Lack of agreement between the revised criteria of impaired fasting glucose and impaired glucose tolerance in children with excess body weight.
OBJECTIVE
The aim of this study was to describe the agreement between impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) in children with excess body weight using the original and the revised definitions of IFG.


METHODS
Obese and overweight children aged 4-17 years were included (n = 533). Anthropometric parameters and biochemical tests (fasting and 2-h glucose tests after an oral glucose load [1.75 g/kg]) were performed. Case subjects with a fasting plasma glucose >/=126 mg/dl were excluded. The diagnostic parameters of the original and the revised definitions of IFG for detecting IGT were estimated. The analysis of agreement between these categories was made using the kappa test.


RESULTS
The prevalence of IFG increased from 6.2 to 13.3% using the new criteria. The prevalence of IFG became closer to the prevalence of IGT (14.8%). The revised criteria increased the sensitivity from 26.6 to 36.7%. However, the new IFG definition was not useful for identifying IGT cases. Of the 71 case subjects with IFG, only 29 (40.8%) had IGT. In addition, 50 case subjects with IGT (9.4%) and 13 with diabetes (2.4%) had a fasting glycemia <100 mg/dl. A poor agreement was found between the 2003 IFG definition and abnormal 2-h postchallenge plasma glucose (kappa = 0.359). The proportion of false-positive cases increased (36.3-59.1%) under the new definition.


CONCLUSIONS
The new definition modestly increases the sensitivity of IFG for detecting IGT in children with excess body weight. Despite this, more than one-half of these cases are not detected. In addition, the false-positive rate was increased by 61%.
Gómez-Díaz
Rita
R
Servicio de Endocrinología Pediátrica, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México City, D.F., México. ritagomezdiaz@netscape.net
Aguilar-Salinas
Carlos A
CA
Morán-Villota
Segundo
S
Barradas-González
Rosalinda
R
Herrera-Márquez
Rocio
R
Cruz López
Miguel
M
Kumate
Jesus
J
Wacher
Niels H
NH
D000293:Adolescent; D001786:Blood Glucose / Q000378:metabolism*; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D005215:Fasting; D005260:Female; D018149:Glucose Intolerance / Q000145:classification / Q000453:epidemiology*; D005951:Glucose Tolerance Test; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D009765:Obesity / Q000145:classification / Q000453:epidemiology*; D018579:Patient Selection; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity
D001786:Blood Glucose