Oral glucose tolerance test in Italian overweight/obese children and adolescents results in a very high prevalence of impaired fasting glycaemia, but not of diabetes.
BACKGROUND
Very few studies on glucose abnormalities in European overweight/obese children and adolescents are available, and scientific evidence on the value of standard oral glucose tolerance test (OGTT) in childhood is lacking. We therefore aimed to establish prevalence and features of impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and type 2 diabetes (T2D) in a large cohort of Italian overweight/obese children and adolescents and to assess the validity of standard OGTT in the paediatric population.


METHODS
This is a 1-year observational study conducted on 736 (535 overweight/obese and 201 normal weight) consecutive paediatric patients attending the outpatient clinic of Paediatric Endocrine Unit. Clinical and biochemical parameters were collected for all participants. All overweight/obese subjects underwent OGTT.


RESULTS
We observed a high prevalence of IFG (7.66%), more than twice that observed in other European children, but a low prevalence of IGT (3.18%) and T2D (0.18%). IFG was useless to predict IGT, having very low predictive value (7.3%) and sensitivity (17.6%). Compared to normal weight children, overweight/obese subjects showed significant differences in most metabolic and clinical parameters. In the overweight/obese group, having hyperglycaemia was associated to significantly higher blood pressure, homeostasis model assessment for insulin resistance, insulin and triglycerides.


CONCLUSIONS
In our children, the prevalence of IFG is higher than that reported in other European cohorts, whereas T2D is rare. IFG appears not useful to detect IGT in childhood. Paediatric diagnostic cut-points, glucose load and timing of sampling need to be further validated to define glucose abnormalities in obese children that, compared with normal weight subjects, already are characterised by a different metabolic phenotype.
Cambuli
Valentina M
VM
Endocrinology and Metabolism, Department of Medical Sciences, University of Cagliari, Cagliari, Italy.
Incani
Michela
M
Pilia
Sabrina
S
Congiu
Tiziana
T
Cavallo
M Gisella
MG
Cossu
Efisio
E
Sentinelli
Federica
F
Mariotti
Stefano
S
Loche
Sandro
S
Baroni
Marco G
MG
D000293:Adolescent; D000375:Aging; D001786:Blood Glucose / Q000032:analysis*; D015992:Body Mass Index; D002648:Child; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis / Q000276:immunology; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000378:metabolism; D005260:Female; D018149:Glucose Intolerance / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000378:metabolism; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance; D007558:Italy / Q000453:epidemiology; D008055:Lipids / Q000097:blood; D008297:Male; D009765:Obesity / Q000150:complications* / Q000378:metabolism; D050177:Overweight / Q000150:complications* / Q000378:metabolism; D015995:Prevalence; D014527:Uric Acid / Q000097:blood
D001786:Blood Glucose; D008055:Lipids; D014527:Uric Acid