Relationship between gamma-glutamyltransferase and metabolic syndrome in a Korean population

2,5-Dihydroxyterephthalic Acid: A Matrix for Improved Detection and Imaging of Amino Acids

Amino acids (AAs), which are low-molecular-weight (low-MW) metabolites, serve as essential building blocks not only for protein synthesis but also for maintaining the nitrogen balance in living systems. In situ detection and imaging of AAs are crucial for understanding more complex biological processes. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is a label-free mass spectrometric imaging technique that enables the simultaneous detection and imaging of the spatial distribution and relative abundance of different endogenous/exogenous compounds in biological samples. The excellent efficiency of MALDI-MSI is attributed to the choice of the MALDI matrix. However, to the best of our knowledge, no matrix has been specifically developed for AAs. Herein, we report a MALDI matrix, 2,5-dihydroxyterephthalic acid (DHT), which can improve the detection and imaging of AAs in biological samples by MALDI-MS. Our results indicated that DHT exhibited strong ultraviolet-visible (UV-vis) absorption, uniform matrix deposition, and high vacuum stability. Moreover, the matrix-related ion signals produced from DHT were reduced by 50 and 71.8% at m/z < 500 compared to the commonly used matrices of 2,5-dihydroxybenzoic acid (DHB) and α-cyano-4-hydroxycinnamic acid (CHCA), respectively, in their respective organic solvents. In terms of quantitative performance, arginine, glutamic acid, glutamine, and proline can be detected with limits of detection of 6, 4, 6, and 4 ng/mL, respectively, using the DHT as the matrix. Using DHT as the matrix, all 20 protein AAs were successfully detected in human serum by MALDI-MS, whereas only 7 and 10 AAs were detected when DHB and CHCA matrices were used, respectively. Furthermore, 20 protein AAs and taurine were successfully detected and imaged in a section of edible Crassostrea gigas (oyster) tissue for the first time. Our study demonstrates that using DHT as a matrix can improve the detection and imaging of AAs in biological samples by MALDI-MS.

Exploring the Potential Performance of Fibroscan for Predicting and Evaluating Metabolic Syndrome using a Feature Selected Strategy of Machine Learning

Metabolic syndrome (MetS) includes several conditions that can increase an individual's predisposition to high-risk cardiovascular events, morbidity, and mortality. Non-alcoholic fatty liver disease (NAFLD) is a predominant cause of cirrhosis, which is a global indicator of liver transplantation and is considered the hepatic manifestation of MetS. FibroScan^® provides an accurate and non-invasive method for assessing liver steatosis and fibrosis in patients with NAFLD, via a controlled attenuation parameter (CAP) and liver stiffness measurement (LSM or E) scores and has been widely used in current clinical practice. Several machine learning (ML) models with a recursive feature elimination (RFE) algorithm were applied to evaluate the importance of the CAP score. Analysis by ANOVA revealed that five symptoms at different CAP and E score levels were significant. All eight ML models had accuracy scores > 0.9, while treebags and random forest had the best kappa values (0.6439 and 0.6533, respectively). The CAP score was the most important variable in the seven ML models. Machine learning models with RFE demonstrated that using the CAP score to identify patients with MetS may be feasible. Thus, a combination of CAP scores and other significant biomarkers could be used for early detection in predicting MetS.

Can Gamma-glutamyl Transferase Predict Unhealthy Metabolic Phenotypes Among Healthcare Workers in Azar Cohort Study?

Background: Although various studies have assessed the correlation between gamma-glutamyl transferase (GGT) and cardiometabolic risk factors in obesity, no research has differentiated among metabolically-healthy obese (MHO) and metabolically unhealthy obese (MUHO), metabolically-healthy lean (MHL), and metabolically-unhealthy lean (MUHL). Objectives: Accordingly, this study evaluated the correlation between GGT and cardiometabolic phenotypes among healthcare workers. Methods: In this study, there were anthropometric measurements as well as the measurements of fasting blood sugar (FBS), GGT, cholesterol, triglyceride (TG), high lipoprotein density (HDL), and blood pressure in 1458 healthcare workers enrolled in the Azar Cohort Study. Metabolic syndrome (MetS) was defined according to the National Cholesterol Education Program Adult Treatment Panel III (ATP III). Accordingly, the participants were divided into four cardiometabolic phenotypes. Results: In this cross-sectional study, there was a significant difference in the prevalence of cardiometabolic phenotypes regarding the GGT tertiles (P ≤ 0.001). The highest prevalence of MHO was observed in the third GGT tertile. The mean waist circumference, TG, FBS, HDL, and systolic and diastolic blood pressure levels increased in the MHO, MUHO, and MHL groups in a dose dependent manner with an increase in the GGT tertiles (P < 0.05). In comparing the highest and lowest GGT tertile, the risk of MHO and MUHO increased by 2.84 (95%CI 2.01 - 4.01) and 9.12 (95%CI 5.54 - 15), respectively. However, the correlation between the GGT tertile and MUHL did not reveal a similar trend. The ROC curve shows the cutoff value of 18.5 U/L for GGT, which allowed us to distinguish between the MUHO and MHO individuals. Conclusions: The findings revealed that GGT can indicate the risk of MetS as such, it can be used to detect at-risk MHO individuals and administer proper interventions.

IS HOMEOSTASIS MODEL ASSESSMENT FOR INSULIN RESISTANCE >2.5 A DISTINGUISHED CRITERIA FOR METABOLIC DYSFUNCTION-ASSOCIATED FATTY LIVER DISEASE IDENTIFICATION?

BACKGROUND

Insulin resistance (IR), assessed by different criteria, is an important factor in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). More recently with the characterization of this metabolic dysfunction-associated fatty liver disease (MAFLD), one of the proposed criteria for this diagnosis has been the determination of the homeostasis model assessment-insulin resistance (HOMA-IR).

OBJECTIVE

The purpose of this study was to evaluate the relationship of HOMA-IR>2.5 with clinical, metabolic, biochemical and histological data obtained in non-diabetic patients diagnosed with NAFLD by liver biopsy.

METHODS

Cross-sectional, retrospective study was carried out with data from 174 adult individuals of both genders with non-diabetics NAFLD, without obvious signs of portal hypertension. The body mass index (BMI) was classified according to the World Health Organization (1998), and the metabolic syndrome by the criteria of NCEP-ATP-III. Biochemical tests were evaluated using an automated method and insulinemia through immunofluorometric assay. Histological findings were classified according to Kleiner et al. (2005).

RESULTS

The mean age of the studied population was 53.6±11.2 years, with 60.3% being female. The average BMI was 30.3 kg/m2 and 75.9% of the patients had increased waist circumference. Among evaluated metabolic parameters, there was a higher prevalence of metabolic syndrome (MS) in patients with HOMA-IR>2.5, with no statistical difference in relation to BMI between studied groups. Values of liver enzymes and serum ferritin were significantly higher in patients with this marker of IR, who had a higher prevalence of non-alcoholic steatohepatitis (NASH) and advanced liver fibrosis. In the multivariate analysis, the clinical diagnosis of MS, hyperferritinemia and the presence of NASH in the liver biopsy were the factors independently associated with the presence of altered HOMA-IR.

CONCLUSION

HOMA-IR values >2.5 identify patients with NAFLD with distinct clinical and metabolic characteristics and with a greater potential for disease progression, which validates this parameter in the identification of patients with MAFLD.

Associations Between GGT/HDL and MAFLD: A Cross-Sectional Study

PURPOSE

To explore the association between γ-glutamyl transpeptidase to high-density lipoprotein ratio (GGT/HDL), triglyceride glucose-body mass index (TYG-BMI), and metabolic associated fatty liver disease (MAFLD) in a Chinese population with type 2 diabetes (T2DM) by cross-sectional analysis. To investigate the role of GGT/HDL played in MAFLD by TYG-BMI.

PATIENTS AND METHODS

A total of 1434 adult patients hospitalized with T2DM at Hebei General Hospital (Shijiazhuang, China) were included in the study. Patients' demographic and clinical data were collected. Spearman correlation was used to test for an association between GGT/HDL or TYG-BMI and related risk factors of MAFLD among T2DM patients. Multiple logistic regression analyses were performed to investigate the association between GGT/HDL or TYG-BMI and MAFLD. Mediation analysis was used to explore whether TYG-BMI mediated the association between GGT/HDL and MAFLD.

RESULTS

A total of 1434 T2DM patients were enrolled, the MAFLD group showed a higher level of GGT/HDL compared to the non-MAFLD group. There was a progressive increase in the prevalence of MAFLD with increasing tertiles of GGT/HDL. After adjusting for confounding factors, multivariate logistic regression analysis revealed that high levels of GGT/HDL were independent risk factors for MAFLD in T2DM patients. BMI further grouped the patients: ≤ 23kg/m2,>23kg/m2. GGT/HDL was found to be an independent risk factor for MAFLD but only in T2DM patients with a BMI greater than 23 kg/m2. Mediation analysis indicated that GGT/HDL had a significant direct effect on MAFLD.

CONCLUSION

GGT/HDL was positively associated with MAFLD incidence in T2DM patients with a BMI greater than 23 Kg/m2, and TYG-BMI partly mediated the association.

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.

Potential impact of the joint association of total bilirubin and gamma-glutamyltransferase with metabolic syndrome

BACKGROUND

Metabolic syndrome is characterized by the clustering of different metabolic abnormalities. Total bilirubin and gamma-glutamyltransferase (GGT) levels have been reported to be associated with this condition. However, the extent to which the interaction between these parameters affects metabolic syndrome is unknown. Therefore, we examined the association of total bilirubin and GGT levels with metabolic syndrome, and investigated the combined effect of the two parameters.

METHODS

In this retrospective cohort study, we analyzed 8992 middle-aged Japanese subjects (4586 men, 4406 women; mean age, 44.8 ± 9.3 years) without metabolic syndrome from a cohort of employees undergoing annual health examinations. They were divided into four groups according to median total bilirubin and GGT levels: both-low, GGT-high, total bilirubin-high, and both-high. The incident of metabolic syndrome was evaluated during a follow-up of 2.8 ± 1.2 years.

RESULTS

The incident rate of metabolic syndrome during the follow-up was 4.6% in the both-low group, 12.1% in the GGT-high group, 2.7% in the total bilirubin-high group, and 10.6% in the both-high group. Total bilirubin and GGT have an interaction effect on the risk of incident metabolic syndrome (p = 0.0222). The both-low [hazard ratio (HR), 1.37; 95% confidence interval (CI) 1.002-1.89], GGT-high (HR, 1.88; 95% CI 1.42-2.52), and both-high (HR, 2.07; 95% CI 1.56-2.80) groups showed an increased adjusted HR for incident metabolic syndrome after adjusting for covariates compared with the total bilirubin-high group.

CONCLUSIONS

The simultaneous presence of high total bilirubin and low GGT levels may be associated with a lower incidence of metabolic syndrome.

Combined Effect of Initial and Longitudinal Increases in γ-Glutamyltransferase on Incident Metabolic Syndrome: ARIRANG Study

PURPOSE

Although γ-glutamyltransferase (GGT) is well known to be associated with metabolic syndrome (MS), prospective data on baseline and longitudinal changes in GGT levels and incident cases of MS are limited. We aimed to examine prospective associations between changes in GGT levels over time, as well as at baseline, and incident MS in Korean adults.

MATERIALS AND METHODS

A total of 2579 Korean adults free of MS were followed up for 2.6 years. Data were collected from 2005-2008 (baseline) and from 2008-2011 (follow-up). Serum GGT levels were determined by enzymatic methods.

RESULTS

During follow-up, 558 participants (21.6%) developed MS. A gradual increase in the incidence of MS was observed across GGT quartiles. After adjustment for confounding factors, the odds ratio and 95% confidence interval (CI) for new onset MS, comparing the highest to the lowest quartiles of baseline GGT, was 2.07 (95% CI: 1.52-2.80). The odds ratio for the highest GGT changes (>4 IU/L increase) in comparison to the lowest GGT changes (<-5 IU/L decrease) was 1.75 (95% CI: 1.32-2.33). Among participants with baseline GGT concentrations <the median, the odds ratio for incident MS, comparing participants with the highest GGT changes with the lowest GGT changes, was 1.52 (95% CI: 1.01-2.31). Among participants with baseline GGT concentration ≥the median, the corresponding odds ratio was 2.75 (95% CI: 1.84-4.10).

CONCLUSION

High initial GGT concentration and increases in GGT concentration over time should be considered independent predictors of and to have a combined effect on incident MS.

Elevated serum gamma-glutamyltransferase is associated with an increased risk of oesophageal carcinoma in a cohort of 8,388,256 Korean subjects

Gamma-glutamyltransferase (GGT) is a marker for hepatic injury and alcohol consumption. However, the association of GGT with the risk of oesophageal carcinoma (OC) has not been fully recognized to date. Therefore, this study aimed to determine the association between elevated GGT and OC, by also considering the body mass index (BMI) of the subjects. Clinical data from 8,388,256 Korean individuals, who were aged 40 years and over and who received healthcare check-ups arranged by the national insurance program in 2007 and 2008, were analysed. Newly diagnosed OC was identified using claims data during a median follow-up duration of 8.72 years. During the study period, 6,863 individuals (0.08%) developed OC. We found that there was an increased risk of OC in subjects with serum GGT values >18 IU/L. Furthermore, a BMI <18.5 kg/m² (underweight) was associated with increased OC risk, while a BMI ≥23.0 kg/m² was associated with a reduced OC risk. Individuals who were both underweight and in the highest GGT quartile (≥40 IU/L) had a far greater risk of OC compared to other individuals (hazard ratio: 3.65, 95% confidence interval: 3.10–4.30). In conclusion, increased serum GGT was associated with an increased risk of developing OC in the general Korean population, regardless of age, sex, smoker status, or alcohol consumption.

Association of adiposity, measures of metabolic dysregulation, and elevated alanine aminotransferase in subjects with normal body mass index

Background: Differences in body fat (BF) distribution in patients with normal body mass index (BMI) with elevated alanine aminotransferase (ALT) remains poorly described.

Objective: To determine the relationship between total BF, waist circumference (WC), insulin resistance (IR), and cardiometabolic risk profile in subjects with elevated ALT and normal BMI.

Methods: We analyzed cross-sectional data from 4,914 US participants in the third National Health and Nutrition Examination Survey database, who were ≥20 years of age, had normal BMI, and had body composition assessed by bioimpedance.

Results: Mean ± SD age was 41.4 ± 0.3 years, and 58% participants were women. BF was 20 ± 0.1% in men and 29.9 ± 0.1% in women. As total BF increased by tertiles, there was a tendency towards a higher prevalence of nonalcoholic fatty liver disease in men (6.1%, 6.5%, 9.5%, P = 0.13), but not in women (8.7%, 8.2%, 10.7%, P = 0.71). As WC increased by tertiles, there was a higher prevalence of elevated ALT in men (2.6%, 8.6%, 6.6%, P < 0.0001), but not in women. As ALT increased, men had significantly higher levels of nonhigh density lipoprotein cholesterol (HDL-C), increased apolipoprotein B, increased IR, and lower levels of C-reactive protein, whereas, women had higher levels of non-HDL-C and increased IR.

Conclusion: In subjects with normal BMI, increased WC is associated with a higher prevalence of elevated ALT in men, but not in women. Higher levels of ALT correlated with a poor cardiometabolic risk profile.

Gamma glutamyl transferase is an independent determinant for the association of insulin resistance with nonalcoholic fatty liver disease in Bangladeshi adults: Association of GGT and HOMA-IR with NAFLD

AIMS

Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver-related morbidity and is frequently associated with insulin resistance (HOMA-IR) syndrome. Recently serum gamma glutamyl transferase (GGT) has been considered as surrogate marker of NAFLD leading to oxidative stress and hepatocellular damage. In the present study we examined the association of serum GGT and HOMA-IR with NAFLD in Bangladeshi adult subjects.

MATERIALS AND METHODS

Under a cross-sectional analytical design a total of 110 subjects were recruited who came for their routine health check up in the BIHS Hospital, Darussalam, Dhaka, Bangladesh. After whole abdomen ultrasonography, 62 were diagnosed as non-NAFLD and 48 were NAFLD subjects. Serum glucose was measured by glucose-oxidase method, lipid profile and liver enzymes by enzymatic colorimetric method, glycosylated hemoglobin (HbA1c) was measured by high performance liquid chromatography (HPLC), serum insulin were measured by enzyme-linked immunosorbent assay. HOMA-IR was calculated by homeostasis model assessment (HOMA).

RESULTS

NAFLD subjects had significantly higher levels of GGT and HOMA-IR as compared to their non-NAFLD counterparts. Multiple linear regression analysis showed a significant positive association of HOMA-IR with GGT after adjusting the effects of waist circumference (WC) and HbA1c. In binary logistic regression analysis, HOMA-IR and GGT were found to be significant determinants of NAFLD after adjusting the effects of WC and HbA1c.

CONCLUSION

These results suggest that elevated levels of GGT and insulin resistance are more likely to develop NAFLD and thus support a role of these determinants in the pathogenesis of NAFLD in Bangladeshi adult subjects.

γ-Glutamyltransferase and cancer risk: The Korean cancer prevention study

Elevated serum γ-glutamyltransferase (GGT) is a marker of hepatic injury and is associated with risk of chronic disease. However, the value of GGT as a biomarker for cancer risk remains unclear. Therefore, we evaluated the association of serum GGT with cancer incidence among more than 1.6 million Koreans. We included 1,662,087 Koreans (1,108,121 men and 553,966 women aged 20-95 years) who received health insurance from the National Health Insurance Service and had a biennial medical evaluation between 1995 and 1998. Follow-up was through December 2012. Using Cox proportional hazards models, we adjusted for age, smoking status, alcohol consumption, exercise and body mass index after exclusion of early cases (cancer diagnosis or death within 5 years of starting follow-up) and estimated hazard ratios (HRs) of overall and organ-specific cancer incidence by GGT quintiles. During the 17-year follow-up, 129,087 new cancer cases occurred among the participants. Across levels of GGT, there was a positive gradient of HR and the highest quintile of GGT (≥ 60 IU/L) had the highest HR for all cancers in both men and women. By cancer site, the association was strongest for liver cancer, comparing the highest and lowest strata in men [HR, 6.67; 95% confidence interval (95%CI), 5.88-7.57] and in women (HR, 7.57; 95%CI, 6.41-8.94). Significant associations were also observed for cancers of the esophagus, larynx, stomach, colorectal, bile duct and lung in men and of the bile duct in women. Increased serum GGT level is independently associated with risk of cancer.

Serum hepatic enzyme activity and alcohol drinking status in relation to the prevalence of metabolic syndrome in the general Japanese population

Background

Studies on the combined associations of elevated serum hepatic enzyme activity and alcohol drinking with metabolic syndrome are rare. Our objectives were to evaluate the associations of elevated serum hepatic enzyme activity with the prevalence of metabolic syndrome in the general Japanese population and whether alcohol drinking had a modifying effect on these associations.

Methods

We conducted a cross-sectional study with 1,027 men and 1,152 women throughout Japan during 2002–2010. Biochemical factors including alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) were determined in overnight fasting blood, and a survey on lifestyle was conducted by questionnaire. Serum ALT and GGT levels were divided into tertiles in men and women, and their associations with the prevalence of metabolic syndrome were evaluated by logistic regressions.

Results

Elevated serum ALT and GGT, even within the reference range, were independently associated with increased metabolic syndrome prevalence and were associated with most of its components in both sexes, except for the association between GGT and low high-density lipoprotein (HDL) cholesterol in men. Stratified analyses by alcohol drinking status revealed that within the same tertile category of serum ALT and GGT, subjects classified as alcohol abstainers showed higher adjusted odds ratios for metabolic syndrome prevalence than those classified as regular alcohol drinkers in both sexes. The interaction effects of serum GGT with alcohol drinking status on metabolic syndrome prevalence were significant in both sexes.

Conclusions

These results suggest that elevated serum ALT and GGT, even within the reference range, are independently associated with increased metabolic syndrome prevalence, especially in alcohol abstainers, in Japanese men and women.

Synergistic effect of gamma glutamyltransferase and obesity on metabolic syndrome, independent of hepatic steatosis

PURPOSE

Both obesity and gamma glutamyltransferase (GGT) are individually considered to be closely associated with metabolic syndrome (MetS). Whether the 2 factors synergistically associate with MetS is not yet confirmed. The purpose of this study was to investigate whether obesity and GGT are interactively associated with MetS.

METHODS

A cross-sectional study of 7390 adults (age 32-62 years old) was conducted from 2009 to 2010.

RESULTS

Our results showed that greater serum GGT quartiles were positively associated with all MetS components and fatty liver (P < .001). The odds ratio of MetS increased significantly along with quartiles of GGT and obesity. In comparison with subjects with normal body mass index and first quartile GGT, the odds ratio of MetS in obese groups with 1st, 2nd, 3rd, and 4th quartile GGT were 6.8, 14.5, 20.3, and 45.2, respectively, and it remained tenable after adjustment for fatty liver. The synergy index of GGT and obesity on MetS is 2.2 (95% confidence interval, 1.9-2.6).

CONCLUSIONS

Serum GGT level in combination with obesity can be a simple but useful tool for risk stratification of developing MetS. Obese individuals with high-normal GGT levels require close monitoring for high risk of MetS.

Association between γ-glutamyltransferase, adiponectin and arterial stiffness

AIM

Serum γ-glutamyltransferase (GGT) is used as a marker of hepatic dysfunction. Recently, several studies reported that GGT is significantly associated with cardiovascular mortality and atherosclerosis. Adiponectin is known to play an important role in the development of atherosclerosis, but its physiologic role has yet to be fully determined. In this study, we investigated the relationships among serum GGT, adiponectin and arterial stiffness.

METHODS

Of 4236 subjects recruited from 17 different medical centers in Seoul, Korea, 2846 subjects were enrolled in our study. The parameters of metabolic syndrome (MetS) were assessed in these subjects, and their plasma adiponectin levels and pulse wave velocity (PWV) were measured along with anthropometric and biochemical profiles, including GGT.

RESULTS

The subjects were stratified into 3 groups according to GGT values. PWV values gradually increased and the adiponectin level decreased with GGT tertiles. Aortic PWV showed a significant correlation with age, SBP, FPG, but there was no correlation among aortic PWV, GGT and adiponectin. Peripheral PWV demonstrated a significant correlation with age, SBP, DBP, BMI, WC, FPG and GGT, but there was no correlation between peripheral PWV and adiponectin. In multiple logistic regression analysis after adjusting for risk factors, GGT was a significant contributor to increased peripheral PWV.

CONCLUSIONS

These findings indicate that serum GGT is independently associated with increased arterial stiffness, but there was no correlation between adiponectin and arterial stiffness in both males and females.

Serum gamma-glutamyltransferase concentration correlates with Framingham risk score in Koreans

Gamma-glutamyltransferase (GGT) is a novel coronary artery disease (CAD) risk factor, but its use as an independent factor for CAD risk prediction remains unclear in Asian population. This study examined the association between serum GGT concentration and Framingham risk score (FRS) in the Korean population. This cross-sectional study was performed on 30,710 Koreans. Besides FRS, body mass index, fasting blood glucose, liver enzymes, lipid profile, uric acid and high sensitive C-reactive protein data were used. The study subjects were grouped into quartiles according to the levels of GGT. Analyses relating GGT to FRS ≥ 20% utilized multiple confounders adjusted logistic regression. Positive correlations were established between log-transformed GGT concentration and FRS (r = 0.38; P < 0.001). Increasing the quartile of serum GGT concentration was significantly associated with linear increasing trends in FRS (P-trend < 0.001). Compared to the lowest baseline GGT category, age-gender adjusted odd ratios for FRS ≥ 20% were significantly increased from the lowest to highest GGT quartiles; these results remained significantly after adjustments for multiple confounders. Increased GGT concentration is associated with the increase in FRS. Serum GGT may be helpful to predict the future risk of CAD.

Association of serum alanine aminotransferase and γ-glutamyltransferase levels within the reference range with metabolic syndrome and nonalcoholic fatty liver disease

BACKGROUND/AIMS

Nonalcoholic fatty liver disease (NAFLD) has recently been found to be a novel component of metabolic syndrome (MS), which is one of the leading causes of chronic liver disease. The serum alanine aminotransferase (ALT) and ⟨-glutamyltransferase (GGT) levels are suggested to affect liver fat accumulation and insulin resistance. We assessed the associations of serum ALT and GGT concentrations within the reference ranges with MS and NAFLD.

METHODS

In total, 1,069 subjects enrolled at the health promotion center of Wonkwang University Hospital were divided into 4 groups according to serum ALT and GGT concentrations levels within the reference ranges. We performed biochemical tests, including liver function tests and lipid profiles, and diagnosed fatty liver by ultrasonography. Associations of ALT and GGT concentrationgrading within the reference range with fatty liver and/or MS were investigated.

RESULTS

The presence of MS, its components, and the number of metabolic abnormalities [except for high-density lipoprotein-cholesterol (HDL-C) and fasting blood glucose] increased with the ALT level, while the presence of MS, its components, and the number of metabolic abnormalities (except for HDL-C) increased with the GGT level. The odds ratios for fatty liver and MS increased with the ALT level (P⟨0.001 and P=0.049, respectively) and the GGT level (P=0.044 and P=0.039, respectively).

CONCLUSIONS

Serum ALT and GGT concentrations within the reference ranges correlated with the incidence of NAFLD and MS in a dose-dependent manner. There associations need to be confirmed in large, prospective studies.

Relationship between alcohol consumption and clinical manifestation of patients with fatty liver: a single-center study

BACKGROUND

Fatty liver is a common chronic liver disease worldwide. It is associated with an increasing morbidity in China in recent years. The aim of this study was to analyze the effect of drinking alcohol on the hemoglobin and biochemical values of patients with fatty liver.

METHODS

We investigated the clinical and laboratory data of 669 patients with fatty liver. Of the 669 patients, 166 consumed alcohol more than 60 g per week for at least 2 years, and 503 did not have a history of long-term alcohol consumption. We further analyzed the relationship between alcohol consumption and clinical characteristics of these patients.

RESULTS

The values of aspartate transaminase (AST), gamma-glutamyl transpeptidase (GGT), and hemoglobin in the long-term consumption group were significantly higher than those in the non long-term consumption group (P<0.05). In the patients without long-term alcohol consumption, the values of GGT and hemoglobin in patients with light alcohol consumption were significantly higher than those in non alcohol consumers (P<0.05).

CONCLUSION

Alcohol consumption is associated with significantly increased values of AST, GGT, and hemoglobin in patients with fatty liver, suggesting their potential roles in hepatic steatosis.

Association between alcohol intake amount and prevalence of metabolic syndrome in Korean rural male population

Moderate alcohol consumption is known to be associated with a reduced risk of cardiovascular disease and mortality. However, few studies reported that long-term alcohol drinking may increase the prevalence of central obesity, and cardiovascular disease. We examined the association between metabolic syndrome, nutritional factors and alcohol intake amount in Korean male rural population. We performed a cross-sectional analysis on data from Korean Rural Genomic Cohort (KRGC) study. We used multiple logistic regression analysis to estimate the adjusted odds ratio of metabolic syndrome according to alcohol intake amount categories (never, 0-16 g/day, 16-40 g/day, and >40 g/day). The age adjusted odds ratio for the prevalence of metabolic syndrome was significantly increased in the quartile with the highest alcohol consumption compared to the non-alcohol drinking group (1.33; C.I., 1.11-1.59). These results were similar in the high energy intake group, but not in the low energy intake group. Waist circumference, blood pressure, and serum triglyceride levels were significantly higher in the quartile with the highest alcohol consumption compared to the non-alcohol drinking group. These results suggest that large alcohol consumption is associated with metabolic syndrome and may be a modifiable risk factor of metabolic syndrome especially in subjects with high calorie intake.

Association between serum gamma-glutamyltransferase and acute ischemic nonembolic stroke in elderly subjects

BACKGROUND AND AIMS

Elevated serum gamma-glutamyltransferase (GGT) levels have been proposed as an independent predictor for cardiovascular morbidity and mortality. The aim of this study was to determine whether GGT levels are associated with acute ischemic/nonembolic stroke in a case-control study of elderly subjects.

METHODS

A total of 163 patients >70 years of age (88 men) admitted due to a first-ever acute ischemic/nonembolic stroke and 166 volunteers (87 men) without a history of cardiovascular disease were included. The association between GGT and stroke was determined by multivariate logistic regression modelling after adjusting for potential confounding factors.

RESULTS

GGT levels were higher in subjects with metabolic syndrome (MetS) and correlated with MetS individual components including insulin resistance. Stroke patients showed higher concentrations of GGT compared with controls. In univariate analysis, crude odds ratio (OR) for GGT was 1.06/1 IU/L increase (95% CI, 1.03-1.09; p<0.001). Compared to subjects with GGT levels in the lowest quartile, those within the highest quartile had a 4.7-times increase in the odds of experiencing an ischemic stroke (95% CI 2.39-9.11, p<0.001). This association remained significant after controlling for all potential confounders (adjusted OR, 2.90, 95% CI, 1.35-6.27; p=0.007). Analysis of interaction between MetS and GGT showed that subjects with MetS had a 1.08 higher odds/1 IU/L increase in GGT to experience an ischemic stroke [adjusted OR, 1.08 (95% CI, 1.04-1.12; p<0.001).

CONCLUSIONS

There are positive associations between serum GGT and first ischemic/nonembolic stroke in individuals >70 years of age independent of established risk factors for cardiovascular disease and concurrent metabolic abnormalities.

Lead-induced oxidative stress adversely affects health of the occupational workers

Lead is a persistent toxic metal and associated with impairment of various body functions in occupational workers. The main objective was to determine the lead-induced oxidative stress and adverse health effects by biochemical markers in industrial workers. One hundred and forty-eight males consisting of 87 lead-exposed industrial workers and 61 controls were included. Blood lead level (BLL) was determined on a 3010B ESA lead analyzer. Blood complete counts were done on a hematology analyzer. Biochemical markers including serum uric acid, urea, creatinine, phosphate, alanine aminotransferase (ALT), and gamma glutamyltransferase (GGT) were measured on a Selectra E auto analyzer. Serum malondialdehyde (MDA) was measured spectrophotometrically and C-reactive protein (CRP) on Immulite-1000. Results revealed that lead-exposed workers had significantly high BLLs, median (range), 29.1 (9.0-61.1) microg/dL compared with controls, 8.3 (1.0-21.7) microg/dL. Oxidative stress (MDA, GGT) and inflammatory markers (high-sensitivity CRP) were significantly increased (P < or = 0.05). Blood pressure was raised, whereas hemoglobin was decreased in exposed group (P < or = 0.002). Serum urea, uric acid, phosphate, and ALT were significantly raised in lead-exposed workers (P < or = 0.001). Serum albumin, total proteins, and glomerular filtration rate (GFR) were decreased. Blood lead showed a significant positive correlation with serum GGT (r = 0.63), MDA (r = 0.71), CRP (r = 0.75), urea (r = 0.34), creatinine (r = 0.51), and uric acid (r = 0.29) (P < or = 0.01). It is concluded that lead exposure increases oxidative stress that correlates with adverse changes in hematological, renal, and hepatic function in the occupational workers. Elevated blood lead has positive correlation with oxidative stress, inflammatory and biochemical markers that might be used to detect impairment in the body function in lead exposed workers.

Serum gamma-glutamyl transferase activity predicts future development of metabolic syndrome defined by 2 different criteria

BACKGROUND

Recent studies suggest the role of liver enzymes, such as serum gamma-glutamyl transferase (GGT) and alanine aminotransferase (ALT) as the predictor for future development of metabolic syndrome (MetS), diabetes and cardiovascular disease in epidemiologic studies. We hypothesized that serum concentrations of GGT and ALT are associated with the development of MetS, according to newly recommended criteria from International Diabetes Federation (IDF) and American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) definition in Koreans.

METHODS

A total of 15,250 males (mean 38 y) and 6280 females (mean 41 y) who visited the Health Promotion Center at Kangbuk Samsung Hospital for medical check-up in 2002, were followed-up after 4 y. We analyzed the development of MetS in their follow-up data in 2006.

RESULTS

When the subjects were divided into quartiles by the baseline GGT levels, the odds ratio for the MetS defined by both criteria across the quartile groups increased as the quartile groups increased in both gender groups. This association remained significant even after adjustment for confounding factors, such as, age, alcohol intake, smoking status, physical activity, ALT, fasting insulin and HOMA-IR. Serum ALT concentration also showed significantly positive correlation with development of MetS defined by the two criteria even after adjustment for age and GGT in both gender groups. In addition, risk for the individual MetS components increased as the baseline GGT concentrations increased, except low high-density lipoprotein cholesterol (HDL-C) in female group. In receiver operating characteristic (ROC) curves, the area under the curves (AUC) of GGT and ALT to predict future MetS by both criteria was larger than the AUCs of blood pressure, fasting glucose and HDL-C.

CONCLUSIONS

In this large prospective study in Koreans, high baseline GGT and ALT concentrations predicted future development of MetS defined by IDF and AHA/NHLBI criteria after 4 y of follow-up.

Alanine aminotransferase and gamma-glutamyl transferase are associated with the metabolic syndrome but not with angiographically determined coronary atherosclerosis

BACKGROUND

Recently, elevated liver enzymes have attracted great interest as potential novel markers of cardiovascular risk. Their association with angiographically determined coronary artery disease (CAD) is unknown.

METHODS

We enrolled 1000 consecutive patients undergoing coronary angiography for the evaluation of suspected or established stable CAD. The metabolic syndrome (MetS) was defined according to ATP-III criteria; significant CAD was diagnosed in the presence of coronary stenoses with lumen narrowing >or=50%.

RESULTS

Serum alanine aminotransferase (ALT), the ALT/aspartate aminotransferase (AST) ratio, and serum gamma-glutamyl transferase (GGT) were significantly higher in patients with the MetS than in subjects without the MetS (34+/-21 vs. 29+/-20 U/l; p<0.001, 1.16+/-0.39 vs. 1.00+/-0.36 U/l, p<0.001; and 53+/-88 vs. 43+/-57 U/l, p=0.001, respectively) but were similar in patients with significant CAD as in those who did not have significant CAD at angiography (p=0.592; p=0.731, and p=0.716, respectively). Analysis of covariance after multivariate adjustment including alcohol consumption confirmed that ALT, ALT/AST ratio, and GGT were significantly and independently associated with the MetS but not with significant CAD.

CONCLUSIONS

ALT, the ALT/AST ratio, and GGT are associated with the MetS but not with angiographically determined coronary atherosclerosis.