerged as the best marker for mortality among the LTs.

CONCLUSION

LT elevations among patients presenting with COVID-19 are very common, though majority are mild. Admission and peak bilirubin ≥1 mg/dl, as well as admission and peak AST:ALT ratio were significant predictors of mortality, along with age, myocardial injury, and chronic medical illness.

Definition of Healthy Ranges for Alanine Aminotransferase Levels: A 2021 Update

The changing epidemiology of liver disease, and modifications in the recommended analytical methodology call for a re-evaluation of the upper reference limits (URLs) of alanine aminotransferase (ALT) levels. Using the same approach consolidated 20 years ago to define the healthy population, we defined the URL for the newly recommended International Federation of Clinical Chemistry (IFCC) standardized test. In a cross-sectional study, we examined 21,296 apparently healthy blood donors (age 18-65 years) and calculated the sex-specific URL by the 95th percentile in individuals without risk factors for liver disease. These were tested for the ability to predict liver damage in a subset of 745 participants with dysmetabolism, in an independent cohort of 977 unselected donors, and in 899 patients with chronic liver disease. ALT levels were measured by the IFCC test. Male sex, body mass index, glucose, lipids, ferritin, hypertension, and younger age were independent ALT predictors (P < 0.001). Updated URLs were identified at 42/30 U/L in males/females, approximately 30% lower than those currently recommended by the IFCC. Due to improved sensitivity, they conferred the ability to detect steatosis and significant fibrosis in individuals with dysmetabolism (odds ratio [OR] = 2.31, range 1.40-3.80, P = 0.001; and OR = 3.35, range 1.19-9.42, P = 0.021; respectively), although with a limited accuracy, and significant fibrosis in unselected donors (OR = 2.32, 1.02-5.31, P = 0.045). Updated URLs had a moderate to high accuracy to discriminate liver conditions (area under the receiver operating characteristic curve = 0.81, range 0.78-0.91). Conclusion: Updated URLs by the IFCC method were lower than those calculated in initial studies, but higher than those in use with the recommended old, nonstandardized method, and were able to better predict liver disease. The limited awareness that different techniques are still in use should be regarded as a possible source of medical errors.

Consensus Guidelines: Best Practices for Detection, Assessment and Management of Suspected Acute Drug-Induced Liver Injury During Clinical Trials in Adults with Chronic Viral Hepatitis and Adults with Cirrhosis Secondary to Hepatitis B, C and Nonalcoholic Steatohepatitis

With the widespread development of new drugs to treat chronic liver diseases (CLDs), including viral hepatitis and nonalcoholic steatohepatitis (NASH), more patients are entering trials with abnormal baseline liver tests and with advanced liver injury, including cirrhosis. The current regulatory guidelines addressing the monitoring, diagnosis, and management of suspected drug-induced liver injury (DILI) during clinical trials primarily address individuals entering with normal baseline liver tests. Using the same laboratory criteria cited as signals of potential DILI in studies involving patients with no underlying liver disease and normal baseline liver tests may result in premature and unnecessary cessation of a study drug in a clinical trial population whose abnormal and fluctuating liver tests are actually due to their underlying CLD. This position paper focuses on defining best practices for the detection, monitoring, diagnosis, and management of suspected acute DILI during clinical trials in patients with CLD, including hepatitis C virus (HCV) and hepatitis B virus (HBV), both with and without cirrhosis and NASH with cirrhosis. This is one of several position papers developed by the IQ DILI Initiative, comprising members from 16 pharmaceutical companies in collaboration with DILI experts from academia and regulatory agencies. It is based on an extensive literature review and discussions between industry members and experts from outside industry to achieve consensus regarding the recommendations. Key conclusions and recommendations include (1) the importance of establishing laboratory criteria that signal potential DILI events and that fit the disease indication being studied in the clinical trial based on knowledge of the natural history of test fluctuations in that disease; (2) establishing a pretreatment value that is based on more than one screening determination, and revising that baseline during the trial if a new nadir is achieved during treatment; (3) basing rules for increased monitoring and for stopping drug for potential DILI on multiples of baseline liver test values and/or a threshold value rather than multiples of the upper limit of normal (ULN) for that test; (4) making use of more sensitive tests of liver function, including direct bilirubin (DB) or combined parameters such as aspartate transaminase:alanine transaminase (AST:ALT) ratio or model for end-stage liver disease (MELD) to signal potential DILI, especially in studies of patients with cirrhosis; and (5) being aware of potential confounders related to complications of the disease being studied that may masquerade as DILI events.

Short-term laboratory and related safety outcomes for the multiple sclerosis oral disease-modifying therapies: an observational study

BACKGROUND

Real-world safety data for the oral multiple sclerosis (MS) disease-modifying therapies (DMTs), dimethyl fumarate (DMF), fingolimod, and teriflunomide are important. We examined laboratory test abnormalities and adverse health conditions in new users.

METHODS

Linked laboratory and administrative health data were accessed for all persons with MS (PwMS) filling their first oral DMT prescription in two Canadian provinces. PwMS were followed from first prescription fill until discontinuation, death, emigration or study end. Proportions of PwMS, and incidence rates (IR)/100 person-years, were calculated for ≥1 event of elevated alanine aminotransferase (ALT) (>the upper limit of normal [ULN]; all DMTs), liver toxicity (ALT>3xULN; fingolimod); lymphopenia and proteinuria (DMF), and cardiac arrhythmia, hypertension and pneumonia (all DMTs).

RESULTS

Overall, 1,140 PwMS were followed for up to 2 years. De novo elevated alanine aminotransferase affected 13.2% (DMF), 12.4% (teriflunomide), and 30.0% (fingolimod) of users. Liver toxicity affected 2.8% of fingolimod, lymphopenia 3.1% of DMF, and proteinuria 2.9% of DMF users. The incidences of cardiac arrhythmia, pneumonia and hypertension ranged from <1 to 1.86/100 person-years depending on the DMT.

CONCLUSIONS

The short-term, real-world incidences of abnormal laboratory results or adverse events were consistent with the pivotal clinical trial findings. Longer-term safety data are still needed.

Upper Normal Limits of Serum Alanine Aminotransferase in Healthy Population: A Systematic Review

BACKGROUND

Measuring serum alanine aminotransferase (ALT) enzyme is a routine clinical test commonly used to evaluate abnormalities in the body in general, and in the liver function in particular. Higher ALT levels are associated with some metabolic disorders. The upper limit normal (ULN) is considered as a reliable threshold for the definition of high ALT.

OBJECTIVES:

To assess the existing evidence on the ULN for ALT in the general population.

DATA SOURCE:

PubMed (Medline), EMBASE, Scopus, and Web of Science (ISI) were searched using a specified search strategy.

ELIGIBILITY CRITERIA:

We collected documents published from 1980 to 2018 in the English language, focusing on human samples at the population level and extracted the data after qualitative evaluation.

METHODS

We conducted this study in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement. We used specific search terms and their combinations to find documents from relevant databases. We used a snowballing approach to find documents not captured in the main phase of the search. Two authors separately conducted the search, screened the articles, and selected documents that were qualified for data extraction based on the defined inclusion criteria. Finally, data extraction was conducted by two authors using PRISMA checklist. Reported ULNs for ALT and 95% confidence intervals (CIs) were documented in previously developed datasheets.

RESULTS

Out of 15242 studies, 47 articles were included for data extraction and analysis. Data were sparse and lacked the consistency to precisely estimate ULN for serum ALT. The ULN of ALT was significantly diverse across various geographical locations and sexes. The lowest value of ULN for ALT was 19 IU/L in Chinese children (age range: 7 to < 10 years), and the highest value of ULN for ALT was 55 IU/L in children from Ghana aged < 5 years.

LIMITATIONS:

The main limitation of the current systematic review was the scarcity of the reported measures for ULN of ALT.

CONCLUSION

Based on the results of the current systematic review, it is suggested that the normal range of ALT be redefined, but this redefinition should be done according to the localized data. In order to redefine the ULN for ALT, regional differences, methods used in ALT measurements, and ULN determination should be considered.

Revision of serum ALT upper limits of normal facilitates assessment of mild liver injury in obese children with non-alcoholic fatty liver disease

Background

The serum alanine aminotransferase (ALT) level is a critical parameter for evaluating liver injury in non‐alcoholic fatty liver disease (NAFLD). However, the currently accepted upper limits of normal (ULN) for serum ALT (ULN‐ALT) are debated, as they may be excessively high.

Methods

A total of 1638 children aged 6‐16 years, comprising 507 children with normal BMI (500 healthy children and 7 children with NAFLD), 199 overweight children, and 932 obese children, were included in the analysis. We re‐evaluated the ULN‐ALT in 500 healthy Chinese children using the 95th percentiles of serum ALT levels as revised ULN‐ALT. Fatty liver was identified by ultrasound examination.

Results

Significant positive correlations between serum ALT levels and body mass index (BMI) were detected in overweight boys (r = .399, P < .001), obese boys (r = .398, P < .001), and obese girls (r = .392, P < .001). The prevalence percentages of NAFLD were 93.6%, 75.8%, and 37.9% in obese boys with serum ALT levels of >50, 25‐50, and ≤25 U/L and were 81.6%, 67.9%, and 20.6% in obese girls with serum ALT levels of >40, 20‐40, and ≤20 U/L, respectively.

Conclusion

Serum ALT levels significantly correlated with abnormal BMI values in children, suggesting a rigorous BMI threshold is needed to establish the cutoffs for serum ULN‐ALT in children. Besides, the revised serum ULN‐ALT can uncover mild liver injury in obese children with NAFLD.

Low Alanine Aminotransferase Levels in the Elderly Population: Frailty, Disability, Sarcopenia, and Reduced Survival

Background

Although low alanine aminotransferase (ALT) levels have been associated with poor outcomes in the elderly population, the determinants subtending this association have been poorly explored. To gain insight into this topic, we analyzed data from a prospective population-based database (InCHIANTI study) in which frailty, disability, sarcopenia, and pyridoxine levels were systematically assessed.

Methods

Data are from 765 participants aged more than 65 years (mean age 75.3 years, women 61.8%), without chronic liver disease, malignancies, or alcohol abuse. Frailty was defined according to Fried criteria, sarcopenia through peripheral Quantitative-Computed-Tomography (lowest gender-specific tertile of the residuals of a linear regression of muscle mass from height and fat mass), and disability as self-reported need for help in at least one basic daily living activity. Associations of ALT with overall and cardiovascular mortality were assessed by Cox-models with time-dependent covariates.

Results

ALT activity was inversely associated with frailty, sarcopenia, disability, and pyridoxine deficiency; however, higher ALT was confirmed to be protective with respect of overall and cardiovascular mortality even in multiple-adjusted models including all these covariates (overall: hazard ratio [HR] 0.98 [0.96-1], p = .02; cardiovascular: 0.94 [0.9-0.98], p < .01). The association between ALT activity and mortality was nonlinear (J-shaped), and subjects in the lower quintiles of ALT levels showed a sharply increased overall and cardiovascular mortality.

Conclusions

These results suggest that reduced ALT levels in older individuals can be considered as a marker of frailty, disability, and sarcopenia, and as an independent predictor of adverse outcomes. The possible relationship between reduced ALT and impaired hepatic metabolic functions should be explored.

Risk Factors for Alanine Aminotransferase Elevations in a Prospective Cohort of HIV-Infected Tanzanian Adults Initiating Antiretroviral Therapy

INTRODUCTION

Serum alanine aminotransferase (ALT) elevations are common among HIV-infected patients on combination antiretroviral therapy (cART).

APPROACH

We conducted a prospective cohort study of 3023 HIV-infected Tanzanian adults initiating cART. We assessed risk factors for mild/moderate ALT elevations >40 IU/L and severe ALT elevations >200 IU/L.

RESULTS

We found that over a median follow-up of 32.5 months (interquartile range: 19.4-41.5), 44.8% of participants had at least 1 incident ALT elevation >40 IU/L of which 50.1% were persistent elevations. Risk factors for incident ALT elevation >40 IU/L included male sex, CD4 count <100 cells/μL, d4T+3TC+NVP cART, and triglycerides ≥150 mg/dL (P values <.05). Hepatitis B coinfection and alcohol consumption increased the risk of severe ALT elevations >200 IU/L (P values: <.05).

CONCLUSION

Incident mild and moderate ALT elevations are common among Tanzanians initiating cART, and the clinical and demographic information can identify patients at increased risk.

Redefining the Normal Values of Serum Aminotransferases in Healthy Indian Males

BACKGROUND

The normal range for Aspartate and Alanine Aminotransferases (AST and ALT) levels (<40 IU/L) were set in 1950s. Recent data from certain countries suggest lower levels of AST and ALT. Aim of the study was to redefine the normal values of aminotransferases in healthy Indian adults.

METHODOLOGY

In a cross sectional prospective study, 1002 blood donors were evaluated to isolate a healthy cohort. Four and 9 subjects positive for HBsAg and anti-Hepatitis C Virus (HCV) respectively and three females were excluded. 986 male subjects were evaluated for levels of serum aminotransferases.

RESULTS

Of total 986 subjects (Group I), 543 (55.1%) had fatty liver on ultrasound [15 (1.5%) alcoholic fatty liver and 528 (53.5%) Nonalcoholic Fatty Liver Disease (NAFLD)]. Median AST and ALT in total group (Group I) were 27.69 (Interquartile Range (IQR) 22.33-37.04) and 34.19 IU/L (IQR 23.12-54.87) and in NAFLD (Group II) were 35.67 (IQR -27.49-47.43) and 50.36 (IQR 37.70-76.58) IU/L. Of remaining 443 subjects without fatty liver, 288 had one or more components of metabolic syndrome. Out of 155 patients with no fatty liver and no component of metabolic syndrome (Group III), 103 subjects had normal Body Mass Index (BMI) and normal cholesterol and Low Density Lipoprotein (LDL) (Group III_B). Median AST and ALT in Group III_B were 22.56 (IQR 20.23-26.91) and 21.36 (IQR 17.49-27.21) U/L respectively with a 95th percentile of 34.28 and 36.57 U/L for AST and ALT, respectively.

CONCLUSION

Levels of AST and ALT in healthy men are lower than the conventional values in India.

An Assessment of Upper Limits of Normal for ALT and the Impact on Evaluating Natural Course of Chronic Hepatitis B Virus Infection in Chinese Children

BACKGROUND

The current upper limits of normal (ULN) for serum alanine aminotransferase (ALT) are increasingly challenged. We aimed to re-evaluate the ULN for ALT and assess the potential impact on the classification of natural course of chronic hepatitis B virus (HBV) infection in children.

METHODS

Laboratory data obtained from three hospitals in China were retrospectively analysed. In total, 2054 children with chronic HBV infection and 8149 healthy children at age ≤18 years were included in the study.

RESULTS

Age-specific and gender-specific ULNs for ALT, at averages of 30 U/L for boys and 24 U/L for girls, were calculated from the data of healthy children. Using the revised ULNs vs. the current ULNs (40-50 U/L), 31-60% vs. 9-17% of the 2054 HBV-infected children had an abnormal result as seen in their ALT baseline analysis, and the highest abnormality rate was seen in the infants. Data of 516 HBV-infected children were applied for the classification of clinical phase, 28.8% vs. 19.8% of the children were classified into the phases of hepatitis B e antigen (HBeAg-)positive/negative hepatitis. During a median follow-up of 62 months, 39 of 153 children underwent HBeAg seroconversion, whereas 3 of them had persistently "normal" ALT, according to the current ULN.

CONCLUSIONS

The revision of ULN for ALT in children substantially impacts the classification of the natural course of chronic HBV infection. Mild ALT fluctuation is common during the stage childhood, suggesting a need to rethink the current conceptions of immune tolerance and natural course of chronic HBV infection in the children.

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.

Sensitivity and Specificity of Biochemical Tests for Diagnosis of Intrahepatic Cholestasis of Pregnancy

BACKGROUND AND AIM

Intrahepatic cholestasis of pregnancy (ICP) is linked with increased risk of fetal complications. An accurate diagnostic test is needed to diagnose this disorder on time. We aimed to assess sensitivity and specificity of laboratory tests used for diagnosis of intrahepatic cholestasis of pregnancy and determine more reliable cut-off values of transaminases.

MATERIAL AND METHODS

Sixty one symptomatic patients with ICP and 29 healthy pregnant women were included in the retrospective analysis.

RESULTS

ICP patients had higher total bile acids (TBA) levels than healthy women (32 vs. 6; P < 0.0001) due to increase in cholic acid (CA) and chenodeoxycholic acid (CDCA). CA/CDCA ratio was significantly higher in ICP patients compared to healthy pregnant women (1.13 vs. 0.68; P < 0.00002). TBA, CA, CDCA and CA/CDCA ratio demonstrate the following sensitivity (94%, 96%, 89%, 71.9%) and specificity (63%, 63%, 59%, 79.3%, respectively) for ICP diagnosis. Lowering cut-off values for ALT (31 U/L) and AST (30 U/L) resulted only in minimal increase of sensitivity to 92.2% vs. 90.1% for ALT and to 92.2%, vs. 90.6% for AST.

CONCLUSION

The present study did not reveal any single specific and sensitive marker for reliable diagnosis of ICP. Establishment of lower cut-off values for transaminases activity might only minimally increase the accuracy of diagnosing ICP.

Association of Serum 25-hydroxyvitamin D Levels and Liver Enzymes in a Nationally Representative Sample of Iranian Adolescents: The Childhood and Adolescence Surveillance and Prevention of Adult Noncommunicable Disease Study

Background:

Hypovitaminosis D is highly prevalent and has several adverse health effects. This study aims to assess the relationship of serum concentrations of 25-hydroxyvitamin D (25[OH] D) and liver enzymes in adolescents.

Methods:

This population-based cross-sectional survey was conducted among a nationally representative multistage sample of 1095 adolescents (52% boys), aged 10–18 years, living in different provinces of Iran. Serum 25(OH)D concentration <30 ng/mL was considered as hypovitaminosis D, and liver enzymes (alanine aminotransaminase [ALT] and aspartate aminotransaminase [AST]) of >40 U/L was considered as high level. To determine the association between serum 25(OH)D categories and elevated levels of liver enzymes, multiple regression models and linear regression analysis were applied, after adjustment for potential confounders. Odds ratios (95% confidence interval) of serum 25(OH)D and elevated liver enzymes were assessed by logistic regression analysis.

Results:

Higher rates of Vitamin D deficiency were documented among individuals with increased levels of liver enzymes. Compared to boys, median of 25(OH)D was lower in girls with elevated levels of liver function tests (12.75 vs. 25.60 ng/mL for ALT and 13 vs. 14.10 ng/mL for AST), with marginally significant gender differences regarding AST.

Conclusions:

We found a relatively high frequency of hypovitaminosis D among adolescents with abnormal liver function. Further prospective studies are needed to examine these associations from early life.

Factors Associated With Persistent Increase in Level of Alanine Aminotransferase in Patients With Chronic Hepatitis B Receiving Oral Antiviral Therapy

BACKGROUND & AIMS

Despite complete suppression of viral DNA with antiviral agents, in some patients with chronic hepatitis B (CHB), serum levels of alanine aminotransferase (ALT) do not normalize. We investigated factors associated with persistent increases in ALT level in patients with CHB given long-term tenofovir disoproxil fumarate.

METHODS

We analyzed data from 471 hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients with CHB participating in 2 phase 3 trials. We identified patients with an increased level of ALT (above the upper limit of normal range) after 5 years (240 weeks) of tenofovir disoproxil fumarate therapy. We analyzed findings from liver biopsy specimens collected from 467 patients (99%) at baseline and 339 patients (72%) at year 5 of treatment; biopsy specimens were evaluated by an independent pathologist. We performed stepwise, forward, multivariate regression analyses of specified baseline characteristics and on-treatment response parameters to identify factors associated with persistent increases in ALT level.

RESULTS

Of the 471 patients, 87 (18%) still had an increased ALT level at year 5 of treatment. Factors associated significantly with a persistent increase in ALT level were a steatosis score of 5% or greater (grade 1 or more) at baseline (odds ratio [OR], 2.236; 95% confidence interval [CI], 1.031-4.852; P = .042) and at year 5 (OR, 3.392; 95% CI, 1.560 ≥ 7.375; P = .002), HBeAg seropositivity at baseline (OR, 3.297; 95% CI, 1.653-6.576; P < .001), and age 40 years or older (OR, 2.099; 95% CI, 1.014-4.342; P = .046). Of the 42 HBeAg-positive patients with steatosis at baseline, 21 (50%) had an increased ALT level at year 5 of treatment. Patients with persistent increases in ALT level were more likely to have an increase in steatosis at year 5 than those with a normal ALT level.

CONCLUSIONS

HBeAg seropositivity and hepatic steatosis contribute to persistent increases in ALT level in patients with CHB receiving suppressive antiviral treatment. ClinicalTrials.gov registration numbers: NCT00117676 and NCT00116805.

Current role of transient elastography in the management of chronic hepatitis B patients

Liver fibrosis is an important prognostic factor for chronic hepatitis B (CHB), and accurate evaluation of the stage of liver fibrosis is crucial in establishing management strategies. While liver biopsy is still considered the gold standard for staging liver fibrosis or cirrhosis, transient elastography (TE), a noninvasive means of assessing liver fibrosis, has come to play an increasing role in this process. After extensive validation, TE is now regarded as a reliable surrogate maker for grading the severity of liver fibrosis in CHB patients. It can detect the extent of fibrosis in a patient and can also be used to evaluate longitudinal changes in liver fibrosis over time with or without interventional management, such as antiviral therapy. However, several confounders hinder the effective assessment of liver fibrosis using TE, such as extensive liver necroinflammation, hepatic congestion, and cholestasis. TE has limited use in obese patients or patients with ascites. Although TE has several limitations, due to its accessibility and safety, it is a valuable tool for the initial evaluation and follow-up in patients with CHB.

The association between the serum levels of uric acid and alanine aminotransferase in a population-based cohort

BACKGROUND & AIMS

Elevated serum uric acid levels reflect and also cause both oxidative stress and insulin resistance and are frequently observed in patients with the metabolic syndrome. A strong association exists between the metabolic syndrome and non-alcoholic fatty liver disease (NAFLD). Therefore, we aimed to test the association between uric acid and elevated alanine aminotransferase (ALT), as a surrogate for NAFLD, using real-world data.

METHODS

Data used for the cross-sectional study were obtained from Maccabi Healthcare System, a 2-million member health maintenance organization in Israel. The population consisted of individuals aged 20-60 years who underwent blood tests for ALT and uric acid between 1997 and 2012. Individuals with secondary liver disease, celiac, and inflammatory bowel-disease were excluded. Subgroup analysis was performed in subjects who were given the diagnosis of fatty liver in their medical records (n = 2628).

RESULTS

The study population included 82,608 people (32.5% men, mean age 43.91 ± 10.15 years). There was a significant positive dose-response association between serum uric acid levels and the rate of elevated serum ALT (P for trend <0.001). In multivariable model, controlling for potential confounders, the association between uric acid and elevated ALT persisted (OR = 2.10, 95% CI 1.93-2.29, for the fourth quartile vs. the first). This association was maintained in all categories of gender and BMI. Similar results were observed among patients diagnosed with fatty liver (OR = 1.77, 1.22-2.57).

CONCLUSIONS

Serum uric acid is independently associated with elevated ALT, as a surrogate for NAFLD, and thus may serve as a serum marker for liver damage and should be further investigated as a risk factor for NAFLD.

A Treatment Algorithm for the Management of Chronic Hepatitis B Virus Infection in the United States: 2015 Update

Chronic hepatitis B (CHB) continues to be an important public health problem worldwide, including in the United States. An algorithm for managing CHB was developed by a panel of United States hepatologists in 2004 and subsequently updated in 2006 and 2008. Since 2008, additional data on long-term safety and efficacy of licensed therapies have become available and have better defined therapeutic options for CHB. The evidence indicates that potent antiviral therapy can lead to regression of extensive fibrosis or even cirrhosis, thus potentially altering the natural history of CHB. In addition, appropriate choice of antiviral agent can minimize the risk of resistance. This updated algorithm for managing CHB is based primarily on evidence from the scientific literature. Where data were lacking, the panel relied on clinical experience and consensus expert opinion. The primary aim of antiviral therapy for CHB is durable suppression of serum hepatitis B virus (HBV) DNA to low or undetectable levels. CHB patients who have HBV DNA >2000 IU/mL, elevated alanine aminotransferase level, and any degree of fibrosis should receive antiviral therapy regardless of their hepatitis B e antigen status. CHB patients with HBV DNA >2000 IU/mL and elevated alanine aminotransferase level but no evidence of fibrosis may also be considered for antiviral therapy. Approved antiviral therapies for CHB are interferon alfa-2b, peginterferon alfa-2a, lamivudine, adefovir, entecavir, telbivudine, and tenofovir, although the preferred first-line treatment choices are peginterferon alfa-2a, entecavir, and tenofovir. In determining choice of therapy, considerations include efficacy, safety, rate of resistance, method of administration, duration, and cost.

Alanine transferase: An independent indicator of adiposity related comorbidity risk in youth

BACKGROUND

Elevated levels of alanine aminotransferase (ALT) are associated with obesity and are often a consequence of non-alcoholic fatty liver disease (NAFLD). The aim of the present study was to assess the relationship between ALT and risk factors for adiposity-related co-morbidities in a diverse population of middle school children.

METHODS

We measured height, weight, body fatness (bioelectrical impedance), waist circumference, insulin sensitivity, phase 1 insulin release (acute insulin response following intravenous glucose), beta-cell function (acute insulin response corrected for insulin sensitivity), ALT, lipid profiles, and circulating concentrations of interleukin-6 (IL-6), C-reactive protein, adiponectin, and tumor necrosis factor-α (TNF-α) in a multi-ethnic/racial population of 106 middle school students (aged 11-14 years, 45 female) of varying body mass indexes (BMI).

RESULTS

Alanine aminotransferase was significantly correlated with BMI, % body fat, fat mass, waist circumference, fasting insulin, insulin resistance, triglycerides, and was inversely correlated with high-density lipoprotein cholesterol in children, even though all values of ALT were "normal" (range of 4.0-33.0 U/L). ALT was significantly higher in males than females even when corrected for body fatness. Significant correlations with lipids and insulin resistance persisted even when adjusted for age, gender, and body fatness.

CONCLUSION

Even within the normative range, ALT levels were significantly correlated with anthropomorphic and biochemical risk factors for adiposity-related co-morbidities in youth. Therefore, because ALT is correlated with dyslipidemia, insulin resistance, and central fat distribution, it might also serve as a marker of risk for adiposity-related co-morbidities beyond NAFLD.

Drug-Induced Liver Injury Is a Major Risk for New Drugs

Drug-induced liver injury (DILI), a relatively rare condition, is nevertheless a major reason for not approving a drug in development or for removing one already marketed. With a specific diagnostic biomarker lacking, finding elevated serum enzyme [alanine aminotransferase (ALT), aspartate aminotransferase and alkaline phosphatase] activities remains an initial signal for incipient liver injury. Enzyme elevations alone may not be harmful, but if caused by a drug and followed by jaundice (called 'Hy's law') there is a high possibility of serious DILI. In 1997 several drugs were approved by the Food and Drug Administration (FDA) of the USA that were later withdrawn from the market for serious liver toxicity. New drugs in development are now required to be monitored for liver injury, and the data is to be considered in the approval decision. A program called e-DISH (evaluation of drug-induced serious hepatotoxicity) was introduced in 2004 to aid medical reviewers to select from all subjects studied those few who show nontrivial liver injury and estimate the most likely cause. The threshold of enzyme elevation comprising a warning for possibly serious DILI is uncertain, although generally accepted as 3-5 times the 'upper limit of normal'. The new direct-acting antiviral agents for treating chronic hepatitis C virus, which often lead to a reduction of elevated ALTs, mandate that a later increase without viral breakthrough be compared to the new on-treatment level of values. The drug may be discontinued or interrupted for evaluation to exclude other possible causes of liver injury. The FDA has approved no drug since 1997 that has been withdrawn later because of serious hepatotoxicity.

Impact of elevated aspartate and alanine aminotransferase on metabolic syndrome and its components among adult people living in Ningxia, China

OBJECTIVE

Metabolic syndrome (MS) is a combination of medical disorders that increase the risk for cardiovascular disease and diabetes mellitus. It suggests an association between an elevated serum aminotransferase level and MS. Little data show the relationship between the levels of serum aminotransferase and the incidence of MS in Ningxia, China.

METHODS

A total of 5415 subjects who received medical health checkups from 2007 to 2009 were enrolled in the study. The participants were interviewed by trained health workers under a structured questionnaire. MS was defined according to the modified ATPIII criteria for Asian Americans by the American Heart Association (AHA-ATP III).

RESULTS

The prevalence of elevated aspartate aminotransferase (AST) and ALT (>40 U/L) were 7.1% and 22.2% in males, and 2.1% and 4.8% in females respectively. The prevalence of MS was 32.1% in males and 15.4% in females. The components of MS were significantly more in the group with elevated aminotransferase levels than in the group with normal aminotransferase levels. The odds ratios (95% CI) for elevated AST were 1.90 (1.49, 2.42), 2.59 (2.01, 3.39), 1.68 (1.32, 2.15), and 1.81 (1.36, 2.42) in the adults with abdominal obesity, high serum triglycerides levels, high blood pressure, and high plasma glucose levels respectively. After adjustment for age, the odds ratios (95% CI) for elevated ALT were 3.08 (2.63, 3.61), 4.30 (3.64, 5.08), 1.26 (1.08, 1.48), 2.16 (1.93, 2.65) and 2.38 (1.96, 2.87) in adults with abdominal obesity, high serum triglycerides levels, low serum high-density lipoproteincholesterol (HDL-C), high blood pressure, and high plasma glucose levels respectively. The odds ratios (95% CI) for elevated AST were 1.67 (1.06, 2.63), 2.28 (1.46, 3.63), 2.59 (1.59, 4.21) and for elevated ALT 2.02 (1.50, 2.73), 2.68 (1.96, 3.65), 3.94 (2.86, 5.43) for the subjects with 1, 2, and ≥3 risk factors after adjustment for age, gender, and BMI.

CONCLUSION

The serum aminotransferase levels were higher in males compared to females, and serum ALT level was more closely associated with MS than the AST level in adults in Ningxia, China. With an increasing the number of components of MS, the aminotransferase levels and the risks for elevated aminotransferase increase, whereas the AST/ALT ratios decrease.

Estimation of normal values of serum transaminases based on liver histology in healthy Asian Indians

BACKGROUND AND AIM

Liver biopsy-based studies have shown that serum levels of aminotransferases are lower than conventional cut-off of 40 IU/mL in persons with normal histology. There is no such study in Indian population based on liver histology. This study aims to estimate normal values of serum aminotransferases in healthy Indian population with normal liver histology.

METHODS

This retrospective study includes all liver donors who underwent liver donation at our centre and had a preoperative liver biopsy done for various reasons. All the donors had negative viral markers. Nonalcoholic fatty liver (NAFL) was defined as > 5% hepatocytes having steatosis and no changes of steatohepatitis.

RESULTS

The study included 331 donors (147 males) with the ages of 35.7 ± 10.2 years. NAFL was present in 167 donors (50.4%). In comparison with male donors with normal histology (n = 67), donors with NAFL (n = 80) had significantly higher age, body mass index, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, gamma-glutamyl transpeptidase, total cholesterol, low-density lipoprotein, and fasting blood sugar. In comparison with female donors with normal histology, donors with NAFL had significantly higher body mass index, ALT, and triglycerides; however, there was no significant difference regarding other parameters. Of the AST and ALT in normal histology donors, 95th percentile were 33.8 IU/L and 38.6 IU/L for males and 31 IU/L and 35.2 IU/L for females. Twenty-five donors had lean NAFL (body mass index < 23 kg/m2).

CONCLUSION

Serum aminotransferase values in healthy Asian Indian population with normal histology are provided. Histological NAFL is present in half of apparently normal donors, and it has different clinical and biochemical associations in males and females.

Redefining the alanine aminotransferase upper limit of normal improves the prediction of metabolic syndrome risk

BACKGROUND

Multiple studies have recently proposed the lowering of upper limit of normal (ULN) for alanine aminotransferase (ALT) to improve the diagnostic sensitivity for viral hepatitides and metabolic syndrome (MS). We have tried to validate some of the proposed ULNs in the diagnosis of MS.

METHODS

We used data from the HepaMeta Study conducted in 2011 in Slovakia, which explored the prevalence of MS in eastern Slovakia. Patients were tested for the criteria of MS and ALT. Different, previously published, ALT cutoffs were then used to calculate odds' ratios, sensitivity, specificity, and accuracy of MS and its components.

RESULTS

Manufacturers' recommended ULN used in our institution (0.8 µkat/l, 47 U/l for men and 0.6 µkat/l, 35 U/l for women) failed to predict any significant risk of MS. Lowered cutoff (72% of the original ULN) identified the patients with the highest age-adjusted probability of MS (odds ratio 3.194, 95% confidence interval 1.398-7.295). ALT was significantly associated with elevated levels of triacylglycerols, hyperglycemia, and obesity.

CONCLUSION

In patients with MS, one must consider liver involvement if the patient has ALT levels in the upper third of the reference range. There is the need for discussion about the feasibility of lower ALT ULN in clinical practice.

Determination of the upper cut-off values of serum alanine aminotransferase and aspartate aminotransferase in Chinese

AIM: To determine the upper cut-off values of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in a Northern Chinese population.

METHODS: A total of 3769 subjects in Jilin Province Northeast China were stratified to determine the potential factors affecting serum ALT and AST levels. The upper cut-off values of serum ALT and AST in these subjects were determined using receiver operating characteristic analysis and their sensitivity and specificity were evaluated.

RESULTS: Stratification analysis revealed that serum ALT and AST levels were associated with gender, alcohol consumption, serum cholesterol and triglyceride levels, and body mass index. The upper cut-off values of serum ALT and AST were 22.15 U/L and 25.35 U/L for healthy men and 22.40 U/L and 24.25 U/L for healthy women, respectively. The new cut-off values had a higher sensitivity, but a slightly lower specificity than the current standards.

CONCLUSION: Our results indicate that the new upper cut-off values of serum ALT and AST are markedly lower than current standards and may be valuable for the evaluation of liver function.

Development of non-alcoholic fatty liver disease scoring system among adult medical check-up patients: a large cross-sectional and prospective validation study

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the community. However, NAFLD remains undiagnosed in most people with limited access to imaging facilities in most developing countries.

OBJECTIVE

To examine the prevalence of NAFLD and to develop the risk scoring model for predicting the presence of NAFLD among adult medical check-up patients.

METHOD

A large prospective cross-sectional study was conducted among medical check-up patients who underwent transabdominal ultrasound examination between January and December 2013 in Medistra Hospital, Jakarta. Data were obtained from the patients' medical records. Logistic regression analyses were undertaken to identify the best combination of risk factors for predicting fatty liver using the backward (likelihood ratio) approach. The adjusted odds ratio and 95% confidence interval were estimated using the logistic regression coefficient. The prediction model was assessed using the receiver operating characteristic curve and the Hosmer-Lemeshow goodness-of-fit test and was validated on a new, prospective cohort. Statistical analysis was done using SPSS version 17.

RESULTS

A total of 1,054 cases was included in this study. Fatty liver was present in 538 (51.0%) patients. Bivariate analyses found associations among fatty liver and several risk factors. Six risk factors were incorporated to build the final prediction model. All scores were summed up to obtain the total score. A probability equation was developed by applying linear regression analysis on the total score. The prediction model had good diagnostic performance with an area under the receiver operating characteristic curve =0.833 (95% confidence interval =0.809-0.857). The Hosmer-Lemeshow goodness-of-fit P-value was 0.232, which indicated the appropriateness of the logistic regression model to predict fatty liver. On the validation set, the scoring system proved to be moderately accurate and can potentially be applied to larger population setting.

CONCLUSION

The presence of fatty liver in NAFLD patients can be predicted using our proposed fatty liver scoring system.

Determinants of alanine aminotransferase levels in a large population from Southern Italy: relationship between alanine aminotransferase and age

BACKGROUND

Determinants of alanine aminotransferase levels have never been investigated in real-life settings. The relationship between alanine aminotransferase and age remains controversial. We evaluated epidemiological, anthropometric, and metabolic factors associated with alanine aminotransferase, focusing on the relationship between alanine aminotransferase and age.

METHODS

A 5-year retrospective analysis was performed on data recorded by 120 general practitioners from Naples (Italy), caring for 170,000 subjects. Exclusion criteria were age <18 years, diagnosis of chronic liver disease, positive markers for viral hepatitis, alcohol abuse, and alanine aminotransferase >100UI/L.

RESULTS

44,232 subjects were enrolled (42.7% males, mean age 56±18 years). Alanine aminotransferase showed independent direct associations with body mass index, glycaemia, cholesterol, and triglycerides (p<0.001), and inverse associations with high-density lipoprotein cholesterol (p<0.001) and creatinine (p<0.01). The relationship between alanine aminotransferase and age was better expressed by polynomial regression (r=0.18, p<0.001), creating an inverted parabola. Mean alanine aminotransferase increased until the third decade in males and the fifth in females, with a subsequent progressive decrease in both genders. The inverse association between alanine aminotransferase and age in older subjects was independent from metabolic factors.

CONCLUSIONS

This real-life setting study, supports the concept that dysmetabolism is a strong determinant of liver injury. Based on our data, a reduction of the standard upper limit of normal alanine aminotransferase should be considered for older subjects.

Keratin-18 and microRNA-122 complement alanine aminotransferase as novel safety biomarkers for drug-induced liver injury in two human cohorts

BACKGROUND & AIMS

There is a demand for more sensitive, specific and predictive biomarkers for drug-induced liver injury (DILI) than the gold standard used today, alanine aminotransferase (ALT). The aim of this study was to qualify novel DILI biomarkers (keratin-18 markers M65/M30, microRNA-122, glutamate dehydrogenase and alpha-foetoprotein) in human DILI.

METHODS

Levels of the novel biomarkers were measured by enzyme-linked immunosorbent assay or real-time quantitative reverse-transcription PCR (qRT-PCR) in two human DILI cohorts: a human volunteer study with acetaminophen and a human immunodeficiency virus (HIV)/tuberculosis (TB) study.

RESULTS

In the acetaminophen study, serum M65 and microRNA-122 levels were significantly increased at an earlier time point than ALT. Furthermore, the maximal elevation of M65 and microRNA-122 exceeded the increase in ALT. In the HIV/TB study, all the analysed novel biomarkers increased after 1 week of treatment. In contrast to ALT, the novel biomarkers remained stable in a human cohort with exercise-induced muscular injury.

CONCLUSIONS

M65 and microRNA-122 are potential biomarkers of DILI superior to ALT with respect to sensitivity and specificity.

Systematic review with meta-analysis: the proportion of chronic hepatitis B patients with normal alanine transaminase ≤ 40 IU/L and significant hepatic fibrosis

BACKGROUND

Chronic hepatitis B (CHB) may lead to cirrhosis, hepatocellular carcinoma and premature death. Elevated alanine transaminase (ALT) levels ≥ the upper limit of normal (ULN) are a major determinant for initiating anti-viral therapy; however, ALT levels alone may not be predictive of hepatic fibrosis.

AIM

To determine the proportion of CHB patients with ALT ≤ 40 IU/L and liver fibrosis stage ≥ 2. Secondary goals include subgroup analysis by hepatitis B e antigen (HBeAg) status, high hepatitis B virus (HBV) DNA levels, Asian ethnicity, lower ULN of ≤ 30 IU/L (males) and 19 IU/L (females), and advanced age.

METHODS

Studies identified in EMBASE and MEDLINE (1/1990-6/2012) using the search criteria: "Hepatitis B"[Mesh] OR "Hepatitis B virus"[Mesh] OR "Hepatitis B, Chronic"[Mesh])) AND "Alanine Transaminase"[Mesh]) and abstracts containing the term 'hepatitis' from recent major U.S. gastroenterology and liver society meetings were considered.

RESULTS

Among nine studies (N = 830 patients), a significant proportion (20.7%; 95% CI: 16.2-26.0%) of CHB patients with ALT levels ≤ 40 IU/L had significant fibrosis irrespective of HBeAg status, high HBV DNA levels, ethnicity or age, although this proportion may be higher in patients older than 30-40 years old. The corresponding proportion was 27.8% even when the newer ULN of 30 IU/L (males) and 19 IU/L (females) was applied.

CONCLUSIONS

Approximately one fifth of CHB patients with ALT ≤ 40 IU/L may have significant hepatic fibrosis. The approach to such patients should be individualised, as further evaluation and treatment may be appropriate.

Alanine aminotransferase-old biomarker and new concept: a review

Measurement of serum alanine aminotransferase (ALT) is a common, readily available, and inexpensive laboratory assay in clinical practice. ALT activity is not only measured to detect liver disease, but also to monitor overall health. ALT activity is influenced by various factors, including viral hepatitis, alcohol consumption, and medication. Recently, the impact of metabolic abnormalities on ALT variation has raised concern due to the worldwide obesity epidemic. The normal ranges for ALT have been updated and validated considering the metabolic covariates in the various ethnic districts. The interaction between metabolic and demographic factors on ALT variation has also been discussed in previous studies. In addition, an extremely low ALT value might reflect the process of aging, and frailty in older adults has been raised as another clinically significant feature of this enzyme, to be followed with additional epidemiologic investigation. Timely updated, comprehensive, and systematic introduction of ALT activity is necessary to aid clinicians make better use of this enzyme.

Elevated alanine aminotransferase independently predicts new onset of depression in employees undergoing health screening examinations

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of elevated alanine aminotransferase (ALT). NAFLD is associated with insulin resistance and hepatic inflammation. Similarly, patients with depression exhibit insulin resistance and increased inflammatory markers. However, no study has shown a clear association between elevated ALT and the development of depression. The aim of the study was to test whether elevated ALT, a surrogate marker for NAFLD, predicts the development of depression.

METHOD

The present prospective cohort study investigated 12 180 employed adults referred for health examinations that included fasting blood tests and anthropometric measurements between 2003 and 2010. Exclusion criteria were: baseline minor/major depression, excessive alcohol consumption and other causes for ALT elevation. Depression was evaluated by the eight-item Patient Health Questionnaire (PHQ-8) score.

RESULTS

The final cohort included 5984 subjects [69.4% men, aged 45.0 (s.d. = 10.24) years]. The incidence rate of minor and major depression was 3.8% and 1.4%, respectively. Elevated ALT was a significant independent predictor for the occurrence of minor [odds ratio (OR) 2.02, 95% confidence interval (CI) 1.40-2.92] and major (OR 3.132, 95% CI 1.81-5.40) depression after adjusting for age, gender, body mass index, education level, serum levels of lipids, glucose, smoking and physical activity. Adding subjective health and affective state parameters (sleep disturbances, self-rated health, anxiety and burnout) as potential mediators only slightly ameliorated the association. Persistently elevated ALT was associated with the greatest risk for minor or major depression as compared with elevation only at baseline or follow-up (p for trend < 0.001).

CONCLUSIONS

Elevated ALT was associated with developing depressive symptoms, thus suggesting that NAFLD may represent an independent modifiable risk factor for depression.

Lingmao Formula Combined with Entecavir for HBeAg-Positive Chronic Hepatitis B Patients with Mildly Elevated Alanine Aminotransferase: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

Objective. To determine the efficacy and safety of Lingmao Formula combined with entecavir for HBeAg-positive chronic hepatitis B patients with mildly elevated alanine aminotransferase (ALT). Methods. 301 patients were randomly assigned to receive Lingmao Formula combined with entecavir (treatment group) or placebo combined with entecavir (control group) for 52 weeks. The outcomes of interest included the reduction of serum HBV DNA level, HBeAg loss, HBeAg seroconversion, ALT normalization, and histological improvement. Results. The mean decrease of serum HBV DNA level from baseline and the percentage of patients who had reduction in serum HBV DNA level ≥2 lg copies/mL in treatment group were significantly greater than that in control group (5.5 versus 5.4 lg copies/mL, P = 0.010; 98.5% versus 92.6%, P = 0.019). The percentage of HBeAg loss in treatment group was 22.8%, which was much higher than a percentage of 12.6% in control group (P = 0.038). There was no significant difference between the two groups in histological improvement. Safety was similar in the two groups. Conclusions. The combination of Lingmao Formula with entecavir could result in significant decrease of serum HBV DNA and increase of HBeAg loss for HBeAg-positive chronic hepatitis B patients with mildly elevated ALT without any serious adverse events. Clinical trial registration number is ChiCTR-TRC-09000594.

Revising the upper limit of normal for levels of serum alanine aminotransferase in a Middle Eastern population with normal liver histology

BACKGROUND

Recently, the upper limits of normal (ULN) for alanine-aminotransferase (ALT) has been recommended to be lowered to ≤ 30 U/l in men and ≤ 19 U/l in women.

AIM

To evaluate the ALT concentrations in a healthy Middle Eastern population with biopsy-proven normal liver tissue.

METHODS

ALT values were calculated from 175 consecutive Saudi potential living liver donors who underwent a liver biopsy as part of a stepwise pretransplant workup.

RESULTS

The mean age of the 110 potential donors with normal liver histology was 27 ± 6.2 years for men and 38.6 ± 7.1 years for women. The mean body mass index (BMI) levels were 23.0 ± 3.5 kg/m(2) for men and 24.7 ± 3.25 kg/m(2) for women, and the ALT levels were higher in male patients (22.6 ± 9 vs. 16.4 U/l ± 8, p value = 0.003). Multivariate linear regression showed that BMI and sex were independent variables that were positively associated with the levels of ALT (p < 0.0001). Moreover, when we analyzed donors according to the Prati criteria, 63 (36.0 %) of the individuals were classified into this subgroup. The mean ALT concentration was 12.9 U/l ± 4.5 in women and 19.7 U/l ± 6.9 in men, and these values were significantly lower than those obtained from subjects who did not fit the Prati criteria (19.4 U/l ± 1.8, p = 0.04 for women and 29.0 U/l ± 12.1, p = <0.0001 for men). Thus, we calculated healthy ALT values of 33 IU/l for men and 22 IU/l for women.

CONCLUSIONS

The ULN for ALT levels in Middle Eastern populations should be lowered, including separate values for males and females. Furthermore, metabolic parameters were shown to have a significant effect on ALT levels.

Determining the validity of hospital laboratory reference intervals for healthy young adults participating in early clinical trials of candidate vaccines

This was a retrospective study to determine the validity of institutional reference intervals for interpreting biochemistry and hematology results in healthy adults in the context of clinical trials of preventive vaccines. An example population of 974 healthy adults participating in clinical trials at the Jenner Institute, Oxford, UK, between 1999 and 2009 was studied. Methods for calculating the central 95% ranges and determining the coefficients of within person variation were demonstrated. Recommendations have been made as to how these data can be usefully applied to the interpretation of blood results in healthy adult subjects for the purposes of clinical trial inclusion decisions and post-vaccination safety monitoring.

Upper limit of normal for alanine aminotransferase: quo vadis?

Several studies suggest that a substantial number of patients with normal serum alanine aminotransferase (ALT) levels, defined by current thresholds, have ongoing hepatic necro-inflammation and fibrosis, and are at risk of liver disease progression. A major problem lies in the definition of normality. The current upper limit of normal (ULN) for ALT was established in the 1980s when reference populations were likely to include many persons with hepatitis C virus infection and nonalcoholic fatty liver disease. Because ALT may be influenced, not only by liver disease, but also by other medical conditions, changing lifestyle factors and demographic determinants, the current ALT ULN threshold has recently been challenged. This review not only highlights current evidence on why and how ALT ULN should be redefined, but also discusses the current concerns about updating the ULN threshold for ALT.

The relationship between DXA-based and anthropometric measures of visceral fat and morbidity in women

Background

Excess accumulation of visceral fat is a prominent risk factor for cardiovascular and metabolic morbidity. While computed tomography (CT) is the gold standard to measure visceral adiposity, this is often not possible for large studies - thus valid, but less expensive and intrusive proxy measures of visceral fat are required such as dual-energy X-ray absorptiometry (DXA). Study aims were to a) identify a valid DXA-based measure of visceral adipose tissue (VAT), b) estimate VAT heritability and c) assess visceral fat association with morbidity in relation to body fat distribution.

Methods

A validation sample of 54 females measured for detailed body fat composition - assessed using CT, DXA and anthropometry – was used to evaluate previously published predictive models of CT-measured visceral fat. Based upon a validated model, we realised an out-of-sample estimate of abdominal VAT area for a study sample of 3457 female volunteer twins and estimated VAT area heritability using a classical twin study design. Regression and residuals analyses were used to assess the relationship between adiposity and morbidity.

Results

Published models applied to the validation sample explained >80% of the variance in CT-measured visceral fat. While CT visceral fat was best estimated using a linear regression for waist circumference, CT body cavity area and total abdominal fat (R² = 0.91), anthropometric measures alone predicted VAT almost equally well (CT body cavity area and waist circumference, R² = 0.86). Narrow sense VAT area heritability for the study sample was estimated to be 58% (95% CI: 51-66%) with a shared familial component of 24% (17-30%). VAT area is strongly associated with type 2 diabetes (T2D), hypertension (HT), subclinical atherosclerosis and liver function tests. In particular, VAT area is associated with T2D, HT and liver function (alanine transaminase) independent of DXA total abdominal fat and body mass index (BMI).

Conclusions

DXA and anthropometric measures can be utilised to derive estimates of visceral fat as a reliable alternative to CT. Visceral fat is heritable and appears to mediate the association between body adiposity and morbidity. This observation is consistent with hypotheses that suggest excess visceral adiposity is causally related to cardiovascular and metabolic disease.

Upper limit of normal serum alanine and aspartate aminotransferase levels in Korea

BACKGROUND AND AIM

 The widely accepted range of upper limits of normal (ULN) alanine aminotransferase (ALT) levels (ULN < 40 U/L) was recently challenged by several reports. Both ALT and aspartate aminotransferase (AST) are commonly used as surrogate markers of liver disease, but almost all studies of aminotransferase activity were conducted on ALT. We investigated not only ULN of ALT but also AST activity and to identify factors modulating them in healthy Korean.

METHODS

A cross-sectional study of 411,240 registered blood donors in all nationwide blood banks belonging to the Korean Red Cross were conducted. ULN of ALT and AST was evaluated adjusting their age according to the national population census database. "Decision tree model" was used to identify the affecting factors of ALT and AST and optimal cut-off points of affecting factors.

RESULTS

 "ULN of ALT" was 34 U/L in men and 24 U/L in women and "ULN of AST" was 32 U/L in men and 26 U/L in women in the blood donor database. Decision tree analysis showed that ALT levels were mostly influenced by body mass index level and its critical two cut-off points were 23.5 kg/m2 and 25.8 kg/m2 , respectively. The most affecting factor of AST was gender.

CONCLUSION

Upper limits of normal of ALT and AST in Koreans were lower than conventional accepted values (< 40 U/L) but higher than recently suggested values (male < 30 U/L and female < 19 U/L). Body mass index was the most determining factor for ALT and gender was the most influencing factor for AST activity.