The Association of Metabolic Syndrome and Serum γ-Glutamyl Transpeptidase: A 4-Year Cohort Study of 3,698 Korean Male Workers

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.

The role of diet and intestinal microbiota in the development of metabolic syndrome

Metabolic syndrome (MetS) is a cluster of metabolic factors that increase the risk of cardiovascular disease and type 2 diabetes mellitus (T2DM), which is in itself a major cardiovascular disease risk factor. The aim of this review is to summarize the data related to the influence of the gut microbiota on the development of obesity and the MetS, highlighting the role of diet in controlling the MetS by modifying the gut microbiota. The main alterations in the gut microbiota of individuals with MetS consist of an increased Firmicutes/Bacteriodetes ratio and a reduced capacity to degrade carbohydrates to short-chain fatty acids, which in turn is related with the metabolic dysfunction of the host organism rather than with obesity itself. In addition to a low-fat, high-carbohydrate diet, with its high fiber intake, a diet with 30% fat content but with a high content in fruit and vegetables, such as the Mediterranean diet, is beneficial and partially restores the dysbiosis found in individuals with MetS. Overall, the shaping of the gut microbiota through the administration of prebiotics or probiotics increases the short-chain fatty acid production and is therefore a valid alternative in MetS treatment.

Shift Work Is Associated with Metabolic Syndrome in Young Female Korean Workers

Background

Shift work is associated with health problems, including metabolic syndrome. This study investigated the association between shift work and metabolic syndrome in young workers.

Methods

A total of 3,317 subjects aged 20–40 years enrolled in the 2011–2012 Korean National Health and Nutrition Examination Survey were divided into shift and day workers. We conducted a cross-sectional study and calculated odds ratios using multivariate logistic regression analysis in order to examine the association between shift work and metabolic syndrome.

Results

The prevalence of metabolic syndrome was 14.3% and 7.1% among male and female shift workers, respectively. After adjusting for confounding factors, shift work was associated with metabolic syndrome in female workers (odds ratio, 2.53; 95% confidence interval, 1.12 to 5.70).

Conclusion

Shift work was associated with metabolic syndrome in young women. Timely efforts are necessary to manage metabolic syndrome in the workplace.

The NAFL Risk Score: A simple scoring model to predict 4-y risk for non-alcoholic fatty liver

BACKGROUND

Although several risk factors for non-alcoholic fatty liver (NAFL) have been reported, there are few clinical scores that predict its incidence in the long term. We developed and validate a scoring model for individual prediction of 4-y risk for NAFL.

METHODS

Four-year follow-up data of 8226 initially NAFL-free subjects enrolled for an annual physical examination from Wenzhou Medical Center were analyzed. These subjects are randomly split into the training and the validation cohort. Univariate and multivariable logistic regression models were employed for model development. The selected variables were assigned an integer or half-integer risk score proportional to the estimated coefficient from the logistic model. Risk scores were tested in a validation cohort. We also compared the predictive performance of with that of the NAFLD Index by computing the area under the receiver operating characteristic curve (AUROC).

RESULTS

The NAFL Risk Score was developed as 0 to 18 points comprising of BMI, TG×GGT, ALT/AST, LDL-C/HDL-C and UA in both sexes. Comparison of the observed with the estimated incidence of NAFL at both cohorts showed satisfactory precision. In addition, the NAFL Risk Score showed relatively good discriminative power (AUROC=0.739 for males, 0.823 for females) compared with the NAFLD Index (AUROC=0.661 for males, 0.729 for females) in these Chinese subjects.

CONCLUSIONS

We developed and validated the NAFL Risk Score, a new scoring model to predict 4-y risk for NAFL. The NAFL Risk Score may be clinically simple and useful for assessing individual risk for NAFL.

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.

A possible role of serum uric acid as a marker of metabolic syndrome

BACKGROUND/AIMS

The association between serum uric acid (SUA) levels and metabolic syndrome (MetS) has recently been reported in several cross-sectional and longitudinal studies. We investigated SUA as a biomarker to predict future development of MetS in healthy Korean men without diabetes or hypertension and determined the optimal cut-off levels of SUA.

METHODS

A retrospective cohort study was conducted using data from healthy men who received a general health check-up in 2003. A total of 1809 participants free of MetS, diabetes and hypertension was enrolled. Participants were classified into three groups based on SUA levels: group 1 (<5.5 mg/dL), group 2 (5.5-6.9 mg/dL) and group 3 (≥7.0 mg/dL).

RESULTS

During 13,802 person-years of follow up, 127 participants developed MetS. After adjusting for multiple associated parameters, SUA was significantly associated with incident MetS (hazard ratios comparing groups 2 and 3 vs group 1, 2.45 and 3.47 respectively; P < 0.001). In receiver operating characteristic curve analysis, the optimal cut-off level for SUA to predict the development of MetS was 6.5 mg/dL.

CONCLUSION

Our results indicate that an increased level of SUA, even within the normal range, is associated with future development of MetS in healthy middle-aged men.

Oral administration of Bifidobacterium breve B-3 modifies metabolic functions in adults with obese tendencies in a randomised controlled trial

Accumulating evidence suggests an association between gut microbiota and the development of obesity, raising the possibility of probiotic administration as a therapeutic approach. Bifidobacterium breve B-3 was found to exhibit an anti-obesity effect on high-fat diet-induced obesity mice. In the present study, a randomised, double-blind, placebo-controlled trial was conducted to evaluate the effect of the consumption of B. breve B-3 on body compositions and blood parameters in adults with a tendency for obesity. After a 4-week run-in period, the participants were randomised to receive either placebo or a B-3 capsule (approximately 5 × 10¹⁰ colony-forming units of B-3/d) daily for 12 weeks. A significantly lowered fat mass was observed in the B-3 group compared with the placebo group at week 12. Improvements were observed for some blood parameters related to liver functions and inflammation, such as γ-glutamyltranspeptidase and high-sensitivity C-reactive protein. Significant correlations were found between the changed values of some blood parameters and the changed fat mass in the B-3 group. These results suggest the beneficial potential of B. breve B-3 in improving metabolic disorders.

γ-glutamyl transpeptidase in men and alanine aminotransferase in women are the most suitable parameters among liver function tests for the prediction of metabolic syndrome in nonviral hepatitis and nonfatty liver in the elderly

BACKGROUND/AIMS

Nonalchoholic fatty liver disease (NAFLD) has been reported as a hepatic manifestation of metabolic syndrome (MetS); it is common and accounts for 80% of the cases with abnormal liver function tests (LFTs). In addition, several studies have proved that there is a correlation between abnormal LFTs and MetS. Therefore, LFTs may represent the abnormal metabolic status of livers in the patients with MetS. To identify the early state of metabolic dysfunction, we investigate the value of LFTs for the future MetS development in the relatively healthy (non-NAFLD) elderly.

PATIENTS AND METHODS

A total of 16,912 subjects met the criteria for analysis. In the first stage of this study, subjects were enrolled in the cross-sectional study in order to find out the optimal cutoff value in different LFTs with higher chances to have MetS. In the second stage of the present study, subjects with MetS at baseline were excluded from the same study group, and a median 5.6-year longitudinal study was conducted on the rest of the group.

RESULTS

Among all LFTs, only aspartate aminotransferase in both genders and the α-fetal protein in women failed to show the significance in distinguishing subjects with MetS by the receiver operating characteristic curve. In the Kaplan-Meier plot, only γ-glutamyl transpeptidase (γ-GT) in men and the alanine aminotransferase (ALT) in women could be used to successfully separate subjects with higher risk of developing the MetS from those with lower risk. Finally, in the multivariant Cox regression model, similar results were identified. Still, the hazard ratio (HR) to have future MetS, γ-GT in men, and ALT in women showed significance (HR = 1.511 in men and 1.504 in women).

CONCLUSION

Among all the different LFTs, γ-GT (>16 U/L) in male and ALT (>21 U/L) in female were the best predictors for the development of MetS in healthy elderly. These two liver markers could be an ancillary test in predicting future MetS development/diagnosis. Elevation of the LFTs without underlying liver diseases should be treated as a warning sign of the possible MetS development in the elderly.

Association between γ-glutamyl transferase and metabolic syndrome: a cross-sectional study of an adult population in Beijing

The relationship between liver enzymes and clustered components of metabolic syndrome (MetS) is explored and the predictive power of γ-glutamyl transferase (GGT) for the diagnosis of MetS in an adult population in Beijing is investigated. A total of 10,553 adults aged 20-65 years who underwent health examinations at Beijing Tongren Hospital in 2012 were enrolled in the study. Multivariate logistic regression analysis is conducted to determine the associations between the levels of various liver enzymes and clustered components of MetS. A receiver operating characteristic analysis is used to determine the optimal cut-off value of GGT for the diagnosis of MetS. A high level of GGT is found to be positively associated with clustered components of MetS in both men and women after adjusting for age, body mass index (BMI), history of alcoholic fatty liver, and the presence of taking anti-hypertensive, anti-dyslipidemic, and anti-diabetic drugs. Among all components of MetS, GGT is more predictive of triglyceride, and BMI. The area-under-the-curve values of GGT for discriminating MetS from normal metabolic status in men and women are 0.73 and 0.80, respectively. The optimal cut-off value of GGT for men is 31.50 U/L, demonstrating a sensitivity of 74.00% and specificity of 62.00%. For women, it is 19.50 U/L (sensitivity 76.00% and specificity 70.00%). GGT is therefore recommended as a useful diagnostic marker for MetS, because the test is inexpensive, highly sensitive, and frequently encountered in clinical practice.