Gamma-glutamyl transferase is strongly associated with degree of overweight and sex

Uric acid and gamma-glutamyl-transferase in children and adolescents with obesity: Association to anthropometric measures and cardiometabolic risk markers depending on pubertal stage, sex, degree of weight loss and type of patient care: Evaluation of the adiposity patient follow-up registry

OBJECTIVES

Associations between body mass index (BMI)- standard deviation score (SDS)/waist-to-height ratio (WHtR) were studied with (i) serum uric acid (sUA)/gamma-glutamyl-transferase (GGT) and (ii) cardiometabolic risk markers in children with obesity, considering sex, pubertal development, and degree of weight loss/type of patient care.

METHODS

102 936 children from the Adiposity-Follow-up registry (APV; 47% boys) were included. Associations were analysed between sUA/GGT and anthropometrics, transaminases, lipids, fasting insulin (FI), homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides to HDL-cholesterol (TG/HDL)-ratio. Follow-up analyses (3-24 months after baseline) considered a BMI-SDS reduction ≥0.2 (n = 11 096) or ≥0.5 (n = 3728). Partialized correlation analyses for sex and BMI-SDS were performed, taking pubertal development into consideration.

RESULTS

At baseline, BMI-SDS showed the strongest correlations to sUA (r = 0.35; n = 26 529), HOMA-IR/FI (r = 0.30; n = 5513 /n = 5880), TG/HDL-ratio (r = 0.23; n = 24 501), and WHtR to sUA (r = 0.32; n = 10 805), GGT (r = 0.34; n = 11 862) and Alanine-aminotransferase (ALAT) (r = 0.33; n = 11 821), with stronger correlations in boys (WHtR and GGT: r = 0.36, n = 5793) and prepubertal children (r = 0.36; n = 2216). GGT and sUA (after partializing effects of age, sex, BMI-SDS) showed a correlation to TG/HDL-ratio (r = 0.27; n = 24 501). Following a BMI-SDS reduction ≥0.2 or ≥0.5, GGT was most strongly related to Aspartate-aminotransferase (ASAT)/ ALAT, most evident in prepuberty and with increasing weight loss, and also to TG/HDL-ratio (r = 0.22; n = 1528). Prepubertal children showed strongest correlations between BMI-SDS/WHtR and GGT. ΔBMI-SDS was strongly correlated to ΔsUA (r = 0.30; n = 4160) and ΔGGT (r = 0.28; n = 3562), and ΔWHtR to ΔGGT (r = 0.28; n = 3562) (all p < 0.0001).

CONCLUSION

Abdominal obesity may trigger hyperuricemia and hepatic involvement already in prepuberty. This may be stronger in infancy than anticipated to date. Even moderate weight loss has favourable effects on cardiometabolic risk profile and glucose homeostasis.

Increased liver echogenicity and liver enzymes are associated with extreme obesity, adolescent age and male gender: analysis from the German/Austrian/Swiss obesity registry APV

Background

Childhood obesity is often associated with non-alcoholic fatty liver disease (NAFLD), the most common chronic liver disease in pediatrics.

Methods

This multi-center study analyzed liver echogenicity and liver enzymes in relation to obesity, age, gender and comorbidities. Data were collected using a standardized documentation software (APV) from 1.033 pediatric patients (age: 4–18 years, body mass index = BMI: 28–36 kg/m², 50% boys) with overweight (BMI >90th percentile), obesity (BMI >97th percentile) or extreme obesity (BMI > 99.5th percentile) and obesity related comorbidities, especially NAFLD from 26 centers of Germany, Austria and Switzerland. Liver enzymes aspartate aminotransferase (AST), alanine-aminotransferase (ALT) and gamma glutamyltransferase (gammaGT) were evaluated using 2 cut-off values a) > 25 U/L and b) > 50 U/L. Multiple logistic regression models were used for statistical analysis.

Results

In total, 44% of the patients showed increased liver echogenicity. Liver enzymes > 25 U/L were present in 64% and > 50 U/L in 17%. Increased liver echogenicity was associated with elevated liver enzymes (> 25 U/L: odds ratio (OR) = 1.4, 95% CI: 1.1–1.9, P < 0.02; > 50 U/L: OR = 3.5, 95% CI: 2.4–5.1, P < 0.0001). Extreme obesity, adolescence and male gender were associated with increased liver echogenicity (extreme obesity vs overweight OR = 3.5, 95% CI: 1.9–6.1, P < 0.0001; age > 14 years vs age < 9 years OR = 2.2, 95% CI: 1.4–3.5, P < 0.001; boys vs girls OR = 1.6, 95% CI: 1.2–2.0, P < 0.001) and elevated liver enzymes (extreme obesity vs overweight > 25 U/L: OR = 4.1, 95% CI: 2.4–6.9, P < 0.0001; > 50 U/L: OR = 18.5, 95% CI: 2.5–135, P < 0.0001; age > 14 years vs age < 9 years > 50 U/L: OR = 1.9, 95% CI: 1.0–3.7, P > 0.05; boys vs girls > 25 U/L: OR = 3.1, 95% CI: 2.4–4.1, P < 0.0001; > 50 U/L: OR = 2.1, 95% CI: 1.5–2.9, P < 0.0001). Impaired glucose metabolism showed a significant correlation with elevated liver enzymes > 50 U/L (OR = 4.4, 95% CI: 1.6–11.8, P < 0.005). Arterial hypertension seemed to occur in patients with elevated liver enzymes > 25 U/L (OR 1.6, 95% CI: 1.2–2.0, P < 0.005).

Conclusions

NAFLD is strongly related to extreme obesity in male adolescents. Moreover impaired glucose tolerance was observed in patients with elevated liver enzymes > 50 U/L, but arterial hypertension was only present in patients with moderately elevated liver enzymes > 25 U/L.

Predictive Value of Serum Gamma-glutamyltranspeptidase for Future Cardiometabolic Dysregulation in Adolescents- a 10-year longitudinal study

Serum gamma-glutamyltransferase (γ-GT) is implicated in the pathogenesis of atherosclerosis and metabolic syndrome (MetS) in adults. The relationships between γ-GT and cardiometabolic dysregulation remains unclear in adolescents. We enrolled 7,072 Taiwanese adolescents and followed them for a median of 6.8 years. The optimal cut-off values (CoVs) of baseline γ-GT to predict future MetS, hypertension (HTN), and type 2 diabetes (T2DM) were determined by receiving operating characteristic (ROC) curve. Using these CoVs, the participants were divided into normal- and high-level groups. Cox proportional hazard analysis was used to calculate hazard ratios (HRs) for the subjects with a high level of γ-GT for the risk of future cardiometabolic dysregulation. Serum γ-GT was significantly higher in the subjects with MetS than in those without MetS at baseline (p < 0.001). The optimal CoVs of γ-GT were 12 U/L for boys and 11 U/L for girls. In multivariate Cox regression analysis, a higher serum γ-GT level increased the risk of future MetS (HRs 1.98 and 2.85 for boys and girls, respectively, both p < 0.001), but not new onset HTN and T2DM. In conclusion, serum γ-GT levels not only demonstrated an excellent correlation with the presence of MetS and also in predicting future MetS in adolescents.

The one year exercise and lifestyle intervention program KLAKS: Effects on anthropometric parameters, cardiometabolic risk factors and glycemic control in childhood obesity

OBJECTIVE

Regular physical exercise within structured lifestyle programs may improve weight status and minimize metabolic risk factors in childhood obesity. The aim of this study was to evaluate the effect of the one-year combined physical exercise/lifestyle program KLAKS on anthropometric and metabolic parameters and glycemic control in childhood obesity.

MATERIALS AND METHODS

142 overweight/obese (BMI>90th percentile) candidates (7-18years) were enrolled, 115 participants completed the program. Anthropometrics and biochemical parameters were obtained at beginning and completion. An oral glucose tolerance test (OGTT) was performed in a subgroup of participants. Course of glucose and insulin levels within OGTT was correlated with several parameters and is reported here for those who completed the program.

RESULTS

The mean standard deviation scores (SDS) decreased significantly for BMI, waist circumference, waist-to-height ratio (WHtR) and percentage body fat (all p≤0.01). Improved metabolic risk markers included mean glucose levels within an OGTT at follow-up compared to baseline (p<0.0001) and HbA1c (p=0.05) as well as indications of improvement for gamma-glutamyl-transferase and free fatty acids.

CONCLUSIONS

The one-year combined exercise/lifestyle program KLAKS significantly improves markers of obesity and glycemic control. Impaired cardiometabolic risk markers, even subclinical, are also favorably influenced by program participation.

A case report and review of the literature of laparoscopic sleeve gastrectomy in morbidly obese adolescents: beyond metabolic surgery and visceral fat reduction

OBJECTIVE

Data on safety, effectiveness and amelioration of metabolic comorbidities are scarce for adolescents undergoing laparoscopic sleeve gastrectomy (LSG).

METHODS

Data on a 17 year-old female who underwent LSG due to morbid obesity and quantification of visceral adipose tissue (VAT)/hepatic fat (HF) by MRI scan are presented. In addition, a review of the literature related to LSG in adolescent obesity is provided [search terms: laparoscopic sleeve gastrectomy, adolescence, obesity].

RESULTS

Pre-existing comorbidities in our patient included insulin resistance, NASH (HF: 28%) and hyperuricemia. BMI dropped from 52.9 kg/m(2) to 40.4 and 35.0 kg/m(2) after 6 and 24 months, respectively, following LSG. VAT dropped by 49.2% and by 71.5% within 6 and 24 months, accompanied by a decrease of HF to 1.53% and to 0.85%, respectively. Improvements of metabolic parameters towards normal range, which were reached within 6 months following LSG, could be maintained for 2 years. The review of the literature revealed that 9 original papers on LSG in adolescent obesity are available to date, ranging from single case presentations to case series of 108 patients and including children and adolescents 8-18 years.

CONCLUSIONS

LSG is a safe and - in the short term - effective bariatric procedure for adolescent obesity (follow up 24 months). Long-term results with larger numbers of patients and involving additional features, such as quantification of VAT and HF as markers of metabolic risk and insulin resistance, are warranted to further understand the effectiveness and safety and to further explore the long-term benefits of this procedure in adolescence.

The clinical importance of serum γ-glutamyltransferase level as an early predictor of obesity development in Korean men

BACKGROUND AND OBJECTIVE

Serum γ-glutamyl transferase (GGT) levels are known to be positively associated with obesity. We aimed at verifying an association between baseline GGT levels and the development of obesity in Korean men.

PATIENTS AND METHODS

This prospective cohort study was performed on 18,510 initially non-obese Korean men. The total follow-up period was 66,993.3 person years and the average follow-up period was 3.62 years (standard deviation [SD], 1.44). Cox proportional hazards model was used to determine hazard ratios for the risk of obesity development.

RESULTS

We found a strong positive association between serum GGT levels at baseline and obesity development, after adjusting for multiple covariates. The risk of obesity development was found to be significantly and dose-dependently associated with serum GGT level. Moreover, estimated hazard ratios for severe obesity (BMI (body mass index) ≥30 kg/m(2)) attributable to serum GGT levels were much higher than those for obesity (BMI ≥ 25 kg/m(2)). The significant association was also found for WC (waist circumference)-defined obesity (WC > 90 cm).

CONCLUSIONS

Our findings, which were obtained from a large cohort, indicate that serum GGT is an early predictor of obesity development. Furthermore, this association was remained significant after adjusting for multiple baseline covariates.