Effects of supervised exercise on gamma-glutamyl transferase levels in patients with isolated impaired fasting glucose and those with impaired fasting glucose plus impaired glucose tolerance.
OBJECTIVE
To study the effects of a supervised exercise program on serum gamma-glutamyl transferase (GGT), glycemic control and cardiovascular risk factors in pre-diabetic patients with isolated impaired fasting glucose (IFG) and those with IFG plus impaired glucose tolerance (IGT).


METHODS
Out of 60 pre-diabetic patients (30 with isolated IFG and 30 with IFG + IGT) 24 were randomly assigned to the supervised exercise program (1 h twice a week) and 36 only obtained counselling on the risk of diabetes and its prevention. Patients have been followed over a 12-month period.


RESULTS
The main findings were that patients with IFG + IGT had increased GGT levels at baseline (49.2±27.4 U/L) compared to subjects with isolated IFG (28.1±21.9 U/L) (p<0.01), and that GGT levels improved only after the supervised exercise intervention within the IFG + IGT subjects ( - 17.7±19.6 U/L). Similarly, baseline triglyceride levels were also higher in IFG + IGT patients (p<0.001) and there was a decrease through exercise intervention in these patients only (p<0.05).


CONCLUSIONS
GGT is an unspecific marker of oxidative stress and both high plasma glucose and triglycerides levels may produce oxidative stress. Thus, patients with IFG + IGT seem to have higher levels of oxidative stress than those with isolated IFG. Based on the known association between GGT levels and cardiovascular risk factors, IFG + IGT patients may be at higher risk for the development of cardiovascular diseases. The specific effect of regular exercise on GGT in pre-diabetic patients may contribute to the understanding of the preventive effects related to exercise.
Department of Sport Science, Medical Section, University of Innsbruck, Austria. martin.burtscher@uibk.ac.at
M
M
Burtscher
H
H
Gatterer
T
T
Dünnwald
D
D
Pesta
M
M
Faulhaber
N
N
Netzer
R
R
Koch
K
K
König
H
H
Ulmer
D000328:Adult; D000368:Aged; D001317:Austria / Q000453:epidemiology; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000453:epidemiology; D015444:Exercise; D005260:Female; D018149:Glucose Intolerance / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D006943:Hyperglycemia / Q000209:etiology / Q000517:prevention & control*; D015228:Hypertriglyceridemia / Q000209:etiology / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000150:complications; D018384:Oxidative Stress; D011236:Prediabetic State / Q000097:blood / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D055070:Resistance Training; D012307:Risk Factors; D005723:gamma-Glutamyltransferase / Q000097:blood*
D015415:Biomarkers; D005723:gamma-Glutamyltransferase; C554782:gamma-glutamyltransferase, human