Gamma glutamyltransferase and metabolic syndrome risk: a systematic review and dose-response meta-analysis

Relationship between HECTD4 gene variants, obesity, and coffee consumption

BACKGROUND

In genome-wide association studies, the HECT domain E3 ubiquitin-protein ligase 4 (HECTD4) gene was suggested to be associated with obesity-related traits and coffee consumption. However, the association of genetic variants between coffee consumption and obesity has not been tested in Koreans. Therefore, we investigated whether HECTD4 gene variants act as effect modifiers on the relationship between obesity and coffee.

METHODS

This study analyzed the correlation between coffee consumption and obesity among 58,698 individuals representing the Health Examinees. Participants were categorized into obese (BMI ≥ 25.0 kg/m2) and nonobese (18.5 ≤ BMI < 23.0 kg/m2). Food consumption was assessed by a food frequency questionnaire.

RESULTS

We identified four HECTD4 gene variants associated with obesity-related traits and coffee consumption based on Bonferroni-corrected significance level (p < 0.00014). Furthermore, multivariate logistic regression analysis confirmed that the impact of coffee consumption on obesity differed based on the HECTD4 rs2074356 genotypes. A positive correlation between obesity and coffee consumption was observed, with a more pronounced effect in individuals with the G allele (OR = 1.61 for 1 to <2 cups/day, p = 1.89 × 10-37; OR = 1.82 for ≥2 cups/day, p = 1.73 × 10-42) than in those with the A allele (OR = 1.47 for 1 to <2 cups/day, p = 7.41 × 10-17; OR = 1.45 for ≥2 cups/day, p = 7.24 × 10-11).

CONCLUSION

Our findings suggest that the influence of coffee consumption on obesity may vary in Koreans depending on the HECTD4 gene variant.

Can Serum Gamma-Glutamyl Transferase Predict All-Cause Mortality in Hypertensive Patients?

Introduction In this investigation, the focus was on exploring the connection between serum gamma-glutamyl transferase (GGT), a vital element that influences health and mortality in relation to aging, and all-cause mortality. The study was conducted using a follow-up approach at eight- and 20-year intervals. Methods The study involved 1,101 female participants, with an average age of 69 years (± 9), and 916 male participants, with an average age of 67 years (± 11), who were all diagnosed with hypertension. These individuals were drawn from the Nomura cohort study, which consisted of two separate cohorts: the initial cohort established in 2002 and the subsequent cohort in 2014. We used a Cox proportional hazards model to calculate the hazard ratios (HRs), adjusted for multiple variables, for mortality risk from the initial health examination until the conclusion of the follow-up periods. Results The study followed the participants for a median period of 13.9 years (interquartile range: 8.5-20.2 years). During this follow-up period, 716 deaths were recorded in this population (360 in men and 356 in women), resulting in a mortality rate of 25.5 deaths per 1,000 person-years. Male participants categorized with serum GGT levels ranging from 42 to 86 IU/L showed a 64% increased risk of all-cause mortality (HR: 1.64; 95% confidence interval (CI): 1.11-2.40), while those with GGT levels of 87 IU/L or higher exhibited a 93% elevated risk (HR: 1.93; 95% CI: 1.18-3.16) compared to individuals with GGT levels below 19 IU/L. The association between higher GGT levels and increased all-cause mortality was more evident in men than in women, with a significant interaction between gender and baseline serum GGT (p = 0.020). Conclusions Our findings suggest a notable correlation between irregular GGT levels and the overall mortality rate among Japanese individuals with hypertension living in community settings. Notably, especially in older males, GGT activity turns out to be a critical biomarker for predicting long-term survival.

Gamma-glutamyl transpeptidase and indirect bilirubin may participate in systemic inflammation of patients with psoriatic arthritis

BACKGROUND

Previous studies have suggested that systemic metabolic abnormalities are closely related to psoriatic arthritis (PsA). Gamma-glutamyl transpeptidase (GGT) and indirect bilirubin (IBIL), two essential active substances in hepatic metabolism that have been demonstrated as an oxidative and anti-oxidative factor respectively, have been proved to be involved in oxidative stress damage and inflammation in several human diseases. However, their role in PsA remains unclear.

METHODS

In this retrospective comparative cohort study, a case group of 68 PsA patients and a control group of 73 healthy volunteers from the Third Hospital of Hebei Medical University were enrolled. Serum GGT, IBIL, GGT/IBIL ratio and C-reactive protein (CRP), a well applied bio-marker of systemic inflammatory in PsA, were compared between the two groups. Furthermore, the relationship of GGT, IBIL and GGT/IBIL with CRP were explored in PsA patients. Finally, the patients were divided into high inflammation group and low inflammation group according to the median value of CRP. Multivariate logistic regression analyses were used for the association of systemic inflammation level with GGT, IBIL and GGT/IBIL.

RESULTS

Compared with healthy controls, PsA patients exhibited significantly higher serum GGT, GGT/IBIL, and CRP levels and lower IBIL levels. Serum GGT and GGT/IBIL were positively correlated with CRP, whereas IBIL were negatively correlated with CRP. Binary logistic regression analysis revealed that serum GGT was a risk factor for high CRP in PsA, whereas IBIL was a protective factor. Furthermore, GGT/IBIL was a better indicator of high CRP condition in PsA patients than either GGT or IBIL alone, as determined by the receiver operating characteristic curves.

CONCLUSION

GGT and IBIL may participate in the pathogenesis of PsA. Additionally, GGT, IBIL and the balance of the two may reflect systemic inflammation mediated by oxidative stress events related to metabolic abnormalities to a certain extent.

Metabolic syndrome and transaminases: systematic review and meta-analysis

BACKGROUND

Metabolic syndrome (MetS) is a group of metabolic abnormalities characterised by hypertension, central obesity, dyslipidaemia and dysregulation of blood glucose, associated with the risk of diabetes, cardiovascular disease and overall mortality. The presence of elevated liver enzymes may precede the development of MetS, with alterations of the liver being observed that are directly related to metabolic problems. The study aims to provide the best evidence on the association between liver enzymes (ALT, AST, GGT) and MetS by determining the effect size of these biomarkers.

METHODS

A systematic review and meta-analysis of studies indexed in PubMed and Scopus databases were performed. Study quality was assessed using the STROBE tool. The Grade Pro tool was used to evaluate the evidence, and the quantitative synthesis was performed using RevMan (Cochrane Collaboration).

RESULTS

Seventeen articles comparing liver enzyme concentrations between 76,686 with MetS (MetS+) and 201,855 without MetS (MetS-) subjects were included. The concentration of ALT, AST and GGT in the MetS + subjects was significantly higher than in the control group 7.13 IU/L (CI95% 5.73-8.54; p < 0.00001; I2 = 96%), 2.68 IU/L (CI95% 1.82-3.54; p < 0.00001; I2 = 96%) and 11.20 IU/L (CI95% 7.11-15.29; p < 0.00001; I2 = 96%), respectively.

CONCLUSIONS

The evaluation of the relationship of liver enzymes in the pathophysiological process of MetS could lead to new insights into early diagnosis.

An individual patient data meta-analysis to determine cut-offs for and confounders of NAFLD-fibrosis staging with magnetic resonance elastography

BACKGROUND & AIMS

We conducted an individual patient data meta-analysis to establish stiffness cut-off values for magnetic resonance elastography (MRE) in staging liver fibrosis and to assess potential confounding factors.

METHODS

A systematic review of the literature identified studies reporting MRE data in patients with NAFLD. Data were obtained from the corresponding authors. The pooled diagnostic cut-off value for the various fibrosis stages was determined in a two-stage meta-analysis. Multilevel modelling methods were used to analyse potential confounding factors influencing the diagnostic accuracy of MRE in staging liver fibrosis.

RESULTS

Eight independent cohorts comprising 798 patients were included in the meta-analysis. The area under the receiver operating characteristic curve (AUROC) for MRE in detecting significant fibrosis was 0.92 (sensitivity, 79%; specificity, 89%). For advanced fibrosis, the AUROC was 0.92 (sensitivity, 87%; specificity, 88%). For cirrhosis, the AUROC was 0.94 (sensitivity, 88%, specificity, 89%). Cut-offs were defined to explore concordance between MRE and histopathology: ≥F2, 3.14 kPa (pretest probability, 39.4%); ≥F3, 3.53 kPa (pretest probability, 24.1%); and F4, 4.45 kPa (pretest probability, 8.7%). In generalized linear mixed model analysis, histological steatohepatitis with higher inflammatory activity (odds ratio 2.448, 95% CI 1.180-5.079, p <0.05) and high gamma-glutamyl transferase (GGT) concentration (>120U/L) (odds ratio 3.388, 95% CI 1.577-7.278, p <0.01] were significantly associated with elevated liver stiffness, and thus affecting accuracy in staging early fibrosis (F0-F1). Steatosis, as measured by magnetic resonance imaging proton density fat fraction, and body mass index(BMI) were not confounders.

CONCLUSIONS

MRE has excellent diagnostic performance for significant, advanced fibrosis and cirrhosis in patients with NAFLD. Elevated inflammatory activity and GGT level may lead to overestimation of early liver fibrosis, but anthropometric measures such as BMI or the degree of steatosis do not.

IMPACT AND IMPLICATIONS

This individual patient data meta-analysis of eight international cohorts, including 798 patients, demonstrated that MRE achieves excellent diagnostic accuracy for significant, advanced fibrosis and cirrhosis in patients with NAFLD. Cut-off values (significant fibrosis, 3.14 kPa; advanced fibrosis, 3.53 kPa; and cirrhosis, 4.45 kPa) were established. Elevated inflammatory activity and gamma-glutamyltransferase level may affect the diagnostic accuracy of MRE, leading to overestimation of liver fibrosis in early stages. We observed no impact of diabetes, obesity, or any other metabolic disorder on the diagnostic accuracy of MRE.

Effects of curcumin/turmeric supplementation on liver function in adults: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

INTRODUCTION

Liver conditions are major burdens upon health systems around the world. Turmeric /curcumin is believed to possess therapeutic features in ameliorating various metabolic disorders. In this systematic review and meta-analysis of the randomized controlled trials (RCTs), we examined the effect of turmeric/curcumin supplementation on some liver function tests (LFTs).

METHODS

We comprehensively searched online databases (i.e. PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar) from inception up to October 2022. Final outcomes included aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyl transferase (GGT). Weighted mean differences (WMDs) were reported. In case of between-study heterogeneity, subgroup analysis was conducted. Non-linear dose-response analysis was carried out to detect the potential effect of dosage and duration. The registration code is CRD42022374871.

RESULTS

Thirty-one RCTs were included in the meta-analysis. Turmeric/curcumin supplementation significantly reduced blood levels of ALT (WMD = -4.09 U/L; 95 % CI = -6.49, -1.70) and AST (WMD = -3.81 U/L; 95 % CI = -5.71, -1.91), but not GGT (WMD: -12.78 U/L; 95 % CI: -28.20, 2.64). These improvements, though statistically significant, do not ensure clinical effectiveness.

CONCLUSION

It seems that turmeric/curcumin supplementation might be effective in improving AST and ALT levels. However, further clinical trials are needed to examine its effect on GGT. Quality of the evidence across the studies was low for AST and ALT and very low for GGT. Therefore, more studies with high quality are needed to assess this intervention on hepatic health.

Gamma-glutamyltransferase predicts macrovesicular liver graft steatosis - an analysis of discarded liver allografts in Finland

OBJECTIVE

Liver-transplantation activity is limited by the shortage of grafts. Donor-liver macrovesicular steatosis predisposes to ischemia-reperfusion injury and is associated with reduced graft survival. The increasing prevalence of fatty-liver disease underlines the importance of identifying macrovesicular steatosis in potential donor livers. We analyzed liver grafts discarded for transplantation, and particularly the role of gamma-glutamyltransferase (GGT) in predicting graft steatosis.

METHODS

One-hundred sixty rejected cadaveric-donor liver grafts were studied. Donor selection was based on clinical data, and macroscopic graft inspection. Discarded grafts were biopsied at procurement of non-liver organs.

RESULTS

The most common reasons for discarding the graft were abnormal liver tests, ultrasound-verified steatosis and history of harmful alcohol use. GGT correlated moderately with macrovesicular steatosis (r = 0.52, p < 0.001), but poorly with microvesicular steatosis (r = 0.36, p < 0.001). Increased correlation between GGT and macrovesicular steatosis was observed among alcohol abusers (r = 0.67, p < 0.001). Area under the curve (AUC) of GGT for predicting >30% macrovesicular steatosis was 0.79 (95% CI 0.71-0.88), and for >60% steatosis, 0.79 (95% CI 0.68-0.90). The optimal GGT-cut off for detecting >30% and >60% macrovesicular steatosis were, respectively, 66 U/L (sensitivity 76% and specificity 68%) and 142 U/L (sensitivity 66% and specificity 83%). Among alcohol users, a GGT value >90 U/L showed 100% sensitivity for >60% macrovesicular steatosis. AUC for GGT in predicting fibrosis Stages 2-4 was 0.82 (95% CI 0.71-0.92, p < 0.001, optimal cut off 68, sensitivity 92%, specificity 61%).

CONCLUSIONS

Abnormal liver values, steatosis and harmful alcohol use were the main reasons for discarding liver-graft offers in Finland. GGT proved useful in predicting moderate and severe liver graft macrovesicular steatosis.

Significance of Fib4 index as an indicator of alcoholic hepatotoxicity in health examinations among Japanese male workers: a cross-sectional and retrospectively longitudinal study

BACKGROUND

Fib4 index (Fib4) is clinically used as a noninvasive marker of liver fibrosis. In this study, we aimed to preliminarily investigate whether Fib4 can be used to detect individuals who need assessment for alcoholic liver disease (ALD) in the general population by clarifying the detailed association of Fib4 with alcohol consumption and gamma-glutamyl transferase (GGT) among male workers.

METHODS

We analyzed data sets on the comprehensive medical examinations of male workers as cross-sectional and retrospectively longitudinal studies. We enrolled 10 782 males (mean age: 52.2 ± 10.2 years) in FY2019 and 7845 males (mean follow-up: 12.6 ± 6.7 years) who could be consecutively followed up for 20 years from FY2000 to FY2019. Data were evaluated using logistic regression and COX proportional analysis.

RESULTS

In the cross-sectional setting, the rate of Fib4 ≥ 2.67 in heavy drinkers (≥ 40 g of ethanol/day) was increased dose dependently in those over 65 years old, and that of body mass index ≥ 30 kg/m² was increased in those over 60 years old, but not in those with fatty liver. The odds ratio (OR) (95% confidence interval [CI]) for heavy drinking was 4.30 (95% CI = 1.90-9.72), and GGT ≥ 200 IU/L was considerably high (OR = 29.05 [95% CI = 17.03-49.56]). In the longitudinal setting, heavy drinkers and those with GGT ≥ 200 IU/L at 10 years after the baseline showed an increased risk for Fib4 ≥ 2.67 (hazard ratio = 2.17 [95% CI = 1.58-2.98] and 7.65 [95% CI 5.26-11.12], respectively).

CONCLUSIONS

The development of Fib4 ≥ 2.67 after 10 years was associated with heavy alcohol drinking and GGT level ≥ 200 IU/L. Therefore, Fib4 combined with GGT could indicate high risk of ALD. However, clinical examinations and course observations are essentially needed.

The potential effects of HECTD4 variants on fasting glucose and triglyceride levels in relation to prevalence of type 2 diabetes based on alcohol intake

Excessive alcohol intake is an important cause of major public health problem in East Asian countries. Growing evidence suggests that genetic factors are associated with alcohol consumption and the risk for alcohol-associated disease, and these factors contribute to the risk of developing chronic diseases, including diabetes. This study aims to investigate the association of type 2 diabetes with genetic polymorphisms within HECTD4 based on alcohol exposure. We performed a genome-wide association study involving the cohorts of the KoGES-HEXA study (n = 50,028) and Ansan and Ansung study (n = 7,980), both of which are prospective cohort studies in Korea. The top three single-nucleotide polymorphisms (SNPs) of the HECTD4 gene, specifically rs77768175, rs2074356 and rs11066280, were found to be significantly associated with alcohol consumption. We found that individuals carrying the variant allele in these SNPs had lower fasting blood glucose, triglyceride, and GGT levels than those with the wild-type allele. Multiple logistic regression showed that statistically significant associations of HECTD4 gene polymorphisms with an increased risk of type 2 diabetes were found in drinkers. Namely, these SNPs were associated with decreased odds of diabetes in the presence of alcohol consumption. As a result of examining the effect of alcohol on the expression of the HECTD4 gene, ethanol increased the expression of HECTD4 in cells, but the level was decreased by NAC treatment. Similar results were obtained from liver samples of mice treated with alcohol. Moreover, a loss of HECTD4 resulted in reduced levels of CYP2E1 and lipogenic gene expression in ethanol-treated cells, while the level of ALDH2 expression increased, indicating a reduction in ethanol-induced hepatotoxicity.

Obese Vegetarians and Omnivores Show Different Metabolic Changes: Analysis of 1340 Individuals

Our study evaluated the association between the increase in body mass index (BMI) in men and women (menstruating and non-menstruating) (n = 1340) with different dietary groups (omnivores, semi-vegetarians, lacto-ovo-vegetarian, and vegans) and the measurement of the biochemical markers high-sensitive C-reactive protein (hs-CRP), ferritin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), glycated hemoglobin (HbA1C), and insulin resistance index (HOMA-IR). Increasing BMI values in all groups and dietary profiles were related to a significant increase in hs-CRP (p < 0.0001), ALT (p = 0.02), ferritin (p = 0.009), and HbA1C (p < 0.0001), with no difference between dietary groups (p < 0.05). The increase in BMI increases the levels of HOMA-IR (p < 0.0001) and GGT (p < 0.05), with higher values found in men when compared to women (p < 0.0001 for HOMA- IR and p = 0.0048 for GGT). The association between ALT and BMI was different between dietary groups, as it showed a decrease in vegan women who do not menstruate compared to other dietary groups (p = 0.0099). When including only obese individuals (BMI ≥ 30 kg/m2, n = 153) in the analysis, we observed lower concentrations of GGT and ferritin in vegetarians than in omnivores, regardless of gender and menstrual blood loss (p = 0.0395). Our data showed that for both vegetarians and omnivores, the higher the BMI, the worse the metabolic parameters. However, regarding obesity, vegetarians showed better antioxidant status (lower GGT elevation) and lower inflammatory status (lower ferritin elevation), which may provide them with potential protection in the development of morbidities associated with overweight.

Changes of Tumor Markers in Patients with Breast Cancer during Postoperative Adjuvant Chemotherapy

Objective

Serum tumor marker (STM) elevation can detect metastasis earlier than imaging diagnosis and, although not recommended by guidelines, is still widely used in clinical practice for postoperative follow-up of breast cancer patients. The purpose of this study was to investigate the change rules of CEA and CA153 in patients with HER2-negative breast cancer during postoperative adjuvant chemotherapy and their influencing factors.

Materials and Methods

The medical records of patients with HER2-negative early breast cancer who visited Xuanwu Hospital from September 2018 to June 2021 were retrospectively analyzed. Demographic characteristics and baseline data of CEA and CA153 at initial diagnosis were collected. Data of CEA, CA153, biochemistry (including ALT, AST, rGT, triglycerides, cholesterol, and blood glucose) and blood routine (including white blood cells, neutrophils, monocytes, lymphocytes, and platelets) were also collected before chemotherapy, at the end of chemotherapy and more than 3 months after the end of chemotherapy. LY/MONO, NEUT/LY, PLT/LY, and systemic immune inflammation index (SII) were calculated and statistically analyzed using SPSSAU software.

Results

A total of 90 patients were enrolled, all of whom were female, with a mean age of 55.11 ± 10.60 y. The value of CEA at initial diagnosis was 2.10 ± 1.11 ng/mL, and high expression was mostly correlated with past history of chronic diseases and tumor lymph node metastasis; the value of CA153 was 11.80 ± 6.60 U/mL, and high expression was correlated with high SII at initial diagnosis. Surgery did not affect the values of serum CEA and CA153. At the end of chemotherapy, CEA and CA153 were 2.68 ± 1.34 ng/mL and 18.51 ± 8.50 U/mL, respectively, which were significantly increased compared with those before chemotherapy, and were linearly correlated with the values before chemotherapy. They decreased (CEA 2.45 ± 1.19 ng/mL, CA153 10.87 ± 5.96 U/mL) again three months after the end of chemotherapy, manifested as "spiking" phenomenon, which was associated with lymph node metastasis at diagnosis, body metabolic disorders, and chronic inflammatory status.

Conclusion

CEA and CA153 were increased presenting as "spiking" phenomena in patients with early HER2-negative breast cancer during postoperative adjuvant chemotherapy, and the peak of increase was linearly correlated with the indicators before chemotherapy. Clinical attention should be paid to this change to avoid excessive diagnosis and treatment leading to medical resource consumption.

Association of the serum transaminase with mortality among the US elderly population

BACKGROUND AND AIM

Considering the inconsistent findings of research into the associations between serum levels of liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], and gamma-glutamyltransferase [GGT]) and mortality among elderly people, we aimed to investigate the associations of ALT, AST, GGT, and De-Ritis ratio (DRR, defined as AST/ALT) and all-cause or cause-specific mortality among the US elderly people using National Health and Nutrition Examination Surveys data.

METHODS

We included 6415 elderly participants (≥ 65 years). Exclusion criteria included positive test for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus infection at baseline. Multivariable-adjusted Cox regression models calculating hazard ratios (HR) and 95% confidence intervals were developed for each of the liver enzyme measures.

RESULTS

All-cause cumulative mortality was 33.8%, of which 23.8% were cardiovascular disease (CVD) deaths, 15.6% were cancer deaths, and 60.6% were other cause deaths. Adjusted Cox models found increased all-cause mortality risk for low ALT (HR: 1.70), low AST (HR: 1.13), high GGT (HR: 1.25), and high DRR (HR: 1.68). Low ALT and high DRR predicted CVD mortality. Low ALT (HR: 1.91), low AST (HR: 1.16), high GGT (HR: 1.40), and high DRR (HR: 1.76) predicted other cause mortality.

CONCLUSIONS

Low ALT and high DRR were associated with increased CVD and cancer mortality. All serum liver enzyme measures were associated with all-cause mortality and other cause mortality in the US elderly population. Further studies may validate these findings in other elderly populations.

Noninvasive Risk Stratification for Nonalcoholic Fatty Liver Disease Among Living Liver Donor Candidates: A Proposed Algorithm

To reduce waitlist mortality, living donor liver transplantation (LDLT) has increased over the past decade in the United States, but not at a rate sufficient to completely mitigate organ shortage. As a result, there are ongoing efforts to expand the living liver donor pool. Simultaneously, the prevalence of nonalcoholic fatty liver disease (NAFLD) in the general population has increased, which has significant implications on the pool of potential living liver donors. As such, a clinical assessment algorithm that exhaustively evaluates for NAFLD and fibrosis is critical to the safe expansion of LDLT. An ideal algorithm would employ safe and noninvasive methods, relying on liver biopsy only when necessary. While exclusion of NAFLD and fibrosis by noninvasive means is widely studied within the general population, there are no well-accepted guidelines for evaluation of living donors using these modalities. Here we review the current literature regarding noninvasive NALFD and fibrosis evaluation and propose a potential algorithm to apply these modalities for the selection of living liver donors.

Prevalence and associations of metabolic syndrome in patients with alcohol use disorder

Excessive alcohol consumption has been associated with different components of the metabolic syndrome (MetS) such as arterial hypertension, dyslipidemia, type 2 diabetes or obesity. We aimed to analyze the prevalence and associations of MetS in patients with Alcohol Use Disorder (AUD). Cross-sectional study in heavy drinkers admitted for the treatment of AUD between 2013 and 2017. Medical comorbidity, anthropometric data, alcohol use and biological parameters were obtained. MetS was established according to the harmonized definition. A total of 728 patients (22% women) were included; median age was 47 years (IQR: 40–53.5), median alcohol consumption was 160 g/day (IQR: 115–240) and prevalence of MetS was 13.9%. The multivariate analysis showed a significant dose–response effect of estimated glomerular filtration (eGFR) and MetS: relative to patients with eGFR > 90 mL/min, those with eGFR (60–90 mL/min) and those with eGFR < 60 mL/min were 1.93 times (95% CI 1.18–3.15) and 5.61 times (95% CI 1.66–19.0) more likely to have MetS, respectively. MetS was significantly associated with hyperuricemia (OR 2.28, 95% CI 1.36–3.82) and elevated serum GGT (OR 3.67, 95% CI 1.80–7.46). Furthermore, for every increase of 1 year in age, the probability of MetS increased significantly (OR 1.03, 95% CI 1.01–1.05). MetS in heavy drinkers is independently associated with reduced kidney function and metabolic risk factors including hyperuricemia and elevated serum GGT.

Use of GP73 in the diagnosis of non-alcoholic steatohepatitis and the staging of hepatic fibrosis

OBJECTIVE

To evaluate the utility of Golgi protein 73 (GP73) in the diagnosis of non-alcoholic steatohepatitis (NASH) and hepatic fibrosis (HF) staging.

METHODS

Ninety-one patients with non-alcoholic fatty liver disease (NAFLD) were allocated to NAFL (n = 46) and NASH (n = 45) groups according to their NAFLD activity score (NAS), and there were 30 healthy controls. Serum GP73 was measured by ELISA, GP73 protein expression was evaluated using immunohistochemistry, and FibroScan was used to determine liver hardness.

RESULTS

The serum GP73 concentrations of the NAFL and NASH groups were significantly higher than those of controls. GP73 expression in the liver of the patients gradually progressed from absent or low to moderate or high. Serum GP73 positively correlated with liver expression, and the serum and liver GP73 of the patients positively correlated with FibroScan value and HF stage. There was a strong positive correlation of the combination of alanine aminotransferase, gamma glutamyl transferase and GP73 with NASH. The combination of serum GP73 and FibroScan value was found to predict NASH (NAS > 4) and advanced HF (stage ≥2) in patients with NAFLD using receiver operating characteristic analysis.

CONCLUSION

Serum GP73 may be useful in the diagnosis of NASH and the staging of HF.

Serum gamma-glutamyl transferase, a marker of alcohol intake, is associated with telomere length and cardiometabolic risk in young adulthood

Studies based on self-reported alcohol consumption and telomere length show inconsistent results. Therefore, we studied the association between gamma-glutamyl transferase (GGT), a widely used biomarker of alcohol intake, and telomere length. The possible health relevance in young adulthood was explored by investigating cardiometabolic risk factors. Mixed modelling was performed to examine GGT and alcohol consumption in association with telomere length in buccal cells of 211 adults between 18 and 30 years old of the East Flanders Prospective Twin Survey. In addition, we investigated the association between GGT and cardiometabolic risk factors; waist circumference, systolic blood pressure, fasting glucose, HDL cholesterol, and triglycerides. Although we did not observe an association between self-reported alcohol consumption and telomere length, our results show that a doubling in serum GGT is associated with 7.80% (95% CI − 13.9 to − 1.2%; p = 0.02) shorter buccal telomeres, independently from sex, chronological age, educational level, zygosity and chorionicity, waist-to-hip ratio and smoking. The association between GGT was significant for all five cardiometabolic risk factors, while adjusting for age. We show that GGT, a widely used biomarker of alcohol consumption, is associated with telomere length and with risk factors of cardiometabolic syndrome, despite the young age of this study population.

Gamma-glutamyl transpeptidase elevation is associated with metabolic syndrome, hepatic steatosis, and fibrosis in patients with nonalcoholic fatty liver disease: A community-based cross-sectional study

This study aimed to analyze the association between elevated gamma-glutamyl transpeptidase (GGT) and metabolic syndrome (MetS), hepatic steatosis, and fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). From August 2013 to August 2018, a community-based study was conducted in the northeastern part of Taiwan. Patients who underwent abdominal ultrasonography (US) and had no history of alcoholic liver disease were included. According to a US examination showing fatty liver degree, 1566 patients with NAFLD were divided into four groups: normal GGT, isolated GGT elevation, isolated alanine aminotransferase (ALT) elevation, and both GGT and ALT elevation groups. Further 1147 participants with normal serum ALT, GGT, and the abdominal US were included as the control group. GGT levels were associated with high sensitivity C-reactive protein, lower adiponectin, diabetes mellitus, and chronic kidney disease. A stepwise increase in odds ratio (OR) for MetS was found in the normal GGT group (OR = 1.71), isolated GGT elevation group (OR = 3.06), isolated ALT elevation (OR = 4.00), and both GGT + ALT elevation group (OR = 4.17) than the control group. Linear regression analysis revealed a positive association between GGT/ALT value and hepatic steatosis degree, GGT value, and degree of hepatic fibrosis. Hence, GGT elevation is associated with MetS, hepatic steatosis, and fibrosis in patients with NAFLD.

Index of Cardiac Age Index and Cardiometabolic Biomarkers in Adults with Metabolic Syndrome

Background: The presence of metabolic syndrome (MetS) seems to alter or accelerate the aging process of tissues or organs including the heart. We aim to investigate whether MetS are associated with an index of cardiac age calculated by parameters derived from 128-slice cardiac multidetector computed tomography (MDCT) and cardiometabolic biomarkers in adults. Materials and Methods: In this cross-sectional study, the data were collected from 135 subjects who underwent a comprehensive health checkup, including cardiac MDCT in adults (age ≥18 years). Cardiometabolic biomarkers and an index of cardiac age were measured. Results: Sixty-one (45.2%) had MetS and 44 subjects (32.6%) presented with moderate or severe coronary artery stenosis (CAS) on cardiac MDCT. MetS had positive correlations with several anthropometric variables, metabolic variables [triglyceride, gamma-glutamyl transpeptidase (GGT), homeostatic model assessment of insulin resistance (HOMA-IR)], and systolic blood pressure, cardiac parameters, an index of cardiac age and CAS, whereas had a negative correlation with high-density lipoprotein cholesterol. The diagnostic accuracy for MetS had similar area under the curve among the four variables (index of cardiac age, CAS, HOMA-IR, GGT). On age-adjusted multivariate analysis, only high index of cardiac age (≥55.0 years), and high HOMA-IR (≥1.22) were significantly and independently associated with MetS [odds ratio (OR) 2.48, 95% confidence interval (CI) 1.19-5.18, P = 0.016 and OR 3.41, 95% CI 1.65-7.06, P = 0.001, respectively]. Conclusion: Adults with MetS had higher index of cardiac age and higher HOMA-IR, compared with adults without MetS.

Development and Validation of a Machine Learning Prognostic Model for Hepatocellular Carcinoma Recurrence After Surgical Resection

Surgical resection remains primary curative treatment for patients with hepatocellular carcinoma (HCC) while over 50% of patients experience recurrence, which calls for individualized recurrence prediction and early surveillance. This study aimed to develop a machine learning prognostic model to identify high-risk patients after surgical resection and to review importance of variables in different time intervals. The patients in this study were from two centers including Eastern Hepatobiliary Surgery Hospital (EHSH) and Mengchao Hepatobiliary Hospital (MHH). The best-performed model was determined, validated, and applied to each time interval (0-1 year, 1-2 years, 2-3 years, and 3-5 years). Importance scores were used to illustrate feature importance in different time intervals. In addition, a risk heat map was constructed which visually depicted the risk of recurrence in different years. A total of 7,919 patients from two centers were included, of which 3,359 and 230 patients experienced recurrence, metastasis or died during the follow-up time in the EHSH and MHH datasets, respectively. The XGBoost model achieved the best discrimination with a c-index of 0.713 in internal validation cohort. Kaplan-Meier curves succeed to stratify external validation cohort into different risk groups (p < 0.05 in all comparisons). Tumor characteristics contribute more to HCC relapse in 0 to 1 year while HBV infection and smoking affect patients' outcome largely in 3 to 5 years. Based on machine learning prediction model, the peak of recurrence can be predicted for individual HCC patients. Therefore, clinicians can apply it to personalize the management of postoperative survival.

Evaluation of the Relationship between Insulin Resistance and HBV DNA Level in Patients with HBeAg-negative Chronic HBV Infection (Natural Course Phase 3)

Background and aims

Chronic hepatitis B (CHB) infection is an important cause of morbidity and mortality worldwide with an increased risk of liver failure, cirrhosis, and hepatocellular carcinoma. Hepatitis B virus (HBV) DNA level, the marker of viral load in the host, is a parameter affected by host factors. In this study, we investigated the relationship between HBV DNA level and insulin resistance as a host factor.

Methods

In this study, 146 patients diagnosed with “HBeAg-negative chronic HBV infection” (natural course phase 3, inactive carrier) according to the European Association for the Study of the Liver (EASL) 2017 guidelines were retrospectively analyzed and demographic, anthropometric, histopathological, radiological and laboratory data of the patients were recorded. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) levels of the patients were calculated, and according to the value, the patients were divided into two groups as insulin resistant and non-insulin resistant. All parameters, including HBV DNA, were evaluated and compared between the two groups.

Results

77 patients (52.7%) were insulin resistant with a HOMA-IR value of 2.5 or more. The remaining 69 patients (47.3%) whose HOMA-IR value less than 2.5 were non-insulin resistant. The median HBV DNA was 410 IU in the insulin-resistant group and 350 IU in the other group, and there was no statistical significance between the two groups (p: 0.537). HBV DNA level was only positive correlated with HBsAg level and negatively correlated with anti-Hbs level and age (p < 0.005). Compared to the non-insulin resistant group, body mass index (BMI), presence of hepatosteatosis on ultrasonography (USG), fasting blood sugar, fasting insulin, total protein, gamma glutamyl transferase (GGT), triglyceride (TG), very-low-density lipoprotein (VLDL), uric acid level, triglyceride/high-density lipoprotein (HDL) ratio were significantly higher and HDL levels were significantly lower in the insulin-resistant group (p < 0.005). GGT levels and TG/HDL ratio were found to be higher in patients with hepatosteatosis on ultrasonography than in patients without hepatosteatosis (p < 0.005). TG/HDL ratio was found to be an independent factor in predicting insulin resistance and every 1 unit increase of this ratio increases the risk of developing insulin resistance 2.1 times.

Conclusion

In this study, no significant relationship was found between insulin resistance and HBV DNA levels in chronic inactive HBV carriers. In addition, insulin resistance was observed more frequently in these patients compared to the general population, and insulin resistance was found to be associated with high BMI, hepatosteatosis rate, VLDL, TG, GGT, total protein, uric acid, TG/HDL ratio, and low HDL. TG/HDL ratio was found to be successful in predicting insulin resistance.

How to cite this article

Senoymak MC, Ozkan H. Evaluation of the Relationship between Insulin Resistance and HBV DNA Level in Patients with HBeAg-negative Chronic HBV Infection (Natural Course Phase 3). Euroasian J Hepatogastroenterol 2020;10(2):85–91.

Disease Activity Score in 28 Joints Using GGT Permits a Dual Evaluation of Joint Activity and Cardiovascular Risk

OBJECTIVE

To identify the factors potentially associated with serum gamma-glutamyltransferase (GGT) elevation in patients with rheumatoid arthritis (RA).

METHODS

This is a cross-sectional monocentric study including RA patients over a 12-month period. Data on liver function, RA disease activity, and hepatotoxic and cardiovascular (CV) risk factors were systematically collected. To provide a simple tool to evaluate both joint disease activity and CV risk factors, we constructed the Disease Activity Score in 28 joints (DAS28)-GGT composite index by replacing erythrocyte sedimentation rate (ESR) with GGT.

RESULTS

Among the 129 included patients, 32 (25%) had isolated GGT increase. GGT correlated with age, C-reactive protein (CRP) levels, and body weight and were significantly increased in patients with alcohol intake, type 2 diabetes mellitus, hypertension, dyslipidemia, and metabolic syndrome. GGT levels also gradually increased with the number of CV risk factors and correlated with the Framingham CV risk score. The composite index DAS28-GGT remained a reliable marker of RA disease activity and accurately detected patients with CV risk factors. Conversely to the DAS28 and the DAS28-CRP, the DAS28-GGT steadily increased according to the number of CV risk factors and had an increased diagnostic value compared to the DAS28 and DAS28-CRP for the presence of at least 2 CV risk factors and a Framingham CV risk score greater than 10%.

CONCLUSION

GGT may be considered as a marker of systemic inflammation and CV risk in patients with RA. Based on these findings, we herein propose an original index, the DAS28-GGT, which is able to evaluate both joint disease activity and CV risk. This index will deserve further validation in prospective cohorts.

Association of hyperuricemia and gamma glutamyl transferase as a marker of metabolic risk in alcohol use disorder

Excessive alcohol consumption leads to overproduction of urates and renal function plays a critical role in serum uric acid levels. We aimed to assess associations of hyperuricemia in patients with alcohol use disorder (AUD) and comparable Glomerular Filtration Rate (GFR). A total of 686 patients undergoing treatment for AUD between 2013 and 2017 were eligible (77% men); age at admission was 47 years [interquartile range (IQR), 40-53 years], age of onset of alcohol consumption was 16 years [IQR, 16-18 years] and the amount of alcohol consumed was 160 g/day [IQR, 120-240 g/day]. Body Mass Index was 24.7 kg/m² [IQR, 21.9-28.4 kg/m²], eGFR was 105 mL/min/1.73 m² [IQR, 95.7-113.0 mL], 9.7% had metabolic syndrome and 23% had advanced liver fibrosis (FIB-4 > 3.25). Prevalence of hyperuricemia was 12.5%. The eGFR-adjusted multivariate analysis showed that relative to patients with GGT ≤ 50, those with GGT between 51 and 300 U/L and those with GGT > 300 U/L were 4.31 (95% CI 1.62-11.46) and 10.3 (95% CI 3.50-29.90) times more likely to have hyperuricemia, respectively. Our data shows that hyperuricemia in the context of AUD is strongly associated with serum GGT levels and suggest an increased cardio-metabolic risk in this population.

Frequently abnormal serum gamma-glutamyl transferase activity is associated with future development of fatty liver: a retrospective cohort study

BACKGROUND

Nonalcoholic fatty liver disease is characterized by excessive hepatic fat accumulation. Some individuals frequently present elevated gamma-glutamyl transferase (GGT) levels without fatty liver ultrasound images and other abnormal liver enzymes levels. However, whether these individuals are at an elevated risk for developing fatty liver is unclear. We compared fatty liver change rates and risk factors between individuals with frequently elevated GGT levels and those with normal levels.

METHODS

We designed a retrospective cohort study on the basis of complete medical checkup records. One group of individuals had presented normal serum GGT levels during the observation period (Normal-GGT group, n = 2713). Another group had had abnormal elevated serum GGT levels frequently (Abnormal-GGT group, n = 264). We determined the fatty liver change incident rates before and after propensity score matching. We explored confounding factors affecting fatty changes in each group using univariate and multivariate Cox models.

RESULTS

The change incidence rates were 5.80/1000 and 10.02/1000 person-years in the Normal-GGT and Abnormal-GGT groups, respectively. After propensity score matching, the incidence rates were 3.08/1000 and 10.18/1000 person-years in the Normal-GGT and Abnormal-GGT groups, respectively (p = 0.026). The factors associated with fatty liver changes in the Normal-GGT group included body mass index (BMI), hemoglobin, alanine aminotransferase (ALT), albumin, triglyceride (TG), fasting blood sugar, and high-density lipoprotein levels. Those in the Abnormal-GGT group were platelet counts and TG. In our multivariable analysis, BMI, ALT, albumin, and TG levels were independent predictors of fatty changes in the Normal-GGT group, and high TG level was the only independent predictor in the Abnormal-GGT group.

CONCLUSIONS

The incidence rate of fatty liver change in the Abnormal-GGT group was higher than that in the Normal-GGT group. Consecutive elevated GGT levels increase the risk for fatty liver, and high TG levels in those individuals further independently increase the risk.

Calcium and Phosphate Levels are Among Other Factors Associated with Metabolic Syndrome in Patients with Normal Weight

BACKGROUND AND PURPOSE

We aimed to assess the association between calcium and phosphorous and metabolic syndrome (MetS) in normal-weight individuals.

PATIENTS AND METHODS

The study sample comprised 460 normal-weight (body mass index <25kg/m²) adults aged 18-35 years. The diagnosis of MetS was based on the presence of at least two of the following: 1) systolic blood pressure (SBP) ≥130 mmHg or diastolic blood pressure (DBP) ≥85 mmHg, 2) triglycerides (TG) >150 mg/dl, 3) high-density lipoprotein cholesterol (HDL-C) <1 mmol/in men and <1.2 mmol/l in women, 4) total cholesterol (TC) >5.2 mmol/l, and 5) fasting glucose (FBG) >5.55 mmol/l.

RESULTS

Patients with MetS were more often male and slightly older and they had a higher body mass index (BMI) and waist circumference. By definition, patients with MetS had higher levels of BP, GLC, glycated hemoglobin A1c, TC, low-density lipoprotein cholesterol (LDL-C), TG, and apolipoprotein B but significantly lower concentrations of HDL-C and apolipoprotein A. Moreover, subjects with MetS had higher activity of the liver enzymes alanine aminotransferase, alkaline phosphatase and gamma-glutamyl transpeptidase (GGTP). Higher concentrations of uric acid, creatinine and albumin (ALB) were also observed in subjects with MetS. The factors associated with MetS in the multivariate analysis were higher GGTP activity (OR per 5 unit increase - 1.23 (1.11-1.37); p<0.0001), a higher BMI (OR - 1.28 (1.1-1.52); p=0.003), a higher concentration of calcium (OR per 0.1 mmol/l increase - 1.79 (1.21-2.7); p=0.004), higher ALB levels (OR per 5 g/l increase - 1.76 (1.11-2.95), p=0.02); higher phosphorous levels (OR per 0.1 mmol/l increase - 0.82 (0.67-0.99); p=0.04), and a good household situation (odds ratio (OR) - 0.58 95% confidence interval (CI) (0.31-1.07); p=0.08).

CONCLUSION

Calcium and phosphorus levels are significantly associated with MetS in normal-weight individuals.

The 7-Year Change in the Prevalence of Insulin Resistance, Inflammatory Biomarkers, and Their Determinants in an Urban South African Population

BACKGROUND

Insulin resistance (IR) and subclinical inflammation are involved in pathological pathways leading to the development of biological cardiovascular risk factors and subsequent cardiovascular events. Therefore, monitoring these processes can provide advanced information on the trajectory of cardiovascular risk profile of a population and inform prevention and control strategies. We investigated changes in IR and subclinical inflammation in a population from Cape Town, South Africa, between 2008/09 and 2014/16.

METHODS

In a total of 2503 (n = 797, 2008/09) and (n = 1706, 2014/16) participants, IR was calculated using five indices, i.e., insulin fasting, HOMA-IR, QUICKI, McAuley, and Matsuda while subclinical inflammation was measured using usCRP and gamma GT. Linear and logistic regression analyses and interaction tests were conducted.

RESULTS

The mean age of participants was 53.2 (2008/09) and 48.2 (2014/16), respectively. In females, IR prevalence significantly decreased between 2008/09 and 2014/2016 by all indices (p ≤ 0.021), while subclinical inflammation prevalence increased from 54.7% (2008/09) to 57.1% (2014/16) based on usCRP and 29.6% to 33.4% based on gamma GT. In a multivariate analysis adjusted for the year of study, age, and gender, prominent factors associated with increased IR or subclinical inflammation were obesity levels measured using waist circumference, glycated haemoglobin, and fasting insulin levels.

CONCLUSIONS

Over the 7-year period, subclinical inflammation increased and this was associated with IR and the metabolic syndrome components, both of which are strong predictors of CVDs. The decrease in IR over the year period reflects in part the much younger age in the second survey.

Association between Serum Gamma-Glutamyltransferase and Prevalence of Metabolic Syndrome Using Data from the Korean Genome and Epidemiology Study

BACKGROUND

The aim of this study was to determine whether there is a positive correlation between gamma-glutamyltransferase (GGT) levels and the prevalence of metabolic syndrome and whether GGT can be used as an easily checkable metabolic index using data from the large-scale Korean Genome and Epidemiology Study (KoGES).

METHODS

We obtained data of 211,725 participants of the KoGES. The collected data included age, sex, height, weight, waist circumference, and various biochemical characteristics, including serum GGT levels. The data of study participants who ingested more than 40 g/day of alcohol and who were diagnosed with metabolic syndrome at baseline was excluded. We analyzed the prevalence of metabolic syndrome according to GGT quartiles in both genders.

RESULTS

The GGT level was significantly higher in subjects with metabolic syndrome compared to normal subjects (37.92±48.20 mg/dL vs. 25.62±33.56 mg/dL). The prevalence of metabolic syndrome showed a stepwise increase with GGT quartiles in both male and female subjects. Compared to the lowest GGT quartile, the odds ratio was 1.534 (95% confidence interval [CI], 1.432 to 1.643), 1.939 (95% CI, 1.811 to 2.076), and 2.754 (95% CI, 2.572 to 2.948) in men and 1.155 (95% CI, 1.094 to 1.218), 1.528 (95% CI, 1.451 to 1.609), and 2.022 (95% CI, 1.921 to 2.218) in women with increasing GGT quartile. The cutoff value of GGT predicting risk of metabolic syndrome was 27 IU/L in men and 17 IU/L in women.

CONCLUSION

We suggested that GGT could be an easily checkable marker for the prediction of metabolic syndrome.

Multi-ancestry sleep-by-SNP interaction analysis in 126,926 individuals reveals lipid loci stratified by sleep duration

Both short and long sleep are associated with an adverse lipid profile, likely through different biological pathways. To elucidate the biology of sleep-associated adverse lipid profile, we conduct multi-ancestry genome-wide sleep-SNP interaction analyses on three lipid traits (HDL-c, LDL-c and triglycerides). In the total study sample (discovery + replication) of 126,926 individuals from 5 different ancestry groups, when considering either long or short total sleep time interactions in joint analyses, we identify 49 previously unreported lipid loci, and 10 additional previously unreported lipid loci in a restricted sample of European-ancestry cohorts. In addition, we identify new gene-sleep interactions for known lipid loci such as LPL and PCSK9. The previously unreported lipid loci have a modest explained variance in lipid levels: most notable, gene-short-sleep interactions explain 4.25% of the variance in triglyceride level. Collectively, these findings contribute to our understanding of the biological mechanisms involved in sleep-associated adverse lipid profiles.

EVALUATION OF SERUM γ-GLUTAMYL TRANSFERASE AND ITS ASSOCIATION WITH HIGH SENSITIVITY C-REACTIVE PROTEIN AND INSULIN LEVELS IN THE PATIENTS WITH METABOLIC SYNDROME

Background. Metabolic syndrome (MS), a collection of cardiovascular risk factors, is a major worldwide public health problem. The gathered data prove that serum gamma-glutamyl transferase (γGT) activity is a true marker of atherosclerotic cardiovascular disease (CVD) and is of a prognostic importance as well as the high-sensitivity C-reactive protein (hs-CRP). Objectives. In the study, we sought to evaluate serum γGT activity, hs-CRP and insulin resistance in patients with MS. Methods. The study involved 50 persons with metabolic syndrome and 50 healthy age and sex matched controls. Fasting serum samples of all participants were investigated for γGT, hs-CRP, insulin, blood glucose, lipid profile and liver function tests. Anthropometric measurements and BMI were also calculated Results. In that case 50% showed significantly high γGT compared to the controls, 30% proved increased hs-CRP levels above >0.5 mmol/L, whereas 94% of the controls were within the reference range. 74% of cases revealed the presence of insulin resistance while 32% of the controls showed insulin resistance. High γGT levels were also observed in that case with deranged lipids levels and high BMI. Conclusions. The study suggests that the patients with MS have a higher serum γGT activity. This study also proves that hs-CRP and HOMA-IR, which are independent risk factors of CVD, are also associated with MS. The correlation between γGT and the components of MS are also found significant compared to hs-CRP. Thus, γGT can be considered as an inexpensive and authentic predictor of MS, which can be a manifestation of CVD in near future.

Elevated liver enzymes and cardiovascular mortality: a systematic review and dose-response meta-analysis of more than one million participants

Gamma glutamyl transferase (GGT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) are commonly used liver function markers. We performed a dose-response meta-analysis to investigate the association between liver enzymes and cardiovascular disease (CVD) mortality in prospective cohort studies. We conducted a systematic search up to April 2018 in Medline/PubMed, Scopus, Cochrane, and Embase databases. Combined hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using a random-effects model as described by DerSimonian and Laird. Dose-response analysis was also carried out. Twenty-three studies with 1 067 922 participants reported association between GGT and CVD mortality and were included in our analysis. Pooled results showed a significant association between GGT and risk of CVD mortality (HR: 1.62; 95% CI: 1.47-1.78, P=0.001, P-heterogeneity=0.001) and it was HR: 0.87; 95% CI: 0.73-1.07; P=0.221, P-heterogeneity=0.028, for ALT. There was a direct association between baseline levels of ALP and AST/ALT ratio with CVD mortality (HR: 1.45; 95% CI: 1.11-1.89; P=0.005, P-heterogeneity=0.026, and HR: 2.20; 95% CI: 1.60-3.04; P=0.001, P-heterogeneity=0.540, respectively). Pooled results did not show any significant association between AST and the risk of CVD mortality (HR: 1.20; 95% CI: 0.83-1.73; P=0.313, P-heterogeneity=0.024). Moreover, there was a significant nonlinear association between GGT and ALP levels and the risk of CVD mortality (P=0.008 and 0.016, respectively). Our dose-response meta-analysis revealed a direct relationship between GGT and ALP levels and the risk of CVD mortality. High levels of GGT, ALP and AST/ALT were associated with an increased CVD mortality rate.

Gamma-Glutamyltransferase (GGT) as a biomarker of cognitive decline at the end of life: contrasting age and time to death trajectories

ABSTRACTBackground:A recently published study suggests that Gamma-Glutamyltransferase (GGT) in midlife is related to an increased risk of dementia. In the present longitudinal study, we explore the effects of serum GGT on cognitive decline and dementia also in more advanced ages.

METHODS

We analyzed GGT in a sample of 452 individuals, aged 80 years and older at baseline, with the purpose to explore subsequent effects on cognitive performance. We specifically modeled GGT to cognitive change, time to death, and dementia.

RESULTS

Our main finding is that a higher level of GGT is associated with cognitive decline prior to death and vascular dementia in late life. These findings were evident across cognitive domains.

CONCLUSIONS

This is the first longitudinal study to report on significant associations in late life between GGT, cognitive performance and dementia. Further research is needed to examine the underlying mechanisms of GGT as a marker of age-related cognitive decline.

Genetically elevated gamma-glutamyltransferase and Alzheimer's disease

Observational epidemiological evidence supports a linear and independent association between serum gamma-glutamyltransferase (GGT) concentrations and the risk of Alzheimer's disease (AD). However, the causality of this association has not been previously investigated. We sought to assess the causal nature of this association using a Mendelian randomization (MR) approach. Using inverse-variance weighted MR analysis, we assessed the association between GGT and AD using summary statistics for single nucleotide polymorphism (SNP)-AD associations obtained from the International Genomics of Alzheimer's Project of 17,008 individuals with AD and 37,154 controls. We used 26 SNPs significantly associated with GGT in a previous genome-wide association study on liver enzymes as instruments. Sensitivity analyses to account for potential genetic pleiotropy included MR-Egger and weighted median MR. The odds ratio of AD was 1.09 (95% confidence interval, 0.98 to 1.22; p = 0.10) per one standard deviation genetically elevated GGT based on all 26 SNPs. The results were similar in both MR-Egger and weighted median MR methods. Overall, our findings cannot confirm a strong causal effect of GGT on AD risk. Further MR investigations using individual-level data are warranted to confirm or rule out causality.

Relationship between serum gamma-glutamyltransferase activity and cardiometabolic risk factors in metabolic syndrome

Objectives

The objective of this study was to examine the associations of serum gamma-glutamyltransferase (GGT) levels with the metabolic syndrome (MetS) and its components in Saudi adults.

Methods

The study comprised 400 participants (70 men and 330 women), aged between 40 and 88 years, randomly selected from the medicine clinics at the King Abdulaziz University Hospital in Jeddah, Saudi Arabia, in a cross-sectional study design. A standardized questionnaire was used to determine demographics variables, general health, lifestyle habits, and medical history. Anthropometric and biochemical variables measurements were taken for all study participants. MetS was defined according to the American Heart Association/National Heart, Lung, and Blood Institute report, by the presence of abdominal obesity.

Results

Higher means for triglycerides and insulin resistance indices (P < 0.0001) was found among those in the second, third, and fourth GGT quartiles as compared with their counterparts in the first quartile. McAuley index (β = -0.239, P < 0.0001, 95% confidence interval: -4.1--1.5) was shown to be a major determinant of circulating GGT in a multivariate analysis.

Conclusion

Elevated serum GGT could be a cardiometabolic risk factor either as a mediator of low-grade systemic inflammation and as a mediator of oxidative stress through mediation of extracellular glutathione transport into cells of organ systems.

A comparison of gamma-glutamyl transferase and alkaline phosphatase as prognostic markers in patients with coronary heart disease

BACKGROUND AND AIMS

Whether gamma-glutamyl transferase (GGT) or alkaline phosphatase (ALP) is a better prognostic marker in patients with coronary heart disease (CHD) remains unknown. The aim of this study was to compare the prognostic value of GGT and ALP in patients with CHD.

METHODS AND RESULTS

This study included 3768 patients with CHD. The main study outcome was 3-year all-cause mortality. The median values of GGT and ALP were 36.2 U/L and 69.3 U/L. Patients were divided into subgroups according to GGT or ALP activity > or ≤median. Overall, there were 304 deaths: 195 deaths occurred in patients with GGT >median (n = 1882) and 109 deaths occurred in patients with GGT ≤median (n = 1886); Kaplan-Meier [KM] estimates of all-cause mortality were 11.9% and 6.4% (unadjusted hazard ratio [HR] = 1.85, 95% confidence interval [CI], 1.46 to 2.34]; P < 0.001). According to ALP activity, 186 deaths occurred in patients with ALP >median (n = 1883) and 118 deaths occurred in patients with ALP ≤median (n = 1885); KM estimates of all-cause mortality were 11.4% and 7.1% (unadjusted HR = 1.64 [1.30-2.06]; P < 0.001). After adjustment, GGT (adjusted HR = 1.32 [1.11-1.58]; P = 0.002) but not ALP (adjusted HR = 1.20 [1.00-1.43]; P = 0.051, with both HR calculated per 1 unit increment in logarithmic GGT or ALP scale) remained significantly associated with the risk for mortality. The C statistic of the mortality model with GGT was greater than the C statistic of the model with ALP (0.831 [0.802-0.859] vs. 0.826 [0.793-0.855]; P < 0.001).

CONCLUSIONS

In patients with CHD, GGT was a stronger correlate of all-cause mortality than ALP.

Amino acid profile and metabolic syndrome in a male Mediterranean population: A cross-sectional study

BACKGROUND AND AIMS

The metabolic syndrome (MetS) refers to a cluster of clinically relevant factors that increases the risk of cardiovascular diseases and all-cause mortality. Circulating levels of several amino acids and metabolites related to one-carbon metabolism have been associated with cardiometabolic risk factors and MetS. We aimed to identify the amino acid profile that is significantly associated with MetS among an all male Mediterranean population.

METHODS AND RESULTS

One hundred middle-aged men (54.6 ± 8.9 years) participated in a cross-sectional study carried out during 2011-2012. The International Diabetes Federation (IDF) criteria were used to define MetS. Fasting plasma levels of 20 common amino acids and 15 metabolites related to amino acid and one-carbon metabolism were measured using gas chromatography (GC-MS/MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Principal components analysis was applied. Fifty-six participants fulfilled the IDF criteria for defining MetS. Five factors were extracted from the 35 measured metabolites. The branched-chain amino acids/aromatic amino acids (BCAA/AAA) related pattern and the glutamine/glycine/serine/asparagine (Gln/Gly/Ser/Asn) related pattern were significantly associated with MetS (odds ratio, 95% confidence interval; 6.41, 2.43-16.91, and 0.47, 0.23-0.96, respectively) after adjustment for age, current smoking status, physical activity level and medical treatment for hypertension, dyslipidaemia, type 2 diabetes mellitus. Further adjustment for liver function markers (i.e. glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and γ-glutamyltransferase), and plasma adiponectin levels did not significantly affect the associations.

CONCLUSION

The BCAA/AAA pattern was positively associated, while the Gln/Gly/Ser/Asn pattern was inversely associated with established cardiometabolic risk factors and MetS. Plasma adiponectin levels or markers of liver function did not significantly affect these associations.

Gamma-glutamyltransferase-friend or foe within?

Gamma-glutamyltransferase (GGT) is a liver enzyme, which is located on the plasma membranes of most cells and organ tissues, but more commonly in hepatocytes, and is routinely used in clinical practice to help indicate liver injury and as a marker of excessive alcohol consumption. Among the liver enzymes, important advances have especially been made in understanding the physiological functions of GGT. The primary role of GGT is the extracellular catabolism of glutathione, the major thiol antioxidant in mammalian cells, which plays a relevant role in protecting cells against oxidants produced during normal metabolism; GGT, therefore, plays an important role in cellular defence. Beyond its physiological functions, circulating serum GGT has been linked to a remarkable array of chronic conditions and diseases, which include nonalcoholic fatty liver disease, vascular and nonvascular diseases and mortality outcomes. This review summarizes the available epidemiological and genetic evidence for the associations between GGT and these adverse outcomes, the postulated biologic mechanisms underlying these associations, outlines areas of outstanding uncertainty and the implications for clinical practice.

Gamma-glutamyltransferase and risk of hypertension: a systematic review and dose-response meta-analysis of prospective evidence

The objective of this review was to obtain a reliable estimate of the magnitude of the prospective association between gamma-glutamyltransferase (GGT) and risk of hypertension, and to characterize the nature of the dose-response relationship. We conducted a systematic review and dose-response meta-analysis of published prospective studies. Relevant studies were identified in a literature search of MEDLINE, EMBASE, and Web of Science databases up to May 2015. Study-specific relative risks (RRs) were meta-analyzed using random effects models. We examined a potential nonlinear relationship using restricted cubic splines. Of the 612 titles reviewed, we included 14 cohort studies with data on 44 582 participants and 5 270 hypertension cases. In a comparison of extreme thirds of baseline levels of GGT, RR for hypertension in pooled analysis of all 14 studies was 1.32 (95% confidence interval: 1.23-1.43). There was heterogeneity among the studies (P < 0.001), which was to a large part explained by average age of participants at baseline, average duration of follow-up, and the degree of confounder adjustment. In a pooled dose-response analysis of 10 studies with relevant data, there was evidence of a linear association between GGT and hypertension risk (P for nonlinearity = 0.37). The pooled RR of hypertension per 5 U/l increment in GGT levels was 1.08 (95% confidence interval: 1.04-1.13). Baseline circulating GGT level is associated with an increased risk of hypertension in the general population, consistent with a linear dose-response relationship. Further investigation of any potential relevance of GGT in hypertension prevention is warranted.

Nonalcoholic fatty liver disease is associated with an almost twofold increased risk of incident type 2 diabetes and metabolic syndrome. Evidence from a systematic review and meta-analysis

BACKGROUND AND AIM

The magnitude of the risk of incident type 2 diabetes (T2D) and metabolic syndrome (MetS) among patients with nonalcoholic fatty liver disease (NAFLD) is poorly known. We gauged the risk of developing T2D and MetS in patients with NAFLD diagnosed by either serum liver enzymes (aminotransferases or gamma-glutamyltransferase [GGT]) or ultrasonography.

METHODS

Pertinent prospective studies were identified through extensive electronic database research, and studies fulfilling enrolment criteria were included in the meta-analysis.

RESULTS

Overall, in a pooled population of 117020 patients (from 20 studies), who were followed-up for a median period of 5 years (range: 3-14.7 years), NAFLD was associated with an increased risk of incident T2D with a pooled relative risk of 1.97 (95% confidence interval [CI], 1.80-2.15) for alanine aminotransferase, 1.58 (95% CI, 1.43-1.74) for aspartate aminotransferase, 1.86 (95% CI, 1.71-2.03) for GGT (last vs first quartile or quintile), and 1.86 (95% CI, 1.76-1.95) for ultrasonography, respectively. Overall, in a pooled population of 81411 patients (from eight studies) who were followed-up for a median period of 4.5 years (range: 3-11 years), NAFLD was associated with an increased risk of incident MetS with a pooled relative risk of 1.80 (95% CI, 1.72-1.89) for alanine aminotransferase (last vs first quartile or quintile), 1.98 (95% CI, 1.89-2.07) for GGT, and 3.22 (95% CI, 3.05-3.41) for ultrasonography, respectively.

CONCLUSIONS

Nonalcoholic fatty liver disease, as diagnosed by either liver enzymes or ultrasonography, significantly increases the risk of incident T2D and MetS over a median 5-year follow-up.

Effect of the three-dimensional organization of liver cells on the biogenesis of the γ-glutamyltransferase fraction pattern

Context Four gamma-glutamyltransferase (GGT) fractions with different molecular weights (big-, medium-, small- and free-GGT) are detectable in human plasma. Objective Verify if liver cells can release all four GGT fractions and if the spatial cell organization influences their release. Methods Hepatoma (HepG2) and melanoma (Me665/2/60) cells were cultured as monolayers or spheroids. GGT released in culture media was analysed by gel-filtration chromatography. Results HepG2 and Me665/2/60 monolayers released the b-GGT fraction, while significative levels of s-GGT and f-GGT were detectable only in media of HepG2-spheroids. Bile acids alone or in combination with papain promoted the conversion of b-GGT in s-GGT or f-GGT, respectively. Conclusions GGT is usually released as b-GGT, while s-GGT and f-GGT are likely to be produced in the liver extracellular environment by the combined action of bile acids and proteases.

Physical Activity Is Prospectively Associated With Adolescent Nonalcoholic Fatty Liver Disease

OBJECTIVES

The aim of the present study was to assess whether objectively measured physical activity at mean ages 12 and 14 years are prospectively associated with ultrasound scan liver fat and stiffness (alanine aminotransferase, aspartate aminotransferase [AST], and γ-glutamyl transferase [GGT]) assessed at mean age 17.8 years.

METHODS

Participants were from the Avon Longitudinal Study of Parents and Children. Total physical activity (counts per minute) and minutes of moderate to vigorous physical activity (MVPA) were measured using ActiGraph accelerometers at mean ages 12 and 14 years.

RESULTS

Greater total physical activity and MVPA at ages 12 and 14 years were associated with lower odds of liver fat and lower GGT levels at mean age 17.8 years, such as per 15-minute increase in daily MVPA at age 12 years, the confounder adjusted odds ratio of liver fat was 0.47 (95% confidence interval [CI] 0.27-0.84). Associations attenuated after additional adjustment for fat mass as a potential confounder (eg, per 15-minute increase in daily MVPA at age 12 years, the odds ratio of liver fat attenuated to 0.65 [95% CI 0.35-1.21]) or a potential mediator (eg, per 15-minute increase in daily MVPA at age 12 years the odds ratio of liver fat attenuated to 0.59 [95% CI 0.32-1.09]). Results did not further attenuate after additional adjustment for insulin resistance. There was some evidence that greater total physical activity and MVPA at age 12 years were associated with the higher AST levels.

CONCLUSIONS

Adolescents who were more active in childhood have lower odds of fatty liver and lower GGT levels. These findings are likely to be, at least in part, explained by adiposity.

Serum Gamma-Glutamyltransferase Levels are Associated With Concomitant Cardiovascular Risk Factors in Korean Hypertensive Patients: A Nationwide Population-Based Study

Previous studies suggested that serum gamma-glutamyltransferase (GGT) levels were associated with the prevalence of cardiovascular disease (CVD) risk factors including hypertension, diabetes mellitus (DM), and metabolic syndrome (MetS) in the general population. We aimed to investigate the relationship between serum GGT levels and CVD risk factors in Korean hypertensive patients. This cross-sectional study was based on data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2011 to 2012. The analysis included 1541 hypertensive participants. Study participants were divided into groups according to tertiles of serum GGT with cutoff points of 20 and 35 U/L. Serum GGT levels were positively associated with the components of MetS (P value < 0.05, except for systolic blood pressure and high-density lipoprotein cholesterol). After adjusting for possible confounders, serum GGT levels were associated with an increased risk of MetS, high waist circumference, high triglyceride level, fasting plasma glucose, DM, and the urinary albumin-to-creatinine ratio (P = 0.001). In hypertensive patients, serum GGT levels are positively associated with major cardiovascular risk factors such as MetS, DM, and urinary albumin excretion.

A Risk Score with Additional Four Independent Factors to Predict the Incidence and Recovery from Metabolic Syndrome: Development and Validation in Large Japanese Cohorts

Background

Although many risk factors for Metabolic syndrome (MetS) have been reported, there is no clinical score that predicts its incidence. The purposes of this study were to create and validate a risk score for predicting both incidence and recovery from MetS in a large cohort.

Methods

Subjects without MetS at enrollment (n = 13,634) were randomly divided into 2 groups and followed to record incidence of MetS. We also examined recovery from it in rest 2,743 individuals with prevalent MetS.

Results

During median follow-up of 3.0 years, 878 subjects in the derivation and 757 in validation cohorts developed MetS. Multiple logistic regression analysis identified 12 independent variables from the derivation cohort and initial score for subsequent MetS was created, which showed good discrimination both in the derivation (c-statistics 0.82) and validation cohorts (0.83). The predictability of the initial score for recovery from MetS was tested in the 2,743 MetS population (906 subjects recovered from MetS), where nine variables (including age, sex, γ-glutamyl transpeptidase, uric acid and five MetS diagnostic criteria constituents.) remained significant. Then, the final score was created using the nine variables. This score significantly predicted both the recovery from MetS (c-statistics 0.70, p<0.001, 78% sensitivity and 54% specificity) and incident MetS (c-statistics 0.80) with an incremental discriminative ability over the model derived from five factors used in the diagnosis of MetS (continuous net reclassification improvement: 0.35, p < 0.001 and integrated discrimination improvement: 0.01, p<0.001).

Conclusions

We identified four additional independent risk factors associated with subsequent MetS, developed and validated a risk score to predict both incident and recovery from MetS.

Association of Serum Gamma-Glutamyl Transferase and Ferritin with the Metabolic Syndrome

Aim. To investigate the relationship among GGT, ferritin, and the risk of metabolic syndrome. Methods. A total of 1024 eligible individuals of the Chinese Yi ethnic group were enrolled in this cross-sectional study. The presence of metabolic syndrome was determined using the revised NCEP-ATP III and CDS criteria. Odds ratios for the metabolic syndrome and its components for different groups based on the levels of GGT and ferritin were calculated using multiple logistic regressions. Results. Serum GGT and ferritin concentrations were significantly higher in subjects with metabolic syndrome compared to those without metabolic syndrome in both genders (p < 0.05). Serum GGT was positively correlated with ferritin (p < 0.05). The risk of the metabolic syndrome was significantly higher in female subjects who had elevated GGT and ferritin levels (p < 0.05). Furthermore, the increased risk of having each of the metabolic syndrome components (overweight or obesity, hypertriglyceridemia, hypertension, hyperglycemia, and insulin resistance) was also observed in those subjects after adjustment for possible confounders (p < 0.05). Conclusions. These data indicate that GGT and ferritin synergistically correlate with the risk of the metabolic syndrome, suggesting that they could potentially be used as predictive biomarkers for the metabolic syndrome.